com.androidplot.xy

Class PanZoom

java.lang.Object

com.androidplot.xy.PanZoom

All Implemented Interfaces:

android.view.View.OnTouchListener

public class PanZoom
extends Object
implements android.view.View.OnTouchListener

Enables basic pan/zoom touch behavior for an XYPlot. By default boundaries there are no boundaries imposed on scrolling and zooming. You can provide these boundaries on your XYPlot using XYPlot.getOuterLimits(). TODO: zoom using dynamic center point TODO: stretch both mode

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	PanZoom.DragState
static class	PanZoom.Pan
static class	PanZoom.Zoom

Field Summary

Fields

Modifier and Type	Field and Description
protected android.graphics.RectF	fingersRect
protected static int	FIRST_FINGER
protected static float	MIN_DIST_2_FING
protected static int	SECOND_FINGER

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PanZoom(XYPlot plot, PanZoom.Pan pan, PanZoom.Zoom zoom)

Method Summary

Modifier and Type	Method and Description
static PanZoom	attach(XYPlot plot) Convenience method for enabling pan/zoom behavior on an instance of XYPlot, using a default behavior of PanZoom.Pan.BOTH and PanZoom.Zoom.SCALE.
static PanZoom	attach(XYPlot plot, PanZoom.Pan pan, PanZoom.Zoom zoom)
protected void	calculatePan(android.graphics.PointF oldFirstFinger, Region bounds, boolean horizontal)
protected void	calculateZoom(android.graphics.RectF newRect, float scale, boolean isHorizontal)
protected android.graphics.RectF	fingerDistance(float firstFingerX, float firstFingerY, float secondFingerX, float secondFingerY) Calculates the distance between two finger motion events.
protected android.graphics.RectF	fingerDistance(android.view.MotionEvent evt) Calculates the distance between two finger motion events.
android.view.View.OnTouchListener	getDelegate()
protected android.graphics.RectF	getFingersRect()
PanZoom.Pan	getPan()
PanZoom.Zoom	getZoom()
boolean	isEnabled()
protected boolean	isValidScale(float scale)
boolean	onTouch(android.view.View view, android.view.MotionEvent event)
protected void	pan(android.view.MotionEvent motionEvent)
void	reset()
void	setDelegate(android.view.View.OnTouchListener delegate) Set a delegate to receive onTouch calls before this class does.
void	setEnabled(boolean enabled)
protected void	setFingersRect(android.graphics.RectF fingersRect)
void	setPan(PanZoom.Pan pan)
void	setZoom(PanZoom.Zoom zoom)
protected void	zoom(android.view.MotionEvent motionEvent)

Methods inherited from class java.lang.Object

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

Field Detail

MIN_DIST_2_FING

protected static final float MIN_DIST_2_FING

See Also:

Constant Field Values

FIRST_FINGER

protected static final int FIRST_FINGER

See Also:

Constant Field Values

SECOND_FINGER

protected static final int SECOND_FINGER

See Also:

Constant Field Values

fingersRect

protected android.graphics.RectF fingersRect

Constructor Detail

PanZoom

protected PanZoom(XYPlot plot,
                  PanZoom.Pan pan,
                  PanZoom.Zoom zoom)

Method Detail

attach

public static PanZoom attach(XYPlot plot)

Convenience method for enabling pan/zoom behavior on an instance of XYPlot, using a default behavior of PanZoom.Pan.BOTH and PanZoom.Zoom.SCALE. Use attach(XYPlot, Pan, Zoom) for finer grain control of this behavior.

Parameters:

plot -

Returns:

attach

public static PanZoom attach(XYPlot plot,
                             PanZoom.Pan pan,
                             PanZoom.Zoom zoom)

isEnabled

public boolean isEnabled()

setEnabled

public void setEnabled(boolean enabled)

onTouch

public boolean onTouch(android.view.View view,
                       android.view.MotionEvent event)

Specified by:

onTouch in interface android.view.View.OnTouchListener

fingerDistance

protected android.graphics.RectF fingerDistance(float firstFingerX,
                                                float firstFingerY,
                                                float secondFingerX,
                                                float secondFingerY)

Calculates the distance between two finger motion events.

Parameters:

firstFingerX -

firstFingerY -

secondFingerX -

secondFingerY -

Returns:

fingerDistance

protected android.graphics.RectF fingerDistance(android.view.MotionEvent evt)

Calculates the distance between two finger motion events.

Parameters:

evt -

Returns:

pan

protected void pan(android.view.MotionEvent motionEvent)

calculatePan

protected void calculatePan(android.graphics.PointF oldFirstFinger,
                            Region bounds,
                            boolean horizontal)

isValidScale

protected boolean isValidScale(float scale)

zoom

protected void zoom(android.view.MotionEvent motionEvent)

calculateZoom

protected void calculateZoom(android.graphics.RectF newRect,
                             float scale,
                             boolean isHorizontal)

Parameters:

newRect - RectF into which zoom calculation results should be placed.

scale -

isHorizontal -

getPan

public PanZoom.Pan getPan()

setPan

public void setPan(PanZoom.Pan pan)

getZoom

public PanZoom.Zoom getZoom()

setZoom

public void setZoom(PanZoom.Zoom zoom)

getDelegate

public android.view.View.OnTouchListener getDelegate()

setDelegate

public void setDelegate(android.view.View.OnTouchListener delegate)

Set a delegate to receive onTouch calls before this class does. If the delegate wishes to consume the event, it should return true, otherwise it should return false. Returning false will not prevent future onTouch events from filtering through the delegate as it normally would when attaching directly to an instance of View.

Parameters:

delegate -

reset

public void reset()

getFingersRect

protected android.graphics.RectF getFingersRect()

setFingersRect

protected void setFingersRect(android.graphics.RectF fingersRect)