Fragment.java revision 9277b9e4419c1f0b5236d9b573a7cc0b23d56402
1/* 2 * Copyright (C) 2011 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.support.v4.app; 18 19import android.app.Activity; 20import android.content.ComponentCallbacks; 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.support.v4.util.DebugUtils; 29import android.util.AttributeSet; 30import android.util.SparseArray; 31import android.view.ContextMenu; 32import android.view.LayoutInflater; 33import android.view.Menu; 34import android.view.MenuInflater; 35import android.view.MenuItem; 36import android.view.View; 37import android.view.ViewGroup; 38import android.view.ContextMenu.ContextMenuInfo; 39import android.view.View.OnCreateContextMenuListener; 40import android.view.animation.Animation; 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 Bundle mArguments; 56 57 Bundle mSavedFragmentState; 58 59 Fragment mInstance; 60 61 public FragmentState(Fragment frag) { 62 mClassName = frag.getClass().getName(); 63 mIndex = frag.mIndex; 64 mFromLayout = frag.mFromLayout; 65 mFragmentId = frag.mFragmentId; 66 mContainerId = frag.mContainerId; 67 mTag = frag.mTag; 68 mRetainInstance = frag.mRetainInstance; 69 mArguments = frag.mArguments; 70 } 71 72 public FragmentState(Parcel in) { 73 mClassName = in.readString(); 74 mIndex = in.readInt(); 75 mFromLayout = in.readInt() != 0; 76 mFragmentId = in.readInt(); 77 mContainerId = in.readInt(); 78 mTag = in.readString(); 79 mRetainInstance = in.readInt() != 0; 80 mArguments = in.readBundle(); 81 mSavedFragmentState = in.readBundle(); 82 } 83 84 public Fragment instantiate(FragmentActivity activity) { 85 if (mInstance != null) { 86 return mInstance; 87 } 88 89 if (mArguments != null) { 90 mArguments.setClassLoader(activity.getClassLoader()); 91 } 92 93 mInstance = Fragment.instantiate(activity, mClassName, mArguments); 94 95 if (mSavedFragmentState != null) { 96 mSavedFragmentState.setClassLoader(activity.getClassLoader()); 97 mInstance.mSavedFragmentState = mSavedFragmentState; 98 } 99 mInstance.setIndex(mIndex); 100 mInstance.mFromLayout = mFromLayout; 101 mInstance.mRestored = true; 102 mInstance.mFragmentId = mFragmentId; 103 mInstance.mContainerId = mContainerId; 104 mInstance.mTag = mTag; 105 mInstance.mRetainInstance = mRetainInstance; 106 mInstance.mFragmentManager = activity.mFragments; 107 108 return mInstance; 109 } 110 111 public int describeContents() { 112 return 0; 113 } 114 115 public void writeToParcel(Parcel dest, int flags) { 116 dest.writeString(mClassName); 117 dest.writeInt(mIndex); 118 dest.writeInt(mFromLayout ? 1 : 0); 119 dest.writeInt(mFragmentId); 120 dest.writeInt(mContainerId); 121 dest.writeString(mTag); 122 dest.writeInt(mRetainInstance ? 1 : 0); 123 dest.writeBundle(mArguments); 124 dest.writeBundle(mSavedFragmentState); 125 } 126 127 public static final Parcelable.Creator<FragmentState> CREATOR 128 = new Parcelable.Creator<FragmentState>() { 129 public FragmentState createFromParcel(Parcel in) { 130 return new FragmentState(in); 131 } 132 133 public FragmentState[] newArray(int size) { 134 return new FragmentState[size]; 135 } 136 }; 137} 138 139/** 140 * Static library support version of the framework's {@link android.app.Fragment}. 141 * Used to write apps that run on platforms prior to Android 3.0. When running 142 * on Android 3.0 or above, this implementation is still used; it does not try 143 * to switch to the framework's implementation. See the framework SDK 144 * documentation for a class overview. 145 */ 146public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener { 147 private static final HashMap<String, Class<?>> sClassMap = 148 new HashMap<String, Class<?>>(); 149 150 static final int INITIALIZING = 0; // Not yet created. 151 static final int CREATED = 1; // Created. 152 static final int ACTIVITY_CREATED = 2; // The activity has finished its creation. 153 static final int STARTED = 3; // Created and started, not resumed. 154 static final int RESUMED = 4; // Created started and resumed. 155 156 int mState = INITIALIZING; 157 158 // Non-null if the fragment's view hierarchy is currently animating away, 159 // meaning we need to wait a bit on completely destroying it. This is the 160 // view that is animating. 161 View mAnimatingAway; 162 163 // If mAnimatingAway != null, this is the state we should move to once the 164 // animation is done. 165 int mStateAfterAnimating; 166 167 // When instantiated from saved state, this is the saved state. 168 Bundle mSavedFragmentState; 169 SparseArray<Parcelable> mSavedViewState; 170 171 // Index into active fragment array. 172 int mIndex = -1; 173 174 // Internal unique name for this fragment; 175 String mWho; 176 177 // Construction arguments; 178 Bundle mArguments; 179 180 // Target fragment. 181 Fragment mTarget; 182 183 // Target request code. 184 int mTargetRequestCode; 185 186 // True if the fragment is in the list of added fragments. 187 boolean mAdded; 188 189 // If set this fragment is being removed from its activity. 190 boolean mRemoving; 191 192 // True if the fragment is in the resumed state. 193 boolean mResumed; 194 195 // Set to true if this fragment was instantiated from a layout file. 196 boolean mFromLayout; 197 198 // Set to true when the view has actually been inflated in its layout. 199 boolean mInLayout; 200 201 // True if this fragment has been restored from previously saved state. 202 boolean mRestored; 203 204 // Number of active back stack entries this fragment is in. 205 int mBackStackNesting; 206 207 // The fragment manager we are associated with. Set as soon as the 208 // fragment is used in a transaction; cleared after it has been removed 209 // from all transactions. 210 FragmentManager mFragmentManager; 211 212 // Set as soon as a fragment is added to a transaction (or removed), 213 // to be able to do validation. 214 FragmentActivity mImmediateActivity; 215 216 // Activity this fragment is attached to. 217 FragmentActivity mActivity; 218 219 // The optional identifier for this fragment -- either the container ID if it 220 // was dynamically added to the view hierarchy, or the ID supplied in 221 // layout. 222 int mFragmentId; 223 224 // When a fragment is being dynamically added to the view hierarchy, this 225 // is the identifier of the parent container it is being added to. 226 int mContainerId; 227 228 // The optional named tag for this fragment -- usually used to find 229 // fragments that are not part of the layout. 230 String mTag; 231 232 // Set to true when the app has requested that this fragment be hidden 233 // from the user. 234 boolean mHidden; 235 236 // If set this fragment would like its instance retained across 237 // configuration changes. 238 boolean mRetainInstance; 239 240 // If set this fragment is being retained across the current config change. 241 boolean mRetaining; 242 243 // If set this fragment has menu items to contribute. 244 boolean mHasMenu; 245 246 // Used to verify that subclasses call through to super class. 247 boolean mCalled; 248 249 // If app has requested a specific animation, this is the one to use. 250 int mNextAnim; 251 252 // The parent container of the fragment after dynamically added to UI. 253 ViewGroup mContainer; 254 255 // The View generated for this fragment. 256 View mView; 257 258 // The real inner view that will save/restore state. 259 View mInnerView; 260 261 LoaderManagerImpl mLoaderManager; 262 boolean mLoadersStarted; 263 boolean mCheckedForLoaderManager; 264 265 /** 266 * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when 267 * there is an instantiation failure. 268 */ 269 static public class InstantiationException extends RuntimeException { 270 public InstantiationException(String msg, Exception cause) { 271 super(msg, cause); 272 } 273 } 274 275 /** 276 * Default constructor. <strong>Every</strong> fragment must have an 277 * empty constructor, so it can be instantiated when restoring its 278 * activity's state. It is strongly recommended that subclasses do not 279 * have other constructors with parameters, since these constructors 280 * will not be called when the fragment is re-instantiated; instead, 281 * arguments can be supplied by the caller with {@link #setArguments} 282 * and later retrieved by the Fragment with {@link #getArguments}. 283 * 284 * <p>Applications should generally not implement a constructor. The 285 * first place application code an run where the fragment is ready to 286 * be used is in {@link #onAttach(Activity)}, the point where the fragment 287 * is actually associated with its activity. Some applications may also 288 * want to implement {@link #onInflate} to retrieve attributes from a 289 * layout resource, though should take care here because this happens for 290 * the fragment is attached to its activity. 291 */ 292 public Fragment() { 293 } 294 295 /** 296 * Like {@link #instantiate(Context, String, Bundle)} but with a null 297 * argument Bundle. 298 */ 299 public static Fragment instantiate(Context context, String fname) { 300 return instantiate(context, fname, null); 301 } 302 303 /** 304 * Create a new instance of a Fragment with the given class name. This is 305 * the same as calling its empty constructor. 306 * 307 * @param context The calling context being used to instantiate the fragment. 308 * This is currently just used to get its ClassLoader. 309 * @param fname The class name of the fragment to instantiate. 310 * @param args Bundle of arguments to supply to the fragment, which it 311 * can retrieve with {@link #getArguments()}. May be null. 312 * @return Returns a new fragment instance. 313 * @throws InstantiationException If there is a failure in instantiating 314 * the given fragment class. This is a runtime exception; it is not 315 * normally expected to happen. 316 */ 317 public static Fragment instantiate(Context context, String fname, Bundle args) { 318 try { 319 Class<?> clazz = sClassMap.get(fname); 320 if (clazz == null) { 321 // Class not found in the cache, see if it's real, and try to add it 322 clazz = context.getClassLoader().loadClass(fname); 323 sClassMap.put(fname, clazz); 324 } 325 Fragment f = (Fragment)clazz.newInstance(); 326 if (args != null) { 327 args.setClassLoader(f.getClass().getClassLoader()); 328 f.mArguments = args; 329 } 330 return f; 331 } catch (ClassNotFoundException e) { 332 throw new InstantiationException("Unable to instantiate fragment " + fname 333 + ": make sure class name exists, is public, and has an" 334 + " empty constructor that is public", e); 335 } catch (java.lang.InstantiationException e) { 336 throw new InstantiationException("Unable to instantiate fragment " + fname 337 + ": make sure class name exists, is public, and has an" 338 + " empty constructor that is public", e); 339 } catch (IllegalAccessException e) { 340 throw new InstantiationException("Unable to instantiate fragment " + fname 341 + ": make sure class name exists, is public, and has an" 342 + " empty constructor that is public", e); 343 } 344 } 345 346 void restoreViewState() { 347 if (mSavedViewState != null) { 348 mInnerView.restoreHierarchyState(mSavedViewState); 349 mSavedViewState = null; 350 } 351 } 352 353 void setIndex(int index) { 354 mIndex = index; 355 mWho = "android:fragment:" + mIndex; 356 } 357 358 void clearIndex() { 359 mIndex = -1; 360 mWho = null; 361 } 362 363 /** 364 * Subclasses can not override equals(). 365 */ 366 @Override final public boolean equals(Object o) { 367 return super.equals(o); 368 } 369 370 /** 371 * Subclasses can not override hashCode(). 372 */ 373 @Override final public int hashCode() { 374 return super.hashCode(); 375 } 376 377 @Override 378 public String toString() { 379 StringBuilder sb = new StringBuilder(128); 380 DebugUtils.buildShortClassTag(this, sb); 381 if (mIndex >= 0) { 382 sb.append(" #"); 383 sb.append(mIndex); 384 } 385 if (mFragmentId != 0) { 386 sb.append(" id=0x"); 387 sb.append(Integer.toHexString(mFragmentId)); 388 } 389 if (mTag != null) { 390 sb.append(" "); 391 sb.append(mTag); 392 } 393 sb.append('}'); 394 return sb.toString(); 395 } 396 397 /** 398 * Return the identifier this fragment is known by. This is either 399 * the android:id value supplied in a layout or the container view ID 400 * supplied when adding the fragment. 401 */ 402 final public int getId() { 403 return mFragmentId; 404 } 405 406 /** 407 * Get the tag name of the fragment, if specified. 408 */ 409 final public String getTag() { 410 return mTag; 411 } 412 413 /** 414 * Supply the construction arguments for this fragment. This can only 415 * be called before the fragment has been attached to its activity; that 416 * is, you should call it immediately after constructing the fragment. The 417 * arguments supplied here will be retained across fragment destroy and 418 * creation. 419 */ 420 public void setArguments(Bundle args) { 421 if (mIndex >= 0) { 422 throw new IllegalStateException("Fragment already active"); 423 } 424 mArguments = args; 425 } 426 427 /** 428 * Return the arguments supplied when the fragment was instantiated, 429 * if any. 430 */ 431 final public Bundle getArguments() { 432 return mArguments; 433 } 434 435 /** 436 * Optional target for this fragment. This may be used, for example, 437 * if this fragment is being started by another, and when done wants to 438 * give a result back to the first. The target set here is retained 439 * across instances via {@link FragmentManager#putFragment 440 * FragmentManager.putFragment()}. 441 * 442 * @param fragment The fragment that is the target of this one. 443 * @param requestCode Optional request code, for convenience if you 444 * are going to call back with {@link #onActivityResult(int, int, Intent)}. 445 */ 446 public void setTargetFragment(Fragment fragment, int requestCode) { 447 mTarget = fragment; 448 mTargetRequestCode = requestCode; 449 } 450 451 /** 452 * Return the target fragment set by {@link #setTargetFragment}. 453 */ 454 final public Fragment getTargetFragment() { 455 return mTarget; 456 } 457 458 /** 459 * Return the target request code set by {@link #setTargetFragment}. 460 */ 461 final public int getTargetRequestCode() { 462 return mTargetRequestCode; 463 } 464 465 /** 466 * Return the Activity this fragment is currently associated with. 467 */ 468 final public FragmentActivity getActivity() { 469 return mActivity; 470 } 471 472 /** 473 * Return <code>getActivity().getResources()</code>. 474 */ 475 final public Resources getResources() { 476 if (mActivity == null) { 477 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 478 } 479 return mActivity.getResources(); 480 } 481 482 /** 483 * Return a localized, styled CharSequence from the application's package's 484 * default string table. 485 * 486 * @param resId Resource id for the CharSequence text 487 */ 488 public final CharSequence getText(int resId) { 489 return getResources().getText(resId); 490 } 491 492 /** 493 * Return a localized string from the application's package's 494 * default string table. 495 * 496 * @param resId Resource id for the string 497 */ 498 public final String getString(int resId) { 499 return getResources().getString(resId); 500 } 501 502 /** 503 * Return a localized formatted string from the application's package's 504 * default string table, substituting the format arguments as defined in 505 * {@link java.util.Formatter} and {@link java.lang.String#format}. 506 * 507 * @param resId Resource id for the format string 508 * @param formatArgs The format arguments that will be used for substitution. 509 */ 510 511 public final String getString(int resId, Object... formatArgs) { 512 return getResources().getString(resId, formatArgs); 513 } 514 515 /** 516 * Return the FragmentManager for interacting with fragments associated 517 * with this fragment's activity. Note that this will be non-null slightly 518 * before {@link #getActivity()}, during the time from when the fragment is 519 * placed in a {@link FragmentTransaction} until it is committed and 520 * attached to its activity. 521 */ 522 final public FragmentManager getFragmentManager() { 523 return mFragmentManager; 524 } 525 526 /** 527 * Return true if the fragment is currently added to its activity. 528 */ 529 final public boolean isAdded() { 530 return mActivity != null && mAdded; 531 } 532 533 /** 534 * Return true if this fragment is currently being removed from its 535 * activity. This is <em>not</em> whether its activity is finishing, but 536 * rather whether it is in the process of being removed from its activity. 537 */ 538 final public boolean isRemoving() { 539 return mRemoving; 540 } 541 542 /** 543 * Return true if the layout is included as part of an activity view 544 * hierarchy via the <fragment> tag. This will always be true when 545 * fragments are created through the <fragment> tag, <em>except</em> 546 * in the case where an old fragment is restored from a previous state and 547 * it does not appear in the layout of the current state. 548 */ 549 final public boolean isInLayout() { 550 return mInLayout; 551 } 552 553 /** 554 * Return true if the fragment is in the resumed state. This is true 555 * for the duration of {@link #onResume()} and {@link #onPause()} as well. 556 */ 557 final public boolean isResumed() { 558 return mResumed; 559 } 560 561 /** 562 * Return true if the fragment is currently visible to the user. This means 563 * it: (1) has been added, (2) has its view attached to the window, and 564 * (3) is not hidden. 565 */ 566 final public boolean isVisible() { 567 return isAdded() && !isHidden() && mView != null 568 && mView.getWindowToken() != null && mView.getVisibility() == View.VISIBLE; 569 } 570 571 /** 572 * Return true if the fragment has been hidden. By default fragments 573 * are shown. You can find out about changes to this state with 574 * {@link #onHiddenChanged}. Note that the hidden state is orthogonal 575 * to other states -- that is, to be visible to the user, a fragment 576 * must be both started and not hidden. 577 */ 578 final public boolean isHidden() { 579 return mHidden; 580 } 581 582 /** 583 * Called when the hidden state (as returned by {@link #isHidden()} of 584 * the fragment has changed. Fragments start out not hidden; this will 585 * be called whenever the fragment changes state from that. 586 * @param hidden True if the fragment is now hidden, false if it is not 587 * visible. 588 */ 589 public void onHiddenChanged(boolean hidden) { 590 } 591 592 /** 593 * Control whether a fragment instance is retained across Activity 594 * re-creation (such as from a configuration change). This can only 595 * be used with fragments not in the back stack. If set, the fragment 596 * lifecycle will be slightly different when an activity is recreated: 597 * <ul> 598 * <li> {@link #onDestroy()} will not be called (but {@link #onDetach()} still 599 * will be, because the fragment is being detached from its current activity). 600 * <li> {@link #onCreate(Bundle)} will not be called since the fragment 601 * is not being re-created. 602 * <li> {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} <b>will</b> 603 * still be called. 604 * </ul> 605 */ 606 public void setRetainInstance(boolean retain) { 607 mRetainInstance = retain; 608 } 609 610 final public boolean getRetainInstance() { 611 return mRetainInstance; 612 } 613 614 /** 615 * Report that this fragment would like to participate in populating 616 * the options menu by receiving a call to {@link #onCreateOptionsMenu} 617 * and related methods. 618 * 619 * @param hasMenu If true, the fragment has menu items to contribute. 620 */ 621 public void setHasOptionsMenu(boolean hasMenu) { 622 if (mHasMenu != hasMenu) { 623 mHasMenu = hasMenu; 624 if (isAdded() && !isHidden()) { 625 mActivity.supportInvalidateOptionsMenu(); 626 } 627 } 628 } 629 630 /** 631 * Return the LoaderManager for this fragment, creating it if needed. 632 */ 633 public LoaderManager getLoaderManager() { 634 if (mLoaderManager != null) { 635 return mLoaderManager; 636 } 637 if (mActivity == null) { 638 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 639 } 640 mCheckedForLoaderManager = true; 641 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, true); 642 return mLoaderManager; 643 } 644 645 /** 646 * Call {@link Activity#startActivity(Intent)} on the fragment's 647 * containing Activity. 648 */ 649 public void startActivity(Intent intent) { 650 if (mActivity == null) { 651 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 652 } 653 mActivity.startActivityFromFragment(this, intent, -1); 654 } 655 656 /** 657 * Call {@link Activity#startActivityForResult(Intent, int)} on the fragment's 658 * containing Activity. 659 */ 660 public void startActivityForResult(Intent intent, int requestCode) { 661 if (mActivity == null) { 662 throw new IllegalStateException("Fragment " + this + " not attached to Activity"); 663 } 664 mActivity.startActivityFromFragment(this, intent, requestCode); 665 } 666 667 /** 668 * Receive the result from a previous call to 669 * {@link #startActivityForResult(Intent, int)}. This follows the 670 * related Activity API as described there in 671 * {@link Activity#onActivityResult(int, int, Intent)}. 672 * 673 * @param requestCode The integer request code originally supplied to 674 * startActivityForResult(), allowing you to identify who this 675 * result came from. 676 * @param resultCode The integer result code returned by the child activity 677 * through its setResult(). 678 * @param data An Intent, which can return result data to the caller 679 * (various data can be attached to Intent "extras"). 680 */ 681 public void onActivityResult(int requestCode, int resultCode, Intent data) { 682 } 683 684 /** 685 * @hide Hack so that DialogFragment can make its Dialog before creating 686 * its views, and the view construction can use the dialog's context for 687 * inflation. Maybe this should become a public API. Note sure. 688 */ 689 public LayoutInflater getLayoutInflater(Bundle savedInstanceState) { 690 return mActivity.getLayoutInflater(); 691 } 692 693 /** 694 * Called when a fragment is being created as part of a view layout 695 * inflation, typically from setting the content view of an activity. This 696 * may be called immediately after the fragment is created from a <fragment> 697 * tag in a layout file. Note this is <em>before</em> the fragment's 698 * {@link #onAttach(Activity)} has been called; all you should do here is 699 * parse the attributes and save them away. 700 * 701 * <p>This is called every time the fragment is inflated, even if it is 702 * being inflated into a new instance with saved state. It typically makes 703 * sense to re-parse the parameters each time, to allow them to change with 704 * different configurations.</p> 705 * 706 * <p>Here is a typical implementation of a fragment that can take parameters 707 * both through attributes supplied here as well from {@link #getArguments()}:</p> 708 * 709 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 710 * fragment} 711 * 712 * <p>Note that parsing the XML attributes uses a "styleable" resource. The 713 * declaration for the styleable used here is:</p> 714 * 715 * {@sample development/samples/ApiDemos/res/values/attrs.xml fragment_arguments} 716 * 717 * <p>The fragment can then be declared within its activity's content layout 718 * through a tag like this:</p> 719 * 720 * {@sample development/samples/ApiDemos/res/layout/fragment_arguments.xml from_attributes} 721 * 722 * <p>This fragment can also be created dynamically from arguments given 723 * at runtime in the arguments Bundle; here is an example of doing so at 724 * creation of the containing activity:</p> 725 * 726 * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java 727 * create} 728 * 729 * @param activity The Activity that is inflating this fragment. 730 * @param attrs The attributes at the tag where the fragment is 731 * being created. 732 * @param savedInstanceState If the fragment is being re-created from 733 * a previous saved state, this is the state. 734 */ 735 public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) { 736 mCalled = true; 737 } 738 739 /** 740 * Called when a fragment is first attached to its activity. 741 * {@link #onCreate(Bundle)} will be called after this. 742 */ 743 public void onAttach(Activity activity) { 744 mCalled = true; 745 } 746 747 /** 748 * Called when a fragment loads an animation. 749 */ 750 public Animation onCreateAnimation(int transit, boolean enter, int nextAnim) { 751 return null; 752 } 753 754 /** 755 * Called to do initial creation of a fragment. This is called after 756 * {@link #onAttach(Activity)} and before 757 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. 758 * 759 * <p>Note that this can be called while the fragment's activity is 760 * still in the process of being created. As such, you can not rely 761 * on things like the activity's content view hierarchy being initialized 762 * at this point. If you want to do work once the activity itself is 763 * created, see {@link #onActivityCreated(Bundle)}. 764 * 765 * @param savedInstanceState If the fragment is being re-created from 766 * a previous saved state, this is the state. 767 */ 768 public void onCreate(Bundle savedInstanceState) { 769 mCalled = true; 770 } 771 772 /** 773 * Called to have the fragment instantiate its user interface view. 774 * This is optional, and non-graphical fragments can return null (which 775 * is the default implementation). This will be called between 776 * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}. 777 * 778 * <p>If you return a View from here, you will later be called in 779 * {@link #onDestroyView} when the view is being released. 780 * 781 * @param inflater The LayoutInflater object that can be used to inflate 782 * any views in the fragment, 783 * @param container If non-null, this is the parent view that the fragment's 784 * UI should be attached to. The fragment should not add the view itself, 785 * but this can be used to generate the LayoutParams of the view. 786 * @param savedInstanceState If non-null, this fragment is being re-constructed 787 * from a previous saved state as given here. 788 * 789 * @return Return the View for the fragment's UI, or null. 790 */ 791 public View onCreateView(LayoutInflater inflater, ViewGroup container, 792 Bundle savedInstanceState) { 793 return null; 794 } 795 796 /** 797 * Get the root view for the fragment's layout (the one returned by {@link #onCreateView}), 798 * if provided. 799 * 800 * @return The fragment's root view, or null if it has no layout. 801 */ 802 public View getView() { 803 return mView; 804 } 805 806 /** 807 * Called when the fragment's activity has been created and this 808 * fragment's view hierarchy instantiated. It can be used to do final 809 * initialization once these pieces are in place, such as retrieving 810 * views or restoring state. It is also useful for fragments that use 811 * {@link #setRetainInstance(boolean)} to retain their instance, 812 * as this callback tells the fragment when it is fully associated with 813 * the new activity instance. This is called after {@link #onCreateView} 814 * and before {@link #onStart()}. 815 * 816 * @param savedInstanceState If the fragment is being re-created from 817 * a previous saved state, this is the state. 818 */ 819 public void onActivityCreated(Bundle savedInstanceState) { 820 mCalled = true; 821 } 822 823 /** 824 * Called when the Fragment is visible to the user. This is generally 825 * tied to {@link Activity#onStart() Activity.onStart} of the containing 826 * Activity's lifecycle. 827 */ 828 public void onStart() { 829 mCalled = true; 830 831 if (!mLoadersStarted) { 832 mLoadersStarted = true; 833 if (!mCheckedForLoaderManager) { 834 mCheckedForLoaderManager = true; 835 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 836 } 837 if (mLoaderManager != null) { 838 mLoaderManager.doStart(); 839 } 840 } 841 } 842 843 /** 844 * Called when the fragment is visible to the user and actively running. 845 * This is generally 846 * tied to {@link Activity#onResume() Activity.onResume} of the containing 847 * Activity's lifecycle. 848 */ 849 public void onResume() { 850 mCalled = true; 851 } 852 853 /** 854 * Called to ask the fragment to save its current dynamic state, so it 855 * can later be reconstructed in a new instance of its process is 856 * restarted. If a new instance of the fragment later needs to be 857 * created, the data you place in the Bundle here will be available 858 * in the Bundle given to {@link #onCreate(Bundle)}, 859 * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, and 860 * {@link #onActivityCreated(Bundle)}. 861 * 862 * <p>This corresponds to {@link Activity#onSaveInstanceState(Bundle) 863 * Activity.onSaveInstanceState(Bundle)} and most of the discussion there 864 * applies here as well. Note however: <em>this method may be called 865 * at any time before {@link #onDestroy()}</em>. There are many situations 866 * where a fragment may be mostly torn down (such as when placed on the 867 * back stack with no UI showing), but its state will not be saved until 868 * its owning activity actually needs to save its state. 869 * 870 * @param outState Bundle in which to place your saved state. 871 */ 872 public void onSaveInstanceState(Bundle outState) { 873 } 874 875 public void onConfigurationChanged(Configuration newConfig) { 876 mCalled = true; 877 } 878 879 /** 880 * Called when the Fragment is no longer resumed. This is generally 881 * tied to {@link Activity#onPause() Activity.onPause} of the containing 882 * Activity's lifecycle. 883 */ 884 public void onPause() { 885 mCalled = true; 886 } 887 888 /** 889 * Called when the Fragment is no longer started. This is generally 890 * tied to {@link Activity#onStop() Activity.onStop} of the containing 891 * Activity's lifecycle. 892 */ 893 public void onStop() { 894 mCalled = true; 895 } 896 897 public void onLowMemory() { 898 mCalled = true; 899 } 900 901 /** 902 * Called when the view previously created by {@link #onCreateView} has 903 * been detached from the fragment. The next time the fragment needs 904 * to be displayed, a new view will be created. This is called 905 * after {@link #onStop()} and before {@link #onDestroy()}. It is called 906 * <em>regardless</em> of whether {@link #onCreateView} returned a 907 * non-null view. Internally it is called after the view's state has 908 * been saved but before it has been removed from its parent. 909 */ 910 public void onDestroyView() { 911 mCalled = true; 912 } 913 914 /** 915 * Called when the fragment is no longer in use. This is called 916 * after {@link #onStop()} and before {@link #onDetach()}. 917 */ 918 public void onDestroy() { 919 mCalled = true; 920 //Log.v("foo", "onDestroy: mCheckedForLoaderManager=" + mCheckedForLoaderManager 921 // + " mLoaderManager=" + mLoaderManager); 922 if (!mCheckedForLoaderManager) { 923 mCheckedForLoaderManager = true; 924 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 925 } 926 if (mLoaderManager != null) { 927 mLoaderManager.doDestroy(); 928 } 929 } 930 931 /** 932 * Called when the fragment is no longer attached to its activity. This 933 * is called after {@link #onDestroy()}. 934 */ 935 public void onDetach() { 936 mCalled = true; 937 } 938 939 /** 940 * Initialize the contents of the Activity's standard options menu. You 941 * should place your menu items in to <var>menu</var>. For this method 942 * to be called, you must have first called {@link #setHasOptionsMenu}. See 943 * {@link Activity#onCreateOptionsMenu(Menu) Activity.onCreateOptionsMenu} 944 * for more information. 945 * 946 * @param menu The options menu in which you place your items. 947 * 948 * @see #setHasOptionsMenu 949 * @see #onPrepareOptionsMenu 950 * @see #onOptionsItemSelected 951 */ 952 public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { 953 } 954 955 /** 956 * Prepare the Screen's standard options menu to be displayed. This is 957 * called right before the menu is shown, every time it is shown. You can 958 * use this method to efficiently enable/disable items or otherwise 959 * dynamically modify the contents. See 960 * {@link Activity#onPrepareOptionsMenu(Menu) Activity.onPrepareOptionsMenu} 961 * for more information. 962 * 963 * @param menu The options menu as last shown or first initialized by 964 * onCreateOptionsMenu(). 965 * 966 * @see #setHasOptionsMenu 967 * @see #onCreateOptionsMenu 968 */ 969 public void onPrepareOptionsMenu(Menu menu) { 970 } 971 972 /** 973 * Called when this fragment's option menu items are no longer being 974 * included in the overall options menu. Receiving this call means that 975 * the menu needed to be rebuilt, but this fragment's items were not 976 * included in the newly built menu (its {@link #onCreateOptionsMenu(Menu, MenuInflater)} 977 * was not called). 978 */ 979 public void onDestroyOptionsMenu() { 980 } 981 982 /** 983 * This hook is called whenever an item in your options menu is selected. 984 * The default implementation simply returns false to have the normal 985 * processing happen (calling the item's Runnable or sending a message to 986 * its Handler as appropriate). You can use this method for any items 987 * for which you would like to do processing without those other 988 * facilities. 989 * 990 * <p>Derived classes should call through to the base class for it to 991 * perform the default menu handling. 992 * 993 * @param item The menu item that was selected. 994 * 995 * @return boolean Return false to allow normal menu processing to 996 * proceed, true to consume it here. 997 * 998 * @see #onCreateOptionsMenu 999 */ 1000 public boolean onOptionsItemSelected(MenuItem item) { 1001 return false; 1002 } 1003 1004 /** 1005 * This hook is called whenever the options menu is being closed (either by the user canceling 1006 * the menu with the back/menu button, or when an item is selected). 1007 * 1008 * @param menu The options menu as last shown or first initialized by 1009 * onCreateOptionsMenu(). 1010 */ 1011 public void onOptionsMenuClosed(Menu menu) { 1012 } 1013 1014 /** 1015 * Called when a context menu for the {@code view} is about to be shown. 1016 * Unlike {@link #onCreateOptionsMenu}, this will be called every 1017 * time the context menu is about to be shown and should be populated for 1018 * the view (or item inside the view for {@link AdapterView} subclasses, 1019 * this can be found in the {@code menuInfo})). 1020 * <p> 1021 * Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an 1022 * item has been selected. 1023 * <p> 1024 * The default implementation calls up to 1025 * {@link Activity#onCreateContextMenu Activity.onCreateContextMenu}, though 1026 * you can not call this implementation if you don't want that behavior. 1027 * <p> 1028 * It is not safe to hold onto the context menu after this method returns. 1029 * {@inheritDoc} 1030 */ 1031 public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { 1032 getActivity().onCreateContextMenu(menu, v, menuInfo); 1033 } 1034 1035 /** 1036 * Registers a context menu to be shown for the given view (multiple views 1037 * can show the context menu). This method will set the 1038 * {@link OnCreateContextMenuListener} on the view to this fragment, so 1039 * {@link #onCreateContextMenu(ContextMenu, View, ContextMenuInfo)} will be 1040 * called when it is time to show the context menu. 1041 * 1042 * @see #unregisterForContextMenu(View) 1043 * @param view The view that should show a context menu. 1044 */ 1045 public void registerForContextMenu(View view) { 1046 view.setOnCreateContextMenuListener(this); 1047 } 1048 1049 /** 1050 * Prevents a context menu to be shown for the given view. This method will 1051 * remove the {@link OnCreateContextMenuListener} on the view. 1052 * 1053 * @see #registerForContextMenu(View) 1054 * @param view The view that should stop showing a context menu. 1055 */ 1056 public void unregisterForContextMenu(View view) { 1057 view.setOnCreateContextMenuListener(null); 1058 } 1059 1060 /** 1061 * This hook is called whenever an item in a context menu is selected. The 1062 * default implementation simply returns false to have the normal processing 1063 * happen (calling the item's Runnable or sending a message to its Handler 1064 * as appropriate). You can use this method for any items for which you 1065 * would like to do processing without those other facilities. 1066 * <p> 1067 * Use {@link MenuItem#getMenuInfo()} to get extra information set by the 1068 * View that added this menu item. 1069 * <p> 1070 * Derived classes should call through to the base class for it to perform 1071 * the default menu handling. 1072 * 1073 * @param item The context menu item that was selected. 1074 * @return boolean Return false to allow normal context menu processing to 1075 * proceed, true to consume it here. 1076 */ 1077 public boolean onContextItemSelected(MenuItem item) { 1078 return false; 1079 } 1080 1081 /** 1082 * Print the Fragments's state into the given stream. 1083 * 1084 * @param prefix Text to print at the front of each line. 1085 * @param fd The raw file descriptor that the dump is being sent to. 1086 * @param writer The PrintWriter to which you should dump your state. This will be 1087 * closed for you after you return. 1088 * @param args additional arguments to the dump request. 1089 */ 1090 public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) { 1091 writer.print(prefix); writer.print("mFragmentId=#"); 1092 writer.print(Integer.toHexString(mFragmentId)); 1093 writer.print(" mContainerId#="); 1094 writer.print(Integer.toHexString(mContainerId)); 1095 writer.print(" mTag="); writer.println(mTag); 1096 writer.print(prefix); writer.print("mState="); writer.print(mState); 1097 writer.print(" mIndex="); writer.print(mIndex); 1098 writer.print(" mWho="); writer.print(mWho); 1099 writer.print(" mBackStackNesting="); writer.println(mBackStackNesting); 1100 writer.print(prefix); writer.print("mAdded="); writer.print(mAdded); 1101 writer.print(" mRemoving="); writer.print(mRemoving); 1102 writer.print(" mResumed="); writer.print(mResumed); 1103 writer.print(" mFromLayout="); writer.print(mFromLayout); 1104 writer.print(" mInLayout="); writer.println(mInLayout); 1105 writer.print(prefix); writer.print("mHidden="); writer.print(mHidden); 1106 writer.print(" mRetainInstance="); writer.print(mRetainInstance); 1107 writer.print(" mRetaining="); writer.print(mRetaining); 1108 writer.print(" mHasMenu="); writer.println(mHasMenu); 1109 if (mFragmentManager != null) { 1110 writer.print(prefix); writer.print("mFragmentManager="); 1111 writer.println(mFragmentManager); 1112 } 1113 if (mImmediateActivity != null) { 1114 writer.print(prefix); writer.print("mImmediateActivity="); 1115 writer.println(mImmediateActivity); 1116 } 1117 if (mActivity != null) { 1118 writer.print(prefix); writer.print("mActivity="); 1119 writer.println(mActivity); 1120 } 1121 if (mArguments != null) { 1122 writer.print(prefix); writer.print("mArguments="); writer.println(mArguments); 1123 } 1124 if (mSavedFragmentState != null) { 1125 writer.print(prefix); writer.print("mSavedFragmentState="); 1126 writer.println(mSavedFragmentState); 1127 } 1128 if (mSavedViewState != null) { 1129 writer.print(prefix); writer.print("mSavedViewState="); 1130 writer.println(mSavedViewState); 1131 } 1132 if (mTarget != null) { 1133 writer.print(prefix); writer.print("mTarget="); writer.print(mTarget); 1134 writer.print(" mTargetRequestCode="); 1135 writer.println(mTargetRequestCode); 1136 } 1137 if (mNextAnim != 0) { 1138 writer.print(prefix); writer.print("mNextAnim="); writer.println(mNextAnim); 1139 } 1140 if (mContainer != null) { 1141 writer.print(prefix); writer.print("mContainer="); writer.println(mContainer); 1142 } 1143 if (mView != null) { 1144 writer.print(prefix); writer.print("mView="); writer.println(mView); 1145 } 1146 if (mInnerView != null) { 1147 writer.print(prefix); writer.print("mInnerView="); writer.println(mView); 1148 } 1149 if (mAnimatingAway != null) { 1150 writer.print(prefix); writer.print("mAnimatingAway="); writer.println(mAnimatingAway); 1151 writer.print(prefix); writer.print("mStateAfterAnimating="); 1152 writer.println(mStateAfterAnimating); 1153 } 1154 if (mLoaderManager != null) { 1155 writer.print(prefix); writer.println("Loader Manager:"); 1156 mLoaderManager.dump(prefix + " ", fd, writer, args); 1157 } 1158 } 1159 1160 void performStop() { 1161 onStop(); 1162 } 1163 1164 void performReallyStop(boolean retaining) { 1165 if (mLoadersStarted) { 1166 mLoadersStarted = false; 1167 if (!mCheckedForLoaderManager) { 1168 mCheckedForLoaderManager = true; 1169 mLoaderManager = mActivity.getLoaderManager(mIndex, mLoadersStarted, false); 1170 } 1171 if (mLoaderManager != null) { 1172 if (!retaining) { 1173 mLoaderManager.doStop(); 1174 } else { 1175 mLoaderManager.doRetain(); 1176 } 1177 } 1178 } 1179 } 1180} 1181