android.support.v4.app
Class ActivityCompat

java.lang.Object
  android.support.v4.app.ActivityCompat

public class ActivityCompat
extends Object

Helper for accessing features in Activity introduced after API level 4 in a backwards compatible fashion.

Constructor Summary

ActivityCompat()

Method Summary

static boolean	invalidateOptionsMenu(android.app.Activity activity) Invalidate the activity's options menu, if able.
static boolean	startActivities(android.app.Activity activity, android.content.Intent[] intents) Start a set of activities as a synthesized task stack, if able.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ActivityCompat

public ActivityCompat()

Method Detail

invalidateOptionsMenu

public static boolean invalidateOptionsMenu(android.app.Activity activity)

Invalidate the activity's options menu, if able.

Before API level 11 (Android 3.0/Honeycomb) the lifecycle of the options menu was controlled primarily by the user's operation of the hardware menu key. When the user presses down on the menu key for the first time the menu was created and prepared by calls to Activity.onCreateOptionsMenu(android.view.Menu) and Activity.onPrepareOptionsMenu(android.view.Menu) respectively. Subsequent presses of the menu key kept the existing instance of the Menu itself and called Activity.onPrepareOptionsMenu(android.view.Menu) to give the activity an opportunity to contextually alter the menu before the menu panel was shown.

In Android 3.0+ the Action Bar forces the options menu to be built early so that items chosen to show as actions may be displayed when the activity first becomes visible. The Activity method invalidateOptionsMenu forces the entire menu to be destroyed and recreated from Activity.onCreateOptionsMenu(android.view.Menu), offering a similar though heavier-weight opportunity to change the menu's contents. Normally this functionality is used to support a changing configuration of Fragments.

Applications may use this support helper to signal a significant change in activity state that should cause the options menu to be rebuilt. If the app is running on an older platform version that does not support menu invalidation the app will still receive Activity.onPrepareOptionsMenu(android.view.Menu) the next time the user presses the menu key and this method will return false. If this method returns true the options menu was successfully invalidated.

Parameters:

activity - Invalidate the options menu of this activity

Returns:

true if this operation was supported and it completed; false if it was not available.

startActivities

public static boolean startActivities(android.app.Activity activity,
                                      android.content.Intent[] intents)

Start a set of activities as a synthesized task stack, if able.

In API level 11 (Android 3.0/Honeycomb) the recommended conventions for app navigation using the back key changed. The back key's behavior is local to the current task and does not capture navigation across different tasks. Navigating across tasks and easily reaching the previous task is accomplished through the "recents" UI, accessible through the software-provided Recents key on the navigation or system bar. On devices with the older hardware button configuration the recents UI can be accessed with a long press on the Home key.

When crossing from one task stack to another post-Android 3.0, the application should synthesize a back stack/history for the new task so that the user may navigate out of the new task and back to the Launcher by repeated presses of the back key. Back key presses should not navigate across task stacks.

startActivities provides a mechanism for constructing a synthetic task stack of multiple activities. If the underlying API is not available on the system this method will return false.

Parameters:

activity - Start activities using this activity as the starting context

intents - Array of intents defining the activities that will be started. The element length-1 will correspond to the top activity on the resulting task stack.

Returns:

true if the underlying API was available and the call was successful, false otherwise