Added in API level 8

ScaleGestureDetector.SimpleOnScaleGestureListener


public static class ScaleGestureDetector.SimpleOnScaleGestureListener
extends Object implements ScaleGestureDetector.OnScaleGestureListener

java.lang.Object
   ↳ android.view.ScaleGestureDetector.SimpleOnScaleGestureListener


A convenience class to extend when you only want to listen for a subset of scaling-related events. This implements all methods in OnScaleGestureListener but does nothing. OnScaleGestureListener#onScale(ScaleGestureDetector) returns false so that a subclass can retrieve the accumulated scale factor in an overridden onScaleEnd. OnScaleGestureListener#onScaleBegin(ScaleGestureDetector) returns true.

Summary

Public constructors

SimpleOnScaleGestureListener()

Public methods

boolean onScale(ScaleGestureDetector detector)

Responds to scaling events for a gesture in progress.

boolean onScaleBegin(ScaleGestureDetector detector)

Responds to the beginning of a scaling gesture.

void onScaleEnd(ScaleGestureDetector detector)

Responds to the end of a scale gesture.

Inherited methods

Public constructors

SimpleOnScaleGestureListener

public SimpleOnScaleGestureListener ()

Public methods

onScale

Added in API level 8
public boolean onScale (ScaleGestureDetector detector)

Responds to scaling events for a gesture in progress. Reported by pointer motion.

Parameters
detector ScaleGestureDetector: This value cannot be null.

Returns
boolean Whether or not the detector should consider this event as handled. If an event was not handled, the detector will continue to accumulate movement until an event is handled. This can be useful if an application, for example, only wants to update scaling factors if the change is greater than 0.01.

onScaleBegin

Added in API level 8
public boolean onScaleBegin (ScaleGestureDetector detector)

Responds to the beginning of a scaling gesture. Reported by new pointers going down.

Parameters
detector ScaleGestureDetector: This value cannot be null.

Returns
boolean Whether or not the detector should continue recognizing this gesture. For example, if a gesture is beginning with a focal point outside of a region where it makes sense, onScaleBegin() may return false to ignore the rest of the gesture.

onScaleEnd

Added in API level 8
public void onScaleEnd (ScaleGestureDetector detector)

Responds to the end of a scale gesture. Reported by existing pointers going up. Once a scale has ended, ScaleGestureDetector#getFocusX() and ScaleGestureDetector#getFocusY() will return focal point of the pointers remaining on the screen.

Parameters
detector ScaleGestureDetector: This value cannot be null.