Java tutorial
/* * Copyright (C) 2011 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.tencent.tws.assistant.support.v4.app; import java.io.FileDescriptor; import java.io.PrintWriter; import android.app.Activity; import android.content.ComponentCallbacks; import android.content.Context; import android.content.Intent; import android.content.res.Configuration; import android.content.res.Resources; import android.os.Bundle; import android.os.Parcel; import android.os.Parcelable; import android.support.v4.app.FragmentActivity; import android.util.AttributeSet; import android.util.Log; import android.util.SparseArray; import android.view.ContextMenu; import android.view.ContextMenu.ContextMenuInfo; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.View.OnCreateContextMenuListener; import android.view.ViewGroup; import android.view.animation.Animation; import android.widget.AdapterView; import com.tencent.tws.assistant.support.v4.util.DebugUtils; import com.tencent.tws.assistant.support.v4.util.SimpleArrayMap; final class FragmentState implements Parcelable { final String mClassName; final int mIndex; final boolean mFromLayout; final int mFragmentId; final int mContainerId; final String mTag; final boolean mRetainInstance; final boolean mDetached; final Bundle mArguments; Bundle mSavedFragmentState; Fragment mInstance; public FragmentState(Fragment frag) { mClassName = frag.getClass().getName(); mIndex = frag.mIndex; mFromLayout = frag.mFromLayout; mFragmentId = frag.mFragmentId; mContainerId = frag.mContainerId; mTag = frag.mTag; mRetainInstance = frag.mRetainInstance; mDetached = frag.mDetached; mArguments = frag.mArguments; } public FragmentState(Parcel in) { mClassName = in.readString(); mIndex = in.readInt(); mFromLayout = in.readInt() != 0; mFragmentId = in.readInt(); mContainerId = in.readInt(); mTag = in.readString(); mRetainInstance = in.readInt() != 0; mDetached = in.readInt() != 0; mArguments = in.readBundle(); mSavedFragmentState = in.readBundle(); } public Fragment instantiate(TwsFragmentActivity activity, Fragment parent) { if (mInstance != null) { return mInstance; } if (mArguments != null) { mArguments.setClassLoader(activity.getClassLoader()); } mInstance = Fragment.instantiate(activity, mClassName, mArguments); if (mSavedFragmentState != null) { mSavedFragmentState.setClassLoader(activity.getClassLoader()); mInstance.mSavedFragmentState = mSavedFragmentState; } mInstance.setIndex(mIndex, parent); mInstance.mFromLayout = mFromLayout; mInstance.mRestored = true; mInstance.mFragmentId = mFragmentId; mInstance.mContainerId = mContainerId; mInstance.mTag = mTag; mInstance.mRetainInstance = mRetainInstance; mInstance.mDetached = mDetached; mInstance.mFragmentManager = activity.mFragments; if (FragmentManagerImpl.DEBUG) Log.v(FragmentManagerImpl.TAG, "Instantiated fragment " + mInstance); return mInstance; } public int describeContents() { return 0; } public void writeToParcel(Parcel dest, int flags) { dest.writeString(mClassName); dest.writeInt(mIndex); dest.writeInt(mFromLayout ? 1 : 0); dest.writeInt(mFragmentId); dest.writeInt(mContainerId); dest.writeString(mTag); dest.writeInt(mRetainInstance ? 1 : 0); dest.writeInt(mDetached ? 1 : 0); dest.writeBundle(mArguments); dest.writeBundle(mSavedFragmentState); } public static final Parcelable.Creator<FragmentState> CREATOR = new Parcelable.Creator<FragmentState>() { public FragmentState createFromParcel(Parcel in) { return new FragmentState(in); } public FragmentState[] newArray(int size) { return new FragmentState[size]; } }; } /** * Static library support version of the framework's {@link android.app.Fragment}. * Used to write apps that run on platforms prior to Android 3.0. When running * on Android 3.0 or above, this implementation is still used; it does not try * to switch to the framework's implementation. See the framework {@link android.app.Fragment} * documentation for a class overview. * * <p>The main differences when using this support version instead of the framework version are: * <ul> * <li>Your activity must extend {@link FragmentActivity} * <li>You must call {@link FragmentActivity#getSupportFragmentManager} to get the * {@link FragmentManager} * </ul> * */ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener { private static final SimpleArrayMap<String, Class<?>> sClassMap = new SimpleArrayMap<String, Class<?>>(); static final int INITIALIZING = 0; // Not yet created. static final int CREATED = 1; // Created. static final int ACTIVITY_CREATED = 2; // The activity has finished its creation. static final int STOPPED = 3; // Fully created, not started. static final int STARTED = 4; // Created and started, not resumed. static final int RESUMED = 5; // Created started and resumed. int mState = INITIALIZING; // Non-null if the fragment's view hierarchy is currently animating away, // meaning we need to wait a bit on completely destroying it. This is the // view that is animating. View mAnimatingAway; // If mAnimatingAway != null, this is the state we should move to once the // animation is done. int mStateAfterAnimating; // When instantiated from saved state, this is the saved state. Bundle mSavedFragmentState; SparseArray<Parcelable> mSavedViewState; // Index into active fragment array. int mIndex = -1; // Internal unique name for this fragment; String mWho; // Construction arguments; Bundle mArguments; // Target fragment. Fragment mTarget; // For use when retaining a fragment: this is the index of the last mTarget. int mTargetIndex = -1; // Target request code. int mTargetRequestCode; // True if the fragment is in the list of added fragments. boolean mAdded; // If set this fragment is being removed from its activity. boolean mRemoving; // True if the fragment is in the resumed state. boolean mResumed; // Set to true if this fragment was instantiated from a layout file. boolean mFromLayout; // Set to true when the view has actually been inflated in its layout. boolean mInLayout; // True if this fragment has been restored from previously saved state. boolean mRestored; // Number of active back stack entries this fragment is in. int mBackStackNesting; // The fragment manager we are associated with. Set as soon as the // fragment is used in a transaction; cleared after it has been removed // from all transactions. FragmentManagerImpl mFragmentManager; // Activity this fragment is attached to. TwsFragmentActivity mActivity; // Private fragment manager for child fragments inside of this one. FragmentManagerImpl mChildFragmentManager; // If this Fragment is contained in another Fragment, this is that container. Fragment mParentFragment; // The optional identifier for this fragment -- either the container ID if it // was dynamically added to the view hierarchy, or the ID supplied in // layout. int mFragmentId; // When a fragment is being dynamically added to the view hierarchy, this // is the identifier of the parent container it is being added to. int mContainerId; // The optional named tag for this fragment -- usually used to find // fragments that are not part of the layout. String mTag; // Set to true when the app has requested that this fragment be hidden // from the user. boolean mHidden; // Set to true when the app has requested that this fragment be deactivated. boolean mDetached; // If set this fragment would like its instance retained across // configuration changes. boolean mRetainInstance; // If set this fragment is being retained across the current config change. boolean mRetaining; // If set this fragment has menu items to contribute. boolean mHasMenu; // Set to true to allow the fragment's menu to be shown. boolean mMenuVisible = true; // Used to verify that subclasses call through to super class. boolean mCalled; // If app has requested a specific animation, this is the one to use. int mNextAnim; // The parent container of the fragment after dynamically added to UI. ViewGroup mContainer; // The View generated for this fragment. View mView; // The real inner view that will save/restore state. View mInnerView; // Whether this fragment should defer starting until after other fragments // have been started and their loaders are finished. boolean mDeferStart; // Hint provided by the app that this fragment is currently visible to the user. boolean mUserVisibleHint = true; LoaderManagerImpl mLoaderManager; boolean mLoadersStarted; boolean mCheckedForLoaderManager; /** * State information that has been retrieved from a fragment instance * through {@link FragmentManager#saveFragmentInstanceState(Fragment) * FragmentManager.saveFragmentInstanceState}. */ public static class SavedState implements Parcelable { final Bundle mState; SavedState(Bundle state) { mState = state; } SavedState(Parcel in, ClassLoader loader) { mState = in.readBundle(); if (loader != null && mState != null) { mState.setClassLoader(loader); } } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeBundle(mState); } public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() { public SavedState createFromParcel(Parcel in) { return new SavedState(in, null); } public SavedState[] newArray(int size) { return new SavedState[size]; } }; } /** * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when * there is an instantiation failure. */ static public class InstantiationException extends RuntimeException { public InstantiationException(String msg, Exception cause) { super(msg, cause); } } /** * Default constructor. <strong>Every</strong> fragment must have an * empty constructor, so it can be instantiated when restoring its * activity's state. It is strongly recommended that subclasses do not * have other constructors with parameters, since these constructors * will not be called when the fragment is re-instantiated; instead, * arguments can be supplied by the caller with {@link #setArguments} * and later retrieved by the Fragment with {@link #getArguments}. * * <p>Applications should generally not implement a constructor. The * first place application code an run where the fragment is ready to * be used is in {@link #onAttach(Activity)}, the point where the fragment * is actually associated with its activity. Some applications may also * want to implement {@link #onInflate} to retrieve attributes from a * layout resource, though should take care here because this happens for * the fragment is attached to its activity. */ public Fragment() { } /** * Like {@link #instantiate(Context, String, Bundle)} but with a null * argument Bundle. */ public static Fragment instantiate(Context context, String fname) { return instantiate(context, fname, null); } /** * Create a new instance of a Fragment with the given class name. This is * the same as calling its empty constructor. * * @param context The calling context being used to instantiate the fragment. * This is currently just used to get its ClassLoader. * @param fname The class name of the fragment to instantiate. * @param args Bundle of arguments to supply to the fragment, which it * can retrieve with {@link #getArguments()}. May be null. * @return Returns a new fragment instance. * @throws InstantiationException If there is a failure in instantiating * the given fragment class. This is a runtime exception; it is not * normally expected to happen. */ public static Fragment instantiate(Context context, String fname, Bundle args) { try { Class<?> clazz = sClassMap.get(fname); if (clazz == null) { // Class not found in the cache, see if it's real, and try to add it clazz = context.getClassLoader().loadClass(fname); sClassMap.put(fname, clazz); } Fragment f = (Fragment) clazz.newInstance(); if (args != null) { args.setClassLoader(f.getClass().getClassLoader()); f.mArguments = args; } return f; } catch (ClassNotFoundException e) { throw new InstantiationException("Unable to instantiate fragment " + fname + ": make sure class name exists, is public, and has an" + " empty constructor that is public", e); } catch (java.lang.InstantiationException e) { throw new InstantiationException("Unable to instantiate fragment " + fname + ": make sure class name exists, is public, and has an" + " empty constructor that is public", e); } catch (IllegalAccessException e) { throw new InstantiationException("Unable to instantiate fragment " + fname + ": make sure class name exists, is public, and has an" + " empty constructor that is public", e); } } /** * Determine if the given fragment name is a support library fragment class. * * @param context Context used to determine the correct ClassLoader to use * @param fname Class name of the fragment to test * @return true if <code>fname</code> is <code>android.support.v4.app.Fragment</code> * or a subclass, false otherwise. */ static boolean isSupportFragmentClass(Context context, String fname) { try { Class<?> clazz = sClassMap.get(fname); if (clazz == null) { // Class not found in the cache, see if it's real, and try to add it clazz = context.getClassLoader().loadClass(fname); sClassMap.put(fname, clazz); } return Fragment.class.isAssignableFrom(clazz); } catch (ClassNotFoundException e) { return false; } } final void restoreViewState(Bundle savedInstanceState) { if (mSavedViewState != null) { mInnerView.restoreHierarchyState(mSavedViewState); mSavedViewState = null; } mCalled = false; onViewStateRestored(savedInstanceState); if (!mCalled) { throw new SuperNotCalledException( "Fragment " + this + " did not call through to super.onViewStateRestored()"); } } final void setIndex(int index, Fragment parent) { mIndex = index; if (parent != null) { mWho = parent.mWho + ":" + mIndex; } else { mWho = "android:fragment:" + mIndex; } } final boolean isInBackStack() { return mBackStackNesting > 0; } /** * Subclasses can not override equals(). */ @Override final public boolean equals(Object o) { return super.equals(o); } /** * Subclasses can not override hashCode(). */ @Override final public int hashCode() { return super.hashCode(); } @Override public String toString() { StringBuilder sb = new StringBuilder(128); DebugUtils.buildShortClassTag(this, sb); if (mIndex >= 0) { sb.append(" #"); sb.append(mIndex); } if (mFragmentId != 0) { sb.append(" id=0x"); sb.append(Integer.toHexString(mFragmentId)); } if (mTag != null) { sb.append(" "); sb.append(mTag); } sb.append('}'); return sb.toString(); } /** * Return the identifier this fragment is known by. This is either * the android:id value supplied in a layout or the container view ID * supplied when adding the fragment. */ final public int getId() { return mFragmentId; } /** * Get the tag name of the fragment, if specified. */ final public String getTag() { return mTag; } /** * Supply the construction arguments for this fragment. This can only * be called before the fragment has been attached to its activity; that * is, you should call it immediately after constructing the fragment. The * arguments supplied here will be retained across fragment destroy and * creation. */ public void setArguments(Bundle args) { if (mIndex >= 0) { throw new IllegalStateException("Fragment already active"); } mArguments = args; } /** * Return the arguments supplied when the fragment was instantiated, * if any. */ final public Bundle getArguments() { return mArguments; } /** * Set the initial saved state that this Fragment should restore itself * from when first being constructed, as returned by * {@link FragmentManager#saveFragmentInstanceState(Fragment) * FragmentManager.saveFragmentInstanceState}. * * @param state The state the fragment should be restored from. */ public void setInitialSavedState(SavedState state) { if (mIndex >= 0) { throw new IllegalStateException("Fragment already active"); } mSavedFragmentState = state != null && state.mState != null ? state.mState : null; } /** * Optional target for this fragment. This may be used, for example, * if this fragment is being started by another, and when done wants to * give a result back to the first. The target set here is retained * across instances via {@link FragmentManager#putFragment * FragmentManager.putFragment()}. * * @param fragment The fragment that is the target of this one. * @param requestCode Optional request code, for convenience if you * are going to call back with {@link #onActivityResult(int, int, Intent)}. */ public void setTargetFragment(Fragment fragment, int requestCode) { mTarget = fragment; mTargetRequestCode = requestCode; } /** * Return the target fragment set by {@link #setTargetFragment}. */ final public Fragment getTargetFragment() { return mTarget; } /** * Return the target request code set by {@link #setTargetFragment}. */ final public int getTargetRequestCode() { return mTargetRequestCode; } /** * Return the Activity this fragment is currently associated with. */ final public TwsFragmentActivity getActivity() { return mActivity; } /** * Return <code>getActivity().getResources()</code>. */ final public Resources getResources() { if (mActivity == null) { throw new IllegalStateException("Fragment " + this + " not attached to Activity"); } return mActivity.getResources(); } /** * Return a localized, styled CharSequence from the application's package's * default string table. * * @param resId Resource id for the CharSequence text */ public final CharSequence getText(int resId) { return getResources().getText(resId); } /** * Return a localized string from the application's package's * default string table. * * @param resId Resource id for the string */ public final String getString(int resId) { return getResources().getString(resId); } /** * Return a localized formatted string from the application's package's * default string table, substituting the format arguments as defined in * {@link java.util.Formatter} and {@link java.lang.String#format}. * * @param resId Resource id for the format string * @param formatArgs The format arguments that will be used for substitution. */ public final String getString(int resId, Object... formatArgs) { return getResources().getString(resId, formatArgs); } /** * Return the FragmentManager for interacting with fragments associated * with this fragment's activity. Note that this will be non-null slightly * before {@link #getActivity()}, during the time from when the fragment is * placed in a {@link FragmentTransaction} until it is committed and * attached to its activity. * * <p>If this Fragment is a child of another Fragment, the FragmentManager * returned here will be the parent's {@link #getChildFragmentManager()}. */ final public FragmentManager getFragmentManager() { return mFragmentManager; } /** * Return a private FragmentManager for placing and managing Fragments * inside of this Fragment. */ final public FragmentManager getChildFragmentManager() { if (mChildFragmentManager == null) { instantiateChildFragmentManager(); if (mState >= RESUMED) { mChildFragmentManager.dispatchResume(); } else if (mState >= STARTED) { mChildFragmentManager.dispatchStart(); } else if (mState >= ACTIVITY_CREATED) { mChildFragmentManager.dispatchActivityCreated(); } else if (mState >= CREATED) { mChildFragmentManager.dispatchCreate(); } } return mChildFragmentManager; } /** * Returns the parent Fragment containing this Fragment. If this Fragment * is attached directly to an Activity, returns null. */ final public Fragment getParentFragment() { return mParentFragment; } /** * Return true if the fragment is currently added to its activity. */ final public boolean isAdded() { return mActivity != null && mAdded; } /** * Return true if the fragment has been explicitly detached from the UI. * That is, {@link FragmentTransaction#detach(Fragment) * FragmentTransaction.detach(Fragment)} has been used on it. */ final public boolean isDetached() { return mDetached; } /** * Return true if this fragment is currently being removed from its * activity. This is <em>not</em> whether its activity is finishing, but * rather whether it is in the process of being removed from its activity. */ final public boolean isRemoving() { return mRemoving; } /** * Return true if the layout is included as part of an activity view * hierarchy via the <fragment> tag. This will always be true when * fragments are created through the <fragment> tag, <em>except</em> * in the case where an old fragment is restored from a previous state and * it does not appear in the layout of the current state. */ final public boolean isInLayout() { return mInLayout; } /** * Return true if the fragment is in the resumed state. This is true * for the duration of {@link #onResume()} and {@link #onPause()} as well. */ final public boolean isResumed() { return mResumed; } /** * Return true if the fragment is currently visible to the user. This means * it: (1) has been added, (2) has its view attached to the window, and * (3) is not hidden. */ final public boolean isVisible() { return isAdded() && !isHidden() && mView != null && mView.getWindowToken() != null && mView.getVisibility() == View.VISIBLE; } /** * Return true if the fragment has been hidden. By default fragments * are shown. You can find out about changes to this state with * {@link #onHiddenChanged}. Note that the hidden state is orthogonal * to other states -- that is, to be visible to the user, a fragment * must be both started and not hidden. */ final public boolean isHidden() { return mHidden; } /** @hide */ final public boolean hasOptionsMenu() { return mHasMenu; } /** @hide */ final public boolean isMenuVisible() { return mMenuVisible; } /** * Called when the hidden state (as returned by {@link #isHidden()} of * the fragment has changed. Fragments start out not hidden; this will * be called whenever the fragment changes state from that. * @param hidden True if the fragment is now hidden, false if it is not * visible. */ public void onHiddenChanged(boolean hidden) { } /** * Control whether a fragment instance is retained across Activity * re-creation (such as from a configuration change). This can only * be used with fragments not in the back stack. If set, the fragment * lifecycle will be slightly different when an activity is recreated: * <ul> * <li> {@link #onDestroy()} will not be called (but {@link #onDetach()} still * will be, because the fragment is being detached from its current activity). * <li> {@link #onCreate(Bundle)} will not be called since the fragment * is not being re-created. * <li> {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} <b>will</b> * still be called. * </ul> */ public void setRetainInstance(boolean retain) { if (retain && mParentFragment != null) { throw new IllegalStateException("Can't retain fragements that are nested in other fragments"); } mRetainInstance = retain; } final public boolean getRetainInstance() { return mRetainInstance; } /** * Report that this fragment would like to participate in populating * the options menu by receiving a call to {@link #onCreateOptionsMenu} * and related methods. * * @param hasMenu If true, the fragment has menu items to contribute. */ public void setHasOptionsMenu(boolean hasMenu) { if (mHasMenu != hasMenu) { mHasMenu = hasMenu; if (isAdded() && !isHidden()) { mActivity.supportInvalidateOptionsMenu(); } } } /** * Set a hint for whether this fragment's menu should be visible. This * is useful if you know that a fragment has been placed in your view * hierarchy so that the user can not currently seen it, so any menu items * it has should also not be shown. * * @param menuVisible The default is true, meaning the fragment's menu will * be shown as usual. If false, the user will not see the menu. */ public void setMenuVisibility(boolean menuVisible) { if (mMenuVisible != menuVisible) { mMenuVisible = menuVisible; if (mHasMenu && isAdded() && !isHidden()) { mActivity.supportInvalidateOptionsMenu(); } } } /** * Set a hint to the system about whether this fragment's UI is currently visible * to the user. This hint defaults to true and is persistent across fragment instance * state save and restore. * * <p>An app may set this to false to indicate that the fragment's UI is * scrolled out of visibility or is otherwise not directly visible to the user. * This may be used by the system to prioritize operations such as fragment lifecycle updates * or loader ordering behavior.</p> * * @param isVisibleToUser true if this fragment's UI is currently visible to the user (default), * false if it is not. */ public void setUserVisibleHint(boolean isVisibleToUser) { if (!mUserVisibleHint && isVisibleToUser && mState < STARTED) { mFragmentManager.performPendingDeferredStart(this); } mUserVisibleHint = isVisibleToUser; mDeferStart = !isVisibleToUser; } /** * @return The current value of the user-visible hint on this fragment. * @see #setUserVisibleHint(boolean) */ public boolean getUserVisibleHint() { return mUserVisibleHint; } /** * Return the LoaderManager for this fragment, creating it if needed. */ public LoaderManager getLoaderManager() { if (mLoaderManager != null) { return mLoaderManager; } if (mActivity == null) { throw new IllegalStateException("Fragment " + this + " not attached to Activity"); } mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, true); return mLoaderManager; } /** * Call {@link Activity#startActivity(Intent)} on the fragment's * containing Activity. */ public void startActivity(Intent intent) { if (mActivity == null) { throw new IllegalStateException("Fragment " + this + " not attached to Activity"); } mActivity.startActivityFromFragment(this, intent, -1); } /** * Call {@link Activity#startActivityForResult(Intent, int)} on the fragment's * containing Activity. */ public void startActivityForResult(Intent intent, int requestCode) { if (mActivity == null) { throw new IllegalStateException("Fragment " + this + " not attached to Activity"); } mActivity.startActivityFromFragment(this, intent, requestCode); } /** * Receive the result from a previous call to * {@link #startActivityForResult(Intent, int)}. This follows the * related Activity API as described there in * {@link Activity#onActivityResult(int, int, Intent)}. * * @param requestCode The integer request code originally supplied to * startActivityForResult(), allowing you to identify who this * result came from. * @param resultCode The integer result code returned by the child activity * through its setResult(). * @param data An Intent, which can return result data to the caller * (various data can be attached to Intent "extras"). */ public void onActivityResult(int requestCode, int resultCode, Intent data) { } /** * @hide Hack so that DialogFragment can make its Dialog before creating * its views, and the view construction can use the dialog's context for * inflation. Maybe this should become a public API. Note sure. */ public LayoutInflater getLayoutInflater(Bundle savedInstanceState) { return mActivity.getLayoutInflater(); } /** * Called when a fragment is being created as part of a view layout * inflation, typically from setting the content view of an activity. This * may be called immediately after the fragment is created from a <fragment> * tag in a layout file. Note this is <em>before</em> the fragment's * {@link #onAttach(Activity)} has been called; all you should do here is * parse the attributes and save them away. * * <p>This is called every time the fragment is inflated, even if it is * being inflated into a new instance with saved state. It typically makes * sense to re-parse the parameters each time, to allow them to change with * different configurations.</p> * * <p>Here is a typical implementation of a fragment that can take parameters * both through attributes supplied here as well from {@link #getArguments()}:</p> * * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java * fragment} * * <p>Note that parsing the XML attributes uses a "styleable" resource. The * declaration for the styleable used here is:</p> * * {@sample development/samples/ApiDemos/res/values/attrs.xml fragment_arguments} * * <p>The fragment can then be declared within its activity's content layout * through a tag like this:</p> * * {@sample development/samples/ApiDemos/res/layout/fragment_arguments.xml from_attributes} * * <p>This fragment can also be created dynamically from arguments given * at runtime in the arguments Bundle; here is an example of doing so at * creation of the containing activity:</p> * * {@sample development/samples/ApiDemos/src/com/example/android/apis/app/FragmentArguments.java * create} * * @param activity The Activity that is inflating this fragment. * @param attrs The attributes at the tag where the fragment is * being created. * @param savedInstanceState If the fragment is being re-created from * a previous saved state, this is the state. */ public void onInflate(Activity activity, AttributeSet attrs, Bundle savedInstanceState) { mCalled = true; } /** * Called when a fragment is first attached to its activity. * {@link #onCreate(Bundle)} will be called after this. */ public void onAttach(Activity activity) { mCalled = true; } /** * Called when a fragment loads an animation. */ public Animation onCreateAnimation(int transit, boolean enter, int nextAnim) { return null; } /** * Called to do initial creation of a fragment. This is called after * {@link #onAttach(Activity)} and before * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. * * <p>Note that this can be called while the fragment's activity is * still in the process of being created. As such, you can not rely * on things like the activity's content view hierarchy being initialized * at this point. If you want to do work once the activity itself is * created, see {@link #onActivityCreated(Bundle)}. * * @param savedInstanceState If the fragment is being re-created from * a previous saved state, this is the state. */ public void onCreate(Bundle savedInstanceState) { mCalled = true; } /** * Called to have the fragment instantiate its user interface view. * This is optional, and non-graphical fragments can return null (which * is the default implementation). This will be called between * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}. * * <p>If you return a View from here, you will later be called in * {@link #onDestroyView} when the view is being released. * * @param inflater The LayoutInflater object that can be used to inflate * any views in the fragment, * @param container If non-null, this is the parent view that the fragment's * UI should be attached to. The fragment should not add the view itself, * but this can be used to generate the LayoutParams of the view. * @param savedInstanceState If non-null, this fragment is being re-constructed * from a previous saved state as given here. * * @return Return the View for the fragment's UI, or null. */ public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { return null; } /** * Called immediately after {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)} * has returned, but before any saved state has been restored in to the view. * This gives subclasses a chance to initialize themselves once * they know their view hierarchy has been completely created. The fragment's * view hierarchy is not however attached to its parent at this point. * @param view The View returned by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}. * @param savedInstanceState If non-null, this fragment is being re-constructed * from a previous saved state as given here. */ public void onViewCreated(View view, Bundle savedInstanceState) { } /** * Get the root view for the fragment's layout (the one returned by {@link #onCreateView}), * if provided. * * @return The fragment's root view, or null if it has no layout. */ public View getView() { return mView; } /** * Called when the fragment's activity has been created and this * fragment's view hierarchy instantiated. It can be used to do final * initialization once these pieces are in place, such as retrieving * views or restoring state. It is also useful for fragments that use * {@link #setRetainInstance(boolean)} to retain their instance, * as this callback tells the fragment when it is fully associated with * the new activity instance. This is called after {@link #onCreateView} * and before {@link #onViewStateRestored(Bundle)}. * * @param savedInstanceState If the fragment is being re-created from * a previous saved state, this is the state. */ public void onActivityCreated(Bundle savedInstanceState) { mCalled = true; } /** * Called when all saved state has been restored into the view hierarchy * of the fragment. This can be used to do initialization based on saved * state that you are letting the view hierarchy track itself, such as * whether check box widgets are currently checked. This is called * after {@link #onActivityCreated(Bundle)} and before * {@link #onStart()}. * * @param savedInstanceState If the fragment is being re-created from * a previous saved state, this is the state. */ public void onViewStateRestored(Bundle savedInstanceState) { mCalled = true; } /** * Called when the Fragment is visible to the user. This is generally * tied to {@link Activity#onStart() Activity.onStart} of the containing * Activity's lifecycle. */ public void onStart() { mCalled = true; if (!mLoadersStarted) { mLoadersStarted = true; if (!mCheckedForLoaderManager) { mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, false); } if (mLoaderManager != null) { mLoaderManager.doStart(); } } } /** * Called when the fragment is visible to the user and actively running. * This is generally * tied to {@link Activity#onResume() Activity.onResume} of the containing * Activity's lifecycle. */ public void onResume() { mCalled = true; } /** * Called to ask the fragment to save its current dynamic state, so it * can later be reconstructed in a new instance of its process is * restarted. If a new instance of the fragment later needs to be * created, the data you place in the Bundle here will be available * in the Bundle given to {@link #onCreate(Bundle)}, * {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}, and * {@link #onActivityCreated(Bundle)}. * * <p>This corresponds to {@link Activity#onSaveInstanceState(Bundle) * Activity.onSaveInstanceState(Bundle)} and most of the discussion there * applies here as well. Note however: <em>this method may be called * at any time before {@link #onDestroy()}</em>. There are many situations * where a fragment may be mostly torn down (such as when placed on the * back stack with no UI showing), but its state will not be saved until * its owning activity actually needs to save its state. * * @param outState Bundle in which to place your saved state. */ public void onSaveInstanceState(Bundle outState) { } public void onConfigurationChanged(Configuration newConfig) { mCalled = true; } /** * Called when the Fragment is no longer resumed. This is generally * tied to {@link Activity#onPause() Activity.onPause} of the containing * Activity's lifecycle. */ public void onPause() { mCalled = true; } /** * Called when the Fragment is no longer started. This is generally * tied to {@link Activity#onStop() Activity.onStop} of the containing * Activity's lifecycle. */ public void onStop() { mCalled = true; } public void onLowMemory() { mCalled = true; } /** * Called when the view previously created by {@link #onCreateView} has * been detached from the fragment. The next time the fragment needs * to be displayed, a new view will be created. This is called * after {@link #onStop()} and before {@link #onDestroy()}. It is called * <em>regardless</em> of whether {@link #onCreateView} returned a * non-null view. Internally it is called after the view's state has * been saved but before it has been removed from its parent. */ public void onDestroyView() { mCalled = true; } /** * Called when the fragment is no longer in use. This is called * after {@link #onStop()} and before {@link #onDetach()}. */ public void onDestroy() { mCalled = true; //Log.v("foo", "onDestroy: mCheckedForLoaderManager=" + mCheckedForLoaderManager // + " mLoaderManager=" + mLoaderManager); if (!mCheckedForLoaderManager) { mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, false); } if (mLoaderManager != null) { mLoaderManager.doDestroy(); } } /** * Called by the fragment manager once this fragment has been removed, * so that we don't have any left-over state if the application decides * to re-use the instance. This only clears state that the framework * internally manages, not things the application sets. */ void initState() { mIndex = -1; mWho = null; mAdded = false; mRemoving = false; mResumed = false; mFromLayout = false; mInLayout = false; mRestored = false; mBackStackNesting = 0; mFragmentManager = null; mActivity = null; mFragmentId = 0; mContainerId = 0; mTag = null; mHidden = false; mDetached = false; mRetaining = false; mLoaderManager = null; mLoadersStarted = false; mCheckedForLoaderManager = false; } /** * Called when the fragment is no longer attached to its activity. This * is called after {@link #onDestroy()}. */ public void onDetach() { mCalled = true; } /** * Initialize the contents of the Activity's standard options menu. You * should place your menu items in to <var>menu</var>. For this method * to be called, you must have first called {@link #setHasOptionsMenu}. See * {@link Activity#onCreateOptionsMenu(Menu) Activity.onCreateOptionsMenu} * for more information. * * @param menu The options menu in which you place your items. * * @see #setHasOptionsMenu * @see #onPrepareOptionsMenu * @see #onOptionsItemSelected */ public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { } /** * Prepare the Screen's standard options menu to be displayed. This is * called right before the menu is shown, every time it is shown. You can * use this method to efficiently enable/disable items or otherwise * dynamically modify the contents. See * {@link Activity#onPrepareOptionsMenu(Menu) Activity.onPrepareOptionsMenu} * for more information. * * @param menu The options menu as last shown or first initialized by * onCreateOptionsMenu(). * * @see #setHasOptionsMenu * @see #onCreateOptionsMenu */ public void onPrepareOptionsMenu(Menu menu) { } /** * Called when this fragment's option menu items are no longer being * included in the overall options menu. Receiving this call means that * the menu needed to be rebuilt, but this fragment's items were not * included in the newly built menu (its {@link #onCreateOptionsMenu(Menu, MenuInflater)} * was not called). */ public void onDestroyOptionsMenu() { } /** * This hook is called whenever an item in your options menu is selected. * The default implementation simply returns false to have the normal * processing happen (calling the item's Runnable or sending a message to * its Handler as appropriate). You can use this method for any items * for which you would like to do processing without those other * facilities. * * <p>Derived classes should call through to the base class for it to * perform the default menu handling. * * @param item The menu item that was selected. * * @return boolean Return false to allow normal menu processing to * proceed, true to consume it here. * * @see #onCreateOptionsMenu */ public boolean onOptionsItemSelected(MenuItem item) { return false; } /** * This hook is called whenever the options menu is being closed (either by the user canceling * the menu with the back/menu button, or when an item is selected). * * @param menu The options menu as last shown or first initialized by * onCreateOptionsMenu(). */ public void onOptionsMenuClosed(Menu menu) { } /** * Called when a context menu for the {@code view} is about to be shown. * Unlike {@link #onCreateOptionsMenu}, this will be called every * time the context menu is about to be shown and should be populated for * the view (or item inside the view for {@link AdapterView} subclasses, * this can be found in the {@code menuInfo})). * <p> * Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an * item has been selected. * <p> * The default implementation calls up to * {@link Activity#onCreateContextMenu Activity.onCreateContextMenu}, though * you can not call this implementation if you don't want that behavior. * <p> * It is not safe to hold onto the context menu after this method returns. * {@inheritDoc} */ public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { getActivity().onCreateContextMenu(menu, v, menuInfo); } /** * Registers a context menu to be shown for the given view (multiple views * can show the context menu). This method will set the * {@link OnCreateContextMenuListener} on the view to this fragment, so * {@link #onCreateContextMenu(ContextMenu, View, ContextMenuInfo)} will be * called when it is time to show the context menu. * * @see #unregisterForContextMenu(View) * @param view The view that should show a context menu. */ public void registerForContextMenu(View view) { view.setOnCreateContextMenuListener(this); } /** * Prevents a context menu to be shown for the given view. This method will * remove the {@link OnCreateContextMenuListener} on the view. * * @see #registerForContextMenu(View) * @param view The view that should stop showing a context menu. */ public void unregisterForContextMenu(View view) { view.setOnCreateContextMenuListener(null); } /** * This hook is called whenever an item in a context menu is selected. The * default implementation simply returns false to have the normal processing * happen (calling the item's Runnable or sending a message to its Handler * as appropriate). You can use this method for any items for which you * would like to do processing without those other facilities. * <p> * Use {@link MenuItem#getMenuInfo()} to get extra information set by the * View that added this menu item. * <p> * Derived classes should call through to the base class for it to perform * the default menu handling. * * @param item The context menu item that was selected. * @return boolean Return false to allow normal context menu processing to * proceed, true to consume it here. */ public boolean onContextItemSelected(MenuItem item) { return false; } /** * Print the Fragments's state into the given stream. * * @param prefix Text to print at the front of each line. * @param fd The raw file descriptor that the dump is being sent to. * @param writer The PrintWriter to which you should dump your state. This will be * closed for you after you return. * @param args additional arguments to the dump request. */ public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) { writer.print(prefix); writer.print("mFragmentId=#"); writer.print(Integer.toHexString(mFragmentId)); writer.print(" mContainerId=#"); writer.print(Integer.toHexString(mContainerId)); writer.print(" mTag="); writer.println(mTag); writer.print(prefix); writer.print("mState="); writer.print(mState); writer.print(" mIndex="); writer.print(mIndex); writer.print(" mWho="); writer.print(mWho); writer.print(" mBackStackNesting="); writer.println(mBackStackNesting); writer.print(prefix); writer.print("mAdded="); writer.print(mAdded); writer.print(" mRemoving="); writer.print(mRemoving); writer.print(" mResumed="); writer.print(mResumed); writer.print(" mFromLayout="); writer.print(mFromLayout); writer.print(" mInLayout="); writer.println(mInLayout); writer.print(prefix); writer.print("mHidden="); writer.print(mHidden); writer.print(" mDetached="); writer.print(mDetached); writer.print(" mMenuVisible="); writer.print(mMenuVisible); writer.print(" mHasMenu="); writer.println(mHasMenu); writer.print(prefix); writer.print("mRetainInstance="); writer.print(mRetainInstance); writer.print(" mRetaining="); writer.print(mRetaining); writer.print(" mUserVisibleHint="); writer.println(mUserVisibleHint); if (mFragmentManager != null) { writer.print(prefix); writer.print("mFragmentManager="); writer.println(mFragmentManager); } if (mActivity != null) { writer.print(prefix); writer.print("mActivity="); writer.println(mActivity); } if (mParentFragment != null) { writer.print(prefix); writer.print("mParentFragment="); writer.println(mParentFragment); } if (mArguments != null) { writer.print(prefix); writer.print("mArguments="); writer.println(mArguments); } if (mSavedFragmentState != null) { writer.print(prefix); writer.print("mSavedFragmentState="); writer.println(mSavedFragmentState); } if (mSavedViewState != null) { writer.print(prefix); writer.print("mSavedViewState="); writer.println(mSavedViewState); } if (mTarget != null) { writer.print(prefix); writer.print("mTarget="); writer.print(mTarget); writer.print(" mTargetRequestCode="); writer.println(mTargetRequestCode); } if (mNextAnim != 0) { writer.print(prefix); writer.print("mNextAnim="); writer.println(mNextAnim); } if (mContainer != null) { writer.print(prefix); writer.print("mContainer="); writer.println(mContainer); } if (mView != null) { writer.print(prefix); writer.print("mView="); writer.println(mView); } if (mInnerView != null) { writer.print(prefix); writer.print("mInnerView="); writer.println(mView); } if (mAnimatingAway != null) { writer.print(prefix); writer.print("mAnimatingAway="); writer.println(mAnimatingAway); writer.print(prefix); writer.print("mStateAfterAnimating="); writer.println(mStateAfterAnimating); } if (mLoaderManager != null) { writer.print(prefix); writer.println("Loader Manager:"); mLoaderManager.dump(prefix + " ", fd, writer, args); } if (mChildFragmentManager != null) { writer.print(prefix); writer.println("Child " + mChildFragmentManager + ":"); mChildFragmentManager.dump(prefix + " ", fd, writer, args); } } Fragment findFragmentByWho(String who) { if (who.equals(mWho)) { return this; } if (mChildFragmentManager != null) { return mChildFragmentManager.findFragmentByWho(who); } return null; } void instantiateChildFragmentManager() { mChildFragmentManager = new FragmentManagerImpl(); mChildFragmentManager.attachActivity(mActivity, new FragmentContainer() { @Override public View findViewById(int id) { if (mView == null) { throw new IllegalStateException("Fragment does not have a view"); } return mView.findViewById(id); } }, this); } void performCreate(Bundle savedInstanceState) { if (mChildFragmentManager != null) { mChildFragmentManager.noteStateNotSaved(); } mCalled = false; onCreate(savedInstanceState); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onCreate()"); } if (savedInstanceState != null) { Parcelable p = savedInstanceState.getParcelable(TwsFragmentActivity.FRAGMENTS_TAG); if (p != null) { if (mChildFragmentManager == null) { instantiateChildFragmentManager(); } mChildFragmentManager.restoreAllState(p, null); mChildFragmentManager.dispatchCreate(); } } } View performCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { if (mChildFragmentManager != null) { mChildFragmentManager.noteStateNotSaved(); } return onCreateView(inflater, container, savedInstanceState); } void performActivityCreated(Bundle savedInstanceState) { if (mChildFragmentManager != null) { mChildFragmentManager.noteStateNotSaved(); } mCalled = false; onActivityCreated(savedInstanceState); if (!mCalled) { throw new SuperNotCalledException( "Fragment " + this + " did not call through to super.onActivityCreated()"); } if (mChildFragmentManager != null) { mChildFragmentManager.dispatchActivityCreated(); } } void performStart() { if (mChildFragmentManager != null) { mChildFragmentManager.noteStateNotSaved(); mChildFragmentManager.execPendingActions(); } mCalled = false; onStart(); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onStart()"); } if (mChildFragmentManager != null) { mChildFragmentManager.dispatchStart(); } if (mLoaderManager != null) { mLoaderManager.doReportStart(); } } void performResume() { if (mChildFragmentManager != null) { mChildFragmentManager.noteStateNotSaved(); mChildFragmentManager.execPendingActions(); } mCalled = false; onResume(); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onResume()"); } if (mChildFragmentManager != null) { mChildFragmentManager.dispatchResume(); mChildFragmentManager.execPendingActions(); } } void performConfigurationChanged(Configuration newConfig) { onConfigurationChanged(newConfig); if (mChildFragmentManager != null) { mChildFragmentManager.dispatchConfigurationChanged(newConfig); } } void performLowMemory() { onLowMemory(); if (mChildFragmentManager != null) { mChildFragmentManager.dispatchLowMemory(); } } /* void performTrimMemory(int level) { onTrimMemory(level); if (mChildFragmentManager != null) { mChildFragmentManager.dispatchTrimMemory(level); } } */ boolean performCreateOptionsMenu(Menu menu, MenuInflater inflater) { boolean show = false; if (!mHidden) { if (mHasMenu && mMenuVisible) { show = true; onCreateOptionsMenu(menu, inflater); } if (mChildFragmentManager != null) { show |= mChildFragmentManager.dispatchCreateOptionsMenu(menu, inflater); } } return show; } boolean performPrepareOptionsMenu(Menu menu) { boolean show = false; if (!mHidden) { if (mHasMenu && mMenuVisible) { show = true; onPrepareOptionsMenu(menu); } if (mChildFragmentManager != null) { show |= mChildFragmentManager.dispatchPrepareOptionsMenu(menu); } } return show; } boolean performOptionsItemSelected(MenuItem item) { if (!mHidden) { if (mHasMenu && mMenuVisible) { if (onOptionsItemSelected(item)) { return true; } } if (mChildFragmentManager != null) { if (mChildFragmentManager.dispatchOptionsItemSelected(item)) { return true; } } } return false; } boolean performContextItemSelected(MenuItem item) { if (!mHidden) { if (onContextItemSelected(item)) { return true; } if (mChildFragmentManager != null) { if (mChildFragmentManager.dispatchContextItemSelected(item)) { return true; } } } return false; } void performOptionsMenuClosed(Menu menu) { if (!mHidden) { if (mHasMenu && mMenuVisible) { onOptionsMenuClosed(menu); } if (mChildFragmentManager != null) { mChildFragmentManager.dispatchOptionsMenuClosed(menu); } } } void performSaveInstanceState(Bundle outState) { onSaveInstanceState(outState); if (mChildFragmentManager != null) { Parcelable p = mChildFragmentManager.saveAllState(); if (p != null) { outState.putParcelable(TwsFragmentActivity.FRAGMENTS_TAG, p); } } } void performPause() { if (mChildFragmentManager != null) { mChildFragmentManager.dispatchPause(); } mCalled = false; onPause(); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onPause()"); } } void performStop() { if (mChildFragmentManager != null) { mChildFragmentManager.dispatchStop(); } mCalled = false; onStop(); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onStop()"); } } void performReallyStop() { if (mChildFragmentManager != null) { mChildFragmentManager.dispatchReallyStop(); } if (mLoadersStarted) { mLoadersStarted = false; if (!mCheckedForLoaderManager) { mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mWho, mLoadersStarted, false); } if (mLoaderManager != null) { if (!mActivity.mRetaining) { mLoaderManager.doStop(); } else { mLoaderManager.doRetain(); } } } } void performDestroyView() { if (mChildFragmentManager != null) { mChildFragmentManager.dispatchDestroyView(); } mCalled = false; onDestroyView(); if (!mCalled) { throw new SuperNotCalledException( "Fragment " + this + " did not call through to super.onDestroyView()"); } if (mLoaderManager != null) { mLoaderManager.doReportNextStart(); } } void performDestroy() { if (mChildFragmentManager != null) { mChildFragmentManager.dispatchDestroy(); } mCalled = false; onDestroy(); if (!mCalled) { throw new SuperNotCalledException("Fragment " + this + " did not call through to super.onDestroy()"); } } public void acceptExtras(int extras) { } }