SimpleOnScaleGestureListener

Kotlin |Java

open class SimpleOnScaleGestureListener : ScaleGestureDetector.OnScaleGestureListener

kotlin.Any
↳	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
open Boolean	`onScale(detector: ScaleGestureDetector)` Responds to scaling events for a gesture in progress.
open Boolean	`onScaleBegin(detector: ScaleGestureDetector)` Responds to the beginning of a scaling gesture.
open Unit	`onScaleEnd(detector: ScaleGestureDetector)` Responds to the end of a scale gesture.

SimpleOnScaleGestureListener()

open fun onScale(detector: ScaleGestureDetector): Boolean

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

Parameters
`detector`	ScaleGestureDetector: This value cannot be `null`.

Return
`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.

open fun onScaleBegin(detector: ScaleGestureDetector): Boolean

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

Parameters
`detector`	ScaleGestureDetector: This value cannot be `null`.

Return
`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.

open fun onScaleEnd(detector: ScaleGestureDetector): Unit

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`.