Java tutorial
/* * Copyright (C) 2012 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.support.v7.app; import android.app.Activity; import android.content.Intent; import android.content.res.Configuration; import android.os.Build; import android.os.Bundle; import android.support.v4.app.ActionBarDrawerToggle; import android.support.v4.app.ActivityCompat; import android.support.v4.app.FragmentActivity; import android.support.v4.app.NavUtils; import android.support.v4.app.TaskStackBuilder; import android.support.v4.view.WindowCompat; import android.support.v7.view.ActionMode; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.view.Window; /** * Base class for activities that use the support library action bar features. */ public class ActionBarActivity extends FragmentActivity implements ActionBar.Callback, TaskStackBuilder.SupportParentable, ActionBarDrawerToggle.DelegateProvider { ActionBarActivityDelegate mImpl; /** * Support library version of {@link Activity#getActionBar}. * * <p>Retrieve a reference to this activity's ActionBar. * * @return The Activity's ActionBar, or null if it does not have one. */ public ActionBar getSupportActionBar() { return mImpl.getSupportActionBar(); } @Override public MenuInflater getMenuInflater() { return mImpl.getMenuInflater(); } @Override public void setContentView(int layoutResID) { mImpl.setContentView(layoutResID); } @Override public void setContentView(View view) { mImpl.setContentView(view); } @Override public void setContentView(View view, ViewGroup.LayoutParams params) { mImpl.setContentView(view, params); } @Override public void addContentView(View view, ViewGroup.LayoutParams params) { mImpl.addContentView(view, params); } @Override protected void onCreate(Bundle savedInstanceState) { mImpl = ActionBarActivityDelegate.createDelegate(this); super.onCreate(savedInstanceState); mImpl.onCreate(savedInstanceState); } @Override public void onConfigurationChanged(Configuration newConfig) { super.onConfigurationChanged(newConfig); mImpl.onConfigurationChanged(newConfig); } @Override protected void onStop() { super.onStop(); mImpl.onStop(); } @Override protected void onPostResume() { super.onPostResume(); mImpl.onPostResume(); } @Override public View onCreatePanelView(int featureId) { if (featureId == Window.FEATURE_OPTIONS_PANEL) { return mImpl.onCreatePanelView(featureId); } else { return super.onCreatePanelView(featureId); } } @Override public final boolean onMenuItemSelected(int featureId, android.view.MenuItem item) { if (mImpl.onMenuItemSelected(featureId, item)) { return true; } final ActionBar ab = getSupportActionBar(); if (item.getItemId() == android.R.id.home && ab != null && (ab.getDisplayOptions() & ActionBar.DISPLAY_HOME_AS_UP) != 0) { return onSupportNavigateUp(); } return false; } @Override protected void onTitleChanged(CharSequence title, int color) { super.onTitleChanged(title, color); mImpl.onTitleChanged(title); } /** * Enable extended support library window features. * <p> * This is a convenience for calling * {@link android.view.Window#requestFeature getWindow().requestFeature()}. * </p> * * @param featureId The desired feature as defined in * {@link android.view.Window} or {@link WindowCompat}. * @return Returns true if the requested feature is supported and now enabled. * * @see android.app.Activity#requestWindowFeature * @see android.view.Window#requestFeature */ public boolean supportRequestWindowFeature(int featureId) { return mImpl.supportRequestWindowFeature(featureId); } @Override public void supportInvalidateOptionsMenu() { // Only call up to super on ICS+ if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) { super.supportInvalidateOptionsMenu(); } mImpl.supportInvalidateOptionsMenu(); } /** * Notifies the Activity that a support action mode has been started. * Activity subclasses overriding this method should call the superclass implementation. * * @param mode The new action mode. */ public void onSupportActionModeStarted(ActionMode mode) { } /** * Notifies the activity that a support action mode has finished. * Activity subclasses overriding this method should call the superclass implementation. * * @param mode The action mode that just finished. */ public void onSupportActionModeFinished(ActionMode mode) { } public ActionMode startSupportActionMode(ActionMode.Callback callback) { return mImpl.startSupportActionMode(callback); } @Override public boolean onCreatePanelMenu(int featureId, Menu menu) { return mImpl.onCreatePanelMenu(featureId, menu); } @Override public boolean onPreparePanel(int featureId, View view, Menu menu) { return mImpl.onPreparePanel(featureId, view, menu); } void superSetContentView(int resId) { super.setContentView(resId); } void superSetContentView(View v) { super.setContentView(v); } void superSetContentView(View v, ViewGroup.LayoutParams lp) { super.setContentView(v, lp); } void superAddContentView(View v, ViewGroup.LayoutParams lp) { super.addContentView(v, lp); } boolean superOnCreatePanelMenu(int featureId, android.view.Menu frameworkMenu) { return super.onCreatePanelMenu(featureId, frameworkMenu); } boolean superOnPreparePanel(int featureId, View view, android.view.Menu menu) { return super.onPreparePanel(featureId, view, menu); } boolean superOnMenuItemSelected(int featureId, MenuItem menuItem) { return super.onMenuItemSelected(featureId, menuItem); } @Override public void onBackPressed() { if (!mImpl.onBackPressed()) { super.onBackPressed(); } } /** * Support library version of {@link Activity#setProgressBarVisibility(boolean)} * <p> * Sets the visibility of the progress bar in the title. * <p> * In order for the progress bar to be shown, the feature must be requested * via {@link #supportRequestWindowFeature(int)}. * * @param visible Whether to show the progress bars in the title. */ public void setSupportProgressBarVisibility(boolean visible) { mImpl.setSupportProgressBarVisibility(visible); } /** * Support library version of {@link Activity#setProgressBarIndeterminateVisibility(boolean)} * <p> * Sets the visibility of the indeterminate progress bar in the title. * <p> * In order for the progress bar to be shown, the feature must be requested * via {@link #supportRequestWindowFeature(int)}. * * @param visible Whether to show the progress bars in the title. */ public void setSupportProgressBarIndeterminateVisibility(boolean visible) { mImpl.setSupportProgressBarIndeterminateVisibility(visible); } /** * Support library version of {@link Activity#setProgressBarIndeterminate(boolean)} * <p> * Sets whether the horizontal progress bar in the title should be indeterminate (the * circular is always indeterminate). * <p> * In order for the progress bar to be shown, the feature must be requested * via {@link #supportRequestWindowFeature(int)}. * * @param indeterminate Whether the horizontal progress bar should be indeterminate. */ public void setSupportProgressBarIndeterminate(boolean indeterminate) { mImpl.setSupportProgressBarIndeterminate(indeterminate); } /** * Support library version of {@link Activity#setProgress(int)}. * <p> * Sets the progress for the progress bars in the title. * <p> * In order for the progress bar to be shown, the feature must be requested * via {@link #supportRequestWindowFeature(int)}. * * @param progress The progress for the progress bar. Valid ranges are from * 0 to 10000 (both inclusive). If 10000 is given, the progress * bar will be completely filled and will fade out. */ public void setSupportProgress(int progress) { mImpl.setSupportProgress(progress); } /** * Support version of {@link #onCreateNavigateUpTaskStack(android.app.TaskStackBuilder)}. * This method will be called on all platform versions. * * Define the synthetic task stack that will be generated during Up navigation from * a different task. * * <p>The default implementation of this method adds the parent chain of this activity * as specified in the manifest to the supplied {@link TaskStackBuilder}. Applications * may choose to override this method to construct the desired task stack in a different * way.</p> * * <p>This method will be invoked by the default implementation of {@link #onNavigateUp()} * if {@link #shouldUpRecreateTask(Intent)} returns true when supplied with the intent * returned by {@link #getParentActivityIntent()}.</p> * * <p>Applications that wish to supply extra Intent parameters to the parent stack defined * by the manifest should override * {@link #onPrepareSupportNavigateUpTaskStack(TaskStackBuilder)}.</p> * * @param builder An empty TaskStackBuilder - the application should add intents representing * the desired task stack */ public void onCreateSupportNavigateUpTaskStack(TaskStackBuilder builder) { builder.addParentStack(this); } /** * Support version of {@link #onPrepareNavigateUpTaskStack(android.app.TaskStackBuilder)}. * This method will be called on all platform versions. * * Prepare the synthetic task stack that will be generated during Up navigation * from a different task. * * <p>This method receives the {@link TaskStackBuilder} with the constructed series of * Intents as generated by {@link #onCreateSupportNavigateUpTaskStack(TaskStackBuilder)}. * If any extra data should be added to these intents before launching the new task, * the application should override this method and add that data here.</p> * * @param builder A TaskStackBuilder that has been populated with Intents by * onCreateNavigateUpTaskStack. */ public void onPrepareSupportNavigateUpTaskStack(TaskStackBuilder builder) { } /** * This method is called whenever the user chooses to navigate Up within your application's * activity hierarchy from the action bar. * * <p>If a parent was specified in the manifest for this activity or an activity-alias to it, * default Up navigation will be handled automatically. See * {@link #getSupportParentActivityIntent()} for how to specify the parent. If any activity * along the parent chain requires extra Intent arguments, the Activity subclass * should override the method {@link #onPrepareSupportNavigateUpTaskStack(TaskStackBuilder)} * to supply those arguments.</p> * * <p>See <a href="{@docRoot}guide/topics/fundamentals/tasks-and-back-stack.html">Tasks and * Back Stack</a> from the developer guide and * <a href="{@docRoot}design/patterns/navigation.html">Navigation</a> from the design guide * for more information about navigating within your app.</p> * * <p>See the {@link TaskStackBuilder} class and the Activity methods * {@link #getSupportParentActivityIntent()}, {@link #supportShouldUpRecreateTask(Intent)}, and * {@link #supportNavigateUpTo(Intent)} for help implementing custom Up navigation.</p> * * @return true if Up navigation completed successfully and this Activity was finished, * false otherwise. */ public boolean onSupportNavigateUp() { Intent upIntent = getSupportParentActivityIntent(); if (upIntent != null) { if (supportShouldUpRecreateTask(upIntent)) { TaskStackBuilder b = TaskStackBuilder.create(this); onCreateSupportNavigateUpTaskStack(b); onPrepareSupportNavigateUpTaskStack(b); b.startActivities(); try { ActivityCompat.finishAffinity(this); } catch (IllegalStateException e) { // This can only happen on 4.1+, when we don't have a parent or a result set. // In that case we should just finish(). finish(); } } else { // This activity is part of the application's task, so simply // navigate up to the hierarchical parent activity. supportNavigateUpTo(upIntent); } return true; } return false; } /** * Obtain an {@link Intent} that will launch an explicit target activity * specified by sourceActivity's {@link NavUtils#PARENT_ACTIVITY} <meta-data> * element in the application's manifest. If the device is running * Jellybean or newer, the android:parentActivityName attribute will be preferred * if it is present. * * @return a new Intent targeting the defined parent activity of sourceActivity */ public Intent getSupportParentActivityIntent() { return NavUtils.getParentActivityIntent(this); } /** * Returns true if sourceActivity should recreate the task when navigating 'up' * by using targetIntent. * * <p>If this method returns false the app can trivially call * {@link #supportNavigateUpTo(Intent)} using the same parameters to correctly perform * up navigation. If this method returns false, the app should synthesize a new task stack * by using {@link TaskStackBuilder} or another similar mechanism to perform up navigation.</p> * * @param targetIntent An intent representing the target destination for up navigation * @return true if navigating up should recreate a new task stack, false if the same task * should be used for the destination */ public boolean supportShouldUpRecreateTask(Intent targetIntent) { return NavUtils.shouldUpRecreateTask(this, targetIntent); } /** * Navigate from sourceActivity to the activity specified by upIntent, finishing sourceActivity * in the process. upIntent will have the flag {@link Intent#FLAG_ACTIVITY_CLEAR_TOP} set * by this method, along with any others required for proper up navigation as outlined * in the Android Design Guide. * * <p>This method should be used when performing up navigation from within the same task * as the destination. If up navigation should cross tasks in some cases, see * {@link #supportShouldUpRecreateTask(Intent)}.</p> * * @param upIntent An intent representing the target destination for up navigation */ public void supportNavigateUpTo(Intent upIntent) { NavUtils.navigateUpTo(this, upIntent); } @Override public final ActionBarDrawerToggle.Delegate getDrawerToggleDelegate() { return mImpl.getDrawerToggleDelegate(); } public boolean isSupportImplReady() { return mImpl != null; } }