public abstract class ActionProvider extends Object
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:
MenuItem
directly by calling
MenuItem.setActionProvider(ActionProvider)
.
<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" />
Modifier and Type | Class and Description |
---|---|
static interface |
ActionProvider.SubUiVisibilityListener |
static interface |
ActionProvider.VisibilityListener
Listens to changes in visibility as reported by
refreshVisibility() . |
Constructor and Description |
---|
ActionProvider(Context context)
Creates a new instance.
|
Modifier and Type | Method and Description |
---|---|
boolean |
hasSubMenu()
Determines if this ActionProvider has a submenu associated with it.
|
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. |
abstract View |
onCreateActionView()
Deprecated.
|
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
isVisible() will be used
by the MenuItem this ActionProvider is bound to help determine its visibility. |
void |
refreshVisibility()
If this ActionProvider is associated with an item in a menu,
refresh the visibility of the item based on
overridesItemVisibility() and
isVisible() . |
void |
reset() |
void |
setSubUiVisibilityListener(ActionProvider.SubUiVisibilityListener listener) |
void |
setVisibilityListener(ActionProvider.VisibilityListener listener)
Set a listener to be notified when this ActionProvider's overridden visibility changes.
|
void |
subUiVisibilityChanged(boolean isVisible)
Notify the system that the visibility of an action view's sub-UI such as
an anchored popup has changed.
|
public ActionProvider(Context context)
context
- Context for accessing resources.public abstract View onCreateActionView()
onCreateActionView(MenuItem)
This method has been deprecated in favor of onCreateActionView(MenuItem)
.
Newer apps that wish to support platform versions prior to API 16 should also
implement this method to return a valid action view.
public View onCreateActionView(MenuItem forItem)
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.
forItem
- MenuItem to create the action view forpublic boolean overridesItemVisibility()
isVisible()
will be used
by the MenuItem
this ActionProvider is bound to help determine its visibility.isVisible()
public boolean isVisible()
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.
public void refreshVisibility()
overridesItemVisibility()
and
isVisible()
. If overridesItemVisibility()
returns false, this call
will have no effect.public boolean onPerformDefaultAction()
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:
MenuItem.OnMenuItemClickListener.onMenuItemClick
.
Activity.onOptionsItemSelected(MenuItem)
Fragment.onOptionsItemSelected(MenuItem)
Intent
set via
MenuItem.setIntent(android.content.Intent)
The default implementation does not perform any action and returns false.
public boolean hasSubMenu()
Associated submenus will be shown when an action view is not. This
provider instance will receive a call to onPrepareSubMenu(SubMenu)
after the call to onPerformDefaultAction()
and before a submenu is
displayed to the user.
public void onPrepareSubMenu(SubMenu subMenu)
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.
subMenu
- Submenu that will be displayedpublic void subUiVisibilityChanged(boolean isVisible)
public void setSubUiVisibilityListener(ActionProvider.SubUiVisibilityListener listener)
public void setVisibilityListener(ActionProvider.VisibilityListener listener)
listener
- listener to setpublic void reset()