Added in API level 18

ViewGroupOverlay


public class ViewGroupOverlay
extends ViewOverlay

java.lang.Object
   ↳ android.view.ViewOverlay
     ↳ android.view.ViewGroupOverlay


A group overlay is an extra layer that sits on top of a ViewGroup (the "host view") which is drawn after all other content in that view (including the view group's children). Interaction with the overlay layer is done by adding and removing views and drawables.

ViewGroupOverlay is a subclass of ViewOverlay, adding the ability to manage views for overlays on ViewGroups, in addition to the drawable support in ViewOverlay.

Summary

Public methods

void add(View view)

Adds a View to the overlay.

void remove(View view)

Removes the specified View from the overlay.

Inherited methods

void add(Drawable drawable)

Adds a Drawable to the overlay.

void clear()

Removes all content from the overlay.

void remove(Drawable drawable)

Removes the specified Drawable from the overlay.

Object clone()

Creates and returns a copy of this object.

boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

void finalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

final Class<?> getClass()

Returns the runtime class of this Object.

int hashCode()

Returns a hash code value for the object.

final void notify()

Wakes up a single thread that is waiting on this object's monitor.

final void notifyAll()

Wakes up all threads that are waiting on this object's monitor.

String toString()

Returns a string representation of the object.

final void wait(long timeoutMillis, int nanos)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait(long timeoutMillis)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait()

Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public methods

add

Added in API level 18
public void add (View view)

Adds a View to the overlay. The bounds of the added view should be relative to the host view. Any view added to the overlay should be removed when it is no longer needed or no longer visible.

Views in the overlay are visual-only; they do not receive input events and do not participate in focus traversal. Overlay views are intended to be transient, such as might be needed by a temporary animation effect.

If the view has a parent, the view will be removed from that parent before being added to the overlay. Also, if that parent is attached in the current view hierarchy, the view will be repositioned such that it is in the same relative location inside the activity. For example, if the view's current parent lies 100 pixels to the right and 200 pixels down from the origin of the overlay's host view, then the view will be offset by (100, 200).

Views added with this API will be drawn in the order they were added. Drawing of the overlay views will happen before drawing of any of the Drawables added with ViewOverlay.add(android.graphics.drawable.Drawable) API even if a call to this API happened after the call to ViewOverlay.add(android.graphics.drawable.Drawable).

Passing null parameter will result in an IllegalArgumentException being thrown.

Parameters
view View: The View to be added to the overlay. The added view will be drawn when the overlay is drawn. This value cannot be null.

remove

Added in API level 18
public void remove (View view)

Removes the specified View from the overlay. Passing null parameter will result in an IllegalArgumentException being thrown.

Parameters
view View: The View to be removed from the overlay. This value cannot be null.