Android
android.app
public class

android.app.TabActivity

java.lang.Object
android.content.Context
android.content.ContextWrapper
android.view.ContextThemeWrapper
android.app.Activity ComponentCallbacks KeyEvent.Callback LayoutInflater.Factory View.OnCreateContextMenuListener Window.Callback
android.app.ActivityGroup
android.app.TabActivity

An activity that contains and runs multiple embedded activities or views.

Summary

Constants inherited from class android.app.Activity
Constants inherited from class android.content.Context
Fields inherited from class android.app.ActivityGroup

Public Constructors

            TabActivity()

Public Methods

          TabHost  getTabHost()
Returns the TabHost the activity is using to host its tabs.
          TabWidget  getTabWidget()
Returns the TabWidget the activity is using to draw the actual tabs.
          void  onContentChanged()
Updates the screen state (current list and other views) when the content changes.
          void  setDefaultTab(String tag)
Sets the default tab that is the first tab highlighted.
          void  setDefaultTab(int index)
Sets the default tab that is the first tab highlighted.

Protected Methods

          void  onChildTitleChanged(Activity childActivity, CharSequence title)
          void  onPostCreate(Bundle icicle)
Called when activity start-up is complete (after onStart() and onRestoreInstanceState(Bundle) have been called).
          void  onRestoreInstanceState(Bundle state)
This method is called after onStart() when the activity is being re-initialized from a previously saved state, given here in state.
          void  onSaveInstanceState(Bundle outState)
Called to retrieve per-instance state from an activity before being killed so that the state can be restored in onCreate(Bundle) or onRestoreInstanceState(Bundle) (the Bundle populated by this method will be passed to both).
Methods inherited from class android.app.ActivityGroup
Methods inherited from class android.app.Activity
Methods inherited from class android.view.ContextThemeWrapper
Methods inherited from class android.content.ContextWrapper
Methods inherited from class android.content.Context
Methods inherited from class java.lang.Object
Methods inherited from interface android.content.ComponentCallbacks
Methods inherited from interface android.view.KeyEvent.Callback
Methods inherited from interface android.view.LayoutInflater.Factory
Methods inherited from interface android.view.View.OnCreateContextMenuListener
Methods inherited from interface android.view.Window.Callback

Details

Public Constructors

public TabActivity()

Public Methods

public TabHost getTabHost()

Returns the TabHost the activity is using to host its tabs.

Returns

  • the TabHost the activity is using to host its tabs.

public TabWidget getTabWidget()

Returns the TabWidget the activity is using to draw the actual tabs.

Returns

  • the TabWidget the activity is using to draw the actual tabs.

public void onContentChanged()

Updates the screen state (current list and other views) when the content changes.

public void setDefaultTab(String tag)

Sets the default tab that is the first tab highlighted.

Parameters

tag the name of the default tab

public void setDefaultTab(int index)

Sets the default tab that is the first tab highlighted.

Parameters

index the index of the default tab

Protected Methods

protected void onChildTitleChanged(Activity childActivity, CharSequence title)

protected void onPostCreate(Bundle icicle)

Called when activity start-up is complete (after onStart() and onRestoreInstanceState(Bundle) have been called). Applications will generally not implement this method; it is intended for system classes to do final initialization after application code has run.

Derived classes must call through to the super class's implementation of this method. If they do not, an exception will be thrown.

Parameters

icicle If the activity is being re-initialized after previously being shut down then this Bundle contains the data it most recently supplied in onSaveInstanceState(Bundle). Note: Otherwise it is null.

protected void onRestoreInstanceState(Bundle state)

This method is called after onStart() when the activity is being re-initialized from a previously saved state, given here in state. Most implementations will simply use onCreate(Bundle) to restore their state, but it is sometimes convenient to do it here after all of the initialization has been done or to allow subclasses to decide whether to use your default implementation. The default implementation of this method performs a restore of any view state that had previously been frozen by onSaveInstanceState(Bundle).

This method is called between onStart() and onPostCreate(Bundle).

Parameters

state the data most recently supplied in onSaveInstanceState(Bundle).

protected void onSaveInstanceState(Bundle outState)

Called to retrieve per-instance state from an activity before being killed so that the state can be restored in onCreate(Bundle) or onRestoreInstanceState(Bundle) (the Bundle populated by this method will be passed to both).

This method is called before an activity may be killed so that when it comes back some time in the future it can restore its state. For example, if activity B is launched in front of activity A, and at some point activity A is killed to reclaim resources, activity A will have a chance to save the current state of its user interface via this method so that when the user returns to activity A, the state of the user interface can be restored via onCreate(Bundle) or onRestoreInstanceState(Bundle).

Do not confuse this method with activity lifecycle callbacks such as onPause(), which is always called when an activity is being placed in the background or on its way to destruction, or onStop() which is called before destruction. One example of when onPause() and onStop() is called and not this method is when a user navigates back from activity B to activity A: there is no need to call onSaveInstanceState(Bundle) on B because that particular instance will never be restored, so the system avoids calling it. An example when onPause() is called and not onSaveInstanceState(Bundle) is when activity B is launched in front of activity A: the system may avoid calling onSaveInstanceState(Bundle) on activity A if it isn't killed during the lifetime of B since the state of the user interface of A will stay intact.

The default implementation takes care of most of the UI per-instance state for you by calling onSaveInstanceState() on each view in the hierarchy that has an id, and by saving the id of the currently focused view (all of which is restored by the default implementation of onRestoreInstanceState(Bundle)). If you override this method to save additional information not captured by each individual view, you will likely want to call through to the default implementation, otherwise be prepared to save all of the state of each view yourself.

If called, this method will occur before onStop(). There are no guarantees about whether it will occur before or after onPause().

Parameters

outState Bundle in which to place your saved state.
Copyright 2007 Google Inc. Build 0.9_r1-98467 - 14 Aug 2008 18:48