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/*
* 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.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.AttributeSet;
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.view.animation.Animation;
import android.widget.AdapterView;
import java.lang.reflect.InvocationTargetException;
import java.util.HashMap;
final class FragmentState implements Parcelable {
static final String VIEW_STATE_TAG = "android:view_state";
final String mClassName;
final int mIndex;
final boolean mFromLayout;
final int mFragmentId;
final int mContainerId;
final String mTag;
final boolean mRetainInstance;
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;
}
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;
mSavedFragmentState = in.readBundle();
}
public Fragment instantiate(Activity activity) {
if (mInstance != null) {
return mInstance;
}
try {
mInstance = Fragment.instantiate(activity, mClassName);
} catch (Exception e) {
throw new RuntimeException("Unable to restore fragment " + mClassName, e);
}
if (mSavedFragmentState != null) {
mSavedFragmentState.setClassLoader(activity.getClassLoader());
mInstance.mSavedFragmentState = mSavedFragmentState;
mInstance.mSavedViewState
= mSavedFragmentState.getSparseParcelableArray(VIEW_STATE_TAG);
}
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(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];
}
};
}
/**
* 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<String, Class<?>> sClassMap =
new HashMap<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 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<Parcelable> mSavedViewState;
// Index into active fragment array.
int mIndex = -1;
// Internal unique name for this fragment;
String mWho;
// 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;
/**
* Default constructor. <strong>Every</string> 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,
* retrieve such parameters from the activity in {@link #onAttach(Activity)}.
*/
public Fragment() {
}
/**
* 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.
* @return Returns a new fragment instance.
* @throws NoSuchMethodException The fragment does not have an empty constructor.
* @throws ClassNotFoundException The fragment class does not exist.
* @throws IllegalArgumentException Bad arguments supplied to fragment class
* constructor (should not happen).
* @throws InstantiationException Caller does not have permission to instantiate
* the fragment (for example its constructor is not public).
* @throws IllegalAccessException Caller does not have permission to access
* the given fragment class.
* @throws InvocationTargetException Failure running the fragment's constructor.
*/
public static Fragment instantiate(Context context, String fname)
throws NoSuchMethodException, ClassNotFoundException,
IllegalArgumentException, InstantiationException,
IllegalAccessException, InvocationTargetException {
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)clazz.newInstance();
}
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;
}
/**
* Return the Activity this fragment is currently associated with.
*/
final public Activity getActivity() {
return mActivity;
}
/**
* 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:
* <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) {
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;
}
mLoaderManager = mActivity.getLoaderManager(mIndex, mStarted);
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 both the first time the fragment is created, as well
* later when it is being re-created from its saved state (which is also
* given here).
*
* XXX This is kind-of yucky... maybe we could just supply the
* AttributeSet to onCreate()?
*
* @param activity The Activity that is inflating the 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;
}
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;
}
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 (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 only
* called if {@link #onCreateView} returns a non-null View.
*/
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;
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 <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) {
}
/**
* 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;
}
void performStop() {
onStop();
if (mStarted) {
mStarted = false;
if (mLoaderManager != null) {
if (mActivity == null || !mActivity.mChangingConfigurations) {
mLoaderManager.doStop();
} else {
mLoaderManager.doRetain();
}
}
}
}
}