Fragment.java revision 9e136b88ba6a51ebb7c639dd186cc33b79a1b3d0
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.NonNull; 21import android.annotation.Nullable; 22import android.annotation.StringRes; 23import android.content.ComponentCallbacks2; 24import android.content.Context; 25import android.content.Intent; 26import android.content.res.Configuration; 27import android.content.res.Resources; 28import android.content.res.TypedArray; 29import android.os.Bundle; 30import android.os.Parcel; 31import android.os.Parcelable; 32import android.transition.Transition; 33import android.transition.TransitionInflater; 34import android.transition.TransitionSet; 35import android.util.AndroidRuntimeException; 36import android.util.ArrayMap; 37import android.util.AttributeSet; 38import android.util.DebugUtils; 39import android.util.Log; 40import android.util.SparseArray; 41import android.util.SuperNotCalledException; 42import android.view.ContextMenu; 43import android.view.ContextMenu.ContextMenuInfo; 44import android.view.LayoutInflater; 45import android.view.Menu; 46import android.view.MenuInflater; 47import android.view.MenuItem; 48import android.view.View; 49import android.view.View.OnCreateContextMenuListener; 50import android.view.ViewGroup; 51import android.widget.AdapterView; 52 53import java.io.FileDescriptor; 54import java.io.PrintWriter; 55 56final class FragmentState implements Parcelable { 57 final String mClassName; 58 final int mIndex; 59 final boolean mFromLayout; 60 final int mFragmentId; 61 final int mContainerId; 62 final String mTag; 63 final boolean mRetainInstance; 64 final boolean mDetached; 65 final Bundle mArguments; 66 67 Bundle mSavedFragmentState; 68 69 Fragment mInstance; 70 71 public FragmentState(Fragment frag) { 72 mClassName = frag.getClass().getName(); 73 mIndex = frag.mIndex; 74 mFromLayout = frag.mFromLayout; 75 mFragmentId = frag.mFragmentId; 76 mContainerId = frag.mContainerId; 77 mTag = frag.mTag; 78 mRetainInstance = frag.mRetainInstance; 79 mDetached = frag.mDetached; 80 mArguments = frag.mArguments; 81 } 82 83 public FragmentState(Parcel in) { 84 mClassName = in.readString(); 85 mIndex = in.readInt(); 86 mFromLayout = in.readInt() != 0; 87 mFragmentId = in.readInt(); 88 mContainerId = in.readInt(); 89 mTag = in.readString(); 90 mRetainInstance = in.readInt() != 0; 91 mDetached = in.readInt() != 0; 92 mArguments = in.readBundle(); 93 mSavedFragmentState = in.readBundle(); 94 } 95 96 public Fragment instantiate(FragmentHostCallback host, Fragment parent) { 97 if (mInstance != null) { 98 return mInstance; 99 } 100 101 final Context context = host.getContext(); 102 if (mArguments != null) { 103 mArguments.setClassLoader(context.getClassLoader()); 104 } 105 106 mInstance = Fragment.instantiate(context, mClassName, mArguments); 107 108 if (mSavedFragmentState != null) { 109 mSavedFragmentState.setClassLoader(context.getClassLoader()); 110 mInstance.mSavedFragmentState = mSavedFragmentState; 111 } 112 mInstance.setIndex(mIndex, parent); 113 mInstance.mFromLayout = mFromLayout; 114 mInstance.mRestored = true; 115 mInstance.mFragmentId = mFragmentId; 116 mInstance.mContainerId = mContainerId; 117 mInstance.mTag = mTag; 118 mInstance.mRetainInstance = mRetainInstance; 119 mInstance.mDetached = mDetached; 120 mInstance.mFragmentManager = host.mFragmentManager; 121 if (FragmentManagerImpl.DEBUG) Log.v(FragmentManagerImpl.TAG, 122 "Instantiated fragment " + mInstance); 123 124 return mInstance; 125 } 126 127 public int describeContents() { 128 return 0; 129 } 130 131 public void writeToParcel(Parcel dest, int flags) { 132 dest.writeString(mClassName); 133 dest.writeInt(mIndex); 134 dest.writeInt(mFromLayout ? 1 : 0); 135 dest.writeInt(mFragmentId); 136 dest.writeInt(mContainerId); 137 dest.writeString(mTag); 138 dest.writeInt(mRetainInstance ? 1 : 0); 139 dest.writeInt(mDetached ? 1 : 0); 140 dest.writeBundle(mArguments); 141 dest.writeBundle(mSavedFragmentState); 142 } 143 144 public static final Parcelable.Creator<FragmentState> CREATOR 145 = new Parcelable.Creator<FragmentState>() { 146 public FragmentState createFromParcel(Parcel in) { 147 return new FragmentState(in); 148 } 149 150 public FragmentState[] newArray(int size) { 151 return new FragmentState[size]; 152 } 153 }; 154} 155 156/** 157 * A Fragment is a piece of an application's user interface or behavior 158 * that can be placed in an {@link Activity}. Interaction with fragments 159 * is done through {@link FragmentManager}, which can be obtained via 160 * {@link Activity#getFragmentManager() Activity.getFragmentManager()} and 161 * {@link Fragment#getFragmentManager() Fragment.getFragmentManager()}. 162 * 163 * <p>The Fragment class can be used many ways to achieve a wide variety of 164 * results. In its core, it represents a particular operation or interface 165 * that is running within a larger {@link Activity}. A Fragment is closely 166 * tied to the Activity it is in, and can not be used apart from one. Though 167 * Fragment defines its own lifecycle, that lifecycle is dependent on its 168 * activity: if the activity is stopped, no fragments inside of it can be 169 * started; when the activity is destroyed, all fragments will be destroyed. 170 * 171 * <p>All subclasses of Fragment must include a public no-argument constructor. 172 * The framework will often re-instantiate a fragment class when needed, 173 * in particular during state restore, and needs to be able to find this 174 * constructor to instantiate it. If the no-argument constructor is not 175 * available, a runtime exception will occur in some cases during state 176 * restore. 177 * 178 * <p>Topics covered here: 179 * <ol> 180 * <li><a href="#OlderPlatforms">Older Platforms</a> 181 * <li><a href="#Lifecycle">Lifecycle</a> 182 * <li><a href="#Layout">Layout</a> 183 * <li><a href="#BackStack">Back Stack</a> 184 * </ol> 185 * 186 * <div class="special reference"> 187 * <h3>Developer Guides</h3> 188 * <p>For more information about using fragments, read the 189 * <a href="{@docRoot}guide/topics/fundamentals/fragments.html">Fragments</a> developer guide.</p> 190 * </div> 191 * 192 * <a name="OlderPlatforms"></a> 193 * <h3>Older Platforms</h3> 194 * 195 * While the Fragment API was introduced in 196 * {@link android.os.Build.VERSION_CODES#HONEYCOMB}, a version of the API 197 * at is also available for use on older platforms through 198 * {@link android.support.v4.app.FragmentActivity}. See the blog post 199 * <a href="http://android-developers.blogspot.com/2011/03/fragments-for-all.html"> 200 * Fragments For All</a> for more details. 201 * 202 * <a name="Lifecycle"></a> 203 * <h3>Lifecycle</h3> 204 * 205 * <p>Though a Fragment's lifecycle is tied to its owning activity, it has 206 * its own wrinkle on the standard activity lifecycle. It includes basic 207 * activity lifecycle methods such as {@link #onResume}, but also important 208 * are methods related to interactions with the activity and UI generation. 209 * 210 * <p>The core series of lifecycle methods that are called to bring a fragment 211 * up to resumed state (interacting with the user) are: 212 * 213 * <ol> 214 * <li> {@link #onAttach} called once the fragment is associated with its activity. 215 * <li> {@link #onCreate} called to do initial creation of the fragment. 216 * <li> {@link #onCreateView} creates and returns the view hierarchy associated 217 * with the fragment. 218 * <li> {@link #onActivityCreated} tells the fragment that its activity has 219 * completed its own {@link Activity#onCreate Activity.onCreate()}. 220 * <li> {@link #onViewStateRestored} tells the fragment that all of the saved 221 * state of its view hierarchy has been restored. 222 * <li> {@link #onStart} makes the fragment visible to the user (based on its 223 * containing activity being started). 224 * <li> {@link #onResume} makes the fragment begin interacting with the user 225 * (based on its containing activity being resumed). 226 * </ol> 227 * 228 * <p>As a fragment is no longer being used, it goes through a reverse 229 * series of callbacks: 230 * 231 * <ol> 232 * <li> {@link #onPause} fragment is no longer interacting with the user either 233 * because its activity is being paused or a fragment operation is modifying it 234 * in the activity. 235 * <li> {@link #onStop} fragment is no longer visible to the user either 236 * because its activity is being stopped or a fragment operation is modifying it 237 * in the activity. 238 * <li> {@link #onDestroyView} allows the fragment to clean up resources 239 * associated with its View. 240 * <li> {@link #onDestroy} called to do final cleanup of the fragment's state. 241 * <li> {@link #onDetach} called immediately prior to the fragment no longer 242 * being associated with its activity. 243 * </ol> 244 * 245 * <a name="Layout"></a> 246 * <h3>Layout</h3> 247 * 248 * <p>Fragments can be used as part of your application's layout, allowing 249 * you to better modularize your code and more easily adjust your user 250 * interface to the screen it is running on. As an example, we can look 251 * at a simple program consisting of a list of items, and display of the 252 * details of each item.</p> 253 * 254 * <p>An activity's layout XML can include <code><fragment></code> tags 255 * to embed fragment instances inside of the layout. For example, here is 256 * a simple layout that embeds one fragment:</p> 257 * 258 * {@sample development/samples/ApiDemos/res/layout/fragment_layout.xml layout} 259 * 260 * <p>The layout is installed in the activity in the normal way:</p> 261 * 262 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 263 * main} 264 * 265 * <p>The titles fragment, showing a list of titles, is fairly simple, relying 266 * on {@link ListFragment} for most of its work. Note the implementation of 267 * clicking an item: depending on the current activity's layout, it can either 268 * create and display a new fragment to show the details in-place (more about 269 * this later), or start a new activity to show the details.</p> 270 * 271 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 272 * titles} 273 * 274 * <p>The details fragment showing the contents of a selected item just 275 * displays a string of text based on an index of a string array built in to 276 * the app:</p> 277 * 278 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 279 * details} 280 * 281 * <p>In this case when the user clicks on a title, there is no details 282 * container in the current activity, so the titles fragment's click code will 283 * launch a new activity to display the details fragment:</p> 284 * 285 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 286 * details_activity} 287 * 288 * <p>However the screen may be large enough to show both the list of titles 289 * and details about the currently selected title. To use such a layout on 290 * a landscape screen, this alternative layout can be placed under layout-land:</p> 291 * 292 * {@sample development/samples/ApiDemos/res/layout-land/fragment_layout.xml layout} 293 * 294 * <p>Note how the prior code will adjust to this alternative UI flow: the titles 295 * fragment will now embed the details fragment inside of this activity, and the 296 * details activity will finish itself if it is running in a configuration 297 * where the details can be shown in-place. 298 * 299 * <p>When a configuration change causes the activity hosting these fragments 300 * to restart, its new instance may use a different layout that doesn't 301 * include the same fragments as the previous layout. In this case all of 302 * the previous fragments will still be instantiated and running in the new 303 * instance. However, any that are no longer associated with a <fragment> 304 * tag in the view hierarchy will not have their content view created 305 * and will return false from {@link #isInLayout}. (The code here also shows 306 * how you can determine if a fragment placed in a container is no longer 307 * running in a layout with that container and avoid creating its view hierarchy 308 * in that case.) 309 * 310 * <p>The attributes of the <fragment> tag are used to control the 311 * LayoutParams provided when attaching the fragment's view to the parent 312 * container. They can also be parsed by the fragment in {@link #onInflate} 313 * as parameters. 314 * 315 * <p>The fragment being instantiated must have some kind of unique identifier 316 * so that it can be re-associated with a previous instance if the parent 317 * activity needs to be destroyed and recreated. This can be provided these 318 * ways: 319 * 320 * <ul> 321 * <li>If nothing is explicitly supplied, the view ID of the container will 322 * be used. 323 * <li><code>android:tag</code> can be used in <fragment> to provide 324 * a specific tag name for the fragment. 325 * <li><code>android:id</code> can be used in <fragment> to provide 326 * a specific identifier for the fragment. 327 * </ul> 328 * 329 * <a name="BackStack"></a> 330 * <h3>Back Stack</h3> 331 * 332 * <p>The transaction in which fragments are modified can be placed on an 333 * internal back-stack of the owning activity. When the user presses back 334 * in the activity, any transactions on the back stack are popped off before 335 * the activity itself is finished. 336 * 337 * <p>For example, consider this simple fragment that is instantiated with 338 * an integer argument and displays that in a TextView in its UI:</p> 339 * 340 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 341 * fragment} 342 * 343 * <p>A function that creates a new instance of the fragment, replacing 344 * whatever current fragment instance is being shown and pushing that change 345 * on to the back stack could be written as: 346 * 347 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 348 * add_stack} 349 * 350 * <p>After each call to this function, a new entry is on the stack, and 351 * pressing back will pop it to return the user to whatever previous state 352 * the activity UI was in. 353 */ 354public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListener { 355 private static final ArrayMap<String, Class<?>> sClassMap = 356 new ArrayMap<String, Class<?>>(); 357 358 static final int INVALID_STATE = -1; // Invalid state used as a null value. 359 static final int INITIALIZING = 0; // Not yet created. 360 static final int CREATED = 1; // Created. 361 static final int ACTIVITY_CREATED = 2; // The activity has finished its creation. 362 static final int STOPPED = 3; // Fully created, not started. 363 static final int STARTED = 4; // Created and started, not resumed. 364 static final int RESUMED = 5; // Created started and resumed. 365 366 private static final Transition USE_DEFAULT_TRANSITION = new TransitionSet(); 367 368 int mState = INITIALIZING; 369 370 // Non-null if the fragment's view hierarchy is currently animating away, 371 // meaning we need to wait a bit on completely destroying it. This is the 372 // animation that is running. 373 Animator mAnimatingAway; 374 375 // If mAnimatingAway != null, this is the state we should move to once the 376 // animation is done. 377 int mStateAfterAnimating; 378 379 // When instantiated from saved state, this is the saved state. 380 Bundle mSavedFragmentState; 381 SparseArray<Parcelable> mSavedViewState; 382 383 // Index into active fragment array. 384 int mIndex = -1; 385 386 // Internal unique name for this fragment; 387 String mWho; 388 389 // Construction arguments; 390 Bundle mArguments; 391 392 // Target fragment. 393 Fragment mTarget; 394 395 // For use when retaining a fragment: this is the index of the last mTarget. 396 int mTargetIndex = -1; 397 398 // Target request code. 399 int mTargetRequestCode; 400 401 // True if the fragment is in the list of added fragments. 402 boolean mAdded; 403 404 // If set this fragment is being removed from its activity. 405 boolean mRemoving; 406 407 // True if the fragment is in the resumed state. 408 boolean mResumed; 409 410 // Set to true if this fragment was instantiated from a layout file. 411 boolean mFromLayout; 412 413 // Set to true when the view has actually been inflated in its layout. 414 boolean mInLayout; 415 416 // True if this fragment has been restored from previously saved state. 417 boolean mRestored; 418 419 // Number of active back stack entries this fragment is in. 420 int mBackStackNesting; 421 422 // The fragment manager we are associated with. Set as soon as the 423 // fragment is used in a transaction; cleared after it has been removed 424 // from all transactions. 425 FragmentManagerImpl mFragmentManager; 426 427 // Activity this fragment is attached to. 428 FragmentHostCallback mHost; 429 430 // Private fragment manager for child fragments inside of this one. 431 FragmentManagerImpl mChildFragmentManager; 432 433 // If this Fragment is contained in another Fragment, this is that container. 434 Fragment mParentFragment; 435 436 // The optional identifier for this fragment -- either the container ID if it 437 // was dynamically added to the view hierarchy, or the ID supplied in 438 // layout. 439 int mFragmentId; 440 441 // When a fragment is being dynamically added to the view hierarchy, this 442 // is the identifier of the parent container it is being added to. 443 int mContainerId; 444 445 // The optional named tag for this fragment -- usually used to find 446 // fragments that are not part of the layout. 447 String mTag; 448 449 // Set to true when the app has requested that this fragment be hidden 450 // from the user. 451 boolean mHidden; 452 453 // Set to true when the app has requested that this fragment be detached. 454 boolean mDetached; 455 456 // If set this fragment would like its instance retained across 457 // configuration changes. 458 boolean mRetainInstance; 459 460 // If set this fragment is being retained across the current config change. 461 boolean mRetaining; 462 463 // If set this fragment has menu items to contribute. 464 boolean mHasMenu; 465 466 // Set to true to allow the fragment's menu to be shown. 467 boolean mMenuVisible = true; 468 469 // Used to verify that subclasses call through to super class. 470 boolean mCalled; 471 472 // If app has requested a specific animation, this is the one to use. 473 int mNextAnim; 474 475 // The parent container of the fragment after dynamically added to UI. 476 ViewGroup mContainer; 477 478 // The View generated for this fragment. 479 View mView; 480 481 // Whether this fragment should defer starting until after other fragments 482 // have been started and their loaders are finished. 483 boolean mDeferStart; 484 485 // Hint provided by the app that this fragment is currently visible to the user. 486 boolean mUserVisibleHint = true; 487 488 LoaderManagerImpl mLoaderManager; 489 boolean mLoadersStarted; 490 boolean mCheckedForLoaderManager; 491 492 private Transition mEnterTransition = null; 493 private Transition mReturnTransition = USE_DEFAULT_TRANSITION; 494 private Transition mExitTransition = null; 495 private Transition mReenterTransition = USE_DEFAULT_TRANSITION; 496 private Transition mSharedElementEnterTransition = null; 497 private Transition mSharedElementReturnTransition = USE_DEFAULT_TRANSITION; 498 private Boolean mAllowReturnTransitionOverlap; 499 private Boolean mAllowEnterTransitionOverlap; 500 501 SharedElementCallback mEnterTransitionCallback = SharedElementCallback.NULL_CALLBACK; 502 SharedElementCallback mExitTransitionCallback = SharedElementCallback.NULL_CALLBACK; 503 504 /** 505 * State information that has been retrieved from a fragment instance 506 * through {@link FragmentManager#saveFragmentInstanceState(Fragment) 507 * FragmentManager.saveFragmentInstanceState}. 508 */ 509 public static class SavedState implements Parcelable { 510 final Bundle mState; 511 512 SavedState(Bundle state) { 513 mState = state; 514 } 515 516 SavedState(Parcel in, ClassLoader loader) { 517 mState = in.readBundle(); 518 if (loader != null && mState != null) { 519 mState.setClassLoader(loader); 520 } 521 } 522 523 @Override 524 public int describeContents() { 525 return 0; 526 } 527 528 @Override 529 public void writeToParcel(Parcel dest, int flags) { 530 dest.writeBundle(mState); 531 } 532 533 public static final Parcelable.ClassLoaderCreator<SavedState> CREATOR 534 = new Parcelable.ClassLoaderCreator<SavedState>() { 535 public SavedState createFromParcel(Parcel in) { 536 return new SavedState(in, null); 537 } 538 539 public SavedState createFromParcel(Parcel in, ClassLoader loader) { 540 return new SavedState(in, loader); 541 } 542 543 public SavedState[] newArray(int size) { 544 return new SavedState[size]; 545 } 546 }; 547 } 548 549 /** 550 * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when 551 * there is an instantiation failure. 552 */ 553 static public class InstantiationException extends AndroidRuntimeException { 554 public InstantiationException(String msg, Exception cause) { 555 super(msg, cause); 556 } 557 } 558 559 /** 560 * Default constructor. <strong>Every</strong> fragment must have an 561 * empty constructor, so it can be instantiated when restoring its 562 * activity's state. It is strongly recommended that subclasses do not 563 * have other constructors with parameters, since these constructors 564 * will not be called when the fragment is re-instantiated; instead, 565 * arguments can be supplied by the caller with {@link #setArguments} 566 * and later retrieved by the Fragment with {@link #getArguments}. 567 * 568 * <p>Applications should generally not implement a constructor. The 569 * first place application code can run where the fragment is ready to 570 * be used is in {@link #onAttach(Activity)}, the point where the fragment 571 * is actually associated with its activity. Some applications may also 572 * want to implement {@link #onInflate} to retrieve attributes from a 573 * layout resource, though should take care here because this happens for 574 * the fragment is attached to its activity. 575 */ 576 public Fragment() { 577 } 578 579 /** 580 * Like {@link #instantiate(Context, String, Bundle)} but with a null 581 * argument Bundle. 582 */ 583 public static Fragment instantiate(Context context, String fname) { 584 return instantiate(context, fname, null); 585 } 586 587 /** 588 * Create a new instance of a Fragment with the given class name. This is 589 * the same as calling its empty constructor. 590 * 591 * @param context The calling context being used to instantiate the fragment. 592 * This is currently just used to get its ClassLoader. 593 * @param fname The class name of the fragment to instantiate. 594 * @param args Bundle of arguments to supply to the fragment, which it 595 * can retrieve with {@link #getArguments()}. May be null. 596 * @return Returns a new fragment instance. 597 * @throws InstantiationException If there is a failure in instantiating 598 * the given fragment class. This is a runtime exception; it is not 599 * normally expected to happen. 600 */ 601 public static Fragment instantiate(Context context, String fname, @Nullable Bundle args) { 602 try { 603 Class<?> clazz = sClassMap.get(fname); 604 if (clazz == null) { 605 // Class not found in the cache, see if it's real, and try to add it 606 clazz = context.getClassLoader().loadClass(fname); 607 if (!Fragment.class.isAssignableFrom(clazz)) { 608 throw new InstantiationException("Trying to instantiate a class " + fname 609 + " that is not a Fragment", new ClassCastException()); 610 } 611 sClassMap.put(fname, clazz); 612 } 613 Fragment f = (Fragment)clazz.newInstance(); 614 if (args != null) { 615 args.setClassLoader(f.getClass().getClassLoader()); 616 f.mArguments = args; 617 } 618 return f; 619 } catch (ClassNotFoundException e) { 620 throw new InstantiationException("Unable to instantiate fragment " + fname 621 + ": make sure class name exists, is public, and has an" 622 + " empty constructor that is public", e); 623 } catch (java.lang.InstantiationException e) { 624 throw new InstantiationException("Unable to instantiate fragment " + fname 625 + ": make sure class name exists, is public, and has an" 626 + " empty constructor that is public", e); 627 } catch (IllegalAccessException e) { 628 throw new InstantiationException("Unable to instantiate fragment " + fname 629 + ": make sure class name exists, is public, and has an" 630 + " empty constructor that is public", e); 631 } 632 } 633 634 final void restoreViewState(Bundle savedInstanceState) { 635 if (mSavedViewState != null) { 636 mView.restoreHierarchyState(mSavedViewState); 637 mSavedViewState = null; 638 } 639 mCalled = false; 640 onViewStateRestored(savedInstanceState); 641 if (!mCalled) { 642 throw new SuperNotCalledException("Fragment " + this 643 + " did not call through to super.onViewStateRestored()"); 644 } 645 } 646 647 final void setIndex(int index, Fragment parent) { 648 mIndex = index; 649 if (parent != null) { 650 mWho = parent.mWho + ":" + mIndex; 651 } else { 652 mWho = "android:fragment:" + mIndex; 653 } 654 } 655 656 final boolean isInBackStack() { 657 return mBackStackNesting > 0; 658 } 659 660 /** 661 * Subclasses can not override equals(). 662 */ 663 @Override final public boolean equals(Object o) { 664 return super.equals(o); 665 } 666 667 /** 668 * Subclasses can not override hashCode(). 669 */ 670 @Override final public int hashCode() { 671 return super.hashCode(); 672 } 673 674 @Override 675 public String toString() { 676 StringBuilder sb = new StringBuilder(128); 677 DebugUtils.buildShortClassTag(this, sb); 678 if (mIndex >= 0) { 679 sb.append(" #"); 680 sb.append(mIndex); 681 } 682 if (mFragmentId != 0) { 683 sb.append(" id=0x"); 684 sb.append(Integer.toHexString(mFragmentId)); 685 } 686 if (mTag != null) { 687 sb.append(" "); 688 sb.append(mTag); 689 } 690 sb.append('}'); 691 return sb.toString(); 692 } 693 694 /** 695 * Return the identifier this fragment is known by. This is either 696 * the android:id value supplied in a layout or the container view ID 697 * supplied when adding the fragment. 698 */ 699 final public int getId() { 700 return mFragmentId; 701 } 702 703 /** 704 * Get the tag name of the fragment, if specified. 705 */ 706 final public String getTag() { 707 return mTag; 708 } 709 710 /** 711 * Supply the construction arguments for this fragment. This can only 712 * be called before the fragment has been attached to its activity; that 713 * is, you should call it immediately after constructing the fragment. The 714 * arguments supplied here will be retained across fragment destroy and 715 * creation. 716 */ 717 public void setArguments(Bundle args) { 718 if (mIndex >= 0) { 719 throw new IllegalStateException("Fragment already active"); 720 } 721 mArguments = args; 722 } 723 724 /** 725 * Return the arguments supplied to {@link #setArguments}, if any. 726 */ 727 final public Bundle getArguments() { 728 return mArguments; 729 } 730 731 /** 732 * Set the initial saved state that this Fragment should restore itself 733 * from when first being constructed, as returned by 734 * {@link FragmentManager#saveFragmentInstanceState(Fragment) 735 * FragmentManager.saveFragmentInstanceState}. 736 * 737 * @param state The state the fragment should be restored from. 738 */ 739 public void setInitialSavedState(SavedState state) { 740 if (mIndex >= 0) { 741 throw new IllegalStateException("Fragment already active"); 742 } 743 mSavedFragmentState = state != null && state.mState != null 744 ? state.mState : null; 745 } 746 747 /** 748 * Optional target for this fragment. This may be used, for example, 749 * if this fragment is being started by another, and when done wants to 750 * give a result back to the first. The target set here is retained 751 * across instances via {@link FragmentManager#putFragment 752 * FragmentManager.putFragment()}. 753 * 754 * @param fragment The fragment that is the target of this one. 755 * @param requestCode Optional request code, for convenience if you 756 * are going to call back with {@link #onActivityResult(int, int, Intent)}. 757 */ 758 public void setTargetFragment(Fragment fragment, int requestCode) { 759 mTarget = fragment; 760 mTargetRequestCode = requestCode; 761 } 762 763 /** 764 * Return the target fragment set by {@link #setTargetFragment}. 765 */ 766 final public Fragment getTargetFragment() { 767 return mTarget; 768 } 769 770 /** 771 * Return the target request code set by {@link #setTargetFragment}. 772 */ 773 final public int getTargetRequestCode() { 774 return mTargetRequestCode; 775 } 776 777 /** 778 * Return the {@link Context} this fragment is currently associated with. 779 */ 780 public Context getContext() { 781 return mHost == null ? null : mHost.getContext(); 782 } 783 784 /** 785 * Return the Activity this fragment is currently associated with. 786 */ 787 final public Activity getActivity() { 788 return mHost == null ? null : mHost.getActivity(); 789 } 790 791 /** 792 * Return the host object of this fragment. May return {@code null} if the fragment 793 * isn't currently being hosted. 794 */ 795 @Nullable 796 final public Object getHost() { 797 return mHost == null ? null : mHost.onGetHost(); 798 } 799 800 /** 801 * Return <code>getActivity().getResources()</code>. 802 */ 803 final public Resources getResources() { 804 if (mHost == null) { 805 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 806 } 807 return mHost.getContext().getResources(); 808 } 809 810 /** 811 * Return a localized, styled CharSequence from the application's package's 812 * default string table. 813 * 814 * @param resId Resource id for the CharSequence text 815 */ 816 public final CharSequence getText(@StringRes int resId) { 817 return getResources().getText(resId); 818 } 819 820 /** 821 * Return a localized string from the application's package's 822 * default string table. 823 * 824 * @param resId Resource id for the string 825 */ 826 public final String getString(@StringRes int resId) { 827 return getResources().getString(resId); 828 } 829 830 /** 831 * Return a localized formatted string from the application's package's 832 * default string table, substituting the format arguments as defined in 833 * {@link java.util.Formatter} and {@link java.lang.String#format}. 834 * 835 * @param resId Resource id for the format string 836 * @param formatArgs The format arguments that will be used for substitution. 837 */ 838 839 public final String getString(@StringRes int resId, Object... formatArgs) { 840 return getResources().getString(resId, formatArgs); 841 } 842 843 /** 844 * Return the FragmentManager for interacting with fragments associated 845 * with this fragment's activity. Note that this will be non-null slightly 846 * before {@link #getActivity()}, during the time from when the fragment is 847 * placed in a {@link FragmentTransaction} until it is committed and 848 * attached to its activity. 849 * 850 * <p>If this Fragment is a child of another Fragment, the FragmentManager 851 * returned here will be the parent's {@link #getChildFragmentManager()}. 852 */ 853 final public FragmentManager getFragmentManager() { 854 return mFragmentManager; 855 } 856 857 /** 858 * Return a private FragmentManager for placing and managing Fragments 859 * inside of this Fragment. 860 */ 861 final public FragmentManager getChildFragmentManager() { 862 if (mChildFragmentManager == null) { 863 instantiateChildFragmentManager(); 864 if (mState >= RESUMED) { 865 mChildFragmentManager.dispatchResume(); 866 } else if (mState >= STARTED) { 867 mChildFragmentManager.dispatchStart(); 868 } else if (mState >= ACTIVITY_CREATED) { 869 mChildFragmentManager.dispatchActivityCreated(); 870 } else if (mState >= CREATED) { 871 mChildFragmentManager.dispatchCreate(); 872 } 873 } 874 return mChildFragmentManager; 875 } 876 877 /** 878 * Returns the parent Fragment containing this Fragment. If this Fragment 879 * is attached directly to an Activity, returns null. 880 */ 881 final public Fragment getParentFragment() { 882 return mParentFragment; 883 } 884 885 /** 886 * Return true if the fragment is currently added to its activity. 887 */ 888 final public boolean isAdded() { 889 return mHost != null && mAdded; 890 } 891 892 /** 893 * Return true if the fragment has been explicitly detached from the UI. 894 * That is, {@link FragmentTransaction#detach(Fragment) 895 * FragmentTransaction.detach(Fragment)} has been used on it. 896 */ 897 final public boolean isDetached() { 898 return mDetached; 899 } 900 901 /** 902 * Return true if this fragment is currently being removed from its 903 * activity. This is <em>not</em> whether its activity is finishing, but 904 * rather whether it is in the process of being removed from its activity. 905 */ 906 final public boolean isRemoving() { 907 return mRemoving; 908 } 909 910 /** 911 * Return true if the layout is included as part of an activity view 912 * hierarchy via the <fragment> tag. This will always be true when 913 * fragments are created through the <fragment> tag, <em>except</em> 914 * in the case where an old fragment is restored from a previous state and 915 * it does not appear in the layout of the current state. 916 */ 917 final public boolean isInLayout() { 918 return mInLayout; 919 } 920 921 /** 922 * Return true if the fragment is in the resumed state. This is true 923 * for the duration of {@link #onResume()} and {@link #onPause()} as well. 924 */ 925 final public boolean isResumed() { 926 return mResumed; 927 } 928 929 /** 930 * Return true if the fragment is currently visible to the user. This means 931 * it: (1) has been added, (2) has its view attached to the window, and 932 * (3) is not hidden. 933 */ 934 final public boolean isVisible() { 935 return isAdded() && !isHidden() && mView != null 936 && mView.getWindowToken() != null && mView.getVisibility() == View.VISIBLE; 937 } 938 939 /** 940 * Return true if the fragment has been hidden. By default fragments 941 * are shown. You can find out about changes to this state with 942 * {@link #onHiddenChanged}. Note that the hidden state is orthogonal 943 * to other states -- that is, to be visible to the user, a fragment 944 * must be both started and not hidden. 945 */ 946 final public boolean isHidden() { 947 return mHidden; 948 } 949 950 /** 951 * Called when the hidden state (as returned by {@link #isHidden()} of 952 * the fragment has changed. Fragments start out not hidden; this will 953 * be called whenever the fragment changes state from that. 954 * @param hidden True if the fragment is now hidden, false if it is not 955 * visible. 956 */ 957 public void onHiddenChanged(boolean hidden) { 958 } 959 960 /** 961 * Control whether a fragment instance is retained across Activity 962 * re-creation (such as from a configuration change). This can only 963 * be used with fragments not in the back stack. If set, the fragment 964 * lifecycle will be slightly different when an activity is recreated: 965 * <ul> 966 * <li> {@link #onDestroy()} will not be called (but {@link #onDetach()} still 967 * will be, because the fragment is being detached from its current activity). 968 * <li> {@link #onCreate(Bundle)} will not be called since the fragment 969 * is not being re-created. 970 * <li> {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} <b>will</b> 971 * still be called. 972 * </ul> 973 */ 974 public void setRetainInstance(boolean retain) { 975 if (retain && mParentFragment != null) { 976 throw new IllegalStateException( 977 "Can't retain fragements that are nested in other fragments"); 978 } 979 mRetainInstance = retain; 980 } 981 982 final public boolean getRetainInstance() { 983 return mRetainInstance; 984 } 985 986 /** 987 * Report that this fragment would like to participate in populating 988 * the options menu by receiving a call to {@link #onCreateOptionsMenu} 989 * and related methods. 990 * 991 * @param hasMenu If true, the fragment has menu items to contribute. 992 */ 993 public void setHasOptionsMenu(boolean hasMenu) { 994 if (mHasMenu != hasMenu) { 995 mHasMenu = hasMenu; 996 if (isAdded() && !isHidden()) { 997 mFragmentManager.invalidateOptionsMenu(); 998 } 999 } 1000 } 1001 1002 /** 1003 * Set a hint for whether this fragment's menu should be visible. This 1004 * is useful if you know that a fragment has been placed in your view 1005 * hierarchy so that the user can not currently seen it, so any menu items 1006 * it has should also not be shown. 1007 * 1008 * @param menuVisible The default is true, meaning the fragment's menu will 1009 * be shown as usual. If false, the user will not see the menu. 1010 */ 1011 public void setMenuVisibility(boolean menuVisible) { 1012 if (mMenuVisible != menuVisible) { 1013 mMenuVisible = menuVisible; 1014 if (mHasMenu && isAdded() && !isHidden()) { 1015 mFragmentManager.invalidateOptionsMenu(); 1016 } 1017 } 1018 } 1019 1020 /** 1021 * Set a hint to the system about whether this fragment's UI is currently visible 1022 * to the user. This hint defaults to true and is persistent across fragment instance 1023 * state save and restore. 1024 * 1025 * <p>An app may set this to false to indicate that the fragment's UI is 1026 * scrolled out of visibility or is otherwise not directly visible to the user. 1027 * This may be used by the system to prioritize operations such as fragment lifecycle updates 1028 * or loader ordering behavior.</p> 1029 * 1030 * @param isVisibleToUser true if this fragment's UI is currently visible to the user (default), 1031 * false if it is not. 1032 */ 1033 public void setUserVisibleHint(boolean isVisibleToUser) { 1034 if (!mUserVisibleHint && isVisibleToUser && mState < STARTED) { 1035 mFragmentManager.performPendingDeferredStart(this); 1036 } 1037 mUserVisibleHint = isVisibleToUser; 1038 mDeferStart = !isVisibleToUser; 1039 } 1040 1041 /** 1042 * @return The current value of the user-visible hint on this fragment. 1043 * @see #setUserVisibleHint(boolean) 1044 */ 1045 public boolean getUserVisibleHint() { 1046 return mUserVisibleHint; 1047 } 1048 1049 /** 1050 * Return the LoaderManager for this fragment, creating it if needed. 1051 */ 1052 public LoaderManager getLoaderManager() { 1053 if (mLoaderManager != null) { 1054 return mLoaderManager; 1055 } 1056 if (mHost == null) { 1057 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1058 } 1059 mCheckedForLoaderManager = true; 1060 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, true); 1061 return mLoaderManager; 1062 } 1063 1064 /** 1065 * Call {@link Activity#startActivity(Intent)} from the fragment's 1066 * containing Activity. 1067 * 1068 * @param intent The intent to start. 1069 */ 1070 public void startActivity(Intent intent) { 1071 startActivity(intent, null); 1072 } 1073 1074 /** 1075 * Call {@link Activity#startActivity(Intent, Bundle)} from the fragment's 1076 * containing Activity. 1077 * 1078 * @param intent The intent to start. 1079 * @param options Additional options for how the Activity should be started. 1080 * See {@link android.content.Context#startActivity(Intent, Bundle) 1081 * Context.startActivity(Intent, Bundle)} for more details. 1082 */ 1083 public void startActivity(Intent intent, Bundle options) { 1084 if (mHost == null) { 1085 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1086 } 1087 if (options != null) { 1088 mHost.onStartActivityFromFragment(this, intent, -1, options); 1089 } else { 1090 // Note we want to go through this call for compatibility with 1091 // applications that may have overridden the method. 1092 mHost.onStartActivityFromFragment(this, intent, -1, null /*options*/); 1093 } 1094 } 1095 1096 /** 1097 * Call {@link Activity#startActivityForResult(Intent, int)} from the fragment's 1098 * containing Activity. 1099 */ 1100 public void startActivityForResult(Intent intent, int requestCode) { 1101 startActivityForResult(intent, requestCode, null); 1102 } 1103 1104 /** 1105 * Call {@link Activity#startActivityForResult(Intent, int, Bundle)} from the fragment's 1106 * containing Activity. 1107 */ 1108 public void startActivityForResult(Intent intent, int requestCode, Bundle options) { 1109 if (mHost == null) { 1110 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1111 } 1112 mHost.onStartActivityFromFragment(this, intent, requestCode, options); 1113 } 1114 1115 /** 1116 * Receive the result from a previous call to 1117 * {@link #startActivityForResult(Intent, int)}. This follows the 1118 * related Activity API as described there in 1119 * {@link Activity#onActivityResult(int, int, Intent)}. 1120 * 1121 * @param requestCode The integer request code originally supplied to 1122 * startActivityForResult(), allowing you to identify who this 1123 * result came from. 1124 * @param resultCode The integer result code returned by the child activity 1125 * through its setResult(). 1126 * @param data An Intent, which can return result data to the caller 1127 * (various data can be attached to Intent "extras"). 1128 */ 1129 public void onActivityResult(int requestCode, int resultCode, Intent data) { 1130 } 1131 1132 /** 1133 * Requests permissions to be granted to this application. These permissions 1134 * must be requested in your manifest, they should not be granted to your app, 1135 * and they should have protection level {@link android.content.pm.PermissionInfo 1136 * #PROTECTION_DANGEROUS dangerous}, regardless whether they are declared by 1137 * the platform or a third-party app. 1138 * <p> 1139 * Normal permissions {@link android.content.pm.PermissionInfo#PROTECTION_NORMAL} 1140 * are granted at install time if requested in the manifest. Signature permissions 1141 * {@link android.content.pm.PermissionInfo#PROTECTION_SIGNATURE} are granted at 1142 * install time if requested in the manifest and the signature of your app matches 1143 * the signature of the app declaring the permissions. 1144 * </p> 1145 * <p> 1146 * If your app does not have the requested permissions the user will be presented 1147 * with UI for accepting them. After the user has accepted or rejected the 1148 * requested permissions you will receive a callback on {@link 1149 * #onRequestPermissionsResult(int, String[], int[])} reporting whether the 1150 * permissions were granted or not. 1151 * </p> 1152 * <p> 1153 * Note that requesting a permission does not guarantee it will be granted and 1154 * your app should be able to run without having this permission. 1155 * </p> 1156 * <p> 1157 * This method may start an activity allowing the user to choose which permissions 1158 * to grant and which to reject. Hence, you should be prepared that your activity 1159 * may be paused and resumed. Further, granting some permissions may require 1160 * a restart of you application. In such a case, the system will recreate the 1161 * activity stack before delivering the result to {@link 1162 * #onRequestPermissionsResult(int, String[], int[])}. 1163 * </p> 1164 * <p> 1165 * When checking whether you have a permission you should use {@link 1166 * android.content.Context#checkSelfPermission(String)}. 1167 * </p> 1168 * <p> 1169 * You cannot request a permission if your activity sets {@link 1170 * android.R.styleable#AndroidManifestActivity_noHistory noHistory} to 1171 * <code>true</code> because in this case the activity would not receive 1172 * result callbacks including {@link #onRequestPermissionsResult(int, String[], int[])}. 1173 * </p> 1174 * <p> 1175 * A sample permissions request looks like this: 1176 * </p> 1177 * <code><pre><p> 1178 * private void showContacts() { 1179 * if (getActivity().checkSelfPermission(Manifest.permission.READ_CONTACTS) 1180 * != PackageManager.PERMISSION_GRANTED) { 1181 * requestPermissions(new String[]{Manifest.permission.READ_CONTACTS}, 1182 * PERMISSIONS_REQUEST_READ_CONTACTS); 1183 * } else { 1184 * doShowContacts(); 1185 * } 1186 * } 1187 * 1188 * {@literal @}Override 1189 * public void onRequestPermissionsResult(int requestCode, String[] permissions, 1190 * int[] grantResults) { 1191 * if (requestCode == PERMISSIONS_REQUEST_READ_CONTACTS 1192 * && grantResults[0] == PackageManager.PERMISSION_GRANTED) { 1193 * doShowContacts(); 1194 * } 1195 * } 1196 * </code></pre></p> 1197 * 1198 * @param permissions The requested permissions. 1199 * @param requestCode Application specific request code to match with a result 1200 * reported to {@link #onRequestPermissionsResult(int, String[], int[])}. 1201 * Should be >= 0. 1202 * 1203 * @see #onRequestPermissionsResult(int, String[], int[]) 1204 * @see android.content.Context#checkSelfPermission(String) 1205 */ 1206 public final void requestPermissions(@NonNull String[] permissions, int requestCode) { 1207 if (mHost == null) { 1208 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 1209 } 1210 mHost.onRequestPermissionsFromFragment(this, permissions,requestCode); 1211 } 1212 1213 /** 1214 * Callback for the result from requesting permissions. This method 1215 * is invoked for every call on {@link #requestPermissions(String[], int)}. 1216 * 1217 * @param requestCode The request code passed in {@link #requestPermissions(String[], int)}. 1218 * @param permissions The requested permissions. Never null. 1219 * @param grantResults The grant results for the corresponding permissions 1220 * which is either {@link android.content.pm.PackageManager#PERMISSION_GRANTED} 1221 * or {@link android.content.pm.PackageManager#PERMISSION_DENIED}. Never null. 1222 * 1223 * @see #requestPermissions(String[], int) 1224 */ 1225 public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, 1226 @NonNull int[] grantResults) { 1227 /* callback - do nothing */ 1228 } 1229 1230 /** 1231 * Gets whether you should show UI with rationale for requesting a permission. 1232 * You should do this only if you do not have the permission and the context in 1233 * which the permission is requested does not clearly communicate to the user 1234 * what would be the benefit from granting this permission. 1235 * <p> 1236 * For example, if you write a camera app, requesting the camera permission 1237 * would be expected by the user and no rationale for why it is requested is 1238 * needed. If however, the app needs location for tagging photos then a non-tech 1239 * savvy user may wonder how location is related to taking photos. In this case 1240 * you may choose to show UI with rationale of requesting this permission. 1241 * </p> 1242 * 1243 * @param permission A permission your app wants to request. 1244 * @return Whether you can show permission rationale UI. 1245 * 1246 * @see Context#checkSelfPermission(String) 1247 * @see #requestPermissions(String[], int) 1248 * @see #onRequestPermissionsResult(int, String[], int[]) 1249 */ 1250 public boolean shouldShowRequestPermissionRationale(@NonNull String permission) { 1251 if (mHost != null) { 1252 return mHost.getContext().getPackageManager() 1253 .shouldShowRequestPermissionRationale(permission); 1254 } 1255 return false; 1256 } 1257 1258 /** 1259 * @hide Hack so that DialogFragment can make its Dialog before creating 1260 * its views, and the view construction can use the dialog's context for 1261 * inflation. Maybe this should become a public API. Note sure. 1262 */ 1263 public LayoutInflater getLayoutInflater(Bundle savedInstanceState) { 1264 final LayoutInflater result = mHost.onGetLayoutInflater(); 1265 if (mHost.onUseFragmentManagerInflaterFactory()) { 1266 getChildFragmentManager(); // Init if needed; use raw implementation below. 1267 result.setPrivateFactory(mChildFragmentManager.getLayoutInflaterFactory()); 1268 } 1269 return result; 1270 } 1271 1272 /** 1273 * @deprecated Use {@link #onInflate(Context, AttributeSet, Bundle)} instead. 1274 */ 1275 @Deprecated 1276 public void onInflate(AttributeSet attrs, Bundle savedInstanceState) { 1277 mCalled = true; 1278 } 1279 1280 /** 1281 * Called when a fragment is being created as part of a view layout 1282 * inflation, typically from setting the content view of an activity. This 1283 * may be called immediately after the fragment is created from a <fragment> 1284 * tag in a layout file. Note this is <em>before</em> the fragment's 1285 * {@link #onAttach(Activity)} has been called; all you should do here is 1286 * parse the attributes and save them away. 1287 * 1288 * <p>This is called every time the fragment is inflated, even if it is 1289 * being inflated into a new instance with saved state. It typically makes 1290 * sense to re-parse the parameters each time, to allow them to change with 1291 * different configurations.</p> 1292 * 1293 * <p>Here is a typical implementation of a fragment that can take parameters 1294 * both through attributes supplied here as well from {@link #getArguments()}:</p> 1295 * 1296 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1297 * fragment} 1298 * 1299 * <p>Note that parsing the XML attributes uses a "styleable" resource. The 1300 * declaration for the styleable used here is:</p> 1301 * 1302 * {@sample development/samples/ApiDemos/res/values/attrs.xml fragment_arguments} 1303 * 1304 * <p>The fragment can then be declared within its activity's content layout 1305 * through a tag like this:</p> 1306 * 1307 * {@sample development/samples/ApiDemos/res/layout/fragment_arguments.xml from_attributes} 1308 * 1309 * <p>This fragment can also be created dynamically from arguments given 1310 * at runtime in the arguments Bundle; here is an example of doing so at 1311 * creation of the containing activity:</p> 1312 * 1313 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1314 * create} 1315 * 1316 * @param context The Context that is inflating this fragment. 1317 * @param attrs The attributes at the tag where the fragment is 1318 * being created. 1319 * @param savedInstanceState If the fragment is being re-created from 1320 * a previous saved state, this is the state. 1321 */ 1322 public void onInflate(Context context, AttributeSet attrs, Bundle savedInstanceState) { 1323 onInflate(attrs, savedInstanceState); 1324 mCalled = true; 1325 1326 TypedArray a = context.obtainStyledAttributes(attrs, 1327 com.android.internal.R.styleable.Fragment); 1328 mEnterTransition = loadTransition(context, a, mEnterTransition, null, 1329 com.android.internal.R.styleable.Fragment_fragmentEnterTransition); 1330 mReturnTransition = loadTransition(context, a, mReturnTransition, USE_DEFAULT_TRANSITION, 1331 com.android.internal.R.styleable.Fragment_fragmentReturnTransition); 1332 mExitTransition = loadTransition(context, a, mExitTransition, null, 1333 com.android.internal.R.styleable.Fragment_fragmentExitTransition); 1334 mReenterTransition = loadTransition(context, a, mReenterTransition, USE_DEFAULT_TRANSITION, 1335 com.android.internal.R.styleable.Fragment_fragmentReenterTransition); 1336 mSharedElementEnterTransition = loadTransition(context, a, mSharedElementEnterTransition, 1337 null, com.android.internal.R.styleable.Fragment_fragmentSharedElementEnterTransition); 1338 mSharedElementReturnTransition = loadTransition(context, a, mSharedElementReturnTransition, 1339 USE_DEFAULT_TRANSITION, 1340 com.android.internal.R.styleable.Fragment_fragmentSharedElementReturnTransition); 1341 if (mAllowEnterTransitionOverlap == null) { 1342 mAllowEnterTransitionOverlap = a.getBoolean( 1343 com.android.internal.R.styleable.Fragment_fragmentAllowEnterTransitionOverlap, true); 1344 } 1345 if (mAllowReturnTransitionOverlap == null) { 1346 mAllowReturnTransitionOverlap = a.getBoolean( 1347 com.android.internal.R.styleable.Fragment_fragmentAllowReturnTransitionOverlap, true); 1348 } 1349 a.recycle(); 1350 1351 final Activity hostActivity = mHost == null ? null : mHost.getActivity(); 1352 if (hostActivity != null) { 1353 mCalled = false; 1354 onInflate(hostActivity, attrs, savedInstanceState); 1355 } 1356 } 1357 1358 /** 1359 * @deprecated Use {@link #onInflate(Context, AttributeSet, Bundle)} instead. 1360 */ 1361 @Deprecated 1362 public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) { 1363 mCalled = true; 1364 } 1365 1366 /** 1367 * Called when a fragment is first attached to its context. 1368 * {@link #onCreate(Bundle)} will be called after this. 1369 */ 1370 public void onAttach(Context context) { 1371 mCalled = true; 1372 final Activity hostActivity = mHost == null ? null : mHost.getActivity(); 1373 if (hostActivity != null) { 1374 mCalled = false; 1375 onAttach(hostActivity); 1376 } 1377 } 1378 1379 /** 1380 * @deprecated Use {@link #onAttach(Context)} instead. 1381 */ 1382 @Deprecated 1383 public void onAttach(Activity activity) { 1384 mCalled = true; 1385 } 1386 1387 /** 1388 * Called when a fragment loads an animation. 1389 */ 1390 public Animator onCreateAnimator(int transit, boolean enter, int nextAnim) { 1391 return null; 1392 } 1393 1394 /** 1395 * Called to do initial creation of a fragment. This is called after 1396 * {@link #onAttach(Activity)} and before 1397 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 1398 * 1399 * <p>Note that this can be called while the fragment's activity is 1400 * still in the process of being created. As such, you can not rely 1401 * on things like the activity's content view hierarchy being initialized 1402 * at this point. If you want to do work once the activity itself is 1403 * created, see {@link #onActivityCreated(Bundle)}. 1404 * 1405 * @param savedInstanceState If the fragment is being re-created from 1406 * a previous saved state, this is the state. 1407 */ 1408 public void onCreate(@Nullable Bundle savedInstanceState) { 1409 mCalled = true; 1410 } 1411 1412 /** 1413 * Called to have the fragment instantiate its user interface view. 1414 * This is optional, and non-graphical fragments can return null (which 1415 * is the default implementation). This will be called between 1416 * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}. 1417 * 1418 * <p>If you return a View from here, you will later be called in 1419 * {@link #onDestroyView} when the view is being released. 1420 * 1421 * @param inflater The LayoutInflater object that can be used to inflate 1422 * any views in the fragment, 1423 * @param container If non-null, this is the parent view that the fragment's 1424 * UI should be attached to. The fragment should not add the view itself, 1425 * but this can be used to generate the LayoutParams of the view. 1426 * @param savedInstanceState If non-null, this fragment is being re-constructed 1427 * from a previous saved state as given here. 1428 * 1429 * @return Return the View for the fragment's UI, or null. 1430 */ 1431 @Nullable 1432 public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, 1433 Bundle savedInstanceState) { 1434 return null; 1435 } 1436 1437 /** 1438 * Called immediately after {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} 1439 * has returned, but before any saved state has been restored in to the view. 1440 * This gives subclasses a chance to initialize themselves once 1441 * they know their view hierarchy has been completely created. The fragment's 1442 * view hierarchy is not however attached to its parent at this point. 1443 * @param view The View returned by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 1444 * @param savedInstanceState If non-null, this fragment is being re-constructed 1445 * from a previous saved state as given here. 1446 */ 1447 public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { 1448 } 1449 1450 /** 1451 * Get the root view for the fragment's layout (the one returned by {@link #onCreateView}), 1452 * if provided. 1453 * 1454 * @return The fragment's root view, or null if it has no layout. 1455 */ 1456 @Nullable 1457 public View getView() { 1458 return mView; 1459 } 1460 1461 /** 1462 * Called when the fragment's activity has been created and this 1463 * fragment's view hierarchy instantiated. It can be used to do final 1464 * initialization once these pieces are in place, such as retrieving 1465 * views or restoring state. It is also useful for fragments that use 1466 * {@link #setRetainInstance(boolean)} to retain their instance, 1467 * as this callback tells the fragment when it is fully associated with 1468 * the new activity instance. This is called after {@link #onCreateView} 1469 * and before {@link #onViewStateRestored(Bundle)}. 1470 * 1471 * @param savedInstanceState If the fragment is being re-created from 1472 * a previous saved state, this is the state. 1473 */ 1474 public void onActivityCreated(@Nullable Bundle savedInstanceState) { 1475 mCalled = true; 1476 } 1477 1478 /** 1479 * Called when all saved state has been restored into the view hierarchy 1480 * of the fragment. This can be used to do initialization based on saved 1481 * state that you are letting the view hierarchy track itself, such as 1482 * whether check box widgets are currently checked. This is called 1483 * after {@link #onActivityCreated(Bundle)} and before 1484 * {@link #onStart()}. 1485 * 1486 * @param savedInstanceState If the fragment is being re-created from 1487 * a previous saved state, this is the state. 1488 */ 1489 public void onViewStateRestored(Bundle savedInstanceState) { 1490 mCalled = true; 1491 } 1492 1493 /** 1494 * Called when the Fragment is visible to the user. This is generally 1495 * tied to {@link Activity#onStart() Activity.onStart} of the containing 1496 * Activity's lifecycle. 1497 */ 1498 public void onStart() { 1499 mCalled = true; 1500 1501 if (!mLoadersStarted) { 1502 mLoadersStarted = true; 1503 if (!mCheckedForLoaderManager) { 1504 mCheckedForLoaderManager = true; 1505 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 1506 } 1507 if (mLoaderManager != null) { 1508 mLoaderManager.doStart(); 1509 } 1510 } 1511 } 1512 1513 /** 1514 * Called when the fragment is visible to the user and actively running. 1515 * This is generally 1516 * tied to {@link Activity#onResume() Activity.onResume} of the containing 1517 * Activity's lifecycle. 1518 */ 1519 public void onResume() { 1520 mCalled = true; 1521 } 1522 1523 /** 1524 * Called to ask the fragment to save its current dynamic state, so it 1525 * can later be reconstructed in a new instance of its process is 1526 * restarted. If a new instance of the fragment later needs to be 1527 * created, the data you place in the Bundle here will be available 1528 * in the Bundle given to {@link #onCreate(Bundle)}, 1529 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, and 1530 * {@link #onActivityCreated(Bundle)}. 1531 * 1532 * <p>This corresponds to {@link Activity#onSaveInstanceState(Bundle) 1533 * Activity.onSaveInstanceState(Bundle)} and most of the discussion there 1534 * applies here as well. Note however: <em>this method may be called 1535 * at any time before {@link #onDestroy()}</em>. There are many situations 1536 * where a fragment may be mostly torn down (such as when placed on the 1537 * back stack with no UI showing), but its state will not be saved until 1538 * its owning activity actually needs to save its state. 1539 * 1540 * @param outState Bundle in which to place your saved state. 1541 */ 1542 public void onSaveInstanceState(Bundle outState) { 1543 } 1544 1545 public void onConfigurationChanged(Configuration newConfig) { 1546 mCalled = true; 1547 } 1548 1549 /** 1550 * Called when the Fragment is no longer resumed. This is generally 1551 * tied to {@link Activity#onPause() Activity.onPause} of the containing 1552 * Activity's lifecycle. 1553 */ 1554 public void onPause() { 1555 mCalled = true; 1556 } 1557 1558 /** 1559 * Called when the Fragment is no longer started. This is generally 1560 * tied to {@link Activity#onStop() Activity.onStop} of the containing 1561 * Activity's lifecycle. 1562 */ 1563 public void onStop() { 1564 mCalled = true; 1565 } 1566 1567 public void onLowMemory() { 1568 mCalled = true; 1569 } 1570 1571 public void onTrimMemory(int level) { 1572 mCalled = true; 1573 } 1574 1575 /** 1576 * Called when the view previously created by {@link #onCreateView} has 1577 * been detached from the fragment. The next time the fragment needs 1578 * to be displayed, a new view will be created. This is called 1579 * after {@link #onStop()} and before {@link #onDestroy()}. It is called 1580 * <em>regardless</em> of whether {@link #onCreateView} returned a 1581 * non-null view. Internally it is called after the view's state has 1582 * been saved but before it has been removed from its parent. 1583 */ 1584 public void onDestroyView() { 1585 mCalled = true; 1586 } 1587 1588 /** 1589 * Called when the fragment is no longer in use. This is called 1590 * after {@link #onStop()} and before {@link #onDetach()}. 1591 */ 1592 public void onDestroy() { 1593 mCalled = true; 1594 //Log.v("foo", "onDestroy: mCheckedForLoaderManager=" + mCheckedForLoaderManager 1595 // + " mLoaderManager=" + mLoaderManager); 1596 if (!mCheckedForLoaderManager) { 1597 mCheckedForLoaderManager = true; 1598 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 1599 } 1600 if (mLoaderManager != null) { 1601 mLoaderManager.doDestroy(); 1602 } 1603 } 1604 1605 /** 1606 * Called by the fragment manager once this fragment has been removed, 1607 * so that we don't have any left-over state if the application decides 1608 * to re-use the instance. This only clears state that the framework 1609 * internally manages, not things the application sets. 1610 */ 1611 void initState() { 1612 mIndex = -1; 1613 mWho = null; 1614 mAdded = false; 1615 mRemoving = false; 1616 mResumed = false; 1617 mFromLayout = false; 1618 mInLayout = false; 1619 mRestored = false; 1620 mBackStackNesting = 0; 1621 mFragmentManager = null; 1622 mChildFragmentManager = null; 1623 mHost = null; 1624 mFragmentId = 0; 1625 mContainerId = 0; 1626 mTag = null; 1627 mHidden = false; 1628 mDetached = false; 1629 mRetaining = false; 1630 mLoaderManager = null; 1631 mLoadersStarted = false; 1632 mCheckedForLoaderManager = false; 1633 } 1634 1635 /** 1636 * Called when the fragment is no longer attached to its activity. This 1637 * is called after {@link #onDestroy()}. 1638 */ 1639 public void onDetach() { 1640 mCalled = true; 1641 } 1642 1643 /** 1644 * Initialize the contents of the Activity's standard options menu. You 1645 * should place your menu items in to <var>menu</var>. For this method 1646 * to be called, you must have first called {@link #setHasOptionsMenu}. See 1647 * {@link Activity#onCreateOptionsMenu(Menu) Activity.onCreateOptionsMenu} 1648 * for more information. 1649 * 1650 * @param menu The options menu in which you place your items. 1651 * 1652 * @see #setHasOptionsMenu 1653 * @see #onPrepareOptionsMenu 1654 * @see #onOptionsItemSelected 1655 */ 1656 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 1657 } 1658 1659 /** 1660 * Prepare the Screen's standard options menu to be displayed. This is 1661 * called right before the menu is shown, every time it is shown. You can 1662 * use this method to efficiently enable/disable items or otherwise 1663 * dynamically modify the contents. See 1664 * {@link Activity#onPrepareOptionsMenu(Menu) Activity.onPrepareOptionsMenu} 1665 * for more information. 1666 * 1667 * @param menu The options menu as last shown or first initialized by 1668 * onCreateOptionsMenu(). 1669 * 1670 * @see #setHasOptionsMenu 1671 * @see #onCreateOptionsMenu 1672 */ 1673 public void onPrepareOptionsMenu(Menu menu) { 1674 } 1675 1676 /** 1677 * Called when this fragment's option menu items are no longer being 1678 * included in the overall options menu. Receiving this call means that 1679 * the menu needed to be rebuilt, but this fragment's items were not 1680 * included in the newly built menu (its {@link #onCreateOptionsMenu(Menu, MenuInflater)} 1681 * was not called). 1682 */ 1683 public void onDestroyOptionsMenu() { 1684 } 1685 1686 /** 1687 * This hook is called whenever an item in your options menu is selected. 1688 * The default implementation simply returns false to have the normal 1689 * processing happen (calling the item's Runnable or sending a message to 1690 * its Handler as appropriate). You can use this method for any items 1691 * for which you would like to do processing without those other 1692 * facilities. 1693 * 1694 * <p>Derived classes should call through to the base class for it to 1695 * perform the default menu handling. 1696 * 1697 * @param item The menu item that was selected. 1698 * 1699 * @return boolean Return false to allow normal menu processing to 1700 * proceed, true to consume it here. 1701 * 1702 * @see #onCreateOptionsMenu 1703 */ 1704 public boolean onOptionsItemSelected(MenuItem item) { 1705 return false; 1706 } 1707 1708 /** 1709 * This hook is called whenever the options menu is being closed (either by the user canceling 1710 * the menu with the back/menu button, or when an item is selected). 1711 * 1712 * @param menu The options menu as last shown or first initialized by 1713 * onCreateOptionsMenu(). 1714 */ 1715 public void onOptionsMenuClosed(Menu menu) { 1716 } 1717 1718 /** 1719 * Called when a context menu for the {@code view} is about to be shown. 1720 * Unlike {@link #onCreateOptionsMenu}, this will be called every 1721 * time the context menu is about to be shown and should be populated for 1722 * the view (or item inside the view for {@link AdapterView} subclasses, 1723 * this can be found in the {@code menuInfo})). 1724 * <p> 1725 * Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an 1726 * item has been selected. 1727 * <p> 1728 * The default implementation calls up to 1729 * {@link Activity#onCreateContextMenu Activity.onCreateContextMenu}, though 1730 * you can not call this implementation if you don't want that behavior. 1731 * <p> 1732 * It is not safe to hold onto the context menu after this method returns. 1733 * {@inheritDoc} 1734 */ 1735 public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { 1736 getActivity().onCreateContextMenu(menu, v, menuInfo); 1737 } 1738 1739 /** 1740 * Registers a context menu to be shown for the given view (multiple views 1741 * can show the context menu). This method will set the 1742 * {@link OnCreateContextMenuListener} on the view to this fragment, so 1743 * {@link #onCreateContextMenu(ContextMenu, View, ContextMenuInfo)} will be 1744 * called when it is time to show the context menu. 1745 * 1746 * @see #unregisterForContextMenu(View) 1747 * @param view The view that should show a context menu. 1748 */ 1749 public void registerForContextMenu(View view) { 1750 view.setOnCreateContextMenuListener(this); 1751 } 1752 1753 /** 1754 * Prevents a context menu to be shown for the given view. This method will 1755 * remove the {@link OnCreateContextMenuListener} on the view. 1756 * 1757 * @see #registerForContextMenu(View) 1758 * @param view The view that should stop showing a context menu. 1759 */ 1760 public void unregisterForContextMenu(View view) { 1761 view.setOnCreateContextMenuListener(null); 1762 } 1763 1764 /** 1765 * This hook is called whenever an item in a context menu is selected. The 1766 * default implementation simply returns false to have the normal processing 1767 * happen (calling the item's Runnable or sending a message to its Handler 1768 * as appropriate). You can use this method for any items for which you 1769 * would like to do processing without those other facilities. 1770 * <p> 1771 * Use {@link MenuItem#getMenuInfo()} to get extra information set by the 1772 * View that added this menu item. 1773 * <p> 1774 * Derived classes should call through to the base class for it to perform 1775 * the default menu handling. 1776 * 1777 * @param item The context menu item that was selected. 1778 * @return boolean Return false to allow normal context menu processing to 1779 * proceed, true to consume it here. 1780 */ 1781 public boolean onContextItemSelected(MenuItem item) { 1782 return false; 1783 } 1784 1785 /** 1786 * When custom transitions are used with Fragments, the enter transition callback 1787 * is called when this Fragment is attached or detached when not popping the back stack. 1788 * 1789 * @param callback Used to manipulate the shared element transitions on this Fragment 1790 * when added not as a pop from the back stack. 1791 */ 1792 public void setEnterSharedElementCallback(SharedElementCallback callback) { 1793 if (callback == null) { 1794 callback = SharedElementCallback.NULL_CALLBACK; 1795 } 1796 mEnterTransitionCallback = callback; 1797 } 1798 1799 /** 1800 * @hide 1801 */ 1802 public void setEnterSharedElementTransitionCallback(SharedElementCallback callback) { 1803 setEnterSharedElementCallback(callback); 1804 } 1805 1806 /** 1807 * When custom transitions are used with Fragments, the exit transition callback 1808 * is called when this Fragment is attached or detached when popping the back stack. 1809 * 1810 * @param callback Used to manipulate the shared element transitions on this Fragment 1811 * when added as a pop from the back stack. 1812 */ 1813 public void setExitSharedElementCallback(SharedElementCallback callback) { 1814 if (callback == null) { 1815 callback = SharedElementCallback.NULL_CALLBACK; 1816 } 1817 mExitTransitionCallback = callback; 1818 } 1819 1820 /** 1821 * @hide 1822 */ 1823 public void setExitSharedElementTransitionCallback(SharedElementCallback callback) { 1824 setExitSharedElementCallback(callback); 1825 } 1826 1827 /** 1828 * Sets the Transition that will be used to move Views into the initial scene. The entering 1829 * Views will be those that are regular Views or ViewGroups that have 1830 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1831 * {@link android.transition.Visibility} as entering is governed by changing visibility from 1832 * {@link View#INVISIBLE} to {@link View#VISIBLE}. If <code>transition</code> is null, 1833 * entering Views will remain unaffected. 1834 * 1835 * @param transition The Transition to use to move Views into the initial Scene. 1836 * @attr ref android.R.styleable#Fragment_fragmentEnterTransition 1837 */ 1838 public void setEnterTransition(Transition transition) { 1839 mEnterTransition = transition; 1840 } 1841 1842 /** 1843 * Returns the Transition that will be used to move Views into the initial scene. The entering 1844 * Views will be those that are regular Views or ViewGroups that have 1845 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1846 * {@link android.transition.Visibility} as entering is governed by changing visibility from 1847 * {@link View#INVISIBLE} to {@link View#VISIBLE}. 1848 * 1849 * @return the Transition to use to move Views into the initial Scene. 1850 * @attr ref android.R.styleable#Fragment_fragmentEnterTransition 1851 */ 1852 public Transition getEnterTransition() { 1853 return mEnterTransition; 1854 } 1855 1856 /** 1857 * Sets the Transition that will be used to move Views out of the scene when the Fragment is 1858 * preparing to be removed, hidden, or detached because of popping the back stack. The exiting 1859 * Views will be those that are regular Views or ViewGroups that have 1860 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1861 * {@link android.transition.Visibility} as entering is governed by changing visibility from 1862 * {@link View#VISIBLE} to {@link View#INVISIBLE}. If <code>transition</code> is null, 1863 * entering Views will remain unaffected. If nothing is set, the default will be to 1864 * use the same value as set in {@link #setEnterTransition(android.transition.Transition)}. 1865 * 1866 * @param transition The Transition to use to move Views out of the Scene when the Fragment 1867 * is preparing to close. 1868 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 1869 */ 1870 public void setReturnTransition(Transition transition) { 1871 mReturnTransition = transition; 1872 } 1873 1874 /** 1875 * Returns the Transition that will be used to move Views out of the scene when the Fragment is 1876 * preparing to be removed, hidden, or detached because of popping the back stack. The exiting 1877 * Views will be those that are regular Views or ViewGroups that have 1878 * {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1879 * {@link android.transition.Visibility} as entering is governed by changing visibility from 1880 * {@link View#VISIBLE} to {@link View#INVISIBLE}. If <code>transition</code> is null, 1881 * entering Views will remain unaffected. 1882 * 1883 * @return the Transition to use to move Views out of the Scene when the Fragment 1884 * is preparing to close. 1885 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 1886 */ 1887 public Transition getReturnTransition() { 1888 return mReturnTransition == USE_DEFAULT_TRANSITION ? getEnterTransition() 1889 : mReturnTransition; 1890 } 1891 1892 /** 1893 * Sets the Transition that will be used to move Views out of the scene when the 1894 * fragment is removed, hidden, or detached when not popping the back stack. 1895 * The exiting Views will be those that are regular Views or ViewGroups that 1896 * have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1897 * {@link android.transition.Visibility} as exiting is governed by changing visibility 1898 * from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, the views will 1899 * remain unaffected. 1900 * 1901 * @param transition The Transition to use to move Views out of the Scene when the Fragment 1902 * is being closed not due to popping the back stack. 1903 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 1904 */ 1905 public void setExitTransition(Transition transition) { 1906 mExitTransition = transition; 1907 } 1908 1909 /** 1910 * Returns the Transition that will be used to move Views out of the scene when the 1911 * fragment is removed, hidden, or detached when not popping the back stack. 1912 * The exiting Views will be those that are regular Views or ViewGroups that 1913 * have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions will extend 1914 * {@link android.transition.Visibility} as exiting is governed by changing visibility 1915 * from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, the views will 1916 * remain unaffected. 1917 * 1918 * @return the Transition to use to move Views out of the Scene when the Fragment 1919 * is being closed not due to popping the back stack. 1920 * @attr ref android.R.styleable#Fragment_fragmentExitTransition 1921 */ 1922 public Transition getExitTransition() { 1923 return mExitTransition; 1924 } 1925 1926 /** 1927 * Sets the Transition that will be used to move Views in to the scene when returning due 1928 * to popping a back stack. The entering Views will be those that are regular Views 1929 * or ViewGroups that have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions 1930 * will extend {@link android.transition.Visibility} as exiting is governed by changing 1931 * visibility from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, 1932 * the views will remain unaffected. If nothing is set, the default will be to use the same 1933 * transition as {@link #setExitTransition(android.transition.Transition)}. 1934 * 1935 * @param transition The Transition to use to move Views into the scene when reentering from a 1936 * previously-started Activity. 1937 * @attr ref android.R.styleable#Fragment_fragmentReenterTransition 1938 */ 1939 public void setReenterTransition(Transition transition) { 1940 mReenterTransition = transition; 1941 } 1942 1943 /** 1944 * Returns the Transition that will be used to move Views in to the scene when returning due 1945 * to popping a back stack. The entering Views will be those that are regular Views 1946 * or ViewGroups that have {@link ViewGroup#isTransitionGroup} return true. Typical Transitions 1947 * will extend {@link android.transition.Visibility} as exiting is governed by changing 1948 * visibility from {@link View#VISIBLE} to {@link View#INVISIBLE}. If transition is null, 1949 * the views will remain unaffected. If nothing is set, the default will be to use the same 1950 * transition as {@link #setExitTransition(android.transition.Transition)}. 1951 * 1952 * @return the Transition to use to move Views into the scene when reentering from a 1953 * previously-started Activity. 1954 * @attr ref android.R.styleable#Fragment_fragmentReenterTransition 1955 */ 1956 public Transition getReenterTransition() { 1957 return mReenterTransition == USE_DEFAULT_TRANSITION ? getExitTransition() 1958 : mReenterTransition; 1959 } 1960 1961 /** 1962 * Sets the Transition that will be used for shared elements transferred into the content 1963 * Scene. Typical Transitions will affect size and location, such as 1964 * {@link android.transition.ChangeBounds}. A null 1965 * value will cause transferred shared elements to blink to the final position. 1966 * 1967 * @param transition The Transition to use for shared elements transferred into the content 1968 * Scene. 1969 * @attr ref android.R.styleable#Fragment_fragmentSharedElementEnterTransition 1970 */ 1971 public void setSharedElementEnterTransition(Transition transition) { 1972 mSharedElementEnterTransition = transition; 1973 } 1974 1975 /** 1976 * Returns the Transition that will be used for shared elements transferred into the content 1977 * Scene. Typical Transitions will affect size and location, such as 1978 * {@link android.transition.ChangeBounds}. A null 1979 * value will cause transferred shared elements to blink to the final position. 1980 * 1981 * @return The Transition to use for shared elements transferred into the content 1982 * Scene. 1983 * @attr ref android.R.styleable#Fragment_fragmentSharedElementEnterTransition 1984 */ 1985 public Transition getSharedElementEnterTransition() { 1986 return mSharedElementEnterTransition; 1987 } 1988 1989 /** 1990 * Sets the Transition that will be used for shared elements transferred back during a 1991 * pop of the back stack. This Transition acts in the leaving Fragment. 1992 * Typical Transitions will affect size and location, such as 1993 * {@link android.transition.ChangeBounds}. A null 1994 * value will cause transferred shared elements to blink to the final position. 1995 * If no value is set, the default will be to use the same value as 1996 * {@link #setSharedElementEnterTransition(android.transition.Transition)}. 1997 * 1998 * @param transition The Transition to use for shared elements transferred out of the content 1999 * Scene. 2000 * @attr ref android.R.styleable#Fragment_fragmentSharedElementReturnTransition 2001 */ 2002 public void setSharedElementReturnTransition(Transition transition) { 2003 mSharedElementReturnTransition = transition; 2004 } 2005 2006 /** 2007 * Return the Transition that will be used for shared elements transferred back during a 2008 * pop of the back stack. This Transition acts in the leaving Fragment. 2009 * Typical Transitions will affect size and location, such as 2010 * {@link android.transition.ChangeBounds}. A null 2011 * value will cause transferred shared elements to blink to the final position. 2012 * If no value is set, the default will be to use the same value as 2013 * {@link #setSharedElementEnterTransition(android.transition.Transition)}. 2014 * 2015 * @return The Transition to use for shared elements transferred out of the content 2016 * Scene. 2017 * @attr ref android.R.styleable#Fragment_fragmentSharedElementReturnTransition 2018 */ 2019 public Transition getSharedElementReturnTransition() { 2020 return mSharedElementReturnTransition == USE_DEFAULT_TRANSITION ? 2021 getSharedElementEnterTransition() : mSharedElementReturnTransition; 2022 } 2023 2024 /** 2025 * Sets whether the the exit transition and enter transition overlap or not. 2026 * When true, the enter transition will start as soon as possible. When false, the 2027 * enter transition will wait until the exit transition completes before starting. 2028 * 2029 * @param allow true to start the enter transition when possible or false to 2030 * wait until the exiting transition completes. 2031 * @attr ref android.R.styleable#Fragment_fragmentAllowEnterTransitionOverlap 2032 */ 2033 public void setAllowEnterTransitionOverlap(boolean allow) { 2034 mAllowEnterTransitionOverlap = allow; 2035 } 2036 2037 /** 2038 * Returns whether the the exit transition and enter transition overlap or not. 2039 * When true, the enter transition will start as soon as possible. When false, the 2040 * enter transition will wait until the exit transition completes before starting. 2041 * 2042 * @return true when the enter transition should start as soon as possible or false to 2043 * when it should wait until the exiting transition completes. 2044 * @attr ref android.R.styleable#Fragment_fragmentAllowEnterTransitionOverlap 2045 */ 2046 public boolean getAllowEnterTransitionOverlap() { 2047 return (mAllowEnterTransitionOverlap == null) ? true : mAllowEnterTransitionOverlap; 2048 } 2049 2050 /** 2051 * Sets whether the the return transition and reenter transition overlap or not. 2052 * When true, the reenter transition will start as soon as possible. When false, the 2053 * reenter transition will wait until the return transition completes before starting. 2054 * 2055 * @param allow true to start the reenter transition when possible or false to wait until the 2056 * return transition completes. 2057 * @attr ref android.R.styleable#Fragment_fragmentAllowReturnTransitionOverlap 2058 */ 2059 public void setAllowReturnTransitionOverlap(boolean allow) { 2060 mAllowReturnTransitionOverlap = allow; 2061 } 2062 2063 /** 2064 * Returns whether the the return transition and reenter transition overlap or not. 2065 * When true, the reenter transition will start as soon as possible. When false, the 2066 * reenter transition will wait until the return transition completes before starting. 2067 * 2068 * @return true to start the reenter transition when possible or false to wait until the 2069 * return transition completes. 2070 * @attr ref android.R.styleable#Fragment_fragmentAllowReturnTransitionOverlap 2071 */ 2072 public boolean getAllowReturnTransitionOverlap() { 2073 return (mAllowReturnTransitionOverlap == null) ? true : mAllowReturnTransitionOverlap; 2074 } 2075 2076 /** 2077 * Print the Fragments's state into the given stream. 2078 * 2079 * @param prefix Text to print at the front of each line. 2080 * @param fd The raw file descriptor that the dump is being sent to. 2081 * @param writer The PrintWriter to which you should dump your state. This will be 2082 * closed for you after you return. 2083 * @param args additional arguments to the dump request. 2084 */ 2085 public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) { 2086 writer.print(prefix); writer.print("mFragmentId=#"); 2087 writer.print(Integer.toHexString(mFragmentId)); 2088 writer.print(" mContainerId=#"); 2089 writer.print(Integer.toHexString(mContainerId)); 2090 writer.print(" mTag="); writer.println(mTag); 2091 writer.print(prefix); writer.print("mState="); writer.print(mState); 2092 writer.print(" mIndex="); writer.print(mIndex); 2093 writer.print(" mWho="); writer.print(mWho); 2094 writer.print(" mBackStackNesting="); writer.println(mBackStackNesting); 2095 writer.print(prefix); writer.print("mAdded="); writer.print(mAdded); 2096 writer.print(" mRemoving="); writer.print(mRemoving); 2097 writer.print(" mResumed="); writer.print(mResumed); 2098 writer.print(" mFromLayout="); writer.print(mFromLayout); 2099 writer.print(" mInLayout="); writer.println(mInLayout); 2100 writer.print(prefix); writer.print("mHidden="); writer.print(mHidden); 2101 writer.print(" mDetached="); writer.print(mDetached); 2102 writer.print(" mMenuVisible="); writer.print(mMenuVisible); 2103 writer.print(" mHasMenu="); writer.println(mHasMenu); 2104 writer.print(prefix); writer.print("mRetainInstance="); writer.print(mRetainInstance); 2105 writer.print(" mRetaining="); writer.print(mRetaining); 2106 writer.print(" mUserVisibleHint="); writer.println(mUserVisibleHint); 2107 if (mFragmentManager != null) { 2108 writer.print(prefix); writer.print("mFragmentManager="); 2109 writer.println(mFragmentManager); 2110 } 2111 if (mHost != null) { 2112 writer.print(prefix); writer.print("mHost="); 2113 writer.println(mHost); 2114 } 2115 if (mParentFragment != null) { 2116 writer.print(prefix); writer.print("mParentFragment="); 2117 writer.println(mParentFragment); 2118 } 2119 if (mArguments != null) { 2120 writer.print(prefix); writer.print("mArguments="); writer.println(mArguments); 2121 } 2122 if (mSavedFragmentState != null) { 2123 writer.print(prefix); writer.print("mSavedFragmentState="); 2124 writer.println(mSavedFragmentState); 2125 } 2126 if (mSavedViewState != null) { 2127 writer.print(prefix); writer.print("mSavedViewState="); 2128 writer.println(mSavedViewState); 2129 } 2130 if (mTarget != null) { 2131 writer.print(prefix); writer.print("mTarget="); writer.print(mTarget); 2132 writer.print(" mTargetRequestCode="); 2133 writer.println(mTargetRequestCode); 2134 } 2135 if (mNextAnim != 0) { 2136 writer.print(prefix); writer.print("mNextAnim="); writer.println(mNextAnim); 2137 } 2138 if (mContainer != null) { 2139 writer.print(prefix); writer.print("mContainer="); writer.println(mContainer); 2140 } 2141 if (mView != null) { 2142 writer.print(prefix); writer.print("mView="); writer.println(mView); 2143 } 2144 if (mAnimatingAway != null) { 2145 writer.print(prefix); writer.print("mAnimatingAway="); writer.println(mAnimatingAway); 2146 writer.print(prefix); writer.print("mStateAfterAnimating="); 2147 writer.println(mStateAfterAnimating); 2148 } 2149 if (mLoaderManager != null) { 2150 writer.print(prefix); writer.println("Loader Manager:"); 2151 mLoaderManager.dump(prefix + " ", fd, writer, args); 2152 } 2153 if (mChildFragmentManager != null) { 2154 writer.print(prefix); writer.println("Child " + mChildFragmentManager + ":"); 2155 mChildFragmentManager.dump(prefix + " ", fd, writer, args); 2156 } 2157 } 2158 2159 Fragment findFragmentByWho(String who) { 2160 if (who.equals(mWho)) { 2161 return this; 2162 } 2163 if (mChildFragmentManager != null) { 2164 return mChildFragmentManager.findFragmentByWho(who); 2165 } 2166 return null; 2167 } 2168 2169 void instantiateChildFragmentManager() { 2170 mChildFragmentManager = new FragmentManagerImpl(); 2171 mChildFragmentManager.attachController(mHost, new FragmentContainer() { 2172 @Override 2173 @Nullable 2174 public View onFindViewById(int id) { 2175 if (mView == null) { 2176 throw new IllegalStateException("Fragment does not have a view"); 2177 } 2178 return mView.findViewById(id); 2179 } 2180 2181 @Override 2182 public boolean onHasView() { 2183 return (mView != null); 2184 } 2185 }, this); 2186 } 2187 2188 void performCreate(Bundle savedInstanceState) { 2189 if (mChildFragmentManager != null) { 2190 mChildFragmentManager.noteStateNotSaved(); 2191 } 2192 mCalled = false; 2193 onCreate(savedInstanceState); 2194 if (!mCalled) { 2195 throw new SuperNotCalledException("Fragment " + this 2196 + " did not call through to super.onCreate()"); 2197 } 2198 if (savedInstanceState != null) { 2199 Parcelable p = savedInstanceState.getParcelable(Activity.FRAGMENTS_TAG); 2200 if (p != null) { 2201 if (mChildFragmentManager == null) { 2202 instantiateChildFragmentManager(); 2203 } 2204 mChildFragmentManager.restoreAllState(p, null); 2205 mChildFragmentManager.dispatchCreate(); 2206 } 2207 } 2208 } 2209 2210 View performCreateView(LayoutInflater inflater, ViewGroup container, 2211 Bundle savedInstanceState) { 2212 if (mChildFragmentManager != null) { 2213 mChildFragmentManager.noteStateNotSaved(); 2214 } 2215 return onCreateView(inflater, container, savedInstanceState); 2216 } 2217 2218 void performActivityCreated(Bundle savedInstanceState) { 2219 if (mChildFragmentManager != null) { 2220 mChildFragmentManager.noteStateNotSaved(); 2221 } 2222 mCalled = false; 2223 onActivityCreated(savedInstanceState); 2224 if (!mCalled) { 2225 throw new SuperNotCalledException("Fragment " + this 2226 + " did not call through to super.onActivityCreated()"); 2227 } 2228 if (mChildFragmentManager != null) { 2229 mChildFragmentManager.dispatchActivityCreated(); 2230 } 2231 } 2232 2233 void performStart() { 2234 if (mChildFragmentManager != null) { 2235 mChildFragmentManager.noteStateNotSaved(); 2236 mChildFragmentManager.execPendingActions(); 2237 } 2238 mCalled = false; 2239 onStart(); 2240 if (!mCalled) { 2241 throw new SuperNotCalledException("Fragment " + this 2242 + " did not call through to super.onStart()"); 2243 } 2244 if (mChildFragmentManager != null) { 2245 mChildFragmentManager.dispatchStart(); 2246 } 2247 if (mLoaderManager != null) { 2248 mLoaderManager.doReportStart(); 2249 } 2250 } 2251 2252 void performResume() { 2253 if (mChildFragmentManager != null) { 2254 mChildFragmentManager.noteStateNotSaved(); 2255 mChildFragmentManager.execPendingActions(); 2256 } 2257 mCalled = false; 2258 onResume(); 2259 if (!mCalled) { 2260 throw new SuperNotCalledException("Fragment " + this 2261 + " did not call through to super.onResume()"); 2262 } 2263 if (mChildFragmentManager != null) { 2264 mChildFragmentManager.dispatchResume(); 2265 mChildFragmentManager.execPendingActions(); 2266 } 2267 } 2268 2269 void performConfigurationChanged(Configuration newConfig) { 2270 onConfigurationChanged(newConfig); 2271 if (mChildFragmentManager != null) { 2272 mChildFragmentManager.dispatchConfigurationChanged(newConfig); 2273 } 2274 } 2275 2276 void performLowMemory() { 2277 onLowMemory(); 2278 if (mChildFragmentManager != null) { 2279 mChildFragmentManager.dispatchLowMemory(); 2280 } 2281 } 2282 2283 void performTrimMemory(int level) { 2284 onTrimMemory(level); 2285 if (mChildFragmentManager != null) { 2286 mChildFragmentManager.dispatchTrimMemory(level); 2287 } 2288 } 2289 2290 boolean performCreateOptionsMenu(Menu menu, MenuInflater inflater) { 2291 boolean show = false; 2292 if (!mHidden) { 2293 if (mHasMenu && mMenuVisible) { 2294 show = true; 2295 onCreateOptionsMenu(menu, inflater); 2296 } 2297 if (mChildFragmentManager != null) { 2298 show |= mChildFragmentManager.dispatchCreateOptionsMenu(menu, inflater); 2299 } 2300 } 2301 return show; 2302 } 2303 2304 boolean performPrepareOptionsMenu(Menu menu) { 2305 boolean show = false; 2306 if (!mHidden) { 2307 if (mHasMenu && mMenuVisible) { 2308 show = true; 2309 onPrepareOptionsMenu(menu); 2310 } 2311 if (mChildFragmentManager != null) { 2312 show |= mChildFragmentManager.dispatchPrepareOptionsMenu(menu); 2313 } 2314 } 2315 return show; 2316 } 2317 2318 boolean performOptionsItemSelected(MenuItem item) { 2319 if (!mHidden) { 2320 if (mHasMenu && mMenuVisible) { 2321 if (onOptionsItemSelected(item)) { 2322 return true; 2323 } 2324 } 2325 if (mChildFragmentManager != null) { 2326 if (mChildFragmentManager.dispatchOptionsItemSelected(item)) { 2327 return true; 2328 } 2329 } 2330 } 2331 return false; 2332 } 2333 2334 boolean performContextItemSelected(MenuItem item) { 2335 if (!mHidden) { 2336 if (onContextItemSelected(item)) { 2337 return true; 2338 } 2339 if (mChildFragmentManager != null) { 2340 if (mChildFragmentManager.dispatchContextItemSelected(item)) { 2341 return true; 2342 } 2343 } 2344 } 2345 return false; 2346 } 2347 2348 void performOptionsMenuClosed(Menu menu) { 2349 if (!mHidden) { 2350 if (mHasMenu && mMenuVisible) { 2351 onOptionsMenuClosed(menu); 2352 } 2353 if (mChildFragmentManager != null) { 2354 mChildFragmentManager.dispatchOptionsMenuClosed(menu); 2355 } 2356 } 2357 } 2358 2359 void performSaveInstanceState(Bundle outState) { 2360 onSaveInstanceState(outState); 2361 if (mChildFragmentManager != null) { 2362 Parcelable p = mChildFragmentManager.saveAllState(); 2363 if (p != null) { 2364 outState.putParcelable(Activity.FRAGMENTS_TAG, p); 2365 } 2366 } 2367 } 2368 2369 void performPause() { 2370 if (mChildFragmentManager != null) { 2371 mChildFragmentManager.dispatchPause(); 2372 } 2373 mCalled = false; 2374 onPause(); 2375 if (!mCalled) { 2376 throw new SuperNotCalledException("Fragment " + this 2377 + " did not call through to super.onPause()"); 2378 } 2379 } 2380 2381 void performStop() { 2382 if (mChildFragmentManager != null) { 2383 mChildFragmentManager.dispatchStop(); 2384 } 2385 mCalled = false; 2386 onStop(); 2387 if (!mCalled) { 2388 throw new SuperNotCalledException("Fragment " + this 2389 + " did not call through to super.onStop()"); 2390 } 2391 2392 if (mLoadersStarted) { 2393 mLoadersStarted = false; 2394 if (!mCheckedForLoaderManager) { 2395 mCheckedForLoaderManager = true; 2396 mLoaderManager = mHost.getLoaderManager(mWho, mLoadersStarted, false); 2397 } 2398 if (mLoaderManager != null) { 2399 if (mRetaining) { 2400 mLoaderManager.doRetain(); 2401 } else { 2402 mLoaderManager.doStop(); 2403 } 2404 } 2405 } 2406 } 2407 2408 void performDestroyView() { 2409 if (mChildFragmentManager != null) { 2410 mChildFragmentManager.dispatchDestroyView(); 2411 } 2412 mCalled = false; 2413 onDestroyView(); 2414 if (!mCalled) { 2415 throw new SuperNotCalledException("Fragment " + this 2416 + " did not call through to super.onDestroyView()"); 2417 } 2418 if (mLoaderManager != null) { 2419 mLoaderManager.doReportNextStart(); 2420 } 2421 } 2422 2423 void performDestroy() { 2424 if (mChildFragmentManager != null) { 2425 mChildFragmentManager.dispatchDestroy(); 2426 } 2427 mCalled = false; 2428 onDestroy(); 2429 if (!mCalled) { 2430 throw new SuperNotCalledException("Fragment " + this 2431 + " did not call through to super.onDestroy()"); 2432 } 2433 } 2434 2435 private static Transition loadTransition(Context context, TypedArray typedArray, 2436 Transition currentValue, Transition defaultValue, int id) { 2437 if (currentValue != defaultValue) { 2438 return currentValue; 2439 } 2440 int transitionId = typedArray.getResourceId(id, 0); 2441 Transition transition = defaultValue; 2442 if (transitionId != 0 && transitionId != com.android.internal.R.transition.no_transition) { 2443 TransitionInflater inflater = TransitionInflater.from(context); 2444 transition = inflater.inflateTransition(transitionId); 2445 if (transition instanceof TransitionSet && 2446 ((TransitionSet)transition).getTransitionCount() == 0) { 2447 transition = null; 2448 } 2449 } 2450 return transition; 2451 } 2452 2453} 2454