Fragment.java revision 15c21ffad983afdcd69c55ed1a2b40d2c281892d
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.app; 18 19import android.animation.Animator; 20import android.annotation.CallSuper; 21import android.annotation.NonNull; 22import android.annotation.Nullable; 23import android.annotation.StringRes; 24import android.content.ComponentCallbacks2; 25import android.content.Context; 26import android.content.Intent; 27import android.content.IntentSender; 28import android.content.res.Configuration; 29import android.content.res.Resources; 30import android.content.res.TypedArray; 31import android.os.Build; 32import android.os.Build.VERSION_CODES; 33import android.os.Bundle; 34import android.os.Looper; 35import android.os.Parcel; 36import android.os.Parcelable; 37import android.os.UserHandle; 38import android.transition.Transition; 39import android.transition.TransitionInflater; 40import android.transition.TransitionSet; 41import android.util.AndroidRuntimeException; 42import android.util.ArrayMap; 43import android.util.AttributeSet; 44import android.util.DebugUtils; 45import android.util.SparseArray; 46import android.util.SuperNotCalledException; 47import android.view.ContextMenu; 48import android.view.ContextMenu.ContextMenuInfo; 49import android.view.LayoutInflater; 50import android.view.Menu; 51import android.view.MenuInflater; 52import android.view.MenuItem; 53import android.view.View; 54import android.view.View.OnCreateContextMenuListener; 55import android.view.ViewGroup; 56import android.widget.AdapterView; 57 58import java.io.FileDescriptor; 59import java.io.PrintWriter; 60import java.lang.reflect.InvocationTargetException; 61 62/** 63 * A Fragment is a piece of an application's user interface or behavior 64 * that can be placed in an {@link Activity}. Interaction with fragments 65 * is done through {@link FragmentManager}, which can be obtained via 66 * {@link Activity#getFragmentManager() Activity.getFragmentManager()} and 67 * {@link Fragment#getFragmentManager() Fragment.getFragmentManager()}. 68 * 69 * <p>The Fragment class can be used many ways to achieve a wide variety of 70 * results. In its core, it represents a particular operation or interface 71 * that is running within a larger {@link Activity}. A Fragment is closely 72 * tied to the Activity it is in, and can not be used apart from one. Though 73 * Fragment defines its own lifecycle, that lifecycle is dependent on its 74 * activity: if the activity is stopped, no fragments inside of it can be 75 * started; when the activity is destroyed, all fragments will be destroyed. 76 * 77 * <p>All subclasses of Fragment must include a public no-argument constructor. 78 * The framework will often re-instantiate a fragment class when needed, 79 * in particular during state restore, and needs to be able to find this 80 * constructor to instantiate it. If the no-argument constructor is not 81 * available, a runtime exception will occur in some cases during state 82 * restore. 83 * 84 * <p>Topics covered here: 85 * <ol> 86 * <li><a href="#OlderPlatforms">Older Platforms</a> 87 * <li><a href="#Lifecycle">Lifecycle</a> 88 * <li><a href="#Layout">Layout</a> 89 * <li><a href="#BackStack">Back Stack</a> 90 * </ol> 91 * 92 * <div class="special reference"> 93 * <h3>Developer Guides</h3> 94 * <p>For more information about using fragments, read the 95 * <a href="{@docRoot}guide/components/fragments.html">Fragments</a> developer guide.</p> 96 * </div> 97 * 98 * <a name="OlderPlatforms"></a> 99 * <h3>Older Platforms</h3> 100 * 101 * While the Fragment API was introduced in 102 * {@link android.os.Build.VERSION_CODES#HONEYCOMB}, a version of the API 103 * at is also available for use on older platforms through 104 * {@link android.support.v4.app.FragmentActivity}. See the blog post 105 * <a href="http://android-developers.blogspot.com/2011/03/fragments-for-all.html"> 106 * Fragments For All</a> for more details. 107 * 108 * <a name="Lifecycle"></a> 109 * <h3>Lifecycle</h3> 110 * 111 * <p>Though a Fragment's lifecycle is tied to its owning activity, it has 112 * its own wrinkle on the standard activity lifecycle. It includes basic 113 * activity lifecycle methods such as {@link #onResume}, but also important 114 * are methods related to interactions with the activity and UI generation. 115 * 116 * <p>The core series of lifecycle methods that are called to bring a fragment 117 * up to resumed state (interacting with the user) are: 118 * 119 * <ol> 120 * <li> {@link #onAttach} called once the fragment is associated with its activity. 121 * <li> {@link #onCreate} called to do initial creation of the fragment. 122 * <li> {@link #onCreateView} creates and returns the view hierarchy associated 123 * with the fragment. 124 * <li> {@link #onActivityCreated} tells the fragment that its activity has 125 * completed its own {@link Activity#onCreate Activity.onCreate()}. 126 * <li> {@link #onViewStateRestored} tells the fragment that all of the saved 127 * state of its view hierarchy has been restored. 128 * <li> {@link #onStart} makes the fragment visible to the user (based on its 129 * containing activity being started). 130 * <li> {@link #onResume} makes the fragment begin interacting with the user 131 * (based on its containing activity being resumed). 132 * </ol> 133 * 134 * <p>As a fragment is no longer being used, it goes through a reverse 135 * series of callbacks: 136 * 137 * <ol> 138 * <li> {@link #onPause} fragment is no longer interacting with the user either 139 * because its activity is being paused or a fragment operation is modifying it 140 * in the activity. 141 * <li> {@link #onStop} fragment is no longer visible to the user either 142 * because its activity is being stopped or a fragment operation is modifying it 143 * in the activity. 144 * <li> {@link #onDestroyView} allows the fragment to clean up resources 145 * associated with its View. 146 * <li> {@link #onDestroy} called to do final cleanup of the fragment's state. 147 * <li> {@link #onDetach} called immediately prior to the fragment no longer 148 * being associated with its activity. 149 * </ol> 150 * 151 * <a name="Layout"></a> 152 * <h3>Layout</h3> 153 * 154 * <p>Fragments can be used as part of your application's layout, allowing 155 * you to better modularize your code and more easily adjust your user 156 * interface to the screen it is running on. As an example, we can look 157 * at a simple program consisting of a list of items, and display of the 158 * details of each item.</p> 159 * 160 * <p>An activity's layout XML can include <code><fragment></code> tags 161 * to embed fragment instances inside of the layout. For example, here is 162 * a simple layout that embeds one fragment:</p> 163 * 164 * {@sample development/samples/ApiDemos/res/layout/fragment_layout.xml layout} 165 * 166 * <p>The layout is installed in the activity in the normal way:</p> 167 * 168 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 169 * main} 170 * 171 * <p>The titles fragment, showing a list of titles, is fairly simple, relying 172 * on {@link ListFragment} for most of its work. Note the implementation of 173 * clicking an item: depending on the current activity's layout, it can either 174 * create and display a new fragment to show the details in-place (more about 175 * this later), or start a new activity to show the details.</p> 176 * 177 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 178 * titles} 179 * 180 * <p>The details fragment showing the contents of a selected item just 181 * displays a string of text based on an index of a string array built in to 182 * the app:</p> 183 * 184 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 185 * details} 186 * 187 * <p>In this case when the user clicks on a title, there is no details 188 * container in the current activity, so the titles fragment's click code will 189 * launch a new activity to display the details fragment:</p> 190 * 191 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 192 * details_activity} 193 * 194 * <p>However the screen may be large enough to show both the list of titles 195 * and details about the currently selected title. To use such a layout on 196 * a landscape screen, this alternative layout can be placed under layout-land:</p> 197 * 198 * {@sample development/samples/ApiDemos/res/layout-land/fragment_layout.xml layout} 199 * 200 * <p>Note how the prior code will adjust to this alternative UI flow: the titles 201 * fragment will now embed the details fragment inside of this activity, and the 202 * details activity will finish itself if it is running in a configuration 203 * where the details can be shown in-place. 204 * 205 * <p>When a configuration change causes the activity hosting these fragments 206 * to restart, its new instance may use a different layout that doesn't 207 * include the same fragments as the previous layout. In this case all of 208 * the previous fragments will still be instantiated and running in the new 209 * instance. However, any that are no longer associated with a <fragment> 210 * tag in the view hierarchy will not have their content view created 211 * and will return false from {@link #isInLayout}. (The code here also shows 212 * how you can determine if a fragment placed in a container is no longer 213 * running in a layout with that container and avoid creating its view hierarchy 214 * in that case.) 215 * 216 * <p>The attributes of the <fragment> tag are used to control the 217 * LayoutParams provided when attaching the fragment's view to the parent 218 * container. They can also be parsed by the fragment in {@link #onInflate} 219 * as parameters. 220 * 221 * <p>The fragment being instantiated must have some kind of unique identifier 222 * so that it can be re-associated with a previous instance if the parent 223 * activity needs to be destroyed and recreated. This can be provided these 224 * ways: 225 * 226 * <ul> 227 * <li>If nothing is explicitly supplied, the view ID of the container will 228 * be used. 229 * <li><code>android:tag</code> can be used in <fragment> to provide 230 * a specific tag name for the fragment. 231 * <li><code>android:id</code> can be used in <fragment> to provide 232 * a specific identifier for the fragment. 233 * </ul> 234 * 235 * <a name="BackStack"></a> 236 * <h3>Back Stack</h3> 237 * 238 * <p>The transaction in which fragments are modified can be placed on an 239 * internal back-stack of the owning activity. When the user presses back 240 * in the activity, any transactions on the back stack are popped off before 241 * the activity itself is finished. 242 * 243 * <p>For example, consider this simple fragment that is instantiated with 244 * an integer argument and displays that in a TextView in its UI:</p> 245 * 246 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 247 * fragment} 248 * 249 * <p>A function that creates a new instance of the fragment, replacing 250 * whatever current fragment instance is being shown and pushing that change 251 * on to the back stack could be written as: 252 * 253 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 254 * add_stack} 255 * 256 * <p>After each call to this function, a new entry is on the stack, and 257 * pressing back will pop it to return the user to whatever previous state 258 * the activity UI was in. 259 */ 260public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListener { 261 private static final ArrayMap<String, Class<?>> sClassMap = 262 new ArrayMap<String, Class<?>>(); 263 264 static final int INVALID_STATE = -1; // Invalid state used as a null value. 265 static final int INITIALIZING = 0; // Not yet created. 266 static final int CREATED = 1; // Created. 267 static final int ACTIVITY_CREATED = 2; // The activity has finished its creation. 268 static final int STOPPED = 3; // Fully created, not started. 269 static final int STARTED = 4; // Created and started, not resumed. 270 static final int RESUMED = 5; // Created started and resumed. 271 272 private static final Transition USE_DEFAULT_TRANSITION = new TransitionSet(); 273 274 int mState = INITIALIZING; 275 276 // When instantiated from saved state, this is the saved state. 277 Bundle mSavedFragmentState; 278 SparseArray<Parcelable> mSavedViewState; 279 280 // Index into active fragment array. 281 int mIndex = -1; 282 283 // Internal unique name for this fragment; 284 String mWho; 285 286 // Construction arguments; 287 Bundle mArguments; 288 289 // Target fragment. 290 Fragment mTarget; 291 292 // For use when retaining a fragment: this is the index of the last mTarget. 293 int mTargetIndex = -1; 294 295 // Target request code. 296 int mTargetRequestCode; 297 298 // True if the fragment is in the list of added fragments. 299 boolean mAdded; 300 301 // If set this fragment is being removed from its activity. 302 boolean mRemoving; 303 304 // Set to true if this fragment was instantiated from a layout file. 305 boolean mFromLayout; 306 307 // Set to true when the view has actually been inflated in its layout. 308 boolean mInLayout; 309 310 // True if this fragment has been restored from previously saved state. 311 boolean mRestored; 312 313 // True if performCreateView has been called and a matching call to performDestroyView 314 // has not yet happened. 315 boolean mPerformedCreateView; 316 317 // Number of active back stack entries this fragment is in. 318 int mBackStackNesting; 319 320 // The fragment manager we are associated with. Set as soon as the 321 // fragment is used in a transaction; cleared after it has been removed 322 // from all transactions. 323 FragmentManagerImpl mFragmentManager; 324 325 // Activity this fragment is attached to. 326 FragmentHostCallback mHost; 327 328 // Private fragment manager for child fragments inside of this one. 329 FragmentManagerImpl mChildFragmentManager; 330 331 // For use when restoring fragment state and descendant fragments are retained. 332 // This state is set by FragmentState.instantiate and cleared in onCreate. 333 FragmentManagerNonConfig mChildNonConfig; 334 335 // If this Fragment is contained in another Fragment, this is that container. 336 Fragment mParentFragment; 337 338 // The optional identifier for this fragment -- either the container ID if it 339 // was dynamically added to the view hierarchy, or the ID supplied in 340 // layout. 341 int mFragmentId; 342 343 // When a fragment is being dynamically added to the view hierarchy, this 344 // is the identifier of the parent container it is being added to. 345 int mContainerId; 346 347 // The optional named tag for this fragment -- usually used to find 348 // fragments that are not part of the layout. 349 String mTag; 350 351 // Set to true when the app has requested that this fragment be hidden 352 // from the user. 353 boolean mHidden; 354 355 // Set to true when the app has requested that this fragment be detached. 356 boolean mDetached; 357 358 // If set this fragment would like its instance retained across 359 // configuration changes. 360 boolean mRetainInstance; 361 362 // If set this fragment is being retained across the current config change. 363 boolean mRetaining; 364 365 // If set this fragment has menu items to contribute. 366 boolean mHasMenu; 367 368 // Set to true to allow the fragment's menu to be shown. 369 boolean mMenuVisible = true; 370 371 // Used to verify that subclasses call through to super class. 372 boolean mCalled; 373 374 // The parent container of the fragment after dynamically added to UI. 375 ViewGroup mContainer; 376 377 // The View generated for this fragment. 378 View mView; 379 380 // Whether this fragment should defer starting until after other fragments 381 // have been started and their loaders are finished. 382 boolean mDeferStart; 383 384 // Hint provided by the app that this fragment is currently visible to the user. 385 boolean mUserVisibleHint = true; 386 387 LoaderManagerImpl mLoaderManager; 388 boolean mLoadersStarted; 389 boolean mCheckedForLoaderManager; 390 391 // The animation and transition information for the fragment. This will be null 392 // unless the elements are explicitly accessed and should remain null for Fragments 393 // without Views. 394 AnimationInfo mAnimationInfo; 395 396 // True if the View was added, and its animation has yet to be run. This could 397 // also indicate that the fragment view hasn't been made visible, even if there is no 398 // animation for this fragment. 399 boolean mIsNewlyAdded; 400 401 // True if mHidden has been changed and the animation should be scheduled. 402 boolean mHiddenChanged; 403 404 // The cached value from onGetLayoutInflater(Bundle) that will be returned from 405 // getLayoutInflater() 406 LayoutInflater mLayoutInflater; 407 408 // Keep track of whether or not this Fragment has run performCreate(). Retained instance 409 // fragments can have mRetaining set to true without going through creation, so we must 410 // track it separately. 411 boolean mIsCreated; 412 413 /** 414 * State information that has been retrieved from a fragment instance 415 * through {@link FragmentManager#saveFragmentInstanceState(Fragment) 416 * FragmentManager.saveFragmentInstanceState}. 417 */ 418 public static class SavedState implements Parcelable { 419 final Bundle mState; 420 421 SavedState(Bundle state) { 422 mState = state; 423 } 424 425 SavedState(Parcel in, ClassLoader loader) { 426 mState = in.readBundle(); 427 if (loader != null && mState != null) { 428 mState.setClassLoader(loader); 429 } 430 } 431 432 @Override 433 public int describeContents() { 434 return 0; 435 } 436 437 @Override 438 public void writeToParcel(Parcel dest, int flags) { 439 dest.writeBundle(mState); 440 } 441 442 public static final Parcelable.ClassLoaderCreator<SavedState> CREATOR 443 = new Parcelable.ClassLoaderCreator<SavedState>() { 444 public SavedState createFromParcel(Parcel in) { 445 return new SavedState(in, null); 446 } 447 448 public SavedState createFromParcel(Parcel in, ClassLoader loader) { 449 return new SavedState(in, loader); 450 } 451 452 public SavedState[] newArray(int size) { 453 return new SavedState[size]; 454 } 455 }; 456 } 457 458 /** 459 * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when 460 * there is an instantiation failure. 461 */ 462 static public class InstantiationException extends AndroidRuntimeException { 463 public InstantiationException(String msg, Exception cause) { 464 super(msg, cause); 465 } 466 } 467 468 /** 469 * Default constructor. <strong>Every</strong> fragment must have an 470 * empty constructor, so it can be instantiated when restoring its 471 * activity's state. It is strongly recommended that subclasses do not 472 * have other constructors with parameters, since these constructors 473 * will not be called when the fragment is re-instantiated; instead, 474 * arguments can be supplied by the caller with {@link #setArguments} 475 * and later retrieved by the Fragment with {@link #getArguments}. 476 * 477 * <p>Applications should generally not implement a constructor. Prefer 478 * {@link #onAttach(Context)} instead. It is the first place application code can run where 479 * the fragment is ready to be used - the point where the fragment is actually associated with 480 * its context. Some applications may also want to implement {@link #onInflate} to retrieve 481 * attributes from a layout resource, although note this happens when the fragment is attached. 482 */ 483 public Fragment() { 484 } 485 486 /** 487 * Like {@link #instantiate(Context, String, Bundle)} but with a null 488 * argument Bundle. 489 */ 490 public static Fragment instantiate(Context context, String fname) { 491 return instantiate(context, fname, null); 492 } 493 494 /** 495 * Create a new instance of a Fragment with the given class name. This is 496 * the same as calling its empty constructor. 497 * 498 * @param context The calling context being used to instantiate the fragment. 499 * This is currently just used to get its ClassLoader. 500 * @param fname The class name of the fragment to instantiate. 501 * @param args Bundle of arguments to supply to the fragment, which it 502 * can retrieve with {@link #getArguments()}. May be null. 503 * @return Returns a new fragment instance. 504 * @throws InstantiationException If there is a failure in instantiating 505 * the given fragment class. This is a runtime exception; it is not 506 * normally expected to happen. 507 */ 508 public static Fragment instantiate(Context context, String fname, @Nullable Bundle args) { 509 try { 510 Class<?> clazz = sClassMap.get(fname); 511 if (clazz == null) { 512 // Class not found in the cache, see if it's real, and try to add it 513 clazz = context.getClassLoader().loadClass(fname); 514 if (!Fragment.class.isAssignableFrom(clazz)) { 515 throw new InstantiationException("Trying to instantiate a class " + fname 516 + " that is not a Fragment", new ClassCastException()); 517 } 518 sClassMap.put(fname, clazz); 519 } 520 Fragment f = (Fragment) clazz.getConstructor().newInstance(); 521 if (args != null) { 522 args.setClassLoader(f.getClass().getClassLoader()); 523 f.setArguments(args); 524 } 525 return f; 526 } catch (ClassNotFoundException e) { 527 throw new InstantiationException("Unable to instantiate fragment " + fname 528 + ": make sure class name exists, is public, and has an" 529 + " empty constructor that is public", e); 530 } catch (java.lang.InstantiationException e) { 531 throw new InstantiationException("Unable to instantiate fragment " + fname 532 + ": make sure class name exists, is public, and has an" 533 + " empty constructor that is public", e); 534 } catch (IllegalAccessException e) { 535 throw new InstantiationException("Unable to instantiate fragment " + fname 536 + ": make sure class name exists, is public, and has an" 537 + " empty constructor that is public", e); 538 } catch (NoSuchMethodException e) { 539 throw new InstantiationException("Unable to instantiate fragment " + fname 540 + ": could not find Fragment constructor", e); 541 } catch (InvocationTargetException e) { 542 throw new InstantiationException("Unable to instantiate fragment " + fname 543 + ": calling Fragment constructor caused an exception", e); 544 } 545 } 546 547 final void restoreViewState(Bundle savedInstanceState) { 548 if (mSavedViewState != null) { 549 mView.restoreHierarchyState(mSavedViewState); 550 mSavedViewState = null; 551 } 552 mCalled = false; 553 onViewStateRestored(savedInstanceState); 554 if (!mCalled) { 555 throw new SuperNotCalledException("Fragment " + this 556 + " did not call through to super.onViewStateRestored()"); 557 } 558 } 559 560 final void setIndex(int index, Fragment parent) { 561 mIndex = index; 562 if (parent != null) { 563 mWho = parent.mWho + ":" + mIndex; 564 } else { 565 mWho = "android:fragment:" + mIndex; 566 } 567 } 568 569 final boolean isInBackStack() { 570 return mBackStackNesting > 0; 571 } 572 573 /** 574 * Subclasses can not override equals(). 575 */ 576 @Override final public boolean equals(Object o) { 577 return super.equals(o); 578 } 579 580 /** 581 * Subclasses can not override hashCode(). 582 */ 583 @Override final public int hashCode() { 584 return super.hashCode(); 585 } 586 587 @Override 588 public String toString() { 589 StringBuilder sb = new StringBuilder(128); 590 DebugUtils.buildShortClassTag(this, sb); 591 if (mIndex >= 0) { 592 sb.append(" #"); 593 sb.append(mIndex); 594 } 595 if (mFragmentId != 0) { 596 sb.append(" id=0x"); 597 sb.append(Integer.toHexString(mFragmentId)); 598 } 599 if (mTag != null) { 600 sb.append(" "); 601 sb.append(mTag); 602 } 603 sb.append('}'); 604 return sb.toString(); 605 } 606 607 /** 608 * Return the identifier this fragment is known by. This is either 609 * the android:id value supplied in a layout or the container view ID 610 * supplied when adding the fragment. 611 */ 612 final public int getId() { 613 return mFragmentId; 614 } 615 616 /** 617 * Get the tag name of the fragment, if specified. 618 */ 619 final public String getTag() { 620 return mTag; 621 } 622 623 /** 624 * Supply the construction arguments for this fragment. 625 * The arguments supplied here will be retained across fragment destroy and 626 * creation. 627 * 628 * <p>This method cannot be called if the fragment is added to a FragmentManager and 629 * if {@link #isStateSaved()} would return true. Prior to {@link Build.VERSION_CODES#O}, 630 * this method may only be called if the fragment has not yet been added to a FragmentManager. 631 * </p> 632 */ 633 public void setArguments(Bundle args) { 634 // The isStateSaved requirement below was only added in Android O and is compatible 635 // because it loosens previous requirements rather than making them more strict. 636 // See method javadoc. 637 if (mIndex >= 0 && isStateSaved()) { 638 throw new IllegalStateException("Fragment already active"); 639 } 640 mArguments = args; 641 } 642 643 /** 644 * Return the arguments supplied to {@link #setArguments}, if any. 645 */ 646 final public Bundle getArguments() { 647 return mArguments; 648 } 649 650 /** 651 * Returns true if this fragment is added and its state has already been saved 652 * by its host. Any operations that would change saved state should not be performed 653 * if this method returns true, and some operations such as {@link #setArguments(Bundle)} 654 * will fail. 655 * 656 * @return true if this fragment's state has already been saved by its host 657 */ 658 public final boolean isStateSaved() { 659 if (mFragmentManager == null) { 660 return false; 661 } 662 return mFragmentManager.isStateSaved(); 663 } 664 665 /** 666 * Set the initial saved state that this Fragment should restore itself 667 * from when first being constructed, as returned by 668 * {@link FragmentManager#saveFragmentInstanceState(Fragment) 669 * FragmentManager.saveFragmentInstanceState}. 670 * 671 * @param state The state the fragment should be restored from. 672 */ 673 public void setInitialSavedState(SavedState state) { 674 if (mIndex >= 0) { 675 throw new IllegalStateException("Fragment already active"); 676 } 677 mSavedFragmentState = state != null && state.mState != null 678 ? state.mState : null; 679 } 680 681 /** 682 * Optional target for this fragment. This may be used, for example, 683 * if this fragment is being started by another, and when done wants to 684 * give a result back to the first. The target set here is retained 685 * across instances via {@link FragmentManager#putFragment 686 * FragmentManager.putFragment()}. 687 * 688 * @param fragment The fragment that is the target of this one. 689 * @param requestCode Optional request code, for convenience if you 690 * are going to call back with {@link #onActivityResult(int, int, Intent)}. 691 */ 692 public void setTargetFragment(Fragment fragment, int requestCode) { 693 // Don't allow a caller to set a target fragment in another FragmentManager, 694 // but there's a snag: people do set target fragments before fragments get added. 695 // We'll have the FragmentManager check that for validity when we move 696 // the fragments to a valid state. 697 final FragmentManager mine = getFragmentManager(); 698 final FragmentManager theirs = fragment != null ? fragment.getFragmentManager() : null; 699 if (mine != null && theirs != null && mine != theirs) { 700 throw new IllegalArgumentException("Fragment " + fragment 701 + " must share the same FragmentManager to be set as a target fragment"); 702 } 703 704 // Don't let someone create a cycle. 705 for (Fragment check = fragment; check != null; check = check.getTargetFragment()) { 706 if (check == this) { 707 throw new IllegalArgumentException("Setting " + fragment + " as the target of " 708 + this + " would create a target cycle"); 709 } 710 } 711 mTarget = fragment; 712 mTargetRequestCode = requestCode; 713 } 714 715 /** 716 * Return the target fragment set by {@link #setTargetFragment}. 717 */ 718 final public Fragment getTargetFragment() { 719 return mTarget; 720 } 721 722 /** 723 * Return the target request code set by {@link #setTargetFragment}. 724 */ 725 final public int getTargetRequestCode() { 726 return mTargetRequestCode; 727 } 728 729 /** 730 * Return the {@link Context} this fragment is currently associated with. 731 */ 732 public Context getContext() { 733 return mHost == null ? null : mHost.getContext(); 734 } 735 736 /** 737 * Return the Activity this fragment is currently associated with. 738 */ 739 final public Activity getActivity() { 740 return mHost == null ? null : mHost.getActivity(); 741 } 742 743 /** 744 * Return the host object of this fragment. May return {@code null} if the fragment 745 * isn't currently being hosted. 746 */ 747 @Nullable 748 final public Object getHost() { 749 return mHost == null ? null : mHost.onGetHost(); 750 } 751 752 /** 753 * Return <code>getActivity().getResources()</code>. 754 */ 755 final public Resources getResources() { 756 if (mHost == null) { 757 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 758 } 759 return mHost.getContext().getResources(); 760 } 761 762 /** 763 * Return a localized, styled CharSequence from the application's package's 764 * default string table. 765 * 766 * @param resId Resource id for the CharSequence text 767 */ 768 public final CharSequence getText(@StringRes int resId) { 769 return getResources().getText(resId); 770 } 771 772 /** 773 * Return a localized string from the application's package's 774 * default string table. 775 * 776 * @param resId Resource id for the string 777 */ 778 public final String getString(@StringRes int resId) { 779 return getResources().getString(resId); 780 } 781 782 /** 783 * Return a localized formatted string from the application's package's 784 * default string table, substituting the format arguments as defined in 785 * {@link java.util.Formatter} and {@link java.lang.String#format}. 786 * 787 * @param resId Resource id for the format string 788 * @param formatArgs The format arguments that will be used for substitution. 789 */ 790 791 public final String getString(@StringRes int resId, Object... formatArgs) { 792 return getResources().getString(resId, formatArgs); 793 } 794 795 /** 796 * Return the FragmentManager for interacting with fragments associated 797 * with this fragment's activity. Note that this will be non-null slightly 798 * before {@link #getActivity()}, during the time from when the fragment is 799 * placed in a {@link FragmentTransaction} until it is committed and 800 * attached to its activity. 801 * 802 * <p>If this Fragment is a child of another Fragment, the FragmentManager 803 * returned here will be the parent's {@link #getChildFragmentManager()}. 804 */ 805 final public FragmentManager getFragmentManager() { 806 return mFragmentManager; 807 } 808 809 /** 810 * Return a private FragmentManager for placing and managing Fragments 811 * inside of this Fragment. 812 */ 813 final public FragmentManager getChildFragmentManager() { 814 if (mChildFragmentManager == null) { 815 instantiateChildFragmentManager(); 816 if (mState >= RESUMED) { 817 mChildFragmentManager.dispatchResume(); 818 } else if (mState >= STARTED) { 819 mChildFragmentManager.dispatchStart(); 820 } else if (mState >= ACTIVITY_CREATED) { 821 mChildFragmentManager.dispatchActivityCreated(); 822 } else if (mState >= CREATED) { 823 mChildFragmentManager.dispatchCreate(); 824 } 825 } 826 return mChildFragmentManager; 827 } 828 829 /** 830 * Returns the parent Fragment containing this Fragment. If this Fragment 831 * is attached directly to an Activity, returns null. 832 */ 833 final public Fragment getParentFragment() { 834 return mParentFragment; 835 } 836 837 /** 838 * Return true if the fragment is currently added to its activity. 839 */ 840 final public boolean isAdded() { 841 return mHost != null && mAdded; 842 } 843 844 /** 845 * Return true if the fragment has been explicitly detached from the UI. 846 * That is, {@link FragmentTransaction#detach(Fragment) 847 * FragmentTransaction.detach(Fragment)} has been used on it. 848 */ 849 final public boolean isDetached() { 850 return mDetached; 851 } 852 853 /** 854 * Return true if this fragment is currently being removed from its 855 * activity. This is <em>not</em> whether its activity is finishing, but 856 * rather whether it is in the process of being removed from its activity. 857 */ 858 final public boolean isRemoving() { 859 return mRemoving; 860 } 861 862 /** 863 * Return true if the layout is included as part of an activity view 864 * hierarchy via the <fragment> tag. This will always be true when 865 * fragments are created through the <fragment> tag, <em>except</em> 866 * in the case where an old fragment is restored from a previous state and 867 * it does not appear in the layout of the current state. 868 */ 869 final public boolean isInLayout() { 870 return mInLayout; 871 } 872 873 /** 874 * Return true if the fragment is in the resumed state. This is true 875 * for the duration of {@link #onResume()} and {@link #onPause()} as well. 876 */ 877 final public boolean isResumed() { 878 return mState >= RESUMED; 879 } 880 881 /** 882 * Return true if the fragment is currently visible to the user. This means 883 * it: (1) has been added, (2) has its view attached to the window, and 884 * (3) is not hidden. 885 */ 886 final public boolean isVisible() { 887 return isAdded() && !isHidden() && mView != null 888 && mView.getWindowToken() != null && mView.getVisibility() == View.VISIBLE; 889 } 890 891 /** 892 * Return true if the fragment has been hidden. By default fragments 893 * are shown. You can find out about changes to this state with 894 * {@link #onHiddenChanged}. Note that the hidden state is orthogonal 895 * to other states -- that is, to be visible to the user, a fragment 896 * must be both started and not hidden. 897 */ 898 final public boolean isHidden() { 899 return mHidden; 900 } 901 902 /** 903 * Called when the hidden state (as returned by {@link #isHidden()} of 904 * the fragment has changed. Fragments start out not hidden; this will 905 * be called whenever the fragment changes state from that. 906 * @param hidden True if the fragment is now hidden, false otherwise. 907 */ 908 public void onHiddenChanged(boolean hidden) { 909 } 910 911 /** 912 * Control whether a fragment instance is retained across Activity 913 * re-creation (such as from a configuration change). This can only 914 * be used with fragments not in the back stack. If set, the fragment 915 * lifecycle will be slightly different when an activity is recreated: 916 * <ul> 917 * <li> {@link #onDestroy()} will not be called (but {@link #onDetach()} still 918 * will be, because the fragment is being detached from its current activity). 919 * <li> {@link #onCreate(Bundle)} will not be called since the fragment 920 * is not being re-created. 921 * <li> {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} <b>will</b> 922 * still be called. 923 * </ul> 924 */ 925 public void setRetainInstance(boolean retain) { 926 mRetainInstance = retain; 927 } 928 929 final public boolean getRetainInstance() { 930 return mRetainInstance; 931 } 932 933 /** 934 * Report that this fragment would like to participate in populating 935 * the options menu by receiving a call to {@link #onCreateOptionsMenu} 936 * and related methods. 937 * 938 * @param hasMenu If true, the fragment has menu items to contribute. 939 */ 940 public void setHasOptionsMenu(boolean hasMenu) { 941 if (mHasMenu != hasMenu) { 942 mHasMenu = hasMenu; 943 if (isAdded() && !isHidden()) { 944 mFragmentManager.invalidateOptionsMenu(); 945 } 946 } 947 } 948 949 /** 950 * Set a hint for whether this fragment's menu should be visible. This 951 * is useful if you know that a fragment has been placed in your view 952 * hierarchy so that the user can not currently seen it, so any menu items 953 * it has should also not be shown. 954 * 955 * @param menuVisible The default is true, meaning the fragment's menu will 956 * be shown as usual. If false, the user will not see the menu. 957 */ 958 public void setMenuVisibility(boolean menuVisible) { 959 if (mMenuVisible != menuVisible) { 960 mMenuVisible = menuVisible; 961 if (mHasMenu && isAdded() && !isHidden()) { 962 mFragmentManager.invalidateOptionsMenu(); 963 } 964 } 965 } 966 967 /** 968 * Set a hint to the system about whether this fragment's UI is currently visible 969 * to the user. This hint defaults to true and is persistent across fragment instance 970 * state save and restore. 971 * 972 * <p>An app may set this to false to indicate that the fragment's UI is 973 * scrolled out of visibility or is otherwise not directly visible to the user. 974 * This may be used by the system to prioritize operations such as fragment lifecycle updates 975 * or loader ordering behavior.</p> 976 * 977 * <p><strong>Note:</strong> This method may be called outside of the fragment lifecycle 978 * and thus has no ordering guarantees with regard to fragment lifecycle method calls.</p> 979 * 980 * <p><strong>Note:</strong> Prior to Android N there was a platform bug that could cause 981 * <code>setUserVisibleHint</code> to bring a fragment up to the started state before its 982 * <code>FragmentTransaction</code> had been committed. As some apps relied on this behavior, 983 * it is preserved for apps that declare a <code>targetSdkVersion</code> of 23 or lower.</p> 984 * 985 * @param isVisibleToUser true if this fragment's UI is currently visible to the user (default), 986 * false if it is not. 987 */ 988 public void setUserVisibleHint(boolean isVisibleToUser) { 989 // Prior to Android N we were simply checking if this fragment had a FragmentManager 990 // set before we would trigger a deferred start. Unfortunately this also gets set before 991 // a fragment transaction is committed, so if setUserVisibleHint was called before a 992 // transaction commit, we would start the fragment way too early. FragmentPagerAdapter 993 // triggers this situation. 994 // Unfortunately some apps relied on this timing in overrides of setUserVisibleHint 995 // on their own fragments, and expected, however erroneously, that after a call to 996 // super.setUserVisibleHint their onStart methods had been run. 997 // We preserve this behavior for apps targeting old platform versions below. 998 boolean useBrokenAddedCheck = false; 999 Context context = getContext(); 1000 if (mFragmentManager != null && mFragmentManager.mHost != null) { 1001 context = mFragmentManager.mHost.getContext(); 1002 } 1003 if (context != null) { 1004 useBrokenAddedCheck = context.getApplicationInfo().targetSdkVersion <= VERSION_CODES.M; 1005 } 1006 1007 final boolean performDeferredStart; 1008 if (useBrokenAddedCheck) { 1009 performDeferredStart = !mUserVisibleHint && isVisibleToUser && mState < STARTED 1010 && mFragmentManager != null; 1011 } else { 1012 performDeferredStart = !mUserVisibleHint && isVisibleToUser && mState < STARTED 1013 && mFragmentManager != null && isAdded(); 1014 } 1015 1016 if (performDeferredStart) { 1017 mFragmentManager.performPendingDeferredStart(this); 1018 } 1019 1020 mUserVisibleHint = isVisibleToUser; 1021 mDeferStart = mState < STARTED && !isVisibleToUser; 1022 } 1023 1024 /** 1025 * @return The current value of the user-visible hint on this fragment. 1026 * @see #setUserVisibleHint(boolean) 1027 */ 1028 public boolean getUserVisibleHint() { 1029 return mUserVisibleHint; 1030 } 1031 1032 /** 1033 * Return the LoaderManager for this fragment, creating it if needed. 1034 */ 1035 public LoaderManager getLoaderManager() { 1036 if (mLoaderManager != null) { 1037 return mLoaderManager; 1038 } 1039 if (mHost == null) { 1040 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1041 } 1042 mCheckedForLoaderManager = true; 1043 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, true); 1044 return mLoaderManager; 1045 } 1046 1047 /** 1048 * Call {@link Activity#startActivity(Intent)} from the fragment's 1049 * containing Activity. 1050 * 1051 * @param intent The intent to start. 1052 */ 1053 public void startActivity(Intent intent) { 1054 startActivity(intent, null); 1055 } 1056 1057 /** 1058 * Call {@link Activity#startActivity(Intent, Bundle)} from the fragment's 1059 * containing Activity. 1060 * 1061 * @param intent The intent to start. 1062 * @param options Additional options for how the Activity should be started. 1063 * See {@link android.content.Context#startActivity(Intent, Bundle)} 1064 * Context.startActivity(Intent, Bundle)} for more details. 1065 */ 1066 public void startActivity(Intent intent, Bundle options) { 1067 if (mHost == null) { 1068 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1069 } 1070 if (options != null) { 1071 mHost.onStartActivityFromFragment(this, intent, -1, options); 1072 } else { 1073 // Note we want to go through this call for compatibility with 1074 // applications that may have overridden the method. 1075 mHost.onStartActivityFromFragment(this, intent, -1, null /*options*/); 1076 } 1077 } 1078 1079 /** 1080 * Call {@link Activity#startActivityForResult(Intent, int)} from the fragment's 1081 * containing Activity. 1082 */ 1083 public void startActivityForResult(Intent intent, int requestCode) { 1084 startActivityForResult(intent, requestCode, null); 1085 } 1086 1087 /** 1088 * Call {@link Activity#startActivityForResult(Intent, int, Bundle)} from the fragment's 1089 * containing Activity. 1090 */ 1091 public void startActivityForResult(Intent intent, int requestCode, Bundle options) { 1092 if (mHost == null) { 1093 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1094 } 1095 mHost.onStartActivityFromFragment(this, intent, requestCode, options); 1096 } 1097 1098 /** 1099 * @hide 1100 * Call {@link Activity#startActivityForResultAsUser(Intent, int, UserHandle)} from the 1101 * fragment's containing Activity. 1102 */ 1103 public void startActivityForResultAsUser( 1104 Intent intent, int requestCode, Bundle options, UserHandle user) { 1105 if (mHost == null) { 1106 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1107 } 1108 mHost.onStartActivityAsUserFromFragment(this, intent, requestCode, options, user); 1109 } 1110 1111 /** 1112 * Call {@link Activity#startIntentSenderForResult(IntentSender, int, Intent, int, int, int, 1113 * Bundle)} from the fragment's containing Activity. 1114 */ 1115 public void startIntentSenderForResult(IntentSender intent, int requestCode, 1116 @Nullable Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags, 1117 Bundle options) throws IntentSender.SendIntentException { 1118 if (mHost == null) { 1119 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1120 } 1121 mHost.onStartIntentSenderFromFragment(this, intent, requestCode, fillInIntent, flagsMask, 1122 flagsValues, extraFlags, options); 1123 } 1124 1125 /** 1126 * Receive the result from a previous call to 1127 * {@link #startActivityForResult(Intent, int)}. This follows the 1128 * related Activity API as described there in 1129 * {@link Activity#onActivityResult(int, int, Intent)}. 1130 * 1131 * @param requestCode The integer request code originally supplied to 1132 * startActivityForResult(), allowing you to identify who this 1133 * result came from. 1134 * @param resultCode The integer result code returned by the child activity 1135 * through its setResult(). 1136 * @param data An Intent, which can return result data to the caller 1137 * (various data can be attached to Intent "extras"). 1138 */ 1139 public void onActivityResult(int requestCode, int resultCode, Intent data) { 1140 } 1141 1142 /** 1143 * Requests permissions to be granted to this application. These permissions 1144 * must be requested in your manifest, they should not be granted to your app, 1145 * and they should have protection level {@link android.content.pm.PermissionInfo 1146 * #PROTECTION_DANGEROUS dangerous}, regardless whether they are declared by 1147 * the platform or a third-party app. 1148 * <p> 1149 * Normal permissions {@link android.content.pm.PermissionInfo#PROTECTION_NORMAL} 1150 * are granted at install time if requested in the manifest. Signature permissions 1151 * {@link android.content.pm.PermissionInfo#PROTECTION_SIGNATURE} are granted at 1152 * install time if requested in the manifest and the signature of your app matches 1153 * the signature of the app declaring the permissions. 1154 * </p> 1155 * <p> 1156 * If your app does not have the requested permissions the user will be presented 1157 * with UI for accepting them. After the user has accepted or rejected the 1158 * requested permissions you will receive a callback on {@link 1159 * #onRequestPermissionsResult(int, String[], int[])} reporting whether the 1160 * permissions were granted or not. 1161 * </p> 1162 * <p> 1163 * Note that requesting a permission does not guarantee it will be granted and 1164 * your app should be able to run without having this permission. 1165 * </p> 1166 * <p> 1167 * This method may start an activity allowing the user to choose which permissions 1168 * to grant and which to reject. Hence, you should be prepared that your activity 1169 * may be paused and resumed. Further, granting some permissions may require 1170 * a restart of you application. In such a case, the system will recreate the 1171 * activity stack before delivering the result to {@link 1172 * #onRequestPermissionsResult(int, String[], int[])}. 1173 * </p> 1174 * <p> 1175 * When checking whether you have a permission you should use {@link 1176 * android.content.Context#checkSelfPermission(String)}. 1177 * </p> 1178 * <p> 1179 * Calling this API for permissions already granted to your app would show UI 1180 * to the user to decide whether the app can still hold these permissions. This 1181 * can be useful if the way your app uses data guarded by the permissions 1182 * changes significantly. 1183 * </p> 1184 * <p> 1185 * You cannot request a permission if your activity sets {@link 1186 * android.R.styleable#AndroidManifestActivity_noHistory noHistory} to 1187 * <code>true</code> because in this case the activity would not receive 1188 * result callbacks including {@link #onRequestPermissionsResult(int, String[], int[])}. 1189 * </p> 1190 * <p> 1191 * A sample permissions request looks like this: 1192 * </p> 1193 * <code><pre><p> 1194 * private void showContacts() { 1195 * if (getActivity().checkSelfPermission(Manifest.permission.READ_CONTACTS) 1196 * != PackageManager.PERMISSION_GRANTED) { 1197 * requestPermissions(new String[]{Manifest.permission.READ_CONTACTS}, 1198 * PERMISSIONS_REQUEST_READ_CONTACTS); 1199 * } else { 1200 * doShowContacts(); 1201 * } 1202 * } 1203 * 1204 * {@literal @}Override 1205 * public void onRequestPermissionsResult(int requestCode, String[] permissions, 1206 * int[] grantResults) { 1207 * if (requestCode == PERMISSIONS_REQUEST_READ_CONTACTS 1208 * && grantResults[0] == PackageManager.PERMISSION_GRANTED) { 1209 * doShowContacts(); 1210 * } 1211 * } 1212 * </code></pre></p> 1213 * 1214 * @param permissions The requested permissions. Must me non-null and not empty. 1215 * @param requestCode Application specific request code to match with a result 1216 * reported to {@link #onRequestPermissionsResult(int, String[], int[])}. 1217 * Should be >= 0. 1218 * 1219 * @see #onRequestPermissionsResult(int, String[], int[]) 1220 * @see android.content.Context#checkSelfPermission(String) 1221 */ 1222 public final void requestPermissions(@NonNull String[] permissions, int requestCode) { 1223 if (mHost == null) { 1224 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1225 } 1226 mHost.onRequestPermissionsFromFragment(this, permissions,requestCode); 1227 } 1228 1229 /** 1230 * Callback for the result from requesting permissions. This method 1231 * is invoked for every call on {@link #requestPermissions(String[], int)}. 1232 * <p> 1233 * <strong>Note:</strong> It is possible that the permissions request interaction 1234 * with the user is interrupted. In this case you will receive empty permissions 1235 * and results arrays which should be treated as a cancellation. 1236 * </p> 1237 * 1238 * @param requestCode The request code passed in {@link #requestPermissions(String[], int)}. 1239 * @param permissions The requested permissions. Never null. 1240 * @param grantResults The grant results for the corresponding permissions 1241 * which is either {@link android.content.pm.PackageManager#PERMISSION_GRANTED} 1242 * or {@link android.content.pm.PackageManager#PERMISSION_DENIED}. Never null. 1243 * 1244 * @see #requestPermissions(String[], int) 1245 */ 1246 public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, 1247 @NonNull int[] grantResults) { 1248 /* callback - do nothing */ 1249 } 1250 1251 /** 1252 * Gets whether you should show UI with rationale for requesting a permission. 1253 * You should do this only if you do not have the permission and the context in 1254 * which the permission is requested does not clearly communicate to the user 1255 * what would be the benefit from granting this permission. 1256 * <p> 1257 * For example, if you write a camera app, requesting the camera permission 1258 * would be expected by the user and no rationale for why it is requested is 1259 * needed. If however, the app needs location for tagging photos then a non-tech 1260 * savvy user may wonder how location is related to taking photos. In this case 1261 * you may choose to show UI with rationale of requesting this permission. 1262 * </p> 1263 * 1264 * @param permission A permission your app wants to request. 1265 * @return Whether you can show permission rationale UI. 1266 * 1267 * @see Context#checkSelfPermission(String) 1268 * @see #requestPermissions(String[], int) 1269 * @see #onRequestPermissionsResult(int, String[], int[]) 1270 */ 1271 public boolean shouldShowRequestPermissionRationale(@NonNull String permission) { 1272 if (mHost != null) { 1273 return mHost.getContext().getPackageManager() 1274 .shouldShowRequestPermissionRationale(permission); 1275 } 1276 return false; 1277 } 1278 1279 /** 1280 * Returns the LayoutInflater used to inflate Views of this Fragment. The default 1281 * implementation will throw an exception if the Fragment is not attached. 1282 * 1283 * @return The LayoutInflater used to inflate Views of this Fragment. 1284 */ 1285 public LayoutInflater onGetLayoutInflater(Bundle savedInstanceState) { 1286 if (mHost == null) { 1287 throw new IllegalStateException("onGetLayoutInflater() cannot be executed until the " 1288 + "Fragment is attached to the FragmentManager."); 1289 } 1290 final LayoutInflater result = mHost.onGetLayoutInflater(); 1291 if (mHost.onUseFragmentManagerInflaterFactory()) { 1292 getChildFragmentManager(); // Init if needed; use raw implementation below. 1293 result.setPrivateFactory(mChildFragmentManager.getLayoutInflaterFactory()); 1294 } 1295 return result; 1296 } 1297 1298 /** 1299 * Returns the cached LayoutInflater used to inflate Views of this Fragment. If 1300 * {@link #onGetLayoutInflater(Bundle)} has not been called {@link #onGetLayoutInflater(Bundle)} 1301 * will be called with a {@code null} argument and that value will be cached. 1302 * <p> 1303 * The cached LayoutInflater will be replaced immediately prior to 1304 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} and cleared immediately after 1305 * {@link #onDetach()}. 1306 * 1307 * @return The LayoutInflater used to inflate Views of this Fragment. 1308 */ 1309 public final LayoutInflater getLayoutInflater() { 1310 if (mLayoutInflater == null) { 1311 return performGetLayoutInflater(null); 1312 } 1313 return mLayoutInflater; 1314 } 1315 1316 /** 1317 * Calls {@link #onGetLayoutInflater(Bundle)} and caches the result for use by 1318 * {@link #getLayoutInflater()}. 1319 * 1320 * @param savedInstanceState If the fragment is being re-created from 1321 * a previous saved state, this is the state. 1322 * @return The LayoutInflater used to inflate Views of this Fragment. 1323 */ 1324 LayoutInflater performGetLayoutInflater(Bundle savedInstanceState) { 1325 LayoutInflater layoutInflater = onGetLayoutInflater(savedInstanceState); 1326 mLayoutInflater = layoutInflater; 1327 return mLayoutInflater; 1328 } 1329 1330 /** 1331 * @deprecated Use {@link #onInflate(Context, AttributeSet, Bundle)} instead. 1332 */ 1333 @Deprecated 1334 @CallSuper 1335 public void onInflate(AttributeSet attrs, Bundle savedInstanceState) { 1336 mCalled = true; 1337 } 1338 1339 /** 1340 * Called when a fragment is being created as part of a view layout 1341 * inflation, typically from setting the content view of an activity. This 1342 * may be called immediately after the fragment is created from a <fragment> 1343 * tag in a layout file. Note this is <em>before</em> the fragment's 1344 * {@link #onAttach(Activity)} has been called; all you should do here is 1345 * parse the attributes and save them away. 1346 * 1347 * <p>This is called every time the fragment is inflated, even if it is 1348 * being inflated into a new instance with saved state. It typically makes 1349 * sense to re-parse the parameters each time, to allow them to change with 1350 * different configurations.</p> 1351 * 1352 * <p>Here is a typical implementation of a fragment that can take parameters 1353 * both through attributes supplied here as well from {@link #getArguments()}:</p> 1354 * 1355 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1356 * fragment} 1357 * 1358 * <p>Note that parsing the XML attributes uses a "styleable" resource. The 1359 * declaration for the styleable used here is:</p> 1360 * 1361 * {@sample development/samples/ApiDemos/res/values/attrs.xml fragment_arguments} 1362 * 1363 * <p>The fragment can then be declared within its activity's content layout 1364 * through a tag like this:</p> 1365 * 1366 * {@sample development/samples/ApiDemos/res/layout/fragment_arguments.xml from_attributes} 1367 * 1368 * <p>This fragment can also be created dynamically from arguments given 1369 * at runtime in the arguments Bundle; here is an example of doing so at 1370 * creation of the containing activity:</p> 1371 * 1372 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1373 * create} 1374 * 1375 * @param context The Context that is inflating this fragment. 1376 * @param attrs The attributes at the tag where the fragment is 1377 * being created. 1378 * @param savedInstanceState If the fragment is being re-created from 1379 * a previous saved state, this is the state. 1380 */ 1381 @CallSuper 1382 public void onInflate(Context context, AttributeSet attrs, Bundle savedInstanceState) { 1383 onInflate(attrs, savedInstanceState); 1384 mCalled = true; 1385 1386 TypedArray a = context.obtainStyledAttributes(attrs, 1387 com.android.internal.R.styleable.Fragment); 1388 setEnterTransition(loadTransition(context, a, getEnterTransition(), null, 1389 com.android.internal.R.styleable.Fragment_fragmentEnterTransition)); 1390 setReturnTransition(loadTransition(context, a, getReturnTransition(), 1391 USE_DEFAULT_TRANSITION, 1392 com.android.internal.R.styleable.Fragment_fragmentReturnTransition)); 1393 setExitTransition(loadTransition(context, a, getExitTransition(), null, 1394 com.android.internal.R.styleable.Fragment_fragmentExitTransition)); 1395 1396 setReenterTransition(loadTransition(context, a, getReenterTransition(), 1397 USE_DEFAULT_TRANSITION, 1398 com.android.internal.R.styleable.Fragment_fragmentReenterTransition)); 1399 setSharedElementEnterTransition(loadTransition(context, a, 1400 getSharedElementEnterTransition(), null, 1401 com.android.internal.R.styleable.Fragment_fragmentSharedElementEnterTransition)); 1402 setSharedElementReturnTransition(loadTransition(context, a, 1403 getSharedElementReturnTransition(), USE_DEFAULT_TRANSITION, 1404 com.android.internal.R.styleable.Fragment_fragmentSharedElementReturnTransition)); 1405 boolean isEnterSet; 1406 boolean isReturnSet; 1407 if (mAnimationInfo == null) { 1408 isEnterSet = false; 1409 isReturnSet = false; 1410 } else { 1411 isEnterSet = mAnimationInfo.mAllowEnterTransitionOverlap != null; 1412 isReturnSet = mAnimationInfo.mAllowReturnTransitionOverlap != null; 1413 } 1414 if (!isEnterSet) { 1415 setAllowEnterTransitionOverlap(a.getBoolean( 1416 com.android.internal.R.styleable.Fragment_fragmentAllowEnterTransitionOverlap, 1417 true)); 1418 } 1419 if (!isReturnSet) { 1420 setAllowReturnTransitionOverlap(a.getBoolean( 1421 com.android.internal.R.styleable.Fragment_fragmentAllowReturnTransitionOverlap, 1422 true)); 1423 } 1424 a.recycle(); 1425 1426 final Activity hostActivity = mHost == null ? null : mHost.getActivity(); 1427 if (hostActivity != null) { 1428 mCalled = false; 1429 onInflate(hostActivity, attrs, savedInstanceState); 1430 } 1431 } 1432 1433 /** 1434 * @deprecated Use {@link #onInflate(Context, AttributeSet, Bundle)} instead. 1435 */ 1436 @Deprecated 1437 @CallSuper 1438 public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) { 1439 mCalled = true; 1440 } 1441 1442 /** 1443 * Called when a fragment is attached as a child of this fragment. 1444 * 1445 * <p>This is called after the attached fragment's <code>onAttach</code> and before 1446 * the attached fragment's <code>onCreate</code> if the fragment has not yet had a previous 1447 * call to <code>onCreate</code>.</p> 1448 * 1449 * @param childFragment child fragment being attached 1450 */ 1451 public void onAttachFragment(Fragment childFragment) { 1452 } 1453 1454 /** 1455 * Called when a fragment is first attached to its context. 1456 * {@link #onCreate(Bundle)} will be called after this. 1457 */ 1458 @CallSuper 1459 public void onAttach(Context context) { 1460 mCalled = true; 1461 final Activity hostActivity = mHost == null ? null : mHost.getActivity(); 1462 if (hostActivity != null) { 1463 mCalled = false; 1464 onAttach(hostActivity); 1465 } 1466 } 1467 1468 /** 1469 * @deprecated Use {@link #onAttach(Context)} instead. 1470 */ 1471 @Deprecated 1472 @CallSuper 1473 public void onAttach(Activity activity) { 1474 mCalled = true; 1475 } 1476 1477 /** 1478 * Called when a fragment loads an animation. 1479 */ 1480 public Animator onCreateAnimator(int transit, boolean enter, int nextAnim) { 1481 return null; 1482 } 1483 1484 /** 1485 * Called to do initial creation of a fragment. This is called after 1486 * {@link #onAttach(Activity)} and before 1487 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, but is not called if the fragment 1488 * instance is retained across Activity re-creation (see {@link #setRetainInstance(boolean)}). 1489 * 1490 * <p>Note that this can be called while the fragment's activity is 1491 * still in the process of being created. As such, you can not rely 1492 * on things like the activity's content view hierarchy being initialized 1493 * at this point. If you want to do work once the activity itself is 1494 * created, see {@link #onActivityCreated(Bundle)}. 1495 * 1496 * <p>If your app's <code>targetSdkVersion</code> is {@link android.os.Build.VERSION_CODES#M} 1497 * or lower, child fragments being restored from the savedInstanceState are restored after 1498 * <code>onCreate</code> returns. When targeting {@link android.os.Build.VERSION_CODES#N} or 1499 * above and running on an N or newer platform version 1500 * they are restored by <code>Fragment.onCreate</code>.</p> 1501 * 1502 * @param savedInstanceState If the fragment is being re-created from 1503 * a previous saved state, this is the state. 1504 */ 1505 @CallSuper 1506 public void onCreate(@Nullable Bundle savedInstanceState) { 1507 mCalled = true; 1508 final Context context = getContext(); 1509 final int version = context != null ? context.getApplicationInfo().targetSdkVersion : 0; 1510 if (version >= Build.VERSION_CODES.N) { 1511 restoreChildFragmentState(savedInstanceState, true); 1512 if (mChildFragmentManager != null 1513 && !mChildFragmentManager.isStateAtLeast(Fragment.CREATED)) { 1514 mChildFragmentManager.dispatchCreate(); 1515 } 1516 } 1517 } 1518 1519 void restoreChildFragmentState(@Nullable Bundle savedInstanceState, boolean provideNonConfig) { 1520 if (savedInstanceState != null) { 1521 Parcelable p = savedInstanceState.getParcelable(Activity.FRAGMENTS_TAG); 1522 if (p != null) { 1523 if (mChildFragmentManager == null) { 1524 instantiateChildFragmentManager(); 1525 } 1526 mChildFragmentManager.restoreAllState(p, provideNonConfig ? mChildNonConfig : null); 1527 mChildNonConfig = null; 1528 mChildFragmentManager.dispatchCreate(); 1529 } 1530 } 1531 } 1532 1533 /** 1534 * Called to have the fragment instantiate its user interface view. 1535 * This is optional, and non-graphical fragments can return null (which 1536 * is the default implementation). This will be called between 1537 * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}. 1538 * 1539 * <p>If you return a View from here, you will later be called in 1540 * {@link #onDestroyView} when the view is being released. 1541 * 1542 * @param inflater The LayoutInflater object that can be used to inflate 1543 * any views in the fragment, 1544 * @param container If non-null, this is the parent view that the fragment's 1545 * UI should be attached to. The fragment should not add the view itself, 1546 * but this can be used to generate the LayoutParams of the view. 1547 * @param savedInstanceState If non-null, this fragment is being re-constructed 1548 * from a previous saved state as given here. 1549 * 1550 * @return Return the View for the fragment's UI, or null. 1551 */ 1552 @Nullable 1553 public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, 1554 Bundle savedInstanceState) { 1555 return null; 1556 } 1557 1558 /** 1559 * Called immediately after {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} 1560 * has returned, but before any saved state has been restored in to the view. 1561 * This gives subclasses a chance to initialize themselves once 1562 * they know their view hierarchy has been completely created. The fragment's 1563 * view hierarchy is not however attached to its parent at this point. 1564 * @param view The View returned by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 1565 * @param savedInstanceState If non-null, this fragment is being re-constructed 1566 * from a previous saved state as given here. 1567 */ 1568 public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { 1569 } 1570 1571 /** 1572 * Get the root view for the fragment's layout (the one returned by {@link #onCreateView}), 1573 * if provided. 1574 * 1575 * @return The fragment's root view, or null if it has no layout. 1576 */ 1577 @Nullable 1578 public View getView() { 1579 return mView; 1580 } 1581 1582 /** 1583 * Called when the fragment's activity has been created and this 1584 * fragment's view hierarchy instantiated. It can be used to do final 1585 * initialization once these pieces are in place, such as retrieving 1586 * views or restoring state. It is also useful for fragments that use 1587 * {@link #setRetainInstance(boolean)} to retain their instance, 1588 * as this callback tells the fragment when it is fully associated with 1589 * the new activity instance. This is called after {@link #onCreateView} 1590 * and before {@link #onViewStateRestored(Bundle)}. 1591 * 1592 * @param savedInstanceState If the fragment is being re-created from 1593 * a previous saved state, this is the state. 1594 */ 1595 @CallSuper 1596 public void onActivityCreated(@Nullable Bundle savedInstanceState) { 1597 mCalled = true; 1598 } 1599 1600 /** 1601 * Called when all saved state has been restored into the view hierarchy 1602 * of the fragment. This can be used to do initialization based on saved 1603 * state that you are letting the view hierarchy track itself, such as 1604 * whether check box widgets are currently checked. This is called 1605 * after {@link #onActivityCreated(Bundle)} and before 1606 * {@link #onStart()}. 1607 * 1608 * @param savedInstanceState If the fragment is being re-created from 1609 * a previous saved state, this is the state. 1610 */ 1611 @CallSuper 1612 public void onViewStateRestored(Bundle savedInstanceState) { 1613 mCalled = true; 1614 } 1615 1616 /** 1617 * Called when the Fragment is visible to the user. This is generally 1618 * tied to {@link Activity#onStart() Activity.onStart} of the containing 1619 * Activity's lifecycle. 1620 */ 1621 @CallSuper 1622 public void onStart() { 1623 mCalled = true; 1624 1625 if (!mLoadersStarted) { 1626 mLoadersStarted = true; 1627 if (!mCheckedForLoaderManager) { 1628 mCheckedForLoaderManager = true; 1629 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 1630 } else if (mLoaderManager != null) { 1631 mLoaderManager.doStart(); 1632 } 1633 } 1634 } 1635 1636 /** 1637 * Called when the fragment is visible to the user and actively running. 1638 * This is generally 1639 * tied to {@link Activity#onResume() Activity.onResume} of the containing 1640 * Activity's lifecycle. 1641 */ 1642 @CallSuper 1643 public void onResume() { 1644 mCalled = true; 1645 } 1646 1647 /** 1648 * Called to ask the fragment to save its current dynamic state, so it 1649 * can later be reconstructed in a new instance of its process is 1650 * restarted. If a new instance of the fragment later needs to be 1651 * created, the data you place in the Bundle here will be available 1652 * in the Bundle given to {@link #onCreate(Bundle)}, 1653 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, and 1654 * {@link #onActivityCreated(Bundle)}. 1655 * 1656 * <p>This corresponds to {@link Activity#onSaveInstanceState(Bundle) 1657 * Activity.onSaveInstanceState(Bundle)} and most of the discussion there 1658 * applies here as well. Note however: <em>this method may be called 1659 * at any time before {@link #onDestroy()}</em>. There are many situations 1660 * where a fragment may be mostly torn down (such as when placed on the 1661 * back stack with no UI showing), but its state will not be saved until 1662 * its owning activity actually needs to save its state. 1663 * 1664 * @param outState Bundle in which to place your saved state. 1665 */ 1666 public void onSaveInstanceState(Bundle outState) { 1667 } 1668 1669 /** 1670 * Called when the Fragment's activity changes from fullscreen mode to multi-window mode and 1671 * visa-versa. This is generally tied to {@link Activity#onMultiWindowModeChanged} of the 1672 * containing Activity. This method provides the same configuration that will be sent in the 1673 * following {@link #onConfigurationChanged(Configuration)} call after the activity enters this 1674 * mode. 1675 * 1676 * @param isInMultiWindowMode True if the activity is in multi-window mode. 1677 * @param newConfig The new configuration of the activity with the state 1678 * {@param isInMultiWindowMode}. 1679 */ 1680 public void onMultiWindowModeChanged(boolean isInMultiWindowMode, Configuration newConfig) { 1681 onMultiWindowModeChanged(isInMultiWindowMode); 1682 } 1683 1684 /** 1685 * Called when the Fragment's activity changes from fullscreen mode to multi-window mode and 1686 * visa-versa. This is generally tied to {@link Activity#onMultiWindowModeChanged} of the 1687 * containing Activity. 1688 * 1689 * @param isInMultiWindowMode True if the activity is in multi-window mode. 1690 * 1691 * @deprecated Use {@link #onMultiWindowModeChanged(boolean, Configuration)} instead. 1692 */ 1693 @Deprecated 1694 public void onMultiWindowModeChanged(boolean isInMultiWindowMode) { 1695 } 1696 1697 /** 1698 * Called by the system when the activity changes to and from picture-in-picture mode. This is 1699 * generally tied to {@link Activity#onPictureInPictureModeChanged} of the containing Activity. 1700 * This method provides the same configuration that will be sent in the following 1701 * {@link #onConfigurationChanged(Configuration)} call after the activity enters this mode. 1702 * 1703 * @param isInPictureInPictureMode True if the activity is in picture-in-picture mode. 1704 * @param newConfig The new configuration of the activity with the state 1705 * {@param isInPictureInPictureMode}. 1706 */ 1707 public void onPictureInPictureModeChanged(boolean isInPictureInPictureMode, 1708 Configuration newConfig) { 1709 onPictureInPictureModeChanged(isInPictureInPictureMode); 1710 } 1711 1712 /** 1713 * Called by the system when the activity changes to and from picture-in-picture mode. This is 1714 * generally tied to {@link Activity#onPictureInPictureModeChanged} of the containing Activity. 1715 * 1716 * @param isInPictureInPictureMode True if the activity is in picture-in-picture mode. 1717 * 1718 * @deprecated Use {@link #onPictureInPictureModeChanged(boolean, Configuration)} instead. 1719 */ 1720 @Deprecated 1721 public void onPictureInPictureModeChanged(boolean isInPictureInPictureMode) { 1722 } 1723 1724 @CallSuper 1725 public void onConfigurationChanged(Configuration newConfig) { 1726 mCalled = true; 1727 } 1728 1729 /** 1730 * Called when the Fragment is no longer resumed. This is generally 1731 * tied to {@link Activity#onPause() Activity.onPause} of the containing 1732 * Activity's lifecycle. 1733 */ 1734 @CallSuper 1735 public void onPause() { 1736 mCalled = true; 1737 } 1738 1739 /** 1740 * Called when the Fragment is no longer started. This is generally 1741 * tied to {@link Activity#onStop() Activity.onStop} of the containing 1742 * Activity's lifecycle. 1743 */ 1744 @CallSuper 1745 public void onStop() { 1746 mCalled = true; 1747 } 1748 1749 @CallSuper 1750 public void onLowMemory() { 1751 mCalled = true; 1752 } 1753 1754 @CallSuper 1755 public void onTrimMemory(int level) { 1756 mCalled = true; 1757 } 1758 1759 /** 1760 * Called when the view previously created by {@link #onCreateView} has 1761 * been detached from the fragment. The next time the fragment needs 1762 * to be displayed, a new view will be created. This is called 1763 * after {@link #onStop()} and before {@link #onDestroy()}. It is called 1764 * <em>regardless</em> of whether {@link #onCreateView} returned a 1765 * non-null view. Internally it is called after the view's state has 1766 * been saved but before it has been removed from its parent. 1767 */ 1768 @CallSuper 1769 public void onDestroyView() { 1770 mCalled = true; 1771 } 1772 1773 /** 1774 * Called when the fragment is no longer in use. This is called 1775 * after {@link #onStop()} and before {@link #onDetach()}. 1776 */ 1777 @CallSuper 1778 public void onDestroy() { 1779 mCalled = true; 1780 //Log.v("foo", "onDestroy: mCheckedForLoaderManager=" + mCheckedForLoaderManager 1781 // + " mLoaderManager=" + mLoaderManager); 1782 if (!mCheckedForLoaderManager) { 1783 mCheckedForLoaderManager = true; 1784 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 1785 } 1786 if (mLoaderManager != null) { 1787 mLoaderManager.doDestroy(); 1788 } 1789 } 1790 1791 /** 1792 * Called by the fragment manager once this fragment has been removed, 1793 * so that we don't have any left-over state if the application decides 1794 * to re-use the instance. This only clears state that the framework 1795 * internally manages, not things the application sets. 1796 */ 1797 void initState() { 1798 mIndex = -1; 1799 mWho = null; 1800 mAdded = false; 1801 mRemoving = false; 1802 mFromLayout = false; 1803 mInLayout = false; 1804 mRestored = false; 1805 mBackStackNesting = 0; 1806 mFragmentManager = null; 1807 mChildFragmentManager = null; 1808 mHost = null; 1809 mFragmentId = 0; 1810 mContainerId = 0; 1811 mTag = null; 1812 mHidden = false; 1813 mDetached = false; 1814 mRetaining = false; 1815 mLoaderManager = null; 1816 mLoadersStarted = false; 1817 mCheckedForLoaderManager = false; 1818 } 1819 1820 /** 1821 * Called when the fragment is no longer attached to its activity. This is called after 1822 * {@link #onDestroy()}, except in the cases where the fragment instance is retained across 1823 * Activity re-creation (see {@link #setRetainInstance(boolean)}), in which case it is called 1824 * after {@link #onStop()}. 1825 */ 1826 @CallSuper 1827 public void onDetach() { 1828 mCalled = true; 1829 } 1830 1831 /** 1832 * Initialize the contents of the Activity's standard options menu. You 1833 * should place your menu items in to <var>menu</var>. For this method 1834 * to be called, you must have first called {@link #setHasOptionsMenu}. See 1835 * {@link Activity#onCreateOptionsMenu(Menu) Activity.onCreateOptionsMenu} 1836 * for more information. 1837 * 1838 * @param menu The options menu in which you place your items. 1839 * 1840 * @see #setHasOptionsMenu 1841 * @see #onPrepareOptionsMenu 1842 * @see #onOptionsItemSelected 1843 */ 1844 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 1845 } 1846 1847 /** 1848 * Prepare the Screen's standard options menu to be displayed. This is 1849 * called right before the menu is shown, every time it is shown. You can 1850 * use this method to efficiently enable/disable items or otherwise 1851 * dynamically modify the contents. See 1852 * {@link Activity#onPrepareOptionsMenu(Menu) Activity.onPrepareOptionsMenu} 1853 * for more information. 1854 * 1855 * @param menu The options menu as last shown or first initialized by 1856 * onCreateOptionsMenu(). 1857 * 1858 * @see #setHasOptionsMenu 1859 * @see #onCreateOptionsMenu 1860 */ 1861 public void onPrepareOptionsMenu(Menu menu) { 1862 } 1863 1864 /** 1865 * Called when this fragment's option menu items are no longer being 1866 * included in the overall options menu. Receiving this call means that 1867 * the menu needed to be rebuilt, but this fragment's items were not 1868 * included in the newly built menu (its {@link #onCreateOptionsMenu(Menu, MenuInflater)} 1869 * was not called). 1870 */ 1871 public void onDestroyOptionsMenu() { 1872 } 1873 1874 /** 1875 * This hook is called whenever an item in your options menu is selected. 1876 * The default implementation simply returns false to have the normal 1877 * processing happen (calling the item's Runnable or sending a message to 1878 * its Handler as appropriate). You can use this method for any items 1879 * for which you would like to do processing without those other 1880 * facilities. 1881 * 1882 * <p>Derived classes should call through to the base class for it to 1883 * perform the default menu handling. 1884 * 1885 * @param item The menu item that was selected. 1886 * 1887 * @return boolean Return false to allow normal menu processing to 1888 * proceed, true to consume it here. 1889 * 1890 * @see #onCreateOptionsMenu 1891 */ 1892 public boolean onOptionsItemSelected(MenuItem item) { 1893 return false; 1894 } 1895 1896 /** 1897 * This hook is called whenever the options menu is being closed (either by the user canceling 1898 * the menu with the back/menu button, or when an item is selected). 1899 * 1900 * @param menu The options menu as last shown or first initialized by 1901 * onCreateOptionsMenu(). 1902 */ 1903 public void onOptionsMenuClosed(Menu menu) { 1904 } 1905 1906 /** 1907 * Called when a context menu for the {@code view} is about to be shown. 1908 * Unlike {@link #onCreateOptionsMenu}, this will be called every 1909 * time the context menu is about to be shown and should be populated for 1910 * the view (or item inside the view for {@link AdapterView} subclasses, 1911 * this can be found in the {@code menuInfo})). 1912 * <p> 1913 * Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an 1914 * item has been selected. 1915 * <p> 1916 * The default implementation calls up to 1917 * {@link Activity#onCreateContextMenu Activity.onCreateContextMenu}, though 1918 * you can not call this implementation if you don't want that behavior. 1919 * <p> 1920 * It is not safe to hold onto the context menu after this method returns. 1921 * {@inheritDoc} 1922 */ 1923 public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { 1924 getActivity().onCreateContextMenu(menu, v, menuInfo); 1925 } 1926 1927 /** 1928 * Registers a context menu to be shown for the given view (multiple views 1929 * can show the context menu). This method will set the 1930 * {@link OnCreateContextMenuListener} on the view to this fragment, so 1931 * {@link #onCreateContextMenu(ContextMenu, View, ContextMenuInfo)} will be 1932 * called when it is time to show the context menu. 1933 * 1934 * @see #unregisterForContextMenu(View) 1935 * @param view The view that should show a context menu. 1936 */ 1937 public void registerForContextMenu(View view) { 1938 view.setOnCreateContextMenuListener(this); 1939 } 1940 1941 /** 1942 * Prevents a context menu to be shown for the given view. This method will 1943 * remove the {@link OnCreateContextMenuListener} on the view. 1944 * 1945 * @see #registerForContextMenu(View) 1946 * @param view The view that should stop showing a context menu. 1947 */ 1948 public void unregisterForContextMenu(View view) { 1949 view.setOnCreateContextMenuListener(null); 1950 } 1951 1952 /** 1953 * This hook is called whenever an item in a context menu is selected. The 1954 * default implementation simply returns false to have the normal processing 1955 * happen (calling the item's Runnable or sending a message to its Handler 1956 * as appropriate). You can use this method for any items for which you 1957 * would like to do processing without those other facilities. 1958 * <p> 1959 * Use {@link MenuItem#getMenuInfo()} to get extra information set by the 1960 * View that added this menu item. 1961 * <p> 1962 * Derived classes should call through to the base class for it to perform 1963 * the default menu handling. 1964 * 1965 * @param item The context menu item that was selected. 1966 * @return boolean Return false to allow normal context menu processing to 1967 * proceed, true to consume it here. 1968 */ 1969 public boolean onContextItemSelected(MenuItem item) { 1970 return false; 1971 } 1972 1973 /** 1974 * When custom transitions are used with Fragments, the enter transition callback 1975 * is called when this Fragment is attached or detached when not popping the back stack. 1976 * 1977 * @param callback Used to manipulate the shared element transitions on this Fragment 1978 * when added not as a pop from the back stack. 1979 */ 1980 public void setEnterSharedElementCallback(SharedElementCallback callback) { 1981 if (callback == null) { 1982 if (mAnimationInfo == null) { 1983 return; // already a null callback 1984 } 1985 callback = SharedElementCallback.NULL_CALLBACK; 1986 } 1987 ensureAnimationInfo().mEnterTransitionCallback = callback; 1988 } 1989 1990 /** 1991 * When custom transitions are used with Fragments, the exit transition callback 1992 * is called when this Fragment is attached or detached when popping the back stack. 1993 * 1994 * @param callback Used to manipulate the shared element transitions on this Fragment 1995 * when added as a pop from the back stack. 1996 */ 1997 public void setExitSharedElementCallback(SharedElementCallback callback) { 1998 if (callback == null) { 1999 if (mAnimationInfo == null) { 2000 return; // already a null callback 2001 } 2002 callback = SharedElementCallback.NULL_CALLBACK; 2003 } 2004 ensureAnimationInfo().mExitTransitionCallback = callback; 2005 } 2006 2007 /** 2008 * Sets the Transition that will be used to move Views into the initial scene. The entering 2009 * Views will be those that are regular Views or ViewGroups that have 2010 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2011 * {@link android.transition.Visibility} as entering is governed by changing visibility from 2012 * {@link View#INVISIBLE} to {@link View#VISIBLE}. If <code>transition</code> is null, 2013 * entering Views will remain unaffected. 2014 * 2015 * @param transition The Transition to use to move Views into the initial Scene. 2016 * @attr ref android.R.styleable#Fragment_fragmentEnterTransition 2017 */ 2018 public void setEnterTransition(Transition transition) { 2019 if (shouldChangeTransition(transition, null)) { 2020 ensureAnimationInfo().mEnterTransition = transition; 2021 } 2022 } 2023 2024 /** 2025 * Returns the Transition that will be used to move Views into the initial scene. The entering 2026 * Views will be those that are regular Views or ViewGroups that have 2027 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2028 * {@link android.transition.Visibility} as entering is governed by changing visibility from 2029 * {@link View#INVISIBLE} to {@link View#VISIBLE}. 2030 * 2031 * @return the Transition to use to move Views into the initial Scene. 2032 * @attr ref android.R.styleable#Fragment_fragmentEnterTransition 2033 */ 2034 public Transition getEnterTransition() { 2035 if (mAnimationInfo == null) { 2036 return null; 2037 } 2038 return mAnimationInfo.mEnterTransition; 2039 } 2040 2041 /** 2042 * Sets the Transition that will be used to move Views out of the scene when the Fragment is 2043 * preparing to be removed, hidden, or detached because of popping the back stack. The exiting 2044 * Views will be those that are regular Views or ViewGroups that have 2045 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2046 * {@link android.transition.Visibility} as entering is governed by changing visibility from 2047 * {@link View#VISIBLE} to {@link View#INVISIBLE}. If <code>transition</code> is null, 2048 * entering Views will remain unaffected. If nothing is set, the default will be to 2049 * use the same value as set in {@link #setEnterTransition(android.transition.Transition)}. 2050 * 2051 * @param transition The Transition to use to move Views out of the Scene when the Fragment 2052 * is preparing to close. 2053 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 2054 */ 2055 public void setReturnTransition(Transition transition) { 2056 if (shouldChangeTransition(transition, USE_DEFAULT_TRANSITION)) { 2057 ensureAnimationInfo().mReturnTransition = transition; 2058 } 2059 } 2060 2061 /** 2062 * Returns the Transition that will be used to move Views out of the scene when the Fragment is 2063 * preparing to be removed, hidden, or detached because of popping the back stack. The exiting 2064 * Views will be those that are regular Views or ViewGroups that have 2065 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2066 * {@link android.transition.Visibility} as entering is governed by changing visibility from 2067 * {@link View#VISIBLE} to {@link View#INVISIBLE}. If <code>transition</code> is null, 2068 * entering Views will remain unaffected. 2069 * 2070 * @return the Transition to use to move Views out of the Scene when the Fragment 2071 * is preparing to close. 2072 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 2073 */ 2074 public Transition getReturnTransition() { 2075 if (mAnimationInfo == null) { 2076 return null; 2077 } 2078 return mAnimationInfo.mReturnTransition == USE_DEFAULT_TRANSITION ? getEnterTransition() 2079 : mAnimationInfo.mReturnTransition; 2080 } 2081 2082 /** 2083 * Sets the Transition that will be used to move Views out of the scene when the 2084 * fragment is removed, hidden, or detached when not popping the back stack. 2085 * The exiting Views will be those that are regular Views or ViewGroups that 2086 * have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2087 * {@link android.transition.Visibility} as exiting is governed by changing visibility 2088 * from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, the views will 2089 * remain unaffected. 2090 * 2091 * @param transition The Transition to use to move Views out of the Scene when the Fragment 2092 * is being closed not due to popping the back stack. 2093 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 2094 */ 2095 public void setExitTransition(Transition transition) { 2096 if (shouldChangeTransition(transition, null)) { 2097 ensureAnimationInfo().mExitTransition = transition; 2098 } 2099 } 2100 2101 /** 2102 * Returns the Transition that will be used to move Views out of the scene when the 2103 * fragment is removed, hidden, or detached when not popping the back stack. 2104 * The exiting Views will be those that are regular Views or ViewGroups that 2105 * have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 2106 * {@link android.transition.Visibility} as exiting is governed by changing visibility 2107 * from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, the views will 2108 * remain unaffected. 2109 * 2110 * @return the Transition to use to move Views out of the Scene when the Fragment 2111 * is being closed not due to popping the back stack. 2112 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 2113 */ 2114 public Transition getExitTransition() { 2115 if (mAnimationInfo == null) { 2116 return null; 2117 } 2118 return mAnimationInfo.mExitTransition; 2119 } 2120 2121 /** 2122 * Sets the Transition that will be used to move Views in to the scene when returning due 2123 * to popping a back stack. The entering Views will be those that are regular Views 2124 * or ViewGroups that have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions 2125 * will extend {@link android.transition.Visibility} as exiting is governed by changing 2126 * visibility from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, 2127 * the views will remain unaffected. If nothing is set, the default will be to use the same 2128 * transition as {@link #setExitTransition(android.transition.Transition)}. 2129 * 2130 * @param transition The Transition to use to move Views into the scene when reentering from a 2131 * previously-started Activity. 2132 * @attr ref android.R.styleable#Fragment_fragmentReenterTransition 2133 */ 2134 public void setReenterTransition(Transition transition) { 2135 if (shouldChangeTransition(transition, USE_DEFAULT_TRANSITION)) { 2136 ensureAnimationInfo().mReenterTransition = transition; 2137 } 2138 } 2139 2140 /** 2141 * Returns the Transition that will be used to move Views in to the scene when returning due 2142 * to popping a back stack. The entering Views will be those that are regular Views 2143 * or ViewGroups that have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions 2144 * will extend {@link android.transition.Visibility} as exiting is governed by changing 2145 * visibility from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, 2146 * the views will remain unaffected. If nothing is set, the default will be to use the same 2147 * transition as {@link #setExitTransition(android.transition.Transition)}. 2148 * 2149 * @return the Transition to use to move Views into the scene when reentering from a 2150 * previously-started Activity. 2151 * @attr ref android.R.styleable#Fragment_fragmentReenterTransition 2152 */ 2153 public Transition getReenterTransition() { 2154 if (mAnimationInfo == null) { 2155 return null; 2156 } 2157 return mAnimationInfo.mReenterTransition == USE_DEFAULT_TRANSITION ? getExitTransition() 2158 : mAnimationInfo.mReenterTransition; 2159 } 2160 2161 /** 2162 * Sets the Transition that will be used for shared elements transferred into the content 2163 * Scene. Typical Transitions will affect size and location, such as 2164 * {@link android.transition.ChangeBounds}. A null 2165 * value will cause transferred shared elements to blink to the final position. 2166 * 2167 * @param transition The Transition to use for shared elements transferred into the content 2168 * Scene. 2169 * @attr ref android.R.styleable#Fragment_fragmentSharedElementEnterTransition 2170 */ 2171 public void setSharedElementEnterTransition(Transition transition) { 2172 if (shouldChangeTransition(transition, null)) { 2173 ensureAnimationInfo().mSharedElementEnterTransition = transition; 2174 } 2175 } 2176 2177 /** 2178 * Returns the Transition that will be used for shared elements transferred into the content 2179 * Scene. Typical Transitions will affect size and location, such as 2180 * {@link android.transition.ChangeBounds}. A null 2181 * value will cause transferred shared elements to blink to the final position. 2182 * 2183 * @return The Transition to use for shared elements transferred into the content 2184 * Scene. 2185 * @attr ref android.R.styleable#Fragment_fragmentSharedElementEnterTransition 2186 */ 2187 public Transition getSharedElementEnterTransition() { 2188 if (mAnimationInfo == null) { 2189 return null; 2190 } 2191 return mAnimationInfo.mSharedElementEnterTransition; 2192 } 2193 2194 /** 2195 * Sets the Transition that will be used for shared elements transferred back during a 2196 * pop of the back stack. This Transition acts in the leaving Fragment. 2197 * Typical Transitions will affect size and location, such as 2198 * {@link android.transition.ChangeBounds}. A null 2199 * value will cause transferred shared elements to blink to the final position. 2200 * If no value is set, the default will be to use the same value as 2201 * {@link #setSharedElementEnterTransition(android.transition.Transition)}. 2202 * 2203 * @param transition The Transition to use for shared elements transferred out of the content 2204 * Scene. 2205 * @attr ref android.R.styleable#Fragment_fragmentSharedElementReturnTransition 2206 */ 2207 public void setSharedElementReturnTransition(Transition transition) { 2208 if (shouldChangeTransition(transition, USE_DEFAULT_TRANSITION)) { 2209 ensureAnimationInfo().mSharedElementReturnTransition = transition; 2210 } 2211 } 2212 2213 /** 2214 * Return the Transition that will be used for shared elements transferred back during a 2215 * pop of the back stack. This Transition acts in the leaving Fragment. 2216 * Typical Transitions will affect size and location, such as 2217 * {@link android.transition.ChangeBounds}. A null 2218 * value will cause transferred shared elements to blink to the final position. 2219 * If no value is set, the default will be to use the same value as 2220 * {@link #setSharedElementEnterTransition(android.transition.Transition)}. 2221 * 2222 * @return The Transition to use for shared elements transferred out of the content 2223 * Scene. 2224 * @attr ref android.R.styleable#Fragment_fragmentSharedElementReturnTransition 2225 */ 2226 public Transition getSharedElementReturnTransition() { 2227 if (mAnimationInfo == null) { 2228 return null; 2229 } 2230 return mAnimationInfo.mSharedElementReturnTransition == USE_DEFAULT_TRANSITION 2231 ? getSharedElementEnterTransition() 2232 : mAnimationInfo.mSharedElementReturnTransition; 2233 } 2234 2235 /** 2236 * Sets whether the the exit transition and enter transition overlap or not. 2237 * When true, the enter transition will start as soon as possible. When false, the 2238 * enter transition will wait until the exit transition completes before starting. 2239 * 2240 * @param allow true to start the enter transition when possible or false to 2241 * wait until the exiting transition completes. 2242 * @attr ref android.R.styleable#Fragment_fragmentAllowEnterTransitionOverlap 2243 */ 2244 public void setAllowEnterTransitionOverlap(boolean allow) { 2245 ensureAnimationInfo().mAllowEnterTransitionOverlap = allow; 2246 } 2247 2248 /** 2249 * Returns whether the the exit transition and enter transition overlap or not. 2250 * When true, the enter transition will start as soon as possible. When false, the 2251 * enter transition will wait until the exit transition completes before starting. 2252 * 2253 * @return true when the enter transition should start as soon as possible or false to 2254 * when it should wait until the exiting transition completes. 2255 * @attr ref android.R.styleable#Fragment_fragmentAllowEnterTransitionOverlap 2256 */ 2257 public boolean getAllowEnterTransitionOverlap() { 2258 return (mAnimationInfo == null || mAnimationInfo.mAllowEnterTransitionOverlap == null) 2259 ? true : mAnimationInfo.mAllowEnterTransitionOverlap; 2260 } 2261 2262 /** 2263 * Sets whether the the return transition and reenter transition overlap or not. 2264 * When true, the reenter transition will start as soon as possible. When false, the 2265 * reenter transition will wait until the return transition completes before starting. 2266 * 2267 * @param allow true to start the reenter transition when possible or false to wait until the 2268 * return transition completes. 2269 * @attr ref android.R.styleable#Fragment_fragmentAllowReturnTransitionOverlap 2270 */ 2271 public void setAllowReturnTransitionOverlap(boolean allow) { 2272 ensureAnimationInfo().mAllowReturnTransitionOverlap = allow; 2273 } 2274 2275 /** 2276 * Returns whether the the return transition and reenter transition overlap or not. 2277 * When true, the reenter transition will start as soon as possible. When false, the 2278 * reenter transition will wait until the return transition completes before starting. 2279 * 2280 * @return true to start the reenter transition when possible or false to wait until the 2281 * return transition completes. 2282 * @attr ref android.R.styleable#Fragment_fragmentAllowReturnTransitionOverlap 2283 */ 2284 public boolean getAllowReturnTransitionOverlap() { 2285 return (mAnimationInfo == null || mAnimationInfo.mAllowReturnTransitionOverlap == null) 2286 ? true : mAnimationInfo.mAllowReturnTransitionOverlap; 2287 } 2288 2289 /** 2290 * Postpone the entering Fragment transition until {@link #startPostponedEnterTransition()} 2291 * or {@link FragmentManager#executePendingTransactions()} has been called. 2292 * <p> 2293 * This method gives the Fragment the ability to delay Fragment animations 2294 * until all data is loaded. Until then, the added, shown, and 2295 * attached Fragments will be INVISIBLE and removed, hidden, and detached Fragments won't 2296 * be have their Views removed. The transaction runs when all postponed added Fragments in the 2297 * transaction have called {@link #startPostponedEnterTransition()}. 2298 * <p> 2299 * This method should be called before being added to the FragmentTransaction or 2300 * in {@link #onCreate(Bundle), {@link #onAttach(Context)}, or 2301 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}}. 2302 * {@link #startPostponedEnterTransition()} must be called to allow the Fragment to 2303 * start the transitions. 2304 * <p> 2305 * When a FragmentTransaction is started that may affect a postponed FragmentTransaction, 2306 * based on which containers are in their operations, the postponed FragmentTransaction 2307 * will have its start triggered. The early triggering may result in faulty or nonexistent 2308 * animations in the postponed transaction. FragmentTransactions that operate only on 2309 * independent containers will not interfere with each other's postponement. 2310 * <p> 2311 * Calling postponeEnterTransition on Fragments with a null View will not postpone the 2312 * transition. Likewise, postponement only works if FragmentTransaction optimizations are 2313 * enabled. 2314 * 2315 * @see Activity#postponeEnterTransition() 2316 * @see FragmentTransaction#setReorderingAllowed(boolean) 2317 */ 2318 public void postponeEnterTransition() { 2319 ensureAnimationInfo().mEnterTransitionPostponed = true; 2320 } 2321 2322 /** 2323 * Begin postponed transitions after {@link #postponeEnterTransition()} was called. 2324 * If postponeEnterTransition() was called, you must call startPostponedEnterTransition() 2325 * or {@link FragmentManager#executePendingTransactions()} to complete the FragmentTransaction. 2326 * If postponement was interrupted with {@link FragmentManager#executePendingTransactions()}, 2327 * before {@code startPostponedEnterTransition()}, animations may not run or may execute 2328 * improperly. 2329 * 2330 * @see Activity#startPostponedEnterTransition() 2331 */ 2332 public void startPostponedEnterTransition() { 2333 if (mFragmentManager == null || mFragmentManager.mHost == null) { 2334 ensureAnimationInfo().mEnterTransitionPostponed = false; 2335 } else if (Looper.myLooper() != mFragmentManager.mHost.getHandler().getLooper()) { 2336 mFragmentManager.mHost.getHandler(). 2337 postAtFrontOfQueue(this::callStartTransitionListener); 2338 } else { 2339 callStartTransitionListener(); 2340 } 2341 } 2342 2343 /** 2344 * Calls the start transition listener. This must be called on the UI thread. 2345 */ 2346 private void callStartTransitionListener() { 2347 final OnStartEnterTransitionListener listener; 2348 if (mAnimationInfo == null) { 2349 listener = null; 2350 } else { 2351 mAnimationInfo.mEnterTransitionPostponed = false; 2352 listener = mAnimationInfo.mStartEnterTransitionListener; 2353 mAnimationInfo.mStartEnterTransitionListener = null; 2354 } 2355 if (listener != null) { 2356 listener.onStartEnterTransition(); 2357 } 2358 } 2359 2360 /** 2361 * Returns true if mAnimationInfo is not null or the transition differs from the default value. 2362 * This is broken out to ensure mAnimationInfo is properly locked when checking. 2363 */ 2364 private boolean shouldChangeTransition(Transition transition, Transition defaultValue) { 2365 if (transition == defaultValue) { 2366 return mAnimationInfo != null; 2367 } 2368 return true; 2369 } 2370 2371 /** 2372 * Print the Fragments's state into the given stream. 2373 * 2374 * @param prefix Text to print at the front of each line. 2375 * @param fd The raw file descriptor that the dump is being sent to. 2376 * @param writer The PrintWriter to which you should dump your state. This will be 2377 * closed for you after you return. 2378 * @param args additional arguments to the dump request. 2379 */ 2380 public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) { 2381 writer.print(prefix); writer.print("mFragmentId=#"); 2382 writer.print(Integer.toHexString(mFragmentId)); 2383 writer.print(" mContainerId=#"); 2384 writer.print(Integer.toHexString(mContainerId)); 2385 writer.print(" mTag="); writer.println(mTag); 2386 writer.print(prefix); writer.print("mState="); writer.print(mState); 2387 writer.print(" mIndex="); writer.print(mIndex); 2388 writer.print(" mWho="); writer.print(mWho); 2389 writer.print(" mBackStackNesting="); writer.println(mBackStackNesting); 2390 writer.print(prefix); writer.print("mAdded="); writer.print(mAdded); 2391 writer.print(" mRemoving="); writer.print(mRemoving); 2392 writer.print(" mFromLayout="); writer.print(mFromLayout); 2393 writer.print(" mInLayout="); writer.println(mInLayout); 2394 writer.print(prefix); writer.print("mHidden="); writer.print(mHidden); 2395 writer.print(" mDetached="); writer.print(mDetached); 2396 writer.print(" mMenuVisible="); writer.print(mMenuVisible); 2397 writer.print(" mHasMenu="); writer.println(mHasMenu); 2398 writer.print(prefix); writer.print("mRetainInstance="); writer.print(mRetainInstance); 2399 writer.print(" mRetaining="); writer.print(mRetaining); 2400 writer.print(" mUserVisibleHint="); writer.println(mUserVisibleHint); 2401 if (mFragmentManager != null) { 2402 writer.print(prefix); writer.print("mFragmentManager="); 2403 writer.println(mFragmentManager); 2404 } 2405 if (mHost != null) { 2406 writer.print(prefix); writer.print("mHost="); 2407 writer.println(mHost); 2408 } 2409 if (mParentFragment != null) { 2410 writer.print(prefix); writer.print("mParentFragment="); 2411 writer.println(mParentFragment); 2412 } 2413 if (mArguments != null) { 2414 writer.print(prefix); writer.print("mArguments="); writer.println(mArguments); 2415 } 2416 if (mSavedFragmentState != null) { 2417 writer.print(prefix); writer.print("mSavedFragmentState="); 2418 writer.println(mSavedFragmentState); 2419 } 2420 if (mSavedViewState != null) { 2421 writer.print(prefix); writer.print("mSavedViewState="); 2422 writer.println(mSavedViewState); 2423 } 2424 if (mTarget != null) { 2425 writer.print(prefix); writer.print("mTarget="); writer.print(mTarget); 2426 writer.print(" mTargetRequestCode="); 2427 writer.println(mTargetRequestCode); 2428 } 2429 if (getNextAnim() != 0) { 2430 writer.print(prefix); writer.print("mNextAnim="); writer.println(getNextAnim()); 2431 } 2432 if (mContainer != null) { 2433 writer.print(prefix); writer.print("mContainer="); writer.println(mContainer); 2434 } 2435 if (mView != null) { 2436 writer.print(prefix); writer.print("mView="); writer.println(mView); 2437 } 2438 if (getAnimatingAway() != null) { 2439 writer.print(prefix); writer.print("mAnimatingAway="); 2440 writer.println(getAnimatingAway()); 2441 writer.print(prefix); writer.print("mStateAfterAnimating="); 2442 writer.println(getStateAfterAnimating()); 2443 } 2444 if (mLoaderManager != null) { 2445 writer.print(prefix); writer.println("Loader Manager:"); 2446 mLoaderManager.dump(prefix + " ", fd, writer, args); 2447 } 2448 if (mChildFragmentManager != null) { 2449 writer.print(prefix); writer.println("Child " + mChildFragmentManager + ":"); 2450 mChildFragmentManager.dump(prefix + " ", fd, writer, args); 2451 } 2452 } 2453 2454 Fragment findFragmentByWho(String who) { 2455 if (who.equals(mWho)) { 2456 return this; 2457 } 2458 if (mChildFragmentManager != null) { 2459 return mChildFragmentManager.findFragmentByWho(who); 2460 } 2461 return null; 2462 } 2463 2464 void instantiateChildFragmentManager() { 2465 mChildFragmentManager = new FragmentManagerImpl(); 2466 mChildFragmentManager.attachController(mHost, new FragmentContainer() { 2467 @Override 2468 @Nullable 2469 public <T extends View> T onFindViewById(int id) { 2470 if (mView == null) { 2471 throw new IllegalStateException("Fragment does not have a view"); 2472 } 2473 return mView.findViewById(id); 2474 } 2475 2476 @Override 2477 public boolean onHasView() { 2478 return (mView != null); 2479 } 2480 }, this); 2481 } 2482 2483 void performCreate(Bundle savedInstanceState) { 2484 if (mChildFragmentManager != null) { 2485 mChildFragmentManager.noteStateNotSaved(); 2486 } 2487 mState = CREATED; 2488 mCalled = false; 2489 onCreate(savedInstanceState); 2490 mIsCreated = true; 2491 if (!mCalled) { 2492 throw new SuperNotCalledException("Fragment " + this 2493 + " did not call through to super.onCreate()"); 2494 } 2495 final Context context = getContext(); 2496 final int version = context != null ? context.getApplicationInfo().targetSdkVersion : 0; 2497 if (version < Build.VERSION_CODES.N) { 2498 restoreChildFragmentState(savedInstanceState, false); 2499 } 2500 } 2501 2502 View performCreateView(LayoutInflater inflater, ViewGroup container, 2503 Bundle savedInstanceState) { 2504 if (mChildFragmentManager != null) { 2505 mChildFragmentManager.noteStateNotSaved(); 2506 } 2507 mPerformedCreateView = true; 2508 return onCreateView(inflater, container, savedInstanceState); 2509 } 2510 2511 void performActivityCreated(Bundle savedInstanceState) { 2512 if (mChildFragmentManager != null) { 2513 mChildFragmentManager.noteStateNotSaved(); 2514 } 2515 mState = ACTIVITY_CREATED; 2516 mCalled = false; 2517 onActivityCreated(savedInstanceState); 2518 if (!mCalled) { 2519 throw new SuperNotCalledException("Fragment " + this 2520 + " did not call through to super.onActivityCreated()"); 2521 } 2522 if (mChildFragmentManager != null) { 2523 mChildFragmentManager.dispatchActivityCreated(); 2524 } 2525 } 2526 2527 void performStart() { 2528 if (mChildFragmentManager != null) { 2529 mChildFragmentManager.noteStateNotSaved(); 2530 mChildFragmentManager.execPendingActions(); 2531 } 2532 mState = STARTED; 2533 mCalled = false; 2534 onStart(); 2535 if (!mCalled) { 2536 throw new SuperNotCalledException("Fragment " + this 2537 + " did not call through to super.onStart()"); 2538 } 2539 if (mChildFragmentManager != null) { 2540 mChildFragmentManager.dispatchStart(); 2541 } 2542 if (mLoaderManager != null) { 2543 mLoaderManager.doReportStart(); 2544 } 2545 } 2546 2547 void performResume() { 2548 if (mChildFragmentManager != null) { 2549 mChildFragmentManager.noteStateNotSaved(); 2550 mChildFragmentManager.execPendingActions(); 2551 } 2552 mState = RESUMED; 2553 mCalled = false; 2554 onResume(); 2555 if (!mCalled) { 2556 throw new SuperNotCalledException("Fragment " + this 2557 + " did not call through to super.onResume()"); 2558 } 2559 if (mChildFragmentManager != null) { 2560 mChildFragmentManager.dispatchResume(); 2561 mChildFragmentManager.execPendingActions(); 2562 } 2563 } 2564 2565 void noteStateNotSaved() { 2566 if (mChildFragmentManager != null) { 2567 mChildFragmentManager.noteStateNotSaved(); 2568 } 2569 } 2570 2571 @Deprecated 2572 void performMultiWindowModeChanged(boolean isInMultiWindowMode) { 2573 onMultiWindowModeChanged(isInMultiWindowMode); 2574 if (mChildFragmentManager != null) { 2575 mChildFragmentManager.dispatchMultiWindowModeChanged(isInMultiWindowMode); 2576 } 2577 } 2578 2579 void performMultiWindowModeChanged(boolean isInMultiWindowMode, Configuration newConfig) { 2580 onMultiWindowModeChanged(isInMultiWindowMode, newConfig); 2581 if (mChildFragmentManager != null) { 2582 mChildFragmentManager.dispatchMultiWindowModeChanged(isInMultiWindowMode, newConfig); 2583 } 2584 } 2585 2586 @Deprecated 2587 void performPictureInPictureModeChanged(boolean isInPictureInPictureMode) { 2588 onPictureInPictureModeChanged(isInPictureInPictureMode); 2589 if (mChildFragmentManager != null) { 2590 mChildFragmentManager.dispatchPictureInPictureModeChanged(isInPictureInPictureMode); 2591 } 2592 } 2593 2594 void performPictureInPictureModeChanged(boolean isInPictureInPictureMode, 2595 Configuration newConfig) { 2596 onPictureInPictureModeChanged(isInPictureInPictureMode, newConfig); 2597 if (mChildFragmentManager != null) { 2598 mChildFragmentManager.dispatchPictureInPictureModeChanged(isInPictureInPictureMode, 2599 newConfig); 2600 } 2601 } 2602 2603 void performConfigurationChanged(Configuration newConfig) { 2604 onConfigurationChanged(newConfig); 2605 if (mChildFragmentManager != null) { 2606 mChildFragmentManager.dispatchConfigurationChanged(newConfig); 2607 } 2608 } 2609 2610 void performLowMemory() { 2611 onLowMemory(); 2612 if (mChildFragmentManager != null) { 2613 mChildFragmentManager.dispatchLowMemory(); 2614 } 2615 } 2616 2617 void performTrimMemory(int level) { 2618 onTrimMemory(level); 2619 if (mChildFragmentManager != null) { 2620 mChildFragmentManager.dispatchTrimMemory(level); 2621 } 2622 } 2623 2624 boolean performCreateOptionsMenu(Menu menu, MenuInflater inflater) { 2625 boolean show = false; 2626 if (!mHidden) { 2627 if (mHasMenu && mMenuVisible) { 2628 show = true; 2629 onCreateOptionsMenu(menu, inflater); 2630 } 2631 if (mChildFragmentManager != null) { 2632 show |= mChildFragmentManager.dispatchCreateOptionsMenu(menu, inflater); 2633 } 2634 } 2635 return show; 2636 } 2637 2638 boolean performPrepareOptionsMenu(Menu menu) { 2639 boolean show = false; 2640 if (!mHidden) { 2641 if (mHasMenu && mMenuVisible) { 2642 show = true; 2643 onPrepareOptionsMenu(menu); 2644 } 2645 if (mChildFragmentManager != null) { 2646 show |= mChildFragmentManager.dispatchPrepareOptionsMenu(menu); 2647 } 2648 } 2649 return show; 2650 } 2651 2652 boolean performOptionsItemSelected(MenuItem item) { 2653 if (!mHidden) { 2654 if (mHasMenu && mMenuVisible) { 2655 if (onOptionsItemSelected(item)) { 2656 return true; 2657 } 2658 } 2659 if (mChildFragmentManager != null) { 2660 if (mChildFragmentManager.dispatchOptionsItemSelected(item)) { 2661 return true; 2662 } 2663 } 2664 } 2665 return false; 2666 } 2667 2668 boolean performContextItemSelected(MenuItem item) { 2669 if (!mHidden) { 2670 if (onContextItemSelected(item)) { 2671 return true; 2672 } 2673 if (mChildFragmentManager != null) { 2674 if (mChildFragmentManager.dispatchContextItemSelected(item)) { 2675 return true; 2676 } 2677 } 2678 } 2679 return false; 2680 } 2681 2682 void performOptionsMenuClosed(Menu menu) { 2683 if (!mHidden) { 2684 if (mHasMenu && mMenuVisible) { 2685 onOptionsMenuClosed(menu); 2686 } 2687 if (mChildFragmentManager != null) { 2688 mChildFragmentManager.dispatchOptionsMenuClosed(menu); 2689 } 2690 } 2691 } 2692 2693 void performSaveInstanceState(Bundle outState) { 2694 onSaveInstanceState(outState); 2695 if (mChildFragmentManager != null) { 2696 Parcelable p = mChildFragmentManager.saveAllState(); 2697 if (p != null) { 2698 outState.putParcelable(Activity.FRAGMENTS_TAG, p); 2699 } 2700 } 2701 } 2702 2703 void performPause() { 2704 if (mChildFragmentManager != null) { 2705 mChildFragmentManager.dispatchPause(); 2706 } 2707 mState = STARTED; 2708 mCalled = false; 2709 onPause(); 2710 if (!mCalled) { 2711 throw new SuperNotCalledException("Fragment " + this 2712 + " did not call through to super.onPause()"); 2713 } 2714 } 2715 2716 void performStop() { 2717 if (mChildFragmentManager != null) { 2718 mChildFragmentManager.dispatchStop(); 2719 } 2720 mState = STOPPED; 2721 mCalled = false; 2722 onStop(); 2723 if (!mCalled) { 2724 throw new SuperNotCalledException("Fragment " + this 2725 + " did not call through to super.onStop()"); 2726 } 2727 2728 if (mLoadersStarted) { 2729 mLoadersStarted = false; 2730 if (!mCheckedForLoaderManager) { 2731 mCheckedForLoaderManager = true; 2732 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 2733 } 2734 if (mLoaderManager != null) { 2735 if (mHost.getRetainLoaders()) { 2736 mLoaderManager.doRetain(); 2737 } else { 2738 mLoaderManager.doStop(); 2739 } 2740 } 2741 } 2742 } 2743 2744 void performDestroyView() { 2745 if (mChildFragmentManager != null) { 2746 mChildFragmentManager.dispatchDestroyView(); 2747 } 2748 mState = CREATED; 2749 mCalled = false; 2750 onDestroyView(); 2751 if (!mCalled) { 2752 throw new SuperNotCalledException("Fragment " + this 2753 + " did not call through to super.onDestroyView()"); 2754 } 2755 if (mLoaderManager != null) { 2756 mLoaderManager.doReportNextStart(); 2757 } 2758 mPerformedCreateView = false; 2759 } 2760 2761 void performDestroy() { 2762 if (mChildFragmentManager != null) { 2763 mChildFragmentManager.dispatchDestroy(); 2764 } 2765 mState = INITIALIZING; 2766 mCalled = false; 2767 mIsCreated = false; 2768 onDestroy(); 2769 if (!mCalled) { 2770 throw new SuperNotCalledException("Fragment " + this 2771 + " did not call through to super.onDestroy()"); 2772 } 2773 mChildFragmentManager = null; 2774 } 2775 2776 void performDetach() { 2777 mCalled = false; 2778 onDetach(); 2779 mLayoutInflater = null; 2780 if (!mCalled) { 2781 throw new SuperNotCalledException("Fragment " + this 2782 + " did not call through to super.onDetach()"); 2783 } 2784 2785 // Destroy the child FragmentManager if we still have it here. 2786 // We won't unless we're retaining our instance and if we do, 2787 // our child FragmentManager instance state will have already been saved. 2788 if (mChildFragmentManager != null) { 2789 if (!mRetaining) { 2790 throw new IllegalStateException("Child FragmentManager of " + this + " was not " 2791 + " destroyed and this fragment is not retaining instance"); 2792 } 2793 mChildFragmentManager.dispatchDestroy(); 2794 mChildFragmentManager = null; 2795 } 2796 } 2797 2798 void setOnStartEnterTransitionListener(OnStartEnterTransitionListener listener) { 2799 ensureAnimationInfo(); 2800 if (listener == mAnimationInfo.mStartEnterTransitionListener) { 2801 return; 2802 } 2803 if (listener != null && mAnimationInfo.mStartEnterTransitionListener != null) { 2804 throw new IllegalStateException("Trying to set a replacement " + 2805 "startPostponedEnterTransition on " + this); 2806 } 2807 if (mAnimationInfo.mEnterTransitionPostponed) { 2808 mAnimationInfo.mStartEnterTransitionListener = listener; 2809 } 2810 if (listener != null) { 2811 listener.startListening(); 2812 } 2813 } 2814 2815 private static Transition loadTransition(Context context, TypedArray typedArray, 2816 Transition currentValue, Transition defaultValue, int id) { 2817 if (currentValue != defaultValue) { 2818 return currentValue; 2819 } 2820 int transitionId = typedArray.getResourceId(id, 0); 2821 Transition transition = defaultValue; 2822 if (transitionId != 0 && transitionId != com.android.internal.R.transition.no_transition) { 2823 TransitionInflater inflater = TransitionInflater.from(context); 2824 transition = inflater.inflateTransition(transitionId); 2825 if (transition instanceof TransitionSet && 2826 ((TransitionSet)transition).getTransitionCount() == 0) { 2827 transition = null; 2828 } 2829 } 2830 return transition; 2831 } 2832 2833 private AnimationInfo ensureAnimationInfo() { 2834 if (mAnimationInfo == null) { 2835 mAnimationInfo = new AnimationInfo(); 2836 } 2837 return mAnimationInfo; 2838 } 2839 2840 int getNextAnim() { 2841 if (mAnimationInfo == null) { 2842 return 0; 2843 } 2844 return mAnimationInfo.mNextAnim; 2845 } 2846 2847 void setNextAnim(int animResourceId) { 2848 if (mAnimationInfo == null && animResourceId == 0) { 2849 return; // no change! 2850 } 2851 ensureAnimationInfo().mNextAnim = animResourceId; 2852 } 2853 2854 int getNextTransition() { 2855 if (mAnimationInfo == null) { 2856 return 0; 2857 } 2858 return mAnimationInfo.mNextTransition; 2859 } 2860 2861 void setNextTransition(int nextTransition, int nextTransitionStyle) { 2862 if (mAnimationInfo == null && nextTransition == 0 && nextTransitionStyle == 0) { 2863 return; // no change! 2864 } 2865 ensureAnimationInfo(); 2866 mAnimationInfo.mNextTransition = nextTransition; 2867 mAnimationInfo.mNextTransitionStyle = nextTransitionStyle; 2868 } 2869 2870 int getNextTransitionStyle() { 2871 if (mAnimationInfo == null) { 2872 return 0; 2873 } 2874 return mAnimationInfo.mNextTransitionStyle; 2875 } 2876 2877 SharedElementCallback getEnterTransitionCallback() { 2878 if (mAnimationInfo == null) { 2879 return SharedElementCallback.NULL_CALLBACK; 2880 } 2881 return mAnimationInfo.mEnterTransitionCallback; 2882 } 2883 2884 SharedElementCallback getExitTransitionCallback() { 2885 if (mAnimationInfo == null) { 2886 return SharedElementCallback.NULL_CALLBACK; 2887 } 2888 return mAnimationInfo.mExitTransitionCallback; 2889 } 2890 2891 Animator getAnimatingAway() { 2892 if (mAnimationInfo == null) { 2893 return null; 2894 } 2895 return mAnimationInfo.mAnimatingAway; 2896 } 2897 2898 void setAnimatingAway(Animator animator) { 2899 ensureAnimationInfo().mAnimatingAway = animator; 2900 } 2901 2902 int getStateAfterAnimating() { 2903 if (mAnimationInfo == null) { 2904 return 0; 2905 } 2906 return mAnimationInfo.mStateAfterAnimating; 2907 } 2908 2909 void setStateAfterAnimating(int state) { 2910 ensureAnimationInfo().mStateAfterAnimating = state; 2911 } 2912 2913 boolean isPostponed() { 2914 if (mAnimationInfo == null) { 2915 return false; 2916 } 2917 return mAnimationInfo.mEnterTransitionPostponed; 2918 } 2919 2920 boolean isHideReplaced() { 2921 if (mAnimationInfo == null) { 2922 return false; 2923 } 2924 return mAnimationInfo.mIsHideReplaced; 2925 } 2926 2927 void setHideReplaced(boolean replaced) { 2928 ensureAnimationInfo().mIsHideReplaced = replaced; 2929 } 2930 2931 /** 2932 * Used internally to be notified when {@link #startPostponedEnterTransition()} has 2933 * been called. This listener will only be called once and then be removed from the 2934 * listeners. 2935 */ 2936 interface OnStartEnterTransitionListener { 2937 void onStartEnterTransition(); 2938 void startListening(); 2939 } 2940 2941 /** 2942 * Contains all the animation and transition information for a fragment. This will only 2943 * be instantiated for Fragments that have Views. 2944 */ 2945 static class AnimationInfo { 2946 // Non-null if the fragment's view hierarchy is currently animating away, 2947 // meaning we need to wait a bit on completely destroying it. This is the 2948 // animation that is running. 2949 Animator mAnimatingAway; 2950 2951 // If mAnimatingAway != null, this is the state we should move to once the 2952 // animation is done. 2953 int mStateAfterAnimating; 2954 2955 // If app has requested a specific animation, this is the one to use. 2956 int mNextAnim; 2957 2958 // If app has requested a specific transition, this is the one to use. 2959 int mNextTransition; 2960 2961 // If app has requested a specific transition style, this is the one to use. 2962 int mNextTransitionStyle; 2963 2964 private Transition mEnterTransition = null; 2965 private Transition mReturnTransition = USE_DEFAULT_TRANSITION; 2966 private Transition mExitTransition = null; 2967 private Transition mReenterTransition = USE_DEFAULT_TRANSITION; 2968 private Transition mSharedElementEnterTransition = null; 2969 private Transition mSharedElementReturnTransition = USE_DEFAULT_TRANSITION; 2970 private Boolean mAllowReturnTransitionOverlap; 2971 private Boolean mAllowEnterTransitionOverlap; 2972 2973 SharedElementCallback mEnterTransitionCallback = SharedElementCallback.NULL_CALLBACK; 2974 SharedElementCallback mExitTransitionCallback = SharedElementCallback.NULL_CALLBACK; 2975 2976 // True when postponeEnterTransition has been called and startPostponeEnterTransition 2977 // hasn't been called yet. 2978 boolean mEnterTransitionPostponed; 2979 2980 // Listener to wait for startPostponeEnterTransition. After being called, it will 2981 // be set to null 2982 OnStartEnterTransitionListener mStartEnterTransitionListener; 2983 2984 // True if the View was hidden, but the transition is handling the hide 2985 boolean mIsHideReplaced; 2986 } 2987} 2988