de.mrapp.android.util.gesture

Class DragHelper

java.lang.Object

de.mrapp.android.util.gesture.DragHelper

public class DragHelper
extends java.lang.Object

A helper class, which may be used to recognize drag gestures.

Since:

1.4.0

Constructor Summary

Constructors

Constructor and Description
DragHelper(int threshold) Creates a new helper class, which may be used to recognize drag gestures.

Method Summary

Modifier and Type	Method and Description
int	getDistance() Returns the distance, which has been passed while dragging, in pixels.
float	getDragSpeed() Returns the speed of the drag gesture in pixels per millisecond.
int	getStartPosition() Returns the position, where the gesture has been started at.
boolean	hasThresholdBeenReached() Returns, whether the threshold has already been reached, or not.
boolean	isReseted() Returns, whether the instance has been marked to be reseted, since the method update(float):void has been called the last time.
void	reset() Marks the instance to be reseted.
void	update(float position) Updates the instance by adding a new position.

Methods inherited from class java.lang.Object

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

Constructor Detail

DragHelper

public DragHelper(int threshold)

Creates a new helper class, which may be used to recognize drag gestures.

Parameters:

threshold - The distance in pixels, the gesture must last until it is recognized, as an Integer value. The value must be at least 0

Method Detail

reset

public final void reset()

Marks the instance to be reseted. This will cause all properties to be reseted to default values, when a value is added by calling the method update(float):void the next time. Therefore this method may be used to start recognizing a new drag gesture, whenever a value is added the next time, while the values of the previous recognition can be still retrieved until recognizing the new gesture begins.

isReseted

public final boolean isReseted()

Returns, whether the instance has been marked to be reseted, since the method update(float):void has been called the last time. See method reset():void for further information.

Returns:

True, if the instance has been marked to be reseted, false otherwise

update

public final void update(float position)

Updates the instance by adding a new position. This will cause all properties to be re-calculated, depending on the new position.

Parameters:

position - The position, which should be added, as a Float value

hasThresholdBeenReached

public final boolean hasThresholdBeenReached()

Returns, whether the threshold has already been reached, or not.

Returns:

True, if the threshold has been already reached, false otherwise

getDistance

public final int getDistance()

Returns the distance, which has been passed while dragging, in pixels.

Returns:

The distance, which has been passed while dragging, as an Integer value or 0, if the threshold has not been reached yet

getStartPosition

public final int getStartPosition()

Returns the position, where the gesture has been started at.

Returns:

The position, where the gesture has been started at, as an Integer value or -1, if no gesture has been started yet

getDragSpeed

public final float getDragSpeed()

Returns the speed of the drag gesture in pixels per millisecond.

Returns:

The speed of the drag gesture as a Float value or -1, if the threshold has not been reached yet