ActionProvider
public
abstract
class
ActionProvider
extends Object
java.lang.Object | |
↳ | android.view.ActionProvider |
An ActionProvider defines rich menu interaction in a single component. ActionProvider can generate action views for use in the action bar, dynamically populate submenus of a MenuItem, and handle default menu item invocations.
An ActionProvider can be optionally specified for a MenuItem
and will be
responsible for creating the action view that appears in the ActionBar
in place of a simple button in the bar. When the menu item is presented in a way that
does not allow custom action views, (e.g. in an overflow menu,) the ActionProvider
can perform a default action.
There are two ways to use an action provider:
-
Set the action provider on a
MenuItem
directly by callingMenuItem#setActionProvider(ActionProvider)
. -
Declare the action provider in an XML menu resource. For example:
<item android:id="@+id/my_menu_item" android:title="Title" android:icon="@drawable/my_menu_item_icon" android:showAsAction="ifRoom" android:actionProviderClass="foo.bar.SomeActionProvider" />
Summary
Nested classes | |
---|---|
interface |
ActionProvider.VisibilityListener
Listens to changes in visibility as reported by |
Public constructors | |
---|---|
ActionProvider(Context context)
Creates a new instance. |
Public methods | |
---|---|
boolean
|
hasSubMenu()
Determines if this ActionProvider has a submenu associated with it. |
boolean
|
isVisible()
If |
abstract
View
|
onCreateActionView()
This method was deprecated
in API level 16.
use |
View
|
onCreateActionView(MenuItem forItem)
Factory method called by the Android framework to create new action views. |
boolean
|
onPerformDefaultAction()
Performs an optional default action. |
void
|
onPrepareSubMenu(SubMenu subMenu)
Called to prepare an associated submenu for the menu item backed by this ActionProvider. |
boolean
|
overridesItemVisibility()
The result of this method determines whether or not |
void
|
refreshVisibility()
If this ActionProvider is associated with an item in a menu,
refresh the visibility of the item based on |
void
|
setVisibilityListener(ActionProvider.VisibilityListener listener)
Set a listener to be notified when this ActionProvider's overridden visibility changes. |
Inherited methods | |
---|---|
Public constructors
ActionProvider
public ActionProvider (Context context)
Creates a new instance. ActionProvider classes should always implement a constructor that takes a single Context parameter for inflating from menu XML.
Parameters | |
---|---|
context |
Context : Context for accessing resources.
This value cannot be null . |
Public methods
hasSubMenu
public boolean hasSubMenu ()
Determines if this ActionProvider has a submenu associated with it.
Associated submenus will be shown when an action view is not. This
provider instance will receive a call to onPrepareSubMenu(android.view.SubMenu)
after the call to onPerformDefaultAction()
and before a submenu is
displayed to the user.
Returns | |
---|---|
boolean |
true if the item backed by this provider should have an associated submenu |
isVisible
public boolean isVisible ()
If overridesItemVisibility()
returns true, the return value of this method
will help determine the visibility of the MenuItem
this ActionProvider is bound to.
If the MenuItem's visibility is explicitly set to false by the application, the MenuItem will not be shown, even if this method returns true.
Returns | |
---|---|
boolean |
true if the MenuItem this ActionProvider is bound to is visible, false if it is invisible. The default implementation returns true. |
onCreateActionView
public abstract View onCreateActionView ()
This method was deprecated
in API level 16.
use onCreateActionView(android.view.MenuItem)
Factory method called by the Android framework to create new action views.
This method has been deprecated in favor of onCreateActionView(android.view.MenuItem)
.
Newer apps that wish to support platform versions prior to API 16 should also
implement this method to return a valid action view.
Returns | |
---|---|
View |
A new action view.
This value cannot be null . |
onCreateActionView
public View onCreateActionView (MenuItem forItem)
Factory method called by the Android framework to create new action views. This method returns a new action view for the given MenuItem.
If your ActionProvider implementation overrides the deprecated no-argument overload
onCreateActionView()
, overriding this method for devices running API 16 or later
is recommended but optional. The default implementation calls onCreateActionView()
for compatibility with applications written for older platform versions.
Parameters | |
---|---|
forItem |
MenuItem : MenuItem to create the action view for
This value cannot be null . |
Returns | |
---|---|
View |
the new action view
This value cannot be null . |
onPerformDefaultAction
public boolean onPerformDefaultAction ()
Performs an optional default action.
For the case of an action provider placed in a menu item not shown as an action this method is invoked if previous callbacks for processing menu selection has handled the event.
A menu item selection is processed in the following order:
-
Receiving a call to
MenuItem.OnMenuItemClickListener.onMenuItemClick
. -
Receiving a call to
Activity.onOptionsItemSelected(MenuItem)
-
Receiving a call to
Fragment.onOptionsItemSelected(MenuItem)
-
Launching the
Intent
set viaMenuItem.setIntent(android.content.Intent)
- Invoking this method.
The default implementation does not perform any action and returns false.
Returns | |
---|---|
boolean |
onPrepareSubMenu
public void onPrepareSubMenu (SubMenu subMenu)
Called to prepare an associated submenu for the menu item backed by this ActionProvider.
if hasSubMenu()
returns true, this method will be called when the
menu item is selected to prepare the submenu for presentation to the user. Apps
may use this to create or alter submenu content right before display.
Parameters | |
---|---|
subMenu |
SubMenu : Submenu that will be displayed
This value cannot be null . |
overridesItemVisibility
public boolean overridesItemVisibility ()
The result of this method determines whether or not isVisible()
will be used
by the MenuItem
this ActionProvider is bound to help determine its visibility.
Returns | |
---|---|
boolean |
true if this ActionProvider overrides the visibility of the MenuItem it is bound to, false otherwise. The default implementation returns false. |
See also:
refreshVisibility
public void refreshVisibility ()
If this ActionProvider is associated with an item in a menu,
refresh the visibility of the item based on overridesItemVisibility()
and
isVisible()
. If overridesItemVisibility()
returns false, this call
will have no effect.
setVisibilityListener
public void setVisibilityListener (ActionProvider.VisibilityListener listener)
Set a listener to be notified when this ActionProvider's overridden visibility changes. This should only be used by MenuItem implementations.
Parameters | |
---|---|
listener |
ActionProvider.VisibilityListener : listener to set
This value may be null . |
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Last updated 2024-04-11 UTC.