Activity

Class Overview

An activity is a single, focused thing that the user can do. Almost all activities interact with the user, so the Activity class takes care of creating a window for you in which you can place your UI with setContentView(View). While activities are often presented to the user as full-screen windows, they can also be used in other ways: as floating windows (via a theme with windowIsFloating set) or embedded inside of another activity (using ActivityGroup). There are two methods almost all subclasses of Activity will implement:

• onCreate(Bundle) is where you initialize your activity. Most importantly, here you will usually call setContentView(int) with a layout resource defining your UI, and using findViewById(int) to retrieve the widgets in that UI that you need to interact with programmatically.
• onPause() is where you deal with the user leaving your activity. Most importantly, any changes made by the user should at this point be committed (usually to the ContentProvider holding the data).

To be of use with Context.startActivity(), all activity classes must have a corresponding <activity> declaration in their package's AndroidManifest.xml.

Topics covered here:

1. Fragments
2. Activity Lifecycle
3. Configuration Changes
4. Starting Activities and Getting Results
5. Saving Persistent State
6. Permissions
7. Process Lifecycle

Fragments

Starting with HONEYCOMB, Activity implementations can make use of the Fragment class to better modularize their code, build more sophisticated user interfaces for larger screens, and help scale their application between small and large screens.

Activity Lifecycle

Activities in the system are managed as an activity stack. When a new activity is started, it is placed on the top of the stack and becomes the running activity -- the previous activity always remains below it in the stack, and will not come to the foreground again until the new activity exits.

An activity has essentially four states:

• If an activity in the foreground of the screen (at the top of the stack), it is active or running.
• If an activity has lost focus but is still visible (that is, a new non-full-sized or transparent activity has focus on top of your activity), it is paused. A paused activity is completely alive (it maintains all state and member information and remains attached to the window manager), but can be killed by the system in extreme low memory situations.
• If an activity is completely obscured by another activity, it is stopped. It still retains all state and member information, however, it is no longer visible to the user so its window is hidden and it will often be killed by the system when memory is needed elsewhere.
• If an activity is paused or stopped, the system can drop the activity from memory by either asking it to finish, or simply killing its process. When it is displayed again to the user, it must be completely restarted and restored to its previous state.

The following diagram shows the important state paths of an Activity. The square rectangles represent callback methods you can implement to perform operations when the Activity moves between states. The colored ovals are major states the Activity can be in.

There are three key loops you may be interested in monitoring within your activity:

• The entire lifetime of an activity happens between the first call to onCreate(Bundle) through to a single final call to onDestroy(). An activity will do all setup of "global" state in onCreate(), and release all remaining resources in onDestroy(). For example, if it has a thread running in the background to download data from the network, it may create that thread in onCreate() and then stop the thread in onDestroy().
• The visible lifetime of an activity happens between a call to onStart() until a corresponding call to onStop(). During this time the user can see the activity on-screen, though it may not be in the foreground and interacting with the user. Between these two methods you can maintain resources that are needed to show the activity to the user. For example, you can register a BroadcastReceiver in onStart() to monitor for changes that impact your UI, and unregister it in onStop() when the user no longer sees what you are displaying. The onStart() and onStop() methods can be called multiple times, as the activity becomes visible and hidden to the user.
• The foreground lifetime of an activity happens between a call to onResume() until a corresponding call to onPause(). During this time the activity is in front of all other activities and interacting with the user. An activity can frequently go between the resumed and paused states -- for example when the device goes to sleep, when an activity result is delivered, when a new intent is delivered -- so the code in these methods should be fairly lightweight.

The entire lifecycle of an activity is defined by the following Activity methods. All of these are hooks that you can override to do appropriate work when the activity changes state. All activities will implement onCreate(Bundle) to do their initial setup; many will also implement onPause() to commit changes to data and otherwise prepare to stop interacting with the user. You should always call up to your superclass when implementing these methods.

 public class Activity extends ApplicationContext {
     protected void onCreate(Bundle savedInstanceState);

     protected void onStart();
     
     protected void onRestart();

     protected void onResume();

     protected void onPause();

     protected void onStop();

     protected void onDestroy();
 }
 

In general the movement through an activity's lifecycle looks like this:

Note the "Killable" column in the above table -- for those methods that are marked as being killable, after that method returns the process hosting the activity may killed by the system at any time without another line of its code being executed. Because of this, you should use the onPause() method to write any persistent data (such as user edits) to storage. In addition, the method onSaveInstanceState(Bundle) is called before placing the activity in such a background state, allowing you to save away any dynamic instance state in your activity into the given Bundle, to be later received in onCreate(Bundle) if the activity needs to be re-created. See the Process Lifecycle section for more information on how the lifecycle of a process is tied to the activities it is hosting. Note that it is important to save persistent data in onPause() instead of onSaveInstanceState(Bundle) because the latter is not part of the lifecycle callbacks, so will not be called in every situation as described in its documentation.

Be aware that these semantics will change slightly between applications targeting platforms starting with HONEYCOMB vs. those targeting prior platforms. Starting with Honeycomb, an application is not in the killable state until its onStop() has returned. This impacts when onSaveInstanceState(Bundle) may be called (it may be safely called after onPause() and allows and application to safely wait until onStop() to save persistent state.

For those methods that are not marked as being killable, the activity's process will not be killed by the system starting from the time the method is called and continuing after it returns. Thus an activity is in the killable state, for example, between after onPause() to the start of onResume().

Configuration Changes

If the configuration of the device (as defined by the Resources.Configuration class) changes, then anything displaying a user interface will need to update to match that configuration. Because Activity is the primary mechanism for interacting with the user, it includes special support for handling configuration changes.

Unless you specify otherwise, a configuration change (such as a change in screen orientation, language, input devices, etc) will cause your current activity to be destroyed, going through the normal activity lifecycle process of onPause(), onStop(), and onDestroy() as appropriate. If the activity had been in the foreground or visible to the user, once onDestroy() is called in that instance then a new instance of the activity will be created, with whatever savedInstanceState the previous instance had generated from onSaveInstanceState(Bundle).

This is done because any application resource, including layout files, can change based on any configuration value. Thus the only safe way to handle a configuration change is to re-retrieve all resources, including layouts, drawables, and strings. Because activities must already know how to save their state and re-create themselves from that state, this is a convenient way to have an activity restart itself with a new configuration.

In some special cases, you may want to bypass restarting of your activity based on one or more types of configuration changes. This is done with the android:configChanges attribute in its manifest. For any types of configuration changes you say that you handle there, you will receive a call to your current activity's onConfigurationChanged(Configuration) method instead of being restarted. If a configuration change involves any that you do not handle, however, the activity will still be restarted and onConfigurationChanged(Configuration) will not be called.

Starting Activities and Getting Results

The startActivity(Intent) method is used to start a new activity, which will be placed at the top of the activity stack. It takes a single argument, an Intent, which describes the activity to be executed.

Sometimes you want to get a result back from an activity when it ends. For example, you may start an activity that lets the user pick a person in a list of contacts; when it ends, it returns the person that was selected. To do this, you call the startActivityForResult(Intent, int) version with a second integer parameter identifying the call. The result will come back through your onActivityResult(int, int, Intent) method.

When an activity exits, it can call setResult(int) to return data back to its parent. It must always supply a result code, which can be the standard results RESULT_CANCELED, RESULT_OK, or any custom values starting at RESULT_FIRST_USER. In addition, it can optionally return back an Intent containing any additional data it wants. All of this information appears back on the parent's Activity.onActivityResult(), along with the integer identifier it originally supplied.

If a child activity fails for any reason (such as crashing), the parent activity will receive a result with the code RESULT_CANCELED.

 public class MyActivity extends Activity {
     ...

     static final int PICK_CONTACT_REQUEST = 0;

     protected boolean onKeyDown(int keyCode, KeyEvent event) {
         if (keyCode == KeyEvent.KEYCODE_DPAD_CENTER) {
             // When the user center presses, let them pick a contact.
             startActivityForResult(
                 new Intent(Intent.ACTION_PICK,
                 new Uri("content://contacts")),
                 PICK_CONTACT_REQUEST);
            return true;
         }
         return false;
     }

     protected void onActivityResult(int requestCode, int resultCode,
             Intent data) {
         if (requestCode == PICK_CONTACT_REQUEST) {
             if (resultCode == RESULT_OK) {
                 // A contact was picked.  Here we will just display it
                 // to the user.
                 startActivity(new Intent(Intent.ACTION_VIEW, data));
             }
         }
     }
 }
 

Saving Persistent State

There are generally two kinds of persistent state than an activity will deal with: shared document-like data (typically stored in a SQLite database using a content provider) and internal state such as user preferences.

For content provider data, we suggest that activities use a "edit in place" user model. That is, any edits a user makes are effectively made immediately without requiring an additional confirmation step. Supporting this model is generally a simple matter of following two rules:

• When creating a new document, the backing database entry or file for it is created immediately. For example, if the user chooses to write a new e-mail, a new entry for that e-mail is created as soon as they start entering data, so that if they go to any other activity after that point this e-mail will now appear in the list of drafts.

• When an activity's onPause() method is called, it should commit to the backing content provider or file any changes the user has made. This ensures that those changes will be seen by any other activity that is about to run. You will probably want to commit your data even more aggressively at key times during your activity's lifecycle: for example before starting a new activity, before finishing your own activity, when the user switches between input fields, etc.

This model is designed to prevent data loss when a user is navigating between activities, and allows the system to safely kill an activity (because system resources are needed somewhere else) at any time after it has been paused. Note this implies that the user pressing BACK from your activity does not mean "cancel" -- it means to leave the activity with its current contents saved away. Canceling edits in an activity must be provided through some other mechanism, such as an explicit "revert" or "undo" option.

See the content package for more information about content providers. These are a key aspect of how different activities invoke and propagate data between themselves.

The Activity class also provides an API for managing internal persistent state associated with an activity. This can be used, for example, to remember the user's preferred initial display in a calendar (day view or week view) or the user's default home page in a web browser.

Activity persistent state is managed with the method getPreferences(int), allowing you to retrieve and modify a set of name/value pairs associated with the activity. To use preferences that are shared across multiple application components (activities, receivers, services, providers), you can use the underlying Context.getSharedPreferences() method to retrieve a preferences object stored under a specific name. (Note that it is not possible to share settings data across application packages -- for that you will need a content provider.)

Here is an excerpt from a calendar activity that stores the user's preferred view mode in its persistent settings:

 public class CalendarActivity extends Activity {
     ...

     static final int DAY_VIEW_MODE = 0;
     static final int WEEK_VIEW_MODE = 1;

     private SharedPreferences mPrefs;
     private int mCurViewMode;

     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         SharedPreferences mPrefs = getSharedPreferences();
         mCurViewMode = mPrefs.getInt("view_mode", DAY_VIEW_MODE);
     }

     protected void onPause() {
         super.onPause();
 
         SharedPreferences.Editor ed = mPrefs.edit();
         ed.putInt("view_mode", mCurViewMode);
         ed.commit();
     }
 }
 

Permissions

The ability to start a particular Activity can be enforced when it is declared in its manifest's <activity> tag. By doing so, other applications will need to declare a corresponding <uses-permission> element in their own manifest to be able to start that activity.

When starting an Activity you can set Intent.FLAG_GRANT_READ_URI_PERMISSION and/or Intent.FLAG_GRANT_WRITE_URI_PERMISSION on the Intent. This will grant the Activity access to the specific URIs in the Intent. Access will remain until the Activity has finished (it will remain across the hosting process being killed and other temporary destruction). As of GINGERBREAD, if the Activity was already created and a new Intent is being delivered to onNewIntent(Intent), any newly granted URI permissions will be added to the existing ones it holds.

See the Security and Permissions document for more information on permissions and security in general.

Process Lifecycle

The Android system attempts to keep application process around for as long as possible, but eventually will need to remove old processes when memory runs low. As described in Activity Lifecycle, the decision about which process to remove is intimately tied to the state of the user's interaction with it. In general, there are four states a process can be in based on the activities running in it, listed here in order of importance. The system will kill less important processes (the last ones) before it resorts to killing more important processes (the first ones).

1. The foreground activity (the activity at the top of the screen that the user is currently interacting with) is considered the most important. Its process will only be killed as a last resort, if it uses more memory than is available on the device. Generally at this point the device has reached a memory paging state, so this is required in order to keep the user interface responsive.

2. A visible activity (an activity that is visible to the user but not in the foreground, such as one sitting behind a foreground dialog) is considered extremely important and will not be killed unless that is required to keep the foreground activity running.

3. A background activity (an activity that is not visible to the user and has been paused) is no longer critical, so the system may safely kill its process to reclaim memory for other foreground or visible processes. If its process needs to be killed, when the user navigates back to the activity (making it visible on the screen again), its onCreate(Bundle) method will be called with the savedInstanceState it had previously supplied in onSaveInstanceState(Bundle) so that it can restart itself in the same state as the user last left it.

4. An empty process is one hosting no activities or other application components (such as Service or BroadcastReceiver classes). These are killed very quickly by the system as memory becomes low. For this reason, any background operation you do outside of an activity must be executed in the context of an activity BroadcastReceiver or Service to ensure that the system knows it needs to keep your process around.

Sometimes an Activity may need to do a long-running operation that exists independently of the activity lifecycle itself. An example may be a camera application that allows you to upload a picture to a web site. The upload may take a long time, and the application should allow the user to leave the application will it is executing. To accomplish this, your Activity should start a Service in which the upload takes place. This allows the system to properly prioritize your process (considering it to be more important than other non-visible applications) for the duration of the upload, independent of whether the original activity is paused, stopped, or finished.

Summary

[Expand] Inherited Constants
From class android.content.Context String ACCESSIBILITY_SERVICE Use with getSystemService(String) to retrieve a AccessibilityManager for giving the user feedback for UI events through the registered event listeners. String ACCOUNT_SERVICE Use with getSystemService(String) to retrieve a AccountManager for receiving intents at a time of your choosing. String ACTIVITY_SERVICE Use with getSystemService(String) to retrieve a ActivityManager for interacting with the global system state. String ALARM_SERVICE Use with getSystemService(String) to retrieve a AlarmManager for receiving intents at a time of your choosing. String APP_OPS_SERVICE Use with getSystemService(String) to retrieve a AppOpsManager for tracking application operations on the device. String AUDIO_SERVICE Use with getSystemService(String) to retrieve a AudioManager for handling management of volume, ringer modes and audio routing. int BIND_ABOVE_CLIENT Flag for bindService(Intent, ServiceConnection, int): indicates that the client application binding to this service considers the service to be more important than the app itself. int BIND_ADJUST_WITH_ACTIVITY Flag for bindService(Intent, ServiceConnection, int): If binding from an activity, allow the target service's process importance to be raised based on whether the activity is visible to the user, regardless whether another flag is used to reduce the amount that the client process's overall importance is used to impact it. int BIND_ALLOW_OOM_MANAGEMENT Flag for bindService(Intent, ServiceConnection, int): allow the process hosting the bound service to go through its normal memory management. int BIND_AUTO_CREATE Flag for bindService(Intent, ServiceConnection, int): automatically create the service as long as the binding exists. int BIND_DEBUG_UNBIND Flag for bindService(Intent, ServiceConnection, int): include debugging help for mismatched calls to unbind. int BIND_IMPORTANT Flag for bindService(Intent, ServiceConnection, int): this service is very important to the client, so should be brought to the foreground process level when the client is. int BIND_NOT_FOREGROUND Flag for bindService(Intent, ServiceConnection, int): don't allow this binding to raise the target service's process to the foreground scheduling priority. int BIND_WAIVE_PRIORITY Flag for bindService(Intent, ServiceConnection, int): don't impact the scheduling or memory management priority of the target service's hosting process. String BLUETOOTH_SERVICE Use with getSystemService(String) to retrieve a BluetoothAdapter for using Bluetooth. String CAPTIONING_SERVICE Use with getSystemService(String) to retrieve a CaptioningManager for obtaining captioning properties and listening for changes in captioning preferences. String CLIPBOARD_SERVICE Use with getSystemService(String) to retrieve a ClipboardManager for accessing and modifying the contents of the global clipboard. String CONNECTIVITY_SERVICE Use with getSystemService(String) to retrieve a ConnectivityManager for handling management of network connections. String CONSUMER_IR_SERVICE Use with getSystemService(String) to retrieve a ConsumerIrManager for transmitting infrared signals from the device. int CONTEXT_IGNORE_SECURITY Flag for use with createPackageContext(String, int): ignore any security restrictions on the Context being requested, allowing it to always be loaded. int CONTEXT_INCLUDE_CODE Flag for use with createPackageContext(String, int): include the application code with the context. int CONTEXT_RESTRICTED Flag for use with createPackageContext(String, int): a restricted context may disable specific features. String DEVICE_POLICY_SERVICE Use with getSystemService(String) to retrieve a DevicePolicyManager for working with global device policy management. String DISPLAY_SERVICE Use with getSystemService(String) to retrieve a DisplayManager for interacting with display devices. String DOWNLOAD_SERVICE Use with getSystemService(String) to retrieve a DownloadManager for requesting HTTP downloads. String DROPBOX_SERVICE Use with getSystemService(String) to retrieve a DropBoxManager instance for recording diagnostic logs. String INPUT_METHOD_SERVICE Use with getSystemService(String) to retrieve a InputMethodManager for accessing input methods. String INPUT_SERVICE Use with getSystemService(String) to retrieve a InputManager for interacting with input devices. String KEYGUARD_SERVICE Use with getSystemService(String) to retrieve a NotificationManager for controlling keyguard. String LAYOUT_INFLATER_SERVICE Use with getSystemService(String) to retrieve a LayoutInflater for inflating layout resources in this context. String LOCATION_SERVICE Use with getSystemService(String) to retrieve a LocationManager for controlling location updates. String MEDIA_ROUTER_SERVICE Use with getSystemService(String) to retrieve a MediaRouter for controlling and managing routing of media. int MODE_APPEND File creation mode: for use with openFileOutput(String, int), if the file already exists then write data to the end of the existing file instead of erasing it. int MODE_ENABLE_WRITE_AHEAD_LOGGING Database open flag: when set, the database is opened with write-ahead logging enabled by default. int MODE_MULTI_PROCESS SharedPreference loading flag: when set, the file on disk will be checked for modification even if the shared preferences instance is already loaded in this process. int MODE_PRIVATE File creation mode: the default mode, where the created file can only be accessed by the calling application (or all applications sharing the same user ID). int MODE_WORLD_READABLE This constant was deprecated in API level 17. Creating world-readable files is very dangerous, and likely to cause security holes in applications. It is strongly discouraged; instead, applications should use more formal mechanism for interactions such as ContentProvider, BroadcastReceiver, and Service. There are no guarantees that this access mode will remain on a file, such as when it goes through a backup and restore. File creation mode: allow all other applications to have read access to the created file. int MODE_WORLD_WRITEABLE This constant was deprecated in API level 17. Creating world-writable files is very dangerous, and likely to cause security holes in applications. It is strongly discouraged; instead, applications should use more formal mechanism for interactions such as ContentProvider, BroadcastReceiver, and Service. There are no guarantees that this access mode will remain on a file, such as when it goes through a backup and restore. File creation mode: allow all other applications to have write access to the created file. String NFC_SERVICE Use with getSystemService(String) to retrieve a NfcManager for using NFC. String NOTIFICATION_SERVICE Use with getSystemService(String) to retrieve a NotificationManager for informing the user of background events. String NSD_SERVICE Use with getSystemService(String) to retrieve a NsdManager for handling management of network service discovery String POWER_SERVICE Use with getSystemService(String) to retrieve a PowerManager for controlling power management, including "wake locks," which let you keep the device on while you're running long tasks. String PRINT_SERVICE PrintManager for printing and managing printers and print tasks. String SEARCH_SERVICE Use with getSystemService(String) to retrieve a SearchManager for handling searches. String SENSOR_SERVICE Use with getSystemService(String) to retrieve a SensorManager for accessing sensors. String STORAGE_SERVICE Use with getSystemService(String) to retrieve a StorageManager for accessing system storage functions. String TELEPHONY_SERVICE Use with getSystemService(String) to retrieve a TelephonyManager for handling management the telephony features of the device. String TEXT_SERVICES_MANAGER_SERVICE Use with getSystemService(String) to retrieve a TextServicesManager for accessing text services. String UI_MODE_SERVICE Use with getSystemService(String) to retrieve a UiModeManager for controlling UI modes. String USB_SERVICE Use with getSystemService(String) to retrieve a UsbManager for access to USB devices (as a USB host) and for controlling this device's behavior as a USB device. String USER_SERVICE Use with getSystemService(String) to retrieve a UserManager for managing users on devices that support multiple users. String VIBRATOR_SERVICE Use with getSystemService(String) to retrieve a Vibrator for interacting with the vibration hardware. String WALLPAPER_SERVICE Use with getSystemService(String) to retrieve a com.android.server.WallpaperService for accessing wallpapers. String WIFI_P2P_SERVICE Use with getSystemService(String) to retrieve a WifiP2pManager for handling management of Wi-Fi peer-to-peer connections. String WIFI_SERVICE Use with getSystemService(String) to retrieve a WifiManager for handling management of Wi-Fi access. String WINDOW_SERVICE Use with getSystemService(String) to retrieve a WindowManager for accessing the system's window manager.
From interface android.content.ComponentCallbacks2 int TRIM_MEMORY_BACKGROUND Level for onTrimMemory(int): the process has gone on to the LRU list. int TRIM_MEMORY_COMPLETE Level for onTrimMemory(int): the process is nearing the end of the background LRU list, and if more memory isn't found soon it will be killed. int TRIM_MEMORY_MODERATE Level for onTrimMemory(int): the process is around the middle of the background LRU list; freeing memory can help the system keep other processes running later in the list for better overall performance. int TRIM_MEMORY_RUNNING_CRITICAL Level for onTrimMemory(int): the process is not an expendable background process, but the device is running extremely low on memory and is about to not be able to keep any background processes running. int TRIM_MEMORY_RUNNING_LOW Level for onTrimMemory(int): the process is not an expendable background process, but the device is running low on memory. int TRIM_MEMORY_RUNNING_MODERATE Level for onTrimMemory(int): the process is not an expendable background process, but the device is running moderately low on memory. int TRIM_MEMORY_UI_HIDDEN Level for onTrimMemory(int): the process had been showing a user interface, and is no longer doing so.

[Expand] Inherited Methods
From class android.view.ContextThemeWrapper void applyOverrideConfiguration(Configuration overrideConfiguration) Call to set an "override configuration" on this context -- this is a configuration that replies one or more values of the standard configuration that is applied to the context. void attachBaseContext(Context newBase) Set the base context for this ContextWrapper. Resources getResources() Return a Resources instance for your application's package. Object getSystemService(String name) Return the handle to a system-level service by name. Resources.Theme getTheme() Return the Theme object associated with this Context. void onApplyThemeResource(Resources.Theme theme, int resid, boolean first) Called by setTheme(int) and getTheme() to apply a theme resource to the current Theme object. void setTheme(int resid) Set the base theme for this context.
From class android.content.ContextWrapper void attachBaseContext(Context base) Set the base context for this ContextWrapper. boolean bindService(Intent service, ServiceConnection conn, int flags) Connect to an application service, creating it if needed. int checkCallingOrSelfPermission(String permission) Determine whether the calling process of an IPC or you have been granted a particular permission. int checkCallingOrSelfUriPermission(Uri uri, int modeFlags) Determine whether the calling process of an IPC or you has been granted permission to access a specific URI. int checkCallingPermission(String permission) Determine whether the calling process of an IPC you are handling has been granted a particular permission. int checkCallingUriPermission(Uri uri, int modeFlags) Determine whether the calling process and user ID has been granted permission to access a specific URI. int checkPermission(String permission, int pid, int uid) Determine whether the given permission is allowed for a particular process and user ID running in the system. int checkUriPermission(Uri uri, int pid, int uid, int modeFlags) Determine whether a particular process and user ID has been granted permission to access a specific URI. int checkUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags) Check both a Uri and normal permission. void clearWallpaper() This method is deprecated. Use WallpaperManager.clear() instead. This method requires the caller to hold the permission SET_WALLPAPER. Context createConfigurationContext(Configuration overrideConfiguration) Return a new Context object for the current Context but whose resources are adjusted to match the given Configuration. Context createDisplayContext(Display display) Return a new Context object for the current Context but whose resources are adjusted to match the metrics of the given Display. Context createPackageContext(String packageName, int flags) Return a new Context object for the given application name. String[] databaseList() Returns an array of strings naming the private databases associated with this Context's application package. boolean deleteDatabase(String name) Delete an existing private SQLiteDatabase associated with this Context's application package. boolean deleteFile(String name) Delete the given private file associated with this Context's application package. void enforceCallingOrSelfPermission(String permission, String message) If neither you nor the calling process of an IPC you are handling has been granted a particular permission, throw a SecurityException. void enforceCallingOrSelfUriPermission(Uri uri, int modeFlags, String message) If the calling process of an IPC or you has not been granted permission to access a specific URI, throw SecurityException. void enforceCallingPermission(String permission, String message) If the calling process of an IPC you are handling has not been granted a particular permission, throw a SecurityException. void enforceCallingUriPermission(Uri uri, int modeFlags, String message) If the calling process and user ID has not been granted permission to access a specific URI, throw SecurityException. void enforcePermission(String permission, int pid, int uid, String message) If the given permission is not allowed for a particular process and user ID running in the system, throw a SecurityException. void enforceUriPermission(Uri uri, int pid, int uid, int modeFlags, String message) If a particular process and user ID has not been granted permission to access a specific URI, throw SecurityException. void enforceUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags, String message) Enforce both a Uri and normal permission. String[] fileList() Returns an array of strings naming the private files associated with this Context's application package. Context getApplicationContext() Return the context of the single, global Application object of the current process. ApplicationInfo getApplicationInfo() Return the full application info for this context's package. AssetManager getAssets() Return an AssetManager instance for your application's package. Context getBaseContext() File getCacheDir() Returns the absolute path to the application specific cache directory on the filesystem. ClassLoader getClassLoader() Return a class loader you can use to retrieve classes in this package. ContentResolver getContentResolver() Return a ContentResolver instance for your application's package. File getDatabasePath(String name) Returns the absolute path on the filesystem where a database created with openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory) is stored. File getDir(String name, int mode) Retrieve, creating if needed, a new directory in which the application can place its own custom data files. File getExternalCacheDir() Returns the absolute path to the directory on the primary external filesystem (that is somewhere on Environment.getExternalStorageDirectory() where the application can place cache files it owns. File[] getExternalCacheDirs() Returns absolute paths to application-specific directories on all external storage devices where the application can place cache files it owns. File getExternalFilesDir(String type) Returns the absolute path to the directory on the primary external filesystem (that is somewhere on Environment.getExternalStorageDirectory()) where the application can place persistent files it owns. File[] getExternalFilesDirs(String type) Returns absolute paths to application-specific directories on all external storage devices where the application can place persistent files it owns. File getFileStreamPath(String name) Returns the absolute path on the filesystem where a file created with openFileOutput(String, int) is stored. File getFilesDir() Returns the absolute path to the directory on the filesystem where files created with openFileOutput(String, int) are stored. Looper getMainLooper() Return the Looper for the main thread of the current process. File getObbDir() Return the primary external storage directory where this application's OBB files (if there are any) can be found. File[] getObbDirs() Returns absolute paths to application-specific directories on all external storage devices where the application's OBB files (if there are any) can be found. String getPackageCodePath() Return the full path to this context's primary Android package. PackageManager getPackageManager() Return PackageManager instance to find global package information. String getPackageName() Return the name of this application's package. String getPackageResourcePath() Return the full path to this context's primary Android package. Resources getResources() Return a Resources instance for your application's package. SharedPreferences getSharedPreferences(String name, int mode) Retrieve and hold the contents of the preferences file 'name', returning a SharedPreferences through which you can retrieve and modify its values. Object getSystemService(String name) Return the handle to a system-level service by name. Resources.Theme getTheme() Return the Theme object associated with this Context. Drawable getWallpaper() This method is deprecated. Use WallpaperManager.get() instead. int getWallpaperDesiredMinimumHeight() This method is deprecated. Use WallpaperManager.getDesiredMinimumHeight() instead. int getWallpaperDesiredMinimumWidth() This method is deprecated. Use WallpaperManager.getDesiredMinimumWidth() instead. void grantUriPermission(String toPackage, Uri uri, int modeFlags) Grant permission to access a specific Uri to another package, regardless of whether that package has general permission to access the Uri's content provider. boolean isRestricted() Indicates whether this Context is restricted. FileInputStream openFileInput(String name) Open a private file associated with this Context's application package for reading. FileOutputStream openFileOutput(String name, int mode) Open a private file associated with this Context's application package for writing. SQLiteDatabase openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory) Open a new private SQLiteDatabase associated with this Context's application package. SQLiteDatabase openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler) Open a new private SQLiteDatabase associated with this Context's application package. Drawable peekWallpaper() This method is deprecated. Use WallpaperManager.peek() instead. Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter) Register a BroadcastReceiver to be run in the main activity thread. Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter, String broadcastPermission, Handler scheduler) Register to receive intent broadcasts, to run in the context of scheduler. void removeStickyBroadcast(Intent intent) Remove the data previously sent with sendStickyBroadcast(Intent), so that it is as if the sticky broadcast had never happened. void removeStickyBroadcastAsUser(Intent intent, UserHandle user) Version of removeStickyBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. void revokeUriPermission(Uri uri, int modeFlags) Remove all permissions to access a particular content provider Uri that were previously added with grantUriPermission(String, Uri, int). void sendBroadcast(Intent intent) Broadcast the given intent to all interested BroadcastReceivers. void sendBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, allowing an optional required permission to be enforced. void sendBroadcastAsUser(Intent intent, UserHandle user) Version of sendBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. void sendBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission) Version of sendBroadcast(Intent, String) that allows you to specify the user the broadcast will be sent to. void sendOrderedBroadcast(Intent intent, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendBroadcast(Intent) that allows you to receive data back from the broadcast. void sendOrderedBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, delivering them one at a time to allow more preferred receivers to consume the broadcast before it is delivered to less preferred receivers. void sendOrderedBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendOrderedBroadcast(Intent, String, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. void sendStickyBroadcast(Intent intent) Perform a sendBroadcast(Intent) that is "sticky," meaning the Intent you are sending stays around after the broadcast is complete, so that others can quickly retrieve that data through the return value of registerReceiver(BroadcastReceiver, IntentFilter). void sendStickyBroadcastAsUser(Intent intent, UserHandle user) Version of sendStickyBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. void sendStickyOrderedBroadcast(Intent intent, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendStickyBroadcast(Intent) that allows you to receive data back from the broadcast. void sendStickyOrderedBroadcastAsUser(Intent intent, UserHandle user, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendStickyOrderedBroadcast(Intent, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. void setTheme(int resid) Set the base theme for this context. void setWallpaper(Bitmap bitmap) This method is deprecated. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER. void setWallpaper(InputStream data) This method is deprecated. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER. void startActivities(Intent[] intents) Same as startActivities(Intent[], Bundle) with no options specified. void startActivities(Intent[] intents, Bundle options) Launch multiple new activities. void startActivity(Intent intent) Same as startActivity(Intent, Bundle) with no options specified. void startActivity(Intent intent, Bundle options) Launch a new activity. boolean startInstrumentation(ComponentName className, String profileFile, Bundle arguments) Start executing an Instrumentation class. void startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags, Bundle options) Like startActivity(Intent, Bundle), but taking a IntentSender to start. void startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags) Same as startIntentSender(IntentSender, Intent, int, int, int, Bundle) with no options specified. ComponentName startService(Intent service) Request that a given application service be started. boolean stopService(Intent name) Request that a given application service be stopped. void unbindService(ServiceConnection conn) Disconnect from an application service. void unregisterReceiver(BroadcastReceiver receiver) Unregister a previously registered BroadcastReceiver.
From class android.content.Context abstract boolean bindService(Intent service, ServiceConnection conn, int flags) Connect to an application service, creating it if needed. abstract int checkCallingOrSelfPermission(String permission) Determine whether the calling process of an IPC or you have been granted a particular permission. abstract int checkCallingOrSelfUriPermission(Uri uri, int modeFlags) Determine whether the calling process of an IPC or you has been granted permission to access a specific URI. abstract int checkCallingPermission(String permission) Determine whether the calling process of an IPC you are handling has been granted a particular permission. abstract int checkCallingUriPermission(Uri uri, int modeFlags) Determine whether the calling process and user ID has been granted permission to access a specific URI. abstract int checkPermission(String permission, int pid, int uid) Determine whether the given permission is allowed for a particular process and user ID running in the system. abstract int checkUriPermission(Uri uri, int pid, int uid, int modeFlags) Determine whether a particular process and user ID has been granted permission to access a specific URI. abstract int checkUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags) Check both a Uri and normal permission. abstract void clearWallpaper() This method was deprecated in API level 5. Use WallpaperManager.clear() instead. This method requires the caller to hold the permission SET_WALLPAPER. abstract Context createConfigurationContext(Configuration overrideConfiguration) Return a new Context object for the current Context but whose resources are adjusted to match the given Configuration. abstract Context createDisplayContext(Display display) Return a new Context object for the current Context but whose resources are adjusted to match the metrics of the given Display. abstract Context createPackageContext(String packageName, int flags) Return a new Context object for the given application name. abstract String[] databaseList() Returns an array of strings naming the private databases associated with this Context's application package. abstract boolean deleteDatabase(String name) Delete an existing private SQLiteDatabase associated with this Context's application package. abstract boolean deleteFile(String name) Delete the given private file associated with this Context's application package. abstract void enforceCallingOrSelfPermission(String permission, String message) If neither you nor the calling process of an IPC you are handling has been granted a particular permission, throw a SecurityException. abstract void enforceCallingOrSelfUriPermission(Uri uri, int modeFlags, String message) If the calling process of an IPC or you has not been granted permission to access a specific URI, throw SecurityException. abstract void enforceCallingPermission(String permission, String message) If the calling process of an IPC you are handling has not been granted a particular permission, throw a SecurityException. abstract void enforceCallingUriPermission(Uri uri, int modeFlags, String message) If the calling process and user ID has not been granted permission to access a specific URI, throw SecurityException. abstract void enforcePermission(String permission, int pid, int uid, String message) If the given permission is not allowed for a particular process and user ID running in the system, throw a SecurityException. abstract void enforceUriPermission(Uri uri, int pid, int uid, int modeFlags, String message) If a particular process and user ID has not been granted permission to access a specific URI, throw SecurityException. abstract void enforceUriPermission(Uri uri, String readPermission, String writePermission, int pid, int uid, int modeFlags, String message) Enforce both a Uri and normal permission. abstract String[] fileList() Returns an array of strings naming the private files associated with this Context's application package. abstract Context getApplicationContext() Return the context of the single, global Application object of the current process. abstract ApplicationInfo getApplicationInfo() Return the full application info for this context's package. abstract AssetManager getAssets() Return an AssetManager instance for your application's package. abstract File getCacheDir() Returns the absolute path to the application specific cache directory on the filesystem. abstract ClassLoader getClassLoader() Return a class loader you can use to retrieve classes in this package. abstract ContentResolver getContentResolver() Return a ContentResolver instance for your application's package. abstract File getDatabasePath(String name) Returns the absolute path on the filesystem where a database created with openOrCreateDatabase(String, int, SQLiteDatabase.CursorFactory) is stored. abstract File getDir(String name, int mode) Retrieve, creating if needed, a new directory in which the application can place its own custom data files. abstract File getExternalCacheDir() Returns the absolute path to the directory on the primary external filesystem (that is somewhere on Environment.getExternalStorageDirectory() where the application can place cache files it owns. abstract File[] getExternalCacheDirs() Returns absolute paths to application-specific directories on all external storage devices where the application can place cache files it owns. abstract File getExternalFilesDir(String type) Returns the absolute path to the directory on the primary external filesystem (that is somewhere on Environment.getExternalStorageDirectory()) where the application can place persistent files it owns. abstract File[] getExternalFilesDirs(String type) Returns absolute paths to application-specific directories on all external storage devices where the application can place persistent files it owns. abstract File getFileStreamPath(String name) Returns the absolute path on the filesystem where a file created with openFileOutput(String, int) is stored. abstract File getFilesDir() Returns the absolute path to the directory on the filesystem where files created with openFileOutput(String, int) are stored. abstract Looper getMainLooper() Return the Looper for the main thread of the current process. abstract File getObbDir() Return the primary external storage directory where this application's OBB files (if there are any) can be found. abstract File[] getObbDirs() Returns absolute paths to application-specific directories on all external storage devices where the application's OBB files (if there are any) can be found. abstract String getPackageCodePath() Return the full path to this context's primary Android package. abstract PackageManager getPackageManager() Return PackageManager instance to find global package information. abstract String getPackageName() Return the name of this application's package. abstract String getPackageResourcePath() Return the full path to this context's primary Android package. abstract Resources getResources() Return a Resources instance for your application's package. abstract SharedPreferences getSharedPreferences(String name, int mode) Retrieve and hold the contents of the preferences file 'name', returning a SharedPreferences through which you can retrieve and modify its values. final String getString(int resId) Return a localized string from the application's package's default string table. final String getString(int resId, Object... formatArgs) Return a localized formatted string from the application's package's default string table, substituting the format arguments as defined in Formatter and format(String, Object...). abstract Object getSystemService(String name) Return the handle to a system-level service by name. final CharSequence getText(int resId) Return a localized, styled CharSequence from the application's package's default string table. abstract Resources.Theme getTheme() Return the Theme object associated with this Context. abstract Drawable getWallpaper() This method was deprecated in API level 5. Use WallpaperManager.get() instead. abstract int getWallpaperDesiredMinimumHeight() This method was deprecated in API level 5. Use WallpaperManager.getDesiredMinimumHeight() instead. abstract int getWallpaperDesiredMinimumWidth() This method was deprecated in API level 5. Use WallpaperManager.getDesiredMinimumWidth() instead. abstract void grantUriPermission(String toPackage, Uri uri, int modeFlags) Grant permission to access a specific Uri to another package, regardless of whether that package has general permission to access the Uri's content provider. boolean isRestricted() Indicates whether this Context is restricted. final TypedArray obtainStyledAttributes(int[] attrs) Retrieve styled attribute information in this Context's theme. final TypedArray obtainStyledAttributes(AttributeSet set, int[] attrs, int defStyleAttr, int defStyleRes) Retrieve styled attribute information in this Context's theme. final TypedArray obtainStyledAttributes(AttributeSet set, int[] attrs) Retrieve styled attribute information in this Context's theme. final TypedArray obtainStyledAttributes(int resid, int[] attrs) Retrieve styled attribute information in this Context's theme. abstract FileInputStream openFileInput(String name) Open a private file associated with this Context's application package for reading. abstract FileOutputStream openFileOutput(String name, int mode) Open a private file associated with this Context's application package for writing. abstract SQLiteDatabase openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory) Open a new private SQLiteDatabase associated with this Context's application package. abstract SQLiteDatabase openOrCreateDatabase(String name, int mode, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler) Open a new private SQLiteDatabase associated with this Context's application package. abstract Drawable peekWallpaper() This method was deprecated in API level 5. Use WallpaperManager.peek() instead. void registerComponentCallbacks(ComponentCallbacks callback) Add a new ComponentCallbacks to the base application of the Context, which will be called at the same times as the ComponentCallbacks methods of activities and other components are called. abstract Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter) Register a BroadcastReceiver to be run in the main activity thread. abstract Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter, String broadcastPermission, Handler scheduler) Register to receive intent broadcasts, to run in the context of scheduler. abstract void removeStickyBroadcast(Intent intent) Remove the data previously sent with sendStickyBroadcast(Intent), so that it is as if the sticky broadcast had never happened. abstract void removeStickyBroadcastAsUser(Intent intent, UserHandle user) Version of removeStickyBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. abstract void revokeUriPermission(Uri uri, int modeFlags) Remove all permissions to access a particular content provider Uri that were previously added with grantUriPermission(String, Uri, int). abstract void sendBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, allowing an optional required permission to be enforced. abstract void sendBroadcast(Intent intent) Broadcast the given intent to all interested BroadcastReceivers. abstract void sendBroadcastAsUser(Intent intent, UserHandle user) Version of sendBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. abstract void sendBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission) Version of sendBroadcast(Intent, String) that allows you to specify the user the broadcast will be sent to. abstract void sendOrderedBroadcast(Intent intent, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendBroadcast(Intent) that allows you to receive data back from the broadcast. abstract void sendOrderedBroadcast(Intent intent, String receiverPermission) Broadcast the given intent to all interested BroadcastReceivers, delivering them one at a time to allow more preferred receivers to consume the broadcast before it is delivered to less preferred receivers. abstract void sendOrderedBroadcastAsUser(Intent intent, UserHandle user, String receiverPermission, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendOrderedBroadcast(Intent, String, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. abstract void sendStickyBroadcast(Intent intent) Perform a sendBroadcast(Intent) that is "sticky," meaning the Intent you are sending stays around after the broadcast is complete, so that others can quickly retrieve that data through the return value of registerReceiver(BroadcastReceiver, IntentFilter). abstract void sendStickyBroadcastAsUser(Intent intent, UserHandle user) Version of sendStickyBroadcast(Intent) that allows you to specify the user the broadcast will be sent to. abstract void sendStickyOrderedBroadcast(Intent intent, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendStickyBroadcast(Intent) that allows you to receive data back from the broadcast. abstract void sendStickyOrderedBroadcastAsUser(Intent intent, UserHandle user, BroadcastReceiver resultReceiver, Handler scheduler, int initialCode, String initialData, Bundle initialExtras) Version of sendStickyOrderedBroadcast(Intent, BroadcastReceiver, Handler, int, String, Bundle) that allows you to specify the user the broadcast will be sent to. abstract void setTheme(int resid) Set the base theme for this context. abstract void setWallpaper(InputStream data) This method was deprecated in API level 5. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER. abstract void setWallpaper(Bitmap bitmap) This method was deprecated in API level 5. Use WallpaperManager.set() instead. This method requires the caller to hold the permission SET_WALLPAPER. abstract void startActivities(Intent[] intents, Bundle options) Launch multiple new activities. abstract void startActivities(Intent[] intents) Same as startActivities(Intent[], Bundle) with no options specified. abstract void startActivity(Intent intent) Same as startActivity(Intent, Bundle) with no options specified. abstract void startActivity(Intent intent, Bundle options) Launch a new activity. abstract boolean startInstrumentation(ComponentName className, String profileFile, Bundle arguments) Start executing an Instrumentation class. abstract void startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags, Bundle options) Like startActivity(Intent, Bundle), but taking a IntentSender to start. abstract void startIntentSender(IntentSender intent, Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags) Same as startIntentSender(IntentSender, Intent, int, int, int, Bundle) with no options specified. abstract ComponentName startService(Intent service) Request that a given application service be started. abstract boolean stopService(Intent service) Request that a given application service be stopped. abstract void unbindService(ServiceConnection conn) Disconnect from an application service. void unregisterComponentCallbacks(ComponentCallbacks callback) Remove a ComponentCallbacks object that was previously registered with registerComponentCallbacks(ComponentCallbacks). abstract void unregisterReceiver(BroadcastReceiver receiver) Unregister a previously registered BroadcastReceiver.
From class java.lang.Object Object clone() Creates and returns a copy of this Object. boolean equals(Object o) Compares this instance with the specified object and indicates if they are equal. void finalize() Invoked when the garbage collector has detected that this instance is no longer reachable. final Class<?> getClass() Returns the unique instance of Class that represents this object's class. int hashCode() Returns an integer hash code for this object. final void notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. final void notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up. String toString() Returns a string containing a concise, human-readable description of this object. final void wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object. final void wait(long millis, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires. final void wait(long millis) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
From interface android.content.ComponentCallbacks abstract void onConfigurationChanged(Configuration newConfig) Called by the system when the device configuration changes while your component is running. abstract void onLowMemory() This is called when the overall system is running low on memory, and actively running processes should trim their memory usage.
From interface android.content.ComponentCallbacks2 abstract void onTrimMemory(int level) Called when the operating system has determined that it is a good time for a process to trim unneeded memory from its process.
From interface android.view.KeyEvent.Callback abstract boolean onKeyDown(int keyCode, KeyEvent event) Called when a key down event has occurred. abstract boolean onKeyLongPress(int keyCode, KeyEvent event) Called when a long press has occurred. abstract boolean onKeyMultiple(int keyCode, int count, KeyEvent event) Called when multiple down/up pairs of the same key have occurred in a row. abstract boolean onKeyUp(int keyCode, KeyEvent event) Called when a key up event has occurred.
From interface android.view.LayoutInflater.Factory abstract View onCreateView(String name, Context context, AttributeSet attrs) Hook you can supply that is called when inflating from a LayoutInflater.
From interface android.view.LayoutInflater.Factory2 abstract View onCreateView(View parent, String name, Context context, AttributeSet attrs) Version of onCreateView(String, Context, AttributeSet) that also supplies the parent that the view created view will be placed in.
From interface android.view.View.OnCreateContextMenuListener abstract void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) Called when the context menu for this view is being built.
From interface android.view.Window.Callback abstract boolean dispatchGenericMotionEvent(MotionEvent event) Called to process generic motion events. abstract boolean dispatchKeyEvent(KeyEvent event) Called to process key events. abstract boolean dispatchKeyShortcutEvent(KeyEvent event) Called to process a key shortcut event. abstract boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) Called to process population of AccessibilityEvents. abstract boolean dispatchTouchEvent(MotionEvent event) Called to process touch screen events. abstract boolean dispatchTrackballEvent(MotionEvent event) Called to process trackball events. abstract void onActionModeFinished(ActionMode mode) Called when an action mode has been finished. abstract void onActionModeStarted(ActionMode mode) Called when an action mode has been started. abstract void onAttachedToWindow() Called when the window has been attached to the window manager. abstract void onContentChanged() This hook is called whenever the content view of the screen changes (due to a call to Window.setContentView or Window.addContentView). abstract boolean onCreatePanelMenu(int featureId, Menu menu) Initialize the contents of the menu for panel 'featureId'. abstract View onCreatePanelView(int featureId) Instantiate the view to display in the panel for 'featureId'. abstract void onDetachedFromWindow() Called when the window has been attached to the window manager. abstract boolean onMenuItemSelected(int featureId, MenuItem item) Called when a panel's menu item has been selected by the user. abstract boolean onMenuOpened(int featureId, Menu menu) Called when a panel's menu is opened by the user. abstract void onPanelClosed(int featureId, Menu menu) Called when a panel is being closed. abstract boolean onPreparePanel(int featureId, View view, Menu menu) Prepare a panel to be displayed. abstract boolean onSearchRequested() Called when the user signals the desire to start a search. abstract void onWindowAttributesChanged(WindowManager.LayoutParams attrs) This is called whenever the current window attributes change. abstract void onWindowFocusChanged(boolean hasFocus) This hook is called whenever the window focus changes. abstract ActionMode onWindowStartingActionMode(ActionMode.Callback callback) Called when an action mode is being started for this window.