/* * Copyright (C) 2010 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 android.app; import android.animation.Animatable; import android.content.ComponentCallbacks; import android.content.Context; import android.content.Intent; import android.content.res.Configuration; import android.os.Bundle; import android.os.Parcel; import android.os.Parcelable; import android.util.AndroidRuntimeException; import android.util.AttributeSet; import android.util.Log; import android.util.SparseArray; import android.view.ContextMenu; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.view.ContextMenu.ContextMenuInfo; import android.view.View.OnCreateContextMenuListener; import android.widget.AdapterView; import java.util.HashMap; 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 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; 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; mArguments = in.readBundle(); mSavedFragmentState = in.readBundle(); } public Fragment instantiate(Activity activity) { if (mInstance != null) { return mInstance; } mInstance = Fragment.instantiate(activity, mClassName, mArguments); if (mSavedFragmentState != null) { mSavedFragmentState.setClassLoader(activity.getClassLoader()); mInstance.mSavedFragmentState = mSavedFragmentState; } mInstance.setIndex(mIndex); mInstance.mFromLayout = mFromLayout; mInstance.mFragmentId = mFragmentId; mInstance.mContainerId = mContainerId; mInstance.mTag = mTag; mInstance.mRetainInstance = mRetainInstance; 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.writeBundle(mArguments); dest.writeBundle(mSavedFragmentState); } public static final Parcelable.Creator CREATOR = new Parcelable.Creator() { public FragmentState createFromParcel(Parcel in) { return new FragmentState(in); } public FragmentState[] newArray(int size) { return new FragmentState[size]; } }; } /** * A Fragment is a piece of an application's user interface or behavior * that can be placed in an {@link Activity}. */ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener { private static final HashMap> sClassMap = new HashMap>(); 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 STARTED = 3; // Created and started, not resumed. static final int RESUMED = 4; // Created started and resumed. int mState = INITIALIZING; // When instantiated from saved state, this is the saved state. Bundle mSavedFragmentState; SparseArray 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; // Target request code. int mTargetRequestCode; // True if the fragment is in the list of added fragments. boolean mAdded; // 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; // Number of active back stack entries this fragment is in. int mBackStackNesting; // Set as soon as a fragment is added to a transaction (or removed), // to be able to do validation. Activity mImmediateActivity; // Activity this fragment is attached to. Activity mActivity; // 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; // 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; // 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; LoaderManagerImpl mLoaderManager; boolean mStarted; boolean mCheckedForLoaderManager; /** * Thrown by {@link Fragment#instantiate(Context, String, Bundle)} when * there is an instantiation failure. */ static public class InstantiationException extends AndroidRuntimeException { public InstantiationException(String msg, Exception cause) { super(msg, cause); } } /** * Default constructor. Every 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}. * *

The first place where application code should generally run is in * {@link #onAttach(Activity)}, which is the point where the fragment is * actually attached to its activity and thus capable of doing most * retrieve such parameters from the activity in {@link #onAttach(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); } } void restoreViewState() { if (mSavedViewState != null) { mView.restoreHierarchyState(mSavedViewState); mSavedViewState = null; } } void setIndex(int index) { mIndex = index; mWho = "android:fragment:" + mIndex; } void clearIndex() { mIndex = -1; mWho = null; } /** * 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); sb.append("Fragment{"); sb.append(Integer.toHexString(System.identityHashCode(this))); 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; } /** * 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 Activity getActivity() { return mActivity; } /** * Return the FragmentManager for interacting with fragments associated * with this fragment's activity. */ final public FragmentManager getFragmentManager() { return mActivity.mFragments; } /** * Return true if the fragment is currently added to its activity. */ final public boolean isAdded() { return mActivity != null && mActivity.mFragments.mAdded.contains(this); } /** * 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; } /** * 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: *

    *
  • {@link #onDestroy()} will not be called (but {@link #onDetach()} still * will be, because the fragment is being detached from its current activity). *
  • {@link #onCreate(Bundle)} will not be called since the fragment * is not being re-created. *
  • {@link #onAttach(Activity)} and {@link #onActivityCreated(Bundle)} will * still be called. *
*/ public void setRetainInstance(boolean retain) { 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.invalidateOptionsMenu(); } } } /** * Return the LoaderManager for this fragment, creating it if needed. */ public LoaderManager getLoaderManager() { if (mLoaderManager != null) { return mLoaderManager; } mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mIndex, mStarted, true); return mLoaderManager; } /** * Call {@link Activity#startActivity(Intent)} on the fragment's * containing Activity. */ public void startActivity(Intent intent) { mActivity.startActivityFromFragment(this, intent, -1); } /** * Call {@link Activity#startActivityForResult(Intent, int)} on the fragment's * containing Activity. */ public void startActivityForResult(Intent intent, int requestCode) { 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) { } /** * Called when a fragment is being created as part of a view layout * inflation, typically from setting the content view of an activity. This * will be called immediately after the fragment is created from a * tag in a layout file. Note this is before the fragment's * {@link #onAttach(Activity)} has been called; all you should do here is * parse the attributes and save them away. A convenient thing to do is * simply copy them into a Bundle that is given to {@link #setArguments(Bundle)}. * *

This is called every time the fragment is inflated, even if it is * being inflated into a new instance with saved state. Because a fragment's * arguments are retained across instances, it may make no sense to re-parse * the attributes into new arguments. You may want to first check * {@link #getArguments()} and only parse the attributes if it returns null, * the assumption being that if it is non-null those are the same arguments * from the first time the fragment was inflated. (That said, you may want * to have layouts change for different configurations such as landscape * and portrait, which can have different attributes. If so, you will need * to re-parse the attributes each time this is called to generate new * arguments.)

* * @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(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 Animatable onCreateAnimatable(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)}. * *

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)}. * *

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; } 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 #onStart()}. * * @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 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; mStarted = true; if (!mCheckedForLoaderManager) { mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mIndex, mStarted, 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; } 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 * regardless 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(mIndex, mStarted, false); } if (mLoaderManager != null) { mLoaderManager.doDestroy(); } } /** * 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 menu. 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) { } /** * 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. * *

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})). *

* Use {@link #onContextItemSelected(android.view.MenuItem)} to know when an * item has been selected. *

* 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. *

* 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. *

* Use {@link MenuItem#getMenuInfo()} to get extra information set by the * View that added this menu item. *

* 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; } void performStop() { onStop(); if (mStarted) { mStarted = false; if (!mCheckedForLoaderManager) { mCheckedForLoaderManager = true; mLoaderManager = mActivity.getLoaderManager(mIndex, mStarted, false); } if (mLoaderManager != null) { if (mActivity == null || !mActivity.mChangingConfigurations) { mLoaderManager.doStop(); } else { mLoaderManager.doRetain(); } } } } }