Package org.pepstock.charba.client.colors

Class CanvasObjectFactory

java.lang.Object

org.pepstock.charba.client.colors.CanvasObjectFactory

Direct Known Subclasses:

DatasetCanvasObjectFactory

public abstract class CanvasObjectFactory
extends Object

Abstract utility class which creates a canvas gradient and pattern java script objects using a Charba gradient or pattern.
A Charba gradient or pattern describes how a canvas gradient or pattern must be created.

Author:

Andrea "Stock" Stocchero

See Also:

Gradient, Pattern, CanvasGradientItem, CanvasPatternItem

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CanvasObjectFactory(Key scope)	Creates the object using the scope of this factory.

Method Summary

Modifier and Type	Method	Description
void	clear(IsChart chart)	Clears the cache of loaded patterns and gradients, needed when a chart is destroy.
CanvasGradientItem	createGradient(IsChart chart, Gradient gradient, int datasetIndex)	Creates a canvas gradient java script object using a Charba gradient and a chart instance which must provide a canvas instance and its context.
CanvasPatternItem	createPattern(IsChart chart, Pattern pattern)	Creates a canvas pattern java script object using a Charba pattern and a chart instance which must provide a canvas instance and its context.
protected abstract Area	getArea(IsChart chart, Gradient gradient)	Returns an area object used to define the area of LINEAR gradient.
protected abstract Center	getCenter(IsChart chart, Gradient gradient, int datasetIndex)	Returns the coordinates of a center of arc for RADIAL gradient.
protected abstract Radius	getRadius(IsChart chart, Gradient gradient, int datasetIndex)	Returns the inner and outer radius of arc for RADIAL gradient.
Key	getScope()	Returns the scope of this factory.
void	resetGradients(IsChart chart)	Removes from cache all loaded gradients, needed during the resize of chart.

Methods inherited from class java.lang.Object

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

Constructor Detail

CanvasObjectFactory

protected CanvasObjectFactory(Key scope)

Creates the object using the scope of this factory.

Parameters:

scope - scope of this factory

Method Detail

getScope

public final Key getScope()

Returns the scope of this factory.

Returns:

the scope of this factory

createPattern

public final CanvasPatternItem createPattern(IsChart chart,
                                             Pattern pattern)

Creates a canvas pattern java script object using a Charba pattern and a chart instance which must provide a canvas instance and its context.

Parameters:

chart - chart instance which must provide a canvas instance and its context

pattern - pattern instance created at configuration level

Returns:

a canvas pattern

resetGradients

public final void resetGradients(IsChart chart)

Removes from cache all loaded gradients, needed during the resize of chart.

Parameters:

chart - chart instance on which removes all loaded gradients

clear

public final void clear(IsChart chart)

Clears the cache of loaded patterns and gradients, needed when a chart is destroy.

Parameters:

chart - chart instance on which removes all loaded objects.

createGradient

public final CanvasGradientItem createGradient(IsChart chart,
                                               Gradient gradient,
                                               int datasetIndex)

Creates a canvas gradient java script object using a Charba gradient and a chart instance which must provide a canvas instance and its context.

Parameters:

chart - chart instance which must provide a canvas instance and its context

gradient - gradient instance created at configuration level

datasetIndex - data set index

Returns:

a canvas gradient

getArea

protected abstract Area getArea(IsChart chart,
                                Gradient gradient)

Returns an area object used to define the area of LINEAR gradient.

Parameters:

chart - chart instance

gradient - gradient instance

Returns:

an area object used to define the area of LINEAR gradient

getCenter

protected abstract Center getCenter(IsChart chart,
                                    Gradient gradient,
                                    int datasetIndex)

Returns the coordinates of a center of arc for RADIAL gradient.

Parameters:

chart - chart instance

gradient - gradient instance

datasetIndex - data set index

Returns:

the coordinates of a center of arc

getRadius

protected abstract Radius getRadius(IsChart chart,
                                    Gradient gradient,
                                    int datasetIndex)

Returns the inner and outer radius of arc for RADIAL gradient.

Parameters:

chart - chart instance

gradient - gradient instance

datasetIndex - data set index

Returns:

the inner and outer radius of arc