Fragment.java revision 3790001c20494d1f355a67bec7751c4b8f07874f
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.content.ComponentCallbacks2; 21import android.content.Context; 22import android.content.Intent; 23import android.content.res.Configuration; 24import android.content.res.Resources; 25import android.os.Bundle; 26import android.os.Parcel; 27import android.os.Parcelable; 28import android.util.AndroidRuntimeException; 29import android.util.AttributeSet; 30import android.util.DebugUtils; 31import android.util.SparseArray; 32import android.view.ContextMenu; 33import android.view.ContextMenu.ContextMenuInfo; 34import android.view.LayoutInflater; 35import android.view.Menu; 36import android.view.MenuInflater; 37import android.view.MenuItem; 38import android.view.View; 39import android.view.View.OnCreateContextMenuListener; 40import android.view.ViewGroup; 41import android.widget.AdapterView; 42 43import java.io.FileDescriptor; 44import java.io.PrintWriter; 45import java.util.HashMap; 46 47final class FragmentState implements Parcelable { 48 final String mClassName; 49 final int mIndex; 50 final boolean mFromLayout; 51 final int mFragmentId; 52 final int mContainerId; 53 final String mTag; 54 final boolean mRetainInstance; 55 final boolean mDetached; 56 final Bundle mArguments; 57 58 Bundle mSavedFragmentState; 59 60 Fragment mInstance; 61 62 public FragmentState(Fragment frag) { 63 mClassName = frag.getClass().getName(); 64 mIndex = frag.mIndex; 65 mFromLayout = frag.mFromLayout; 66 mFragmentId = frag.mFragmentId; 67 mContainerId = frag.mContainerId; 68 mTag = frag.mTag; 69 mRetainInstance = frag.mRetainInstance; 70 mDetached = frag.mDetached; 71 mArguments = frag.mArguments; 72 } 73 74 public FragmentState(Parcel in) { 75 mClassName = in.readString(); 76 mIndex = in.readInt(); 77 mFromLayout = in.readInt() != 0; 78 mFragmentId = in.readInt(); 79 mContainerId = in.readInt(); 80 mTag = in.readString(); 81 mRetainInstance = in.readInt() != 0; 82 mDetached = in.readInt() != 0; 83 mArguments = in.readBundle(); 84 mSavedFragmentState = in.readBundle(); 85 } 86 87 public Fragment instantiate(Activity activity) { 88 if (mInstance != null) { 89 return mInstance; 90 } 91 92 if (mArguments != null) { 93 mArguments.setClassLoader(activity.getClassLoader()); 94 } 95 96 mInstance = Fragment.instantiate(activity, mClassName, mArguments); 97 98 if (mSavedFragmentState != null) { 99 mSavedFragmentState.setClassLoader(activity.getClassLoader()); 100 mInstance.mSavedFragmentState = mSavedFragmentState; 101 } 102 mInstance.setIndex(mIndex); 103 mInstance.mFromLayout = mFromLayout; 104 mInstance.mRestored = true; 105 mInstance.mFragmentId = mFragmentId; 106 mInstance.mContainerId = mContainerId; 107 mInstance.mTag = mTag; 108 mInstance.mRetainInstance = mRetainInstance; 109 mInstance.mDetached = mDetached; 110 mInstance.mFragmentManager = activity.mFragments; 111 112 return mInstance; 113 } 114 115 public int describeContents() { 116 return 0; 117 } 118 119 public void writeToParcel(Parcel dest, int flags) { 120 dest.writeString(mClassName); 121 dest.writeInt(mIndex); 122 dest.writeInt(mFromLayout ? 1 : 0); 123 dest.writeInt(mFragmentId); 124 dest.writeInt(mContainerId); 125 dest.writeString(mTag); 126 dest.writeInt(mRetainInstance ? 1 : 0); 127 dest.writeInt(mDetached ? 1 : 0); 128 dest.writeBundle(mArguments); 129 dest.writeBundle(mSavedFragmentState); 130 } 131 132 public static final Parcelable.Creator<FragmentState> CREATOR 133 = new Parcelable.Creator<FragmentState>() { 134 public FragmentState createFromParcel(Parcel in) { 135 return new FragmentState(in); 136 } 137 138 public FragmentState[] newArray(int size) { 139 return new FragmentState[size]; 140 } 141 }; 142} 143 144/** 145 * A Fragment is a piece of an application's user interface or behavior 146 * that can be placed in an {@link Activity}. Interaction with fragments 147 * is done through {@link FragmentManager}, which can be obtained via 148 * {@link Activity#getFragmentManager() Activity.getFragmentManager()} and 149 * {@link Fragment#getFragmentManager() Fragment.getFragmentManager()}. 150 * 151 * <p>The Fragment class can be used many ways to achieve a wide variety of 152 * results. In its core, it represents a particular operation or interface 153 * that is running within a larger {@link Activity}. A Fragment is closely 154 * tied to the Activity it is in, and can not be used apart from one. Though 155 * Fragment defines its own lifecycle, that lifecycle is dependent on its 156 * activity: if the activity is stopped, no fragments inside of it can be 157 * started; when the activity is destroyed, all fragments will be destroyed. 158 * 159 * <p>All subclasses of Fragment must include a public empty constructor. 160 * The framework will often re-instantiate a fragment class when needed, 161 * in particular during state restore, and needs to be able to find this 162 * constructor to instantiate it. If the empty constructor is not available, 163 * a runtime exception will occur in some cases during state restore. 164 * 165 * <p>Topics covered here: 166 * <ol> 167 * <li><a href="#OlderPlatforms">Older Platforms</a> 168 * <li><a href="#Lifecycle">Lifecycle</a> 169 * <li><a href="#Layout">Layout</a> 170 * <li><a href="#BackStack">Back Stack</a> 171 * </ol> 172 * 173 * <div class="special reference"> 174 * <h3>Developer Guides</h3> 175 * <p>For more information about using fragments, read the 176 * <a href="{@docRoot}guide/topics/fundamentals/fragments.html">Fragments</a> developer guide.</p> 177 * </div> 178 * 179 * <a name="OlderPlatforms"></a> 180 * <h3>Older Platforms</h3> 181 * 182 * While the Fragment API was introduced in 183 * {@link android.os.Build.VERSION_CODES#HONEYCOMB}, a version of the API 184 * at is also available for use on older platforms through 185 * {@link android.support.v4.app.FragmentActivity}. See the blog post 186 * <a href="http://android-developers.blogspot.com/2011/03/fragments-for-all.html"> 187 * Fragments For All</a> for more details. 188 * 189 * <a name="Lifecycle"></a> 190 * <h3>Lifecycle</h3> 191 * 192 * <p>Though a Fragment's lifecycle is tied to its owning activity, it has 193 * its own wrinkle on the standard activity lifecycle. It includes basic 194 * activity lifecycle methods such as {@link #onResume}, but also important 195 * are methods related to interactions with the activity and UI generation. 196 * 197 * <p>The core series of lifecycle methods that are called to bring a fragment 198 * up to resumed state (interacting with the user) are: 199 * 200 * <ol> 201 * <li> {@link #onAttach} called once the fragment is associated with its activity. 202 * <li> {@link #onCreate} called to do initial creation of the fragment. 203 * <li> {@link #onCreateView} creates and returns the view hierarchy associated 204 * with the fragment. 205 * <li> {@link #onActivityCreated} tells the fragment that its activity has 206 * completed its own {@link Activity#onCreate Activity.onCreate()}. 207 * <li> {@link #onStart} makes the fragment visible to the user (based on its 208 * containing activity being started). 209 * <li> {@link #onResume} makes the fragment interacting with the user (based on its 210 * containing activity being resumed). 211 * </ol> 212 * 213 * <p>As a fragment is no longer being used, it goes through a reverse 214 * series of callbacks: 215 * 216 * <ol> 217 * <li> {@link #onPause} fragment is no longer interacting with the user either 218 * because its activity is being paused or a fragment operation is modifying it 219 * in the activity. 220 * <li> {@link #onStop} fragment is no longer visible to the user either 221 * because its activity is being stopped or a fragment operation is modifying it 222 * in the activity. 223 * <li> {@link #onDestroyView} allows the fragment to clean up resources 224 * associated with its View. 225 * <li> {@link #onDestroy} called to do final cleanup of the fragment's state. 226 * <li> {@link #onDetach} called immediately prior to the fragment no longer 227 * being associated with its activity. 228 * </ol> 229 * 230 * <a name="Layout"></a> 231 * <h3>Layout</h3> 232 * 233 * <p>Fragments can be used as part of your application's layout, allowing 234 * you to better modularize your code and more easily adjust your user 235 * interface to the screen it is running on. As an example, we can look 236 * at a simple program consisting of a list of items, and display of the 237 * details of each item.</p> 238 * 239 * <p>An activity's layout XML can include <code><fragment></code> tags 240 * to embed fragment instances inside of the layout. For example, here is 241 * a simple layout that embeds one fragment:</p> 242 * 243 * {@sample development/samples/ApiDemos/res/layout/fragment_layout.xml layout} 244 * 245 * <p>The layout is installed in the activity in the normal way:</p> 246 * 247 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 248 * main} 249 * 250 * <p>The titles fragment, showing a list of titles, is fairly simple, relying 251 * on {@link ListFragment} for most of its work. Note the implementation of 252 * clicking an item: depending on the current activity's layout, it can either 253 * create and display a new fragment to show the details in-place (more about 254 * this later), or start a new activity to show the details.</p> 255 * 256 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 257 * titles} 258 * 259 * <p>The details fragment showing the contents of a selected item just 260 * displays a string of text based on an index of a string array built in to 261 * the app:</p> 262 * 263 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 264 * details} 265 * 266 * <p>In this case when the user clicks on a title, there is no details 267 * container in the current activity, so the titles fragment's click code will 268 * launch a new activity to display the details fragment:</p> 269 * 270 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentLayout.java 271 * details_activity} 272 * 273 * <p>However the screen may be large enough to show both the list of titles 274 * and details about the currently selected title. To use such a layout on 275 * a landscape screen, this alternative layout can be placed under layout-land:</p> 276 * 277 * {@sample development/samples/ApiDemos/res/layout-land/fragment_layout.xml layout} 278 * 279 * <p>Note how the prior code will adjust to this alternative UI flow: the titles 280 * fragment will now embed the details fragment inside of this activity, and the 281 * details activity will finish itself if it is running in a configuration 282 * where the details can be shown in-place. 283 * 284 * <p>When a configuration change causes the activity hosting these fragments 285 * to restart, its new instance may use a different layout that doesn't 286 * include the same fragments as the previous layout. In this case all of 287 * the previous fragments will still be instantiated and running in the new 288 * instance. However, any that are no longer associated with a <fragment> 289 * tag in the view hierarchy will not have their content view created 290 * and will return false from {@link #isInLayout}. (The code here also shows 291 * how you can determine if a fragment placed in a container is no longer 292 * running in a layout with that container and avoid creating its view hierarchy 293 * in that case.) 294 * 295 * <p>The attributes of the <fragment> tag are used to control the 296 * LayoutParams provided when attaching the fragment's view to the parent 297 * container. They can also be parsed by the fragment in {@link #onInflate} 298 * as parameters. 299 * 300 * <p>The fragment being instantiated must have some kind of unique identifier 301 * so that it can be re-associated with a previous instance if the parent 302 * activity needs to be destroyed and recreated. This can be provided these 303 * ways: 304 * 305 * <ul> 306 * <li>If nothing is explicitly supplied, the view ID of the container will 307 * be used. 308 * <li><code>android:tag</code> can be used in <fragment> to provide 309 * a specific tag name for the fragment. 310 * <li><code>android:id</code> can be used in <fragment> to provide 311 * a specific identifier for the fragment. 312 * </ul> 313 * 314 * <a name="BackStack"></a> 315 * <h3>Back Stack</h3> 316 * 317 * <p>The transaction in which fragments are modified can be placed on an 318 * internal back-stack of the owning activity. When the user presses back 319 * in the activity, any transactions on the back stack are popped off before 320 * the activity itself is finished. 321 * 322 * <p>For example, consider this simple fragment that is instantiated with 323 * an integer argument and displays that in a TextView in its UI:</p> 324 * 325 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 326 * fragment} 327 * 328 * <p>A function that creates a new instance of the fragment, replacing 329 * whatever current fragment instance is being shown and pushing that change 330 * on to the back stack could be written as: 331 * 332 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentStack.java 333 * add_stack} 334 * 335 * <p>After each call to this function, a new entry is on the stack, and 336 * pressing back will pop it to return the user to whatever previous state 337 * the activity UI was in. 338 */ 339public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListener { 340 private static final HashMap<String, Class<?>> sClassMap = 341 new HashMap<String, Class<?>>(); 342 343 static final int INVALID_STATE = -1; // Invalid state used as a null value. 344 static final int INITIALIZING = 0; // Not yet created. 345 static final int CREATED = 1; // Created. 346 static final int ACTIVITY_CREATED = 2; // The activity has finished its creation. 347 static final int STOPPED = 3; // Fully created, not started. 348 static final int STARTED = 4; // Created and started, not resumed. 349 static final int RESUMED = 5; // Created started and resumed. 350 351 int mState = INITIALIZING; 352 353 // Non-null if the fragment's view hierarchy is currently animating away, 354 // meaning we need to wait a bit on completely destroying it. This is the 355 // animation that is running. 356 Animator mAnimatingAway; 357 358 // If mAnimatingAway != null, this is the state we should move to once the 359 // animation is done. 360 int mStateAfterAnimating; 361 362 // When instantiated from saved state, this is the saved state. 363 Bundle mSavedFragmentState; 364 SparseArray<Parcelable> mSavedViewState; 365 366 // Index into active fragment array. 367 int mIndex = -1; 368 369 // Internal unique name for this fragment; 370 String mWho; 371 372 // Construction arguments; 373 Bundle mArguments; 374 375 // Target fragment. 376 Fragment mTarget; 377 378 // For use when retaining a fragment: this is the index of the last mTarget. 379 int mTargetIndex = -1; 380 381 // Target request code. 382 int mTargetRequestCode; 383 384 // True if the fragment is in the list of added fragments. 385 boolean mAdded; 386 387 // If set this fragment is being removed from its activity. 388 boolean mRemoving; 389 390 // True if the fragment is in the resumed state. 391 boolean mResumed; 392 393 // Set to true if this fragment was instantiated from a layout file. 394 boolean mFromLayout; 395 396 // Set to true when the view has actually been inflated in its layout. 397 boolean mInLayout; 398 399 // True if this fragment has been restored from previously saved state. 400 boolean mRestored; 401 402 // Number of active back stack entries this fragment is in. 403 int mBackStackNesting; 404 405 // The fragment manager we are associated with. Set as soon as the 406 // fragment is used in a transaction; cleared after it has been removed 407 // from all transactions. 408 FragmentManagerImpl mFragmentManager; 409 410 // Activity this fragment is attached to. 411 Activity mActivity; 412 413 // The optional identifier for this fragment -- either the container ID if it 414 // was dynamically added to the view hierarchy, or the ID supplied in 415 // layout. 416 int mFragmentId; 417 418 // When a fragment is being dynamically added to the view hierarchy, this 419 // is the identifier of the parent container it is being added to. 420 int mContainerId; 421 422 // The optional named tag for this fragment -- usually used to find 423 // fragments that are not part of the layout. 424 String mTag; 425 426 // Set to true when the app has requested that this fragment be hidden 427 // from the user. 428 boolean mHidden; 429 430 // Set to true when the app has requested that this fragment be detached. 431 boolean mDetached; 432 433 // If set this fragment would like its instance retained across 434 // configuration changes. 435 boolean mRetainInstance; 436 437 // If set this fragment is being retained across the current config change. 438 boolean mRetaining; 439 440 // If set this fragment has menu items to contribute. 441 boolean mHasMenu; 442 443 // Set to true to allow the fragment's menu to be shown. 444 boolean mMenuVisible = true; 445 446 // Used to verify that subclasses call through to super class. 447 boolean mCalled; 448 449 // If app has requested a specific animation, this is the one to use. 450 int mNextAnim; 451 452 // The parent container of the fragment after dynamically added to UI. 453 ViewGroup mContainer; 454 455 // The View generated for this fragment. 456 View mView; 457 458 // Whether this fragment should defer starting until after other fragments 459 // have been started and their loaders are finished. 460 boolean mDeferStart; 461 462 // Hint provided by the app that this fragment is currently visible to the user. 463 boolean mUserVisibleHint = true; 464 465 LoaderManagerImpl mLoaderManager; 466 boolean mLoadersStarted; 467 boolean mCheckedForLoaderManager; 468 469 /** 470 * State information that has been retrieved from a fragment instance 471 * through {@link FragmentManager#saveFragmentInstanceState(Fragment) 472 * FragmentManager.saveFragmentInstanceState}. 473 */ 474 public static class SavedState implements Parcelable { 475 final Bundle mState; 476 477 SavedState(Bundle state) { 478 mState = state; 479 } 480 481 SavedState(Parcel in, ClassLoader loader) { 482 mState = in.readBundle(); 483 if (loader != null && mState != null) { 484 mState.setClassLoader(loader); 485 } 486 } 487 488 @Override 489 public int describeContents() { 490 return 0; 491 } 492 493 @Override 494 public void writeToParcel(Parcel dest, int flags) { 495 dest.writeBundle(mState); 496 } 497 498 public static final Parcelable.ClassLoaderCreator<SavedState> CREATOR 499 = new Parcelable.ClassLoaderCreator<SavedState>() { 500 public SavedState createFromParcel(Parcel in) { 501 return new SavedState(in, null); 502 } 503 504 public SavedState createFromParcel(Parcel in, ClassLoader loader) { 505 return new SavedState(in, loader); 506 } 507 508 public SavedState[] newArray(int size) { 509 return new SavedState[size]; 510 } 511 }; 512 } 513 514 /** 515 * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when 516 * there is an instantiation failure. 517 */ 518 static public class InstantiationException extends AndroidRuntimeException { 519 public InstantiationException(String msg, Exception cause) { 520 super(msg, cause); 521 } 522 } 523 524 /** 525 * Default constructor. <strong>Every</strong> fragment must have an 526 * empty constructor, so it can be instantiated when restoring its 527 * activity's state. It is strongly recommended that subclasses do not 528 * have other constructors with parameters, since these constructors 529 * will not be called when the fragment is re-instantiated; instead, 530 * arguments can be supplied by the caller with {@link #setArguments} 531 * and later retrieved by the Fragment with {@link #getArguments}. 532 * 533 * <p>Applications should generally not implement a constructor. The 534 * first place application code an run where the fragment is ready to 535 * be used is in {@link #onAttach(Activity)}, the point where the fragment 536 * is actually associated with its activity. Some applications may also 537 * want to implement {@link #onInflate} to retrieve attributes from a 538 * layout resource, though should take care here because this happens for 539 * the fragment is attached to its activity. 540 */ 541 public Fragment() { 542 } 543 544 /** 545 * Like {@link #instantiate(Context, String, Bundle)} but with a null 546 * argument Bundle. 547 */ 548 public static Fragment instantiate(Context context, String fname) { 549 return instantiate(context, fname, null); 550 } 551 552 /** 553 * Create a new instance of a Fragment with the given class name. This is 554 * the same as calling its empty constructor. 555 * 556 * @param context The calling context being used to instantiate the fragment. 557 * This is currently just used to get its ClassLoader. 558 * @param fname The class name of the fragment to instantiate. 559 * @param args Bundle of arguments to supply to the fragment, which it 560 * can retrieve with {@link #getArguments()}. May be null. 561 * @return Returns a new fragment instance. 562 * @throws InstantiationException If there is a failure in instantiating 563 * the given fragment class. This is a runtime exception; it is not 564 * normally expected to happen. 565 */ 566 public static Fragment instantiate(Context context, String fname, Bundle args) { 567 try { 568 Class<?> clazz = sClassMap.get(fname); 569 if (clazz == null) { 570 // Class not found in the cache, see if it's real, and try to add it 571 clazz = context.getClassLoader().loadClass(fname); 572 sClassMap.put(fname, clazz); 573 } 574 Fragment f = (Fragment)clazz.newInstance(); 575 if (args != null) { 576 args.setClassLoader(f.getClass().getClassLoader()); 577 f.mArguments = args; 578 } 579 return f; 580 } catch (ClassNotFoundException e) { 581 throw new InstantiationException("Unable to instantiate fragment " + fname 582 + ": make sure class name exists, is public, and has an" 583 + " empty constructor that is public", e); 584 } catch (java.lang.InstantiationException e) { 585 throw new InstantiationException("Unable to instantiate fragment " + fname 586 + ": make sure class name exists, is public, and has an" 587 + " empty constructor that is public", e); 588 } catch (IllegalAccessException e) { 589 throw new InstantiationException("Unable to instantiate fragment " + fname 590 + ": make sure class name exists, is public, and has an" 591 + " empty constructor that is public", e); 592 } 593 } 594 595 final void restoreViewState() { 596 if (mSavedViewState != null) { 597 mView.restoreHierarchyState(mSavedViewState); 598 mSavedViewState = null; 599 } 600 } 601 602 final void setIndex(int index) { 603 mIndex = index; 604 mWho = "android:fragment:" + mIndex; 605 } 606 607 final boolean isInBackStack() { 608 return mBackStackNesting > 0; 609 } 610 611 /** 612 * Subclasses can not override equals(). 613 */ 614 @Override final public boolean equals(Object o) { 615 return super.equals(o); 616 } 617 618 /** 619 * Subclasses can not override hashCode(). 620 */ 621 @Override final public int hashCode() { 622 return super.hashCode(); 623 } 624 625 @Override 626 public String toString() { 627 StringBuilder sb = new StringBuilder(128); 628 DebugUtils.buildShortClassTag(this, sb); 629 if (mIndex >= 0) { 630 sb.append(" #"); 631 sb.append(mIndex); 632 } 633 if (mFragmentId != 0) { 634 sb.append(" id=0x"); 635 sb.append(Integer.toHexString(mFragmentId)); 636 } 637 if (mTag != null) { 638 sb.append(" "); 639 sb.append(mTag); 640 } 641 sb.append('}'); 642 return sb.toString(); 643 } 644 645 /** 646 * Return the identifier this fragment is known by. This is either 647 * the android:id value supplied in a layout or the container view ID 648 * supplied when adding the fragment. 649 */ 650 final public int getId() { 651 return mFragmentId; 652 } 653 654 /** 655 * Get the tag name of the fragment, if specified. 656 */ 657 final public String getTag() { 658 return mTag; 659 } 660 661 /** 662 * Supply the construction arguments for this fragment. This can only 663 * be called before the fragment has been attached to its activity; that 664 * is, you should call it immediately after constructing the fragment. The 665 * arguments supplied here will be retained across fragment destroy and 666 * creation. 667 */ 668 public void setArguments(Bundle args) { 669 if (mIndex >= 0) { 670 throw new IllegalStateException("Fragment already active"); 671 } 672 mArguments = args; 673 } 674 675 /** 676 * Return the arguments supplied when the fragment was instantiated, 677 * if any. 678 */ 679 final public Bundle getArguments() { 680 return mArguments; 681 } 682 683 /** 684 * Set the initial saved state that this Fragment should restore itself 685 * from when first being constructed, as returned by 686 * {@link FragmentManager#saveFragmentInstanceState(Fragment) 687 * FragmentManager.saveFragmentInstanceState}. 688 * 689 * @param state The state the fragment should be restored from. 690 */ 691 public void setInitialSavedState(SavedState state) { 692 if (mIndex >= 0) { 693 throw new IllegalStateException("Fragment already active"); 694 } 695 mSavedFragmentState = state != null && state.mState != null 696 ? state.mState : null; 697 } 698 699 /** 700 * Optional target for this fragment. This may be used, for example, 701 * if this fragment is being started by another, and when done wants to 702 * give a result back to the first. The target set here is retained 703 * across instances via {@link FragmentManager#putFragment 704 * FragmentManager.putFragment()}. 705 * 706 * @param fragment The fragment that is the target of this one. 707 * @param requestCode Optional request code, for convenience if you 708 * are going to call back with {@link #onActivityResult(int, int, Intent)}. 709 */ 710 public void setTargetFragment(Fragment fragment, int requestCode) { 711 mTarget = fragment; 712 mTargetRequestCode = requestCode; 713 } 714 715 /** 716 * Return the target fragment set by {@link #setTargetFragment}. 717 */ 718 final public Fragment getTargetFragment() { 719 return mTarget; 720 } 721 722 /** 723 * Return the target request code set by {@link #setTargetFragment}. 724 */ 725 final public int getTargetRequestCode() { 726 return mTargetRequestCode; 727 } 728 729 /** 730 * Return the Activity this fragment is currently associated with. 731 */ 732 final public Activity getActivity() { 733 return mActivity; 734 } 735 736 /** 737 * Return <code>getActivity().getResources()</code>. 738 */ 739 final public Resources getResources() { 740 if (mActivity == null) { 741 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 742 } 743 return mActivity.getResources(); 744 } 745 746 /** 747 * Return a localized, styled CharSequence from the application's package's 748 * default string table. 749 * 750 * @param resId Resource id for the CharSequence text 751 */ 752 public final CharSequence getText(int resId) { 753 return getResources().getText(resId); 754 } 755 756 /** 757 * Return a localized string from the application's package's 758 * default string table. 759 * 760 * @param resId Resource id for the string 761 */ 762 public final String getString(int resId) { 763 return getResources().getString(resId); 764 } 765 766 /** 767 * Return a localized formatted string from the application's package's 768 * default string table, substituting the format arguments as defined in 769 * {@link java.util.Formatter} and {@link java.lang.String#format}. 770 * 771 * @param resId Resource id for the format string 772 * @param formatArgs The format arguments that will be used for substitution. 773 */ 774 775 public final String getString(int resId, Object... formatArgs) { 776 return getResources().getString(resId, formatArgs); 777 } 778 779 /** 780 * Return the FragmentManager for interacting with fragments associated 781 * with this fragment's activity. Note that this will be non-null slightly 782 * before {@link #getActivity()}, during the time from when the fragment is 783 * placed in a {@link FragmentTransaction} until it is committed and 784 * attached to its activity. 785 */ 786 final public FragmentManager getFragmentManager() { 787 return mFragmentManager; 788 } 789 790 /** 791 * Return true if the fragment is currently added to its activity. 792 */ 793 final public boolean isAdded() { 794 return mActivity != null && mAdded; 795 } 796 797 /** 798 * Return true if the fragment has been explicitly detached from the UI. 799 * That is, {@link FragmentTransaction#detach(Fragment) 800 * FragmentTransaction.detach(Fragment)} has been used on it. 801 */ 802 final public boolean isDetached() { 803 return mDetached; 804 } 805 806 /** 807 * Return true if this fragment is currently being removed from its 808 * activity. This is <em>not</em> whether its activity is finishing, but 809 * rather whether it is in the process of being removed from its activity. 810 */ 811 final public boolean isRemoving() { 812 return mRemoving; 813 } 814 815 /** 816 * Return true if the layout is included as part of an activity view 817 * hierarchy via the <fragment> tag. This will always be true when 818 * fragments are created through the <fragment> tag, <em>except</em> 819 * in the case where an old fragment is restored from a previous state and 820 * it does not appear in the layout of the current state. 821 */ 822 final public boolean isInLayout() { 823 return mInLayout; 824 } 825 826 /** 827 * Return true if the fragment is in the resumed state. This is true 828 * for the duration of {@link #onResume()} and {@link #onPause()} as well. 829 */ 830 final public boolean isResumed() { 831 return mResumed; 832 } 833 834 /** 835 * Return true if the fragment is currently visible to the user. This means 836 * it: (1) has been added, (2) has its view attached to the window, and 837 * (3) is not hidden. 838 */ 839 final public boolean isVisible() { 840 return isAdded() && !isHidden() && mView != null 841 && mView.getWindowToken() != null && mView.getVisibility() == View.VISIBLE; 842 } 843 844 /** 845 * Return true if the fragment has been hidden. By default fragments 846 * are shown. You can find out about changes to this state with 847 * {@link #onHiddenChanged}. Note that the hidden state is orthogonal 848 * to other states -- that is, to be visible to the user, a fragment 849 * must be both started and not hidden. 850 */ 851 final public boolean isHidden() { 852 return mHidden; 853 } 854 855 /** 856 * Called when the hidden state (as returned by {@link #isHidden()} of 857 * the fragment has changed. Fragments start out not hidden; this will 858 * be called whenever the fragment changes state from that. 859 * @param hidden True if the fragment is now hidden, false if it is not 860 * visible. 861 */ 862 public void onHiddenChanged(boolean hidden) { 863 } 864 865 /** 866 * Control whether a fragment instance is retained across Activity 867 * re-creation (such as from a configuration change). This can only 868 * be used with fragments not in the back stack. If set, the fragment 869 * lifecycle will be slightly different when an activity is recreated: 870 * <ul> 871 * <li> {@link #onDestroy()} will not be called (but {@link #onDetach()} still 872 * will be, because the fragment is being detached from its current activity). 873 * <li> {@link #onCreate(Bundle)} will not be called since the fragment 874 * is not being re-created. 875 * <li> {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} <b>will</b> 876 * still be called. 877 * </ul> 878 */ 879 public void setRetainInstance(boolean retain) { 880 mRetainInstance = retain; 881 } 882 883 final public boolean getRetainInstance() { 884 return mRetainInstance; 885 } 886 887 /** 888 * Report that this fragment would like to participate in populating 889 * the options menu by receiving a call to {@link #onCreateOptionsMenu} 890 * and related methods. 891 * 892 * @param hasMenu If true, the fragment has menu items to contribute. 893 */ 894 public void setHasOptionsMenu(boolean hasMenu) { 895 if (mHasMenu != hasMenu) { 896 mHasMenu = hasMenu; 897 if (isAdded() && !isHidden()) { 898 mFragmentManager.invalidateOptionsMenu(); 899 } 900 } 901 } 902 903 /** 904 * Set a hint for whether this fragment's menu should be visible. This 905 * is useful if you know that a fragment has been placed in your view 906 * hierarchy so that the user can not currently seen it, so any menu items 907 * it has should also not be shown. 908 * 909 * @param menuVisible The default is true, meaning the fragment's menu will 910 * be shown as usual. If false, the user will not see the menu. 911 */ 912 public void setMenuVisibility(boolean menuVisible) { 913 if (mMenuVisible != menuVisible) { 914 mMenuVisible = menuVisible; 915 if (mHasMenu && isAdded() && !isHidden()) { 916 mFragmentManager.invalidateOptionsMenu(); 917 } 918 } 919 } 920 921 /** 922 * Set a hint to the system about whether this fragment's UI is currently visible 923 * to the user. This hint defaults to true and is persistent across fragment instance 924 * state save and restore. 925 * 926 * <p>An app may set this to false to indicate that the fragment's UI is 927 * scrolled out of visibility or is otherwise not directly visible to the user. 928 * This may be used by the system to prioritize operations such as fragment lifecycle updates 929 * or loader ordering behavior.</p> 930 * 931 * @param isVisibleToUser true if this fragment's UI is currently visible to the user (default), 932 * false if it is not. 933 */ 934 public void setUserVisibleHint(boolean isVisibleToUser) { 935 if (!mUserVisibleHint && isVisibleToUser && mState < STARTED) { 936 mFragmentManager.performPendingDeferredStart(this); 937 } 938 mUserVisibleHint = isVisibleToUser; 939 mDeferStart = !isVisibleToUser; 940 } 941 942 /** 943 * @return The current value of the user-visible hint on this fragment. 944 * @see #setUserVisibleHint(boolean) 945 */ 946 public boolean getUserVisibleHint() { 947 return mUserVisibleHint; 948 } 949 950 /** 951 * Return the LoaderManager for this fragment, creating it if needed. 952 */ 953 public LoaderManager getLoaderManager() { 954 if (mLoaderManager != null) { 955 return mLoaderManager; 956 } 957 if (mActivity == null) { 958 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 959 } 960 mCheckedForLoaderManager = true; 961 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, true); 962 return mLoaderManager; 963 } 964 965 /** 966 * Call {@link Activity#startActivity(Intent)} on the fragment's 967 * containing Activity. 968 */ 969 public void startActivity(Intent intent) { 970 if (mActivity == null) { 971 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 972 } 973 mActivity.startActivityFromFragment(this, intent, -1); 974 } 975 976 /** 977 * Call {@link Activity#startActivityForResult(Intent, int)} on the fragment's 978 * containing Activity. 979 */ 980 public void startActivityForResult(Intent intent, int requestCode) { 981 if (mActivity == null) { 982 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 983 } 984 mActivity.startActivityFromFragment(this, intent, requestCode); 985 } 986 987 /** 988 * Receive the result from a previous call to 989 * {@link #startActivityForResult(Intent, int)}. This follows the 990 * related Activity API as described there in 991 * {@link Activity#onActivityResult(int, int, Intent)}. 992 * 993 * @param requestCode The integer request code originally supplied to 994 * startActivityForResult(), allowing you to identify who this 995 * result came from. 996 * @param resultCode The integer result code returned by the child activity 997 * through its setResult(). 998 * @param data An Intent, which can return result data to the caller 999 * (various data can be attached to Intent "extras"). 1000 */ 1001 public void onActivityResult(int requestCode, int resultCode, Intent data) { 1002 } 1003 1004 /** 1005 * @hide Hack so that DialogFragment can make its Dialog before creating 1006 * its views, and the view construction can use the dialog's context for 1007 * inflation. Maybe this should become a public API. Note sure. 1008 */ 1009 public LayoutInflater getLayoutInflater(Bundle savedInstanceState) { 1010 return mActivity.getLayoutInflater(); 1011 } 1012 1013 /** 1014 * @deprecated Use {@link #onInflate(Activity, AttributeSet, Bundle)} instead. 1015 */ 1016 @Deprecated 1017 public void onInflate(AttributeSet attrs, Bundle savedInstanceState) { 1018 mCalled = true; 1019 } 1020 1021 /** 1022 * Called when a fragment is being created as part of a view layout 1023 * inflation, typically from setting the content view of an activity. This 1024 * may be called immediately after the fragment is created from a <fragment> 1025 * tag in a layout file. Note this is <em>before</em> the fragment's 1026 * {@link #onAttach(Activity)} has been called; all you should do here is 1027 * parse the attributes and save them away. 1028 * 1029 * <p>This is called every time the fragment is inflated, even if it is 1030 * being inflated into a new instance with saved state. It typically makes 1031 * sense to re-parse the parameters each time, to allow them to change with 1032 * different configurations.</p> 1033 * 1034 * <p>Here is a typical implementation of a fragment that can take parameters 1035 * both through attributes supplied here as well from {@link #getArguments()}:</p> 1036 * 1037 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1038 * fragment} 1039 * 1040 * <p>Note that parsing the XML attributes uses a "styleable" resource. The 1041 * declaration for the styleable used here is:</p> 1042 * 1043 * {@sample development/samples/ApiDemos/res/values/attrs.xml fragment_arguments} 1044 * 1045 * <p>The fragment can then be declared within its activity's content layout 1046 * through a tag like this:</p> 1047 * 1048 * {@sample development/samples/ApiDemos/res/layout/fragment_arguments.xml from_attributes} 1049 * 1050 * <p>This fragment can also be created dynamically from arguments given 1051 * at runtime in the arguments Bundle; here is an example of doing so at 1052 * creation of the containing activity:</p> 1053 * 1054 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 1055 * create} 1056 * 1057 * @param activity The Activity that is inflating this fragment. 1058 * @param attrs The attributes at the tag where the fragment is 1059 * being created. 1060 * @param savedInstanceState If the fragment is being re-created from 1061 * a previous saved state, this is the state. 1062 */ 1063 public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) { 1064 onInflate(attrs, savedInstanceState); 1065 mCalled = true; 1066 } 1067 1068 /** 1069 * Called when a fragment is first attached to its activity. 1070 * {@link #onCreate(Bundle)} will be called after this. 1071 */ 1072 public void onAttach(Activity activity) { 1073 mCalled = true; 1074 } 1075 1076 /** 1077 * Called when a fragment loads an animation. 1078 */ 1079 public Animator onCreateAnimator(int transit, boolean enter, int nextAnim) { 1080 return null; 1081 } 1082 1083 /** 1084 * Called to do initial creation of a fragment. This is called after 1085 * {@link #onAttach(Activity)} and before 1086 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 1087 * 1088 * <p>Note that this can be called while the fragment's activity is 1089 * still in the process of being created. As such, you can not rely 1090 * on things like the activity's content view hierarchy being initialized 1091 * at this point. If you want to do work once the activity itself is 1092 * created, see {@link #onActivityCreated(Bundle)}. 1093 * 1094 * @param savedInstanceState If the fragment is being re-created from 1095 * a previous saved state, this is the state. 1096 */ 1097 public void onCreate(Bundle savedInstanceState) { 1098 mCalled = true; 1099 } 1100 1101 /** 1102 * Called immediately after {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} 1103 * has returned, but before any saved state has been restored in to the view. 1104 * This gives subclasses a chance to initialize themselves once 1105 * they know their view hierarchy has been completely created. The fragment's 1106 * view hierarchy is not however attached to its parent at this point. 1107 * @param view The View returned by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 1108 * @param savedInstanceState If non-null, this fragment is being re-constructed 1109 * from a previous saved state as given here. 1110 */ 1111 public void onViewCreated(View view, Bundle savedInstanceState) { 1112 } 1113 1114 /** 1115 * Called to have the fragment instantiate its user interface view. 1116 * This is optional, and non-graphical fragments can return null (which 1117 * is the default implementation). This will be called between 1118 * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}. 1119 * 1120 * <p>If you return a View from here, you will later be called in 1121 * {@link #onDestroyView} when the view is being released. 1122 * 1123 * @param inflater The LayoutInflater object that can be used to inflate 1124 * any views in the fragment, 1125 * @param container If non-null, this is the parent view that the fragment's 1126 * UI should be attached to. The fragment should not add the view itself, 1127 * but this can be used to generate the LayoutParams of the view. 1128 * @param savedInstanceState If non-null, this fragment is being re-constructed 1129 * from a previous saved state as given here. 1130 * 1131 * @return Return the View for the fragment's UI, or null. 1132 */ 1133 public View onCreateView(LayoutInflater inflater, ViewGroup container, 1134 Bundle savedInstanceState) { 1135 return null; 1136 } 1137 1138 /** 1139 * Get the root view for the fragment's layout (the one returned by {@link #onCreateView}), 1140 * if provided. 1141 * 1142 * @return The fragment's root view, or null if it has no layout. 1143 */ 1144 public View getView() { 1145 return mView; 1146 } 1147 1148 /** 1149 * Called when the fragment's activity has been created and this 1150 * fragment's view hierarchy instantiated. It can be used to do final 1151 * initialization once these pieces are in place, such as retrieving 1152 * views or restoring state. It is also useful for fragments that use 1153 * {@link #setRetainInstance(boolean)} to retain their instance, 1154 * as this callback tells the fragment when it is fully associated with 1155 * the new activity instance. This is called after {@link #onCreateView} 1156 * and before {@link #onStart()}. 1157 * 1158 * @param savedInstanceState If the fragment is being re-created from 1159 * a previous saved state, this is the state. 1160 */ 1161 public void onActivityCreated(Bundle savedInstanceState) { 1162 mCalled = true; 1163 } 1164 1165 /** 1166 * Called when the Fragment is visible to the user. This is generally 1167 * tied to {@link Activity#onStart() Activity.onStart} of the containing 1168 * Activity's lifecycle. 1169 */ 1170 public void onStart() { 1171 mCalled = true; 1172 1173 if (!mLoadersStarted) { 1174 mLoadersStarted = true; 1175 if (!mCheckedForLoaderManager) { 1176 mCheckedForLoaderManager = true; 1177 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 1178 } 1179 if (mLoaderManager != null) { 1180 mLoaderManager.doStart(); 1181 } 1182 } 1183 } 1184 1185 /** 1186 * Called when the fragment is visible to the user and actively running. 1187 * This is generally 1188 * tied to {@link Activity#onResume() Activity.onResume} of the containing 1189 * Activity's lifecycle. 1190 */ 1191 public void onResume() { 1192 mCalled = true; 1193 } 1194 1195 /** 1196 * Called to ask the fragment to save its current dynamic state, so it 1197 * can later be reconstructed in a new instance of its process is 1198 * restarted. If a new instance of the fragment later needs to be 1199 * created, the data you place in the Bundle here will be available 1200 * in the Bundle given to {@link #onCreate(Bundle)}, 1201 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, and 1202 * {@link #onActivityCreated(Bundle)}. 1203 * 1204 * <p>This corresponds to {@link Activity#onSaveInstanceState(Bundle) 1205 * Activity.onSaveInstanceState(Bundle)} and most of the discussion there 1206 * applies here as well. Note however: <em>this method may be called 1207 * at any time before {@link #onDestroy()}</em>. There are many situations 1208 * where a fragment may be mostly torn down (such as when placed on the 1209 * back stack with no UI showing), but its state will not be saved until 1210 * its owning activity actually needs to save its state. 1211 * 1212 * @param outState Bundle in which to place your saved state. 1213 */ 1214 public void onSaveInstanceState(Bundle outState) { 1215 } 1216 1217 public void onConfigurationChanged(Configuration newConfig) { 1218 mCalled = true; 1219 } 1220 1221 /** 1222 * Called when the Fragment is no longer resumed. This is generally 1223 * tied to {@link Activity#onPause() Activity.onPause} of the containing 1224 * Activity's lifecycle. 1225 */ 1226 public void onPause() { 1227 mCalled = true; 1228 } 1229 1230 /** 1231 * Called when the Fragment is no longer started. This is generally 1232 * tied to {@link Activity#onStop() Activity.onStop} of the containing 1233 * Activity's lifecycle. 1234 */ 1235 public void onStop() { 1236 mCalled = true; 1237 } 1238 1239 public void onLowMemory() { 1240 mCalled = true; 1241 } 1242 1243 public void onTrimMemory(int level) { 1244 mCalled = true; 1245 } 1246 1247 /** 1248 * Called when the view previously created by {@link #onCreateView} has 1249 * been detached from the fragment. The next time the fragment needs 1250 * to be displayed, a new view will be created. This is called 1251 * after {@link #onStop()} and before {@link #onDestroy()}. It is called 1252 * <em>regardless</em> of whether {@link #onCreateView} returned a 1253 * non-null view. Internally it is called after the view's state has 1254 * been saved but before it has been removed from its parent. 1255 */ 1256 public void onDestroyView() { 1257 mCalled = true; 1258 } 1259 1260 /** 1261 * Called when the fragment is no longer in use. This is called 1262 * after {@link #onStop()} and before {@link #onDetach()}. 1263 */ 1264 public void onDestroy() { 1265 mCalled = true; 1266 //Log.v("foo", "onDestroy: mCheckedForLoaderManager=" + mCheckedForLoaderManager 1267 // + " mLoaderManager=" + mLoaderManager); 1268 if (!mCheckedForLoaderManager) { 1269 mCheckedForLoaderManager = true; 1270 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 1271 } 1272 if (mLoaderManager != null) { 1273 mLoaderManager.doDestroy(); 1274 } 1275 } 1276 1277 /** 1278 * Called by the fragment manager once this fragment has been removed, 1279 * so that we don't have any left-over state if the application decides 1280 * to re-use the instance. This only clears state that the framework 1281 * internally manages, not things the application sets. 1282 */ 1283 void initState() { 1284 mIndex = -1; 1285 mWho = null; 1286 mAdded = false; 1287 mRemoving = false; 1288 mResumed = false; 1289 mFromLayout = false; 1290 mInLayout = false; 1291 mRestored = false; 1292 mBackStackNesting = 0; 1293 mFragmentManager = null; 1294 mActivity = null; 1295 mFragmentId = 0; 1296 mContainerId = 0; 1297 mTag = null; 1298 mHidden = false; 1299 mDetached = false; 1300 mRetaining = false; 1301 mLoaderManager = null; 1302 mLoadersStarted = false; 1303 mCheckedForLoaderManager = false; 1304 } 1305 1306 /** 1307 * Called when the fragment is no longer attached to its activity. This 1308 * is called after {@link #onDestroy()}. 1309 */ 1310 public void onDetach() { 1311 mCalled = true; 1312 } 1313 1314 /** 1315 * Initialize the contents of the Activity's standard options menu. You 1316 * should place your menu items in to <var>menu</var>. For this method 1317 * to be called, you must have first called {@link #setHasOptionsMenu}. See 1318 * {@link Activity#onCreateOptionsMenu(Menu) Activity.onCreateOptionsMenu} 1319 * for more information. 1320 * 1321 * @param menu The options menu in which you place your items. 1322 * 1323 * @see #setHasOptionsMenu 1324 * @see #onPrepareOptionsMenu 1325 * @see #onOptionsItemSelected 1326 */ 1327 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 1328 } 1329 1330 /** 1331 * Prepare the Screen's standard options menu to be displayed. This is 1332 * called right before the menu is shown, every time it is shown. You can 1333 * use this method to efficiently enable/disable items or otherwise 1334 * dynamically modify the contents. See 1335 * {@link Activity#onPrepareOptionsMenu(Menu) Activity.onPrepareOptionsMenu} 1336 * for more information. 1337 * 1338 * @param menu The options menu as last shown or first initialized by 1339 * onCreateOptionsMenu(). 1340 * 1341 * @see #setHasOptionsMenu 1342 * @see #onCreateOptionsMenu 1343 */ 1344 public void onPrepareOptionsMenu(Menu menu) { 1345 } 1346 1347 /** 1348 * Called when this fragment's option menu items are no longer being 1349 * included in the overall options menu. Receiving this call means that 1350 * the menu needed to be rebuilt, but this fragment's items were not 1351 * included in the newly built menu (its {@link #onCreateOptionsMenu(Menu, MenuInflater)} 1352 * was not called). 1353 */ 1354 public void onDestroyOptionsMenu() { 1355 } 1356 1357 /** 1358 * This hook is called whenever an item in your options menu is selected. 1359 * The default implementation simply returns false to have the normal 1360 * processing happen (calling the item's Runnable or sending a message to 1361 * its Handler as appropriate). You can use this method for any items 1362 * for which you would like to do processing without those other 1363 * facilities. 1364 * 1365 * <p>Derived classes should call through to the base class for it to 1366 * perform the default menu handling. 1367 * 1368 * @param item The menu item that was selected. 1369 * 1370 * @return boolean Return false to allow normal menu processing to 1371 * proceed, true to consume it here. 1372 * 1373 * @see #onCreateOptionsMenu 1374 */ 1375 public boolean onOptionsItemSelected(MenuItem item) { 1376 return false; 1377 } 1378 1379 /** 1380 * This hook is called whenever the options menu is being closed (either by the user canceling 1381 * the menu with the back/menu button, or when an item is selected). 1382 * 1383 * @param menu The options menu as last shown or first initialized by 1384 * onCreateOptionsMenu(). 1385 */ 1386 public void onOptionsMenuClosed(Menu menu) { 1387 } 1388 1389 /** 1390 * Called when a context menu for the {@code view} is about to be shown. 1391 * Unlike {@link #onCreateOptionsMenu}, this will be called every 1392 * time the context menu is about to be shown and should be populated for 1393 * the view (or item inside the view for {@link AdapterView} subclasses, 1394 * this can be found in the {@code menuInfo})). 1395 * <p> 1396 * Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an 1397 * item has been selected. 1398 * <p> 1399 * The default implementation calls up to 1400 * {@link Activity#onCreateContextMenu Activity.onCreateContextMenu}, though 1401 * you can not call this implementation if you don't want that behavior. 1402 * <p> 1403 * It is not safe to hold onto the context menu after this method returns. 1404 * {@inheritDoc} 1405 */ 1406 public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { 1407 getActivity().onCreateContextMenu(menu, v, menuInfo); 1408 } 1409 1410 /** 1411 * Registers a context menu to be shown for the given view (multiple views 1412 * can show the context menu). This method will set the 1413 * {@link OnCreateContextMenuListener} on the view to this fragment, so 1414 * {@link #onCreateContextMenu(ContextMenu, View, ContextMenuInfo)} will be 1415 * called when it is time to show the context menu. 1416 * 1417 * @see #unregisterForContextMenu(View) 1418 * @param view The view that should show a context menu. 1419 */ 1420 public void registerForContextMenu(View view) { 1421 view.setOnCreateContextMenuListener(this); 1422 } 1423 1424 /** 1425 * Prevents a context menu to be shown for the given view. This method will 1426 * remove the {@link OnCreateContextMenuListener} on the view. 1427 * 1428 * @see #registerForContextMenu(View) 1429 * @param view The view that should stop showing a context menu. 1430 */ 1431 public void unregisterForContextMenu(View view) { 1432 view.setOnCreateContextMenuListener(null); 1433 } 1434 1435 /** 1436 * This hook is called whenever an item in a context menu is selected. The 1437 * default implementation simply returns false to have the normal processing 1438 * happen (calling the item's Runnable or sending a message to its Handler 1439 * as appropriate). You can use this method for any items for which you 1440 * would like to do processing without those other facilities. 1441 * <p> 1442 * Use {@link MenuItem#getMenuInfo()} to get extra information set by the 1443 * View that added this menu item. 1444 * <p> 1445 * Derived classes should call through to the base class for it to perform 1446 * the default menu handling. 1447 * 1448 * @param item The context menu item that was selected. 1449 * @return boolean Return false to allow normal context menu processing to 1450 * proceed, true to consume it here. 1451 */ 1452 public boolean onContextItemSelected(MenuItem item) { 1453 return false; 1454 } 1455 1456 /** 1457 * Print the Fragments's state into the given stream. 1458 * 1459 * @param prefix Text to print at the front of each line. 1460 * @param fd The raw file descriptor that the dump is being sent to. 1461 * @param writer The PrintWriter to which you should dump your state. This will be 1462 * closed for you after you return. 1463 * @param args additional arguments to the dump request. 1464 */ 1465 public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) { 1466 writer.print(prefix); writer.print("mFragmentId=#"); 1467 writer.print(Integer.toHexString(mFragmentId)); 1468 writer.print(" mContainerId#="); 1469 writer.print(Integer.toHexString(mContainerId)); 1470 writer.print(" mTag="); writer.println(mTag); 1471 writer.print(prefix); writer.print("mState="); writer.print(mState); 1472 writer.print(" mIndex="); writer.print(mIndex); 1473 writer.print(" mWho="); writer.print(mWho); 1474 writer.print(" mBackStackNesting="); writer.println(mBackStackNesting); 1475 writer.print(prefix); writer.print("mAdded="); writer.print(mAdded); 1476 writer.print(" mRemoving="); writer.print(mRemoving); 1477 writer.print(" mResumed="); writer.print(mResumed); 1478 writer.print(" mFromLayout="); writer.print(mFromLayout); 1479 writer.print(" mInLayout="); writer.println(mInLayout); 1480 writer.print(prefix); writer.print("mHidden="); writer.print(mHidden); 1481 writer.print(" mDetached="); writer.print(mDetached); 1482 writer.print(" mMenuVisible="); writer.print(mMenuVisible); 1483 writer.print(" mHasMenu="); writer.println(mHasMenu); 1484 writer.print(prefix); writer.print("mRetainInstance="); writer.print(mRetainInstance); 1485 writer.print(" mRetaining="); writer.print(mRetaining); 1486 writer.print(" mUserVisibleHint="); writer.println(mUserVisibleHint); 1487 if (mFragmentManager != null) { 1488 writer.print(prefix); writer.print("mFragmentManager="); 1489 writer.println(mFragmentManager); 1490 } 1491 if (mActivity != null) { 1492 writer.print(prefix); writer.print("mActivity="); 1493 writer.println(mActivity); 1494 } 1495 if (mArguments != null) { 1496 writer.print(prefix); writer.print("mArguments="); writer.println(mArguments); 1497 } 1498 if (mSavedFragmentState != null) { 1499 writer.print(prefix); writer.print("mSavedFragmentState="); 1500 writer.println(mSavedFragmentState); 1501 } 1502 if (mSavedViewState != null) { 1503 writer.print(prefix); writer.print("mSavedViewState="); 1504 writer.println(mSavedViewState); 1505 } 1506 if (mTarget != null) { 1507 writer.print(prefix); writer.print("mTarget="); writer.print(mTarget); 1508 writer.print(" mTargetRequestCode="); 1509 writer.println(mTargetRequestCode); 1510 } 1511 if (mNextAnim != 0) { 1512 writer.print(prefix); writer.print("mNextAnim="); writer.println(mNextAnim); 1513 } 1514 if (mContainer != null) { 1515 writer.print(prefix); writer.print("mContainer="); writer.println(mContainer); 1516 } 1517 if (mView != null) { 1518 writer.print(prefix); writer.print("mView="); writer.println(mView); 1519 } 1520 if (mAnimatingAway != null) { 1521 writer.print(prefix); writer.print("mAnimatingAway="); writer.println(mAnimatingAway); 1522 writer.print(prefix); writer.print("mStateAfterAnimating="); 1523 writer.println(mStateAfterAnimating); 1524 } 1525 if (mLoaderManager != null) { 1526 writer.print(prefix); writer.println("Loader Manager:"); 1527 mLoaderManager.dump(prefix + " ", fd, writer, args); 1528 } 1529 } 1530 1531 void performStart() { 1532 onStart(); 1533 if (mLoaderManager != null) { 1534 mLoaderManager.doReportStart(); 1535 } 1536 } 1537 1538 void performStop() { 1539 onStop(); 1540 1541 if (mLoadersStarted) { 1542 mLoadersStarted = false; 1543 if (!mCheckedForLoaderManager) { 1544 mCheckedForLoaderManager = true; 1545 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 1546 } 1547 if (mLoaderManager != null) { 1548 if (mActivity == null || !mActivity.mChangingConfigurations) { 1549 mLoaderManager.doStop(); 1550 } else { 1551 mLoaderManager.doRetain(); 1552 } 1553 } 1554 } 1555 } 1556 1557 void performDestroyView() { 1558 onDestroyView(); 1559 if (mLoaderManager != null) { 1560 mLoaderManager.doReportNextStart(); 1561 } 1562 } 1563} 1564