com.atakmap.android.control

Class ScaleGestureDetector

java.lang.Object

com.atakmap.android.control.ScaleGestureDetector

public class ScaleGestureDetector
extends java.lang.Object

Detects transformation gestures involving more than one pointer ("multitouch") using the supplied MotionEvents. The ScaleGestureDetector.OnScaleGestureListener callback will notify users when a particular gesture event has occurred. This class should only be used with MotionEvents reported via touch. To use this class:

• Create an instance of the ScaleGestureDetector for your View
• In the View.onTouchEvent(MotionEvent) method ensure you call onTouchEvent(MotionEvent). The methods defined in your callback will be executed when the events occur.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ScaleGestureDetector.OnScaleGestureListener The listener for receiving notifications when gestures occur.
static class	ScaleGestureDetector.SimpleOnScaleGestureListener A convenience class to extend when you only want to listen for a subset of scaling-related events.

Constructor Summary

Constructors

Constructor and Description
ScaleGestureDetector(android.content.Context context, ScaleGestureDetector.OnScaleGestureListener listener)

Method Summary

Modifier and Type	Method and Description
double	getAngle()
android.view.MotionEvent	getEvent()
long	getEventTime() Return the event time of the current event being processed.
float	getFocusX() Get the X coordinate of the current gesture's focal point.
float	getFocusY() Get the Y coordinate of the current gesture's focal point.
android.view.MotionEvent	getPreviousEvent()
float	getScaleFactor() Return the scaling factor from the previous scale event to the current event.
android.view.MotionEvent	getStartEvent()
long	getTimeDelta() Return the time difference in milliseconds between the previous accepted scaling event and the current scaling event.
boolean	isInProgress() Returns true if a two-finger scale gesture is in progress.
boolean	onTouchEvent(android.view.MotionEvent event)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ScaleGestureDetector

public ScaleGestureDetector(android.content.Context context,
                            ScaleGestureDetector.OnScaleGestureListener listener)

Method Detail

onTouchEvent

public boolean onTouchEvent(android.view.MotionEvent event)

getAngle

public double getAngle()

isInProgress

public boolean isInProgress()

Returns true if a two-finger scale gesture is in progress.

Returns:

true if a scale gesture is in progress, false otherwise.

getFocusX

public float getFocusX()

Get the X coordinate of the current gesture's focal point. If a gesture is in progress, the focal point is directly between the two pointers forming the gesture. If a gesture is ending, the focal point is the location of the remaining pointer on the screen. If isInProgress() would return false, the result of this function is undefined.

Returns:

X coordinate of the focal point in pixels.

getFocusY

public float getFocusY()

Get the Y coordinate of the current gesture's focal point. If a gesture is in progress, the focal point is directly between the two pointers forming the gesture. If a gesture is ending, the focal point is the location of the remaining pointer on the screen. If isInProgress() would return false, the result of this function is undefined.

Returns:

Y coordinate of the focal point in pixels.

getScaleFactor

public float getScaleFactor()

Return the scaling factor from the previous scale event to the current event. This value is defined as (getCurrentSpan() / getPreviousSpan()).

Returns:

The current scaling factor.

getTimeDelta

public long getTimeDelta()

Return the time difference in milliseconds between the previous accepted scaling event and the current scaling event.

Returns:

Time difference since the last scaling event in milliseconds.

getEventTime

public long getEventTime()

Return the event time of the current event being processed.

Returns:

Current event time in milliseconds.

getEvent

public android.view.MotionEvent getEvent()

getStartEvent

public android.view.MotionEvent getStartEvent()

getPreviousEvent

public android.view.MotionEvent getPreviousEvent()