javafx.scene.canvas

Class Canvas

java.lang.Object

Node

javafx.scene.canvas.Canvas

public class Canvas
extends Node

Canvas is an image that can be drawn on using a set of graphics commands provided by a GraphicsContext.

A Canvas node is constructed with a width and height that specifies the size of the image into which the canvas drawing commands are rendered. All drawing operations are clipped to the bounds of that image.

Example:

import javafx.scene.*;
import javafx.scene.paint.*;
import javafx.scene.canvas.*;

Group root = new Group();
Scene s = new Scene(root, 300, 300, Color.BLACK);

final Canvas canvas = new Canvas(250,250);
GraphicsContext gc = canvas.getGraphicsContext2D();

gc.setFill(Color.BLUE);
gc.fillRect(75,75,100,100);

root.getChildren().add(canvas);
 

Since:

JavaFX 2.2

See Also:

GraphicsContext

Property Summary

Type	Property and Description
DoubleProperty	height Defines the height of the canvas.
DoubleProperty	width Defines the width of the canvas.

Field Summary

Fields

Modifier and Type	Field and Description
private GrowableDataBuffer	current
(package private) static int	DEFAULT_OBJ_BUF_SIZE
(package private) static int	DEFAULT_VAL_BUF_SIZE
private DoubleProperty	height Defines the height of the canvas.
private int	lastsizeindex
private int[]	recentobjsizes
private int[]	recentvalsizes
private boolean	rendererBehind
private static int	SIZE_HISTORY
private GraphicsContext	theContext
private DoubleProperty	width Defines the width of the canvas.

Constructor Summary

Constructors

Constructor and Description
Canvas() Creates an empty instance of Canvas.
Canvas(double width, double height) Creates a new instance of Canvas with the given size.

Method Summary

Modifier and Type	Method and Description
private boolean	doComputeContains(double localX, double localY)
private BaseBounds	doComputeGeomBounds(BaseBounds bounds, BaseTransform tx)
private NGNode	doCreatePeer()
private void	doUpdatePeer()
(package private) GrowableDataBuffer	getBuffer()
GraphicsContext	getGraphicsContext2D() returns the GraphicsContext associated with this Canvas.
double	getHeight() Gets the value of the property height.
double	getWidth() Gets the value of the property width.
DoubleProperty	heightProperty() Defines the height of the canvas.
(package private) boolean	isRendererFallingBehind()
private static int	max(int[] sizes, int defsize)
void	setHeight(double value) Sets the value of the property height.
void	setWidth(double value) Sets the value of the property width.
DoubleProperty	widthProperty() Defines the width of the canvas.

Methods inherited from class java.lang.Object

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

Property Detail

width

public final DoubleProperty widthProperty

Defines the width of the canvas.

See Also:

getWidth(), setWidth(double)

height

public final DoubleProperty heightProperty

Defines the height of the canvas.

See Also:

getHeight(), setHeight(double)

Field Detail

DEFAULT_VAL_BUF_SIZE

static final int DEFAULT_VAL_BUF_SIZE

See Also:

Constant Field Values

DEFAULT_OBJ_BUF_SIZE

static final int DEFAULT_OBJ_BUF_SIZE

See Also:

Constant Field Values

SIZE_HISTORY

private static final int SIZE_HISTORY

See Also:

Constant Field Values

current

private GrowableDataBuffer current

rendererBehind

private boolean rendererBehind

recentvalsizes

private int[] recentvalsizes

recentobjsizes

private int[] recentobjsizes

lastsizeindex

private int lastsizeindex

theContext

private GraphicsContext theContext

width

private DoubleProperty width

Defines the width of the canvas.

height

private DoubleProperty height

Defines the height of the canvas.

Constructor Detail

Canvas

public Canvas()

Creates an empty instance of Canvas.

Canvas

public Canvas(double width,
              double height)

Creates a new instance of Canvas with the given size.

Parameters:

width - width of the canvas

height - height of the canvas

Method Detail

max

private static int max(int[] sizes,
                       int defsize)

getBuffer

GrowableDataBuffer getBuffer()

isRendererFallingBehind

boolean isRendererFallingBehind()

getGraphicsContext2D

public GraphicsContext getGraphicsContext2D()

returns the GraphicsContext associated with this Canvas.

Returns:

the GraphicsContext associated with this Canvas

setWidth

public final void setWidth(double value)

Sets the value of the property width.

getWidth

public final double getWidth()

Gets the value of the property width.

widthProperty

public final DoubleProperty widthProperty()

Defines the width of the canvas.

See Also:

getWidth(), setWidth(double)

setHeight

public final void setHeight(double value)

Sets the value of the property height.

getHeight

public final double getHeight()

Gets the value of the property height.

heightProperty

public final DoubleProperty heightProperty()

Defines the height of the canvas.

See Also:

getHeight(), setHeight(double)

doCreatePeer

private NGNode doCreatePeer()

doUpdatePeer

private void doUpdatePeer()

doComputeContains

private boolean doComputeContains(double localX,
                                  double localY)

doComputeGeomBounds

private BaseBounds doComputeGeomBounds(BaseBounds bounds,
                                       BaseTransform tx)