org.pepstock.charba.client

Class Helpers

java.lang.Object

org.pepstock.charba.client.Helpers

public final class Helpers
extends Object

Singleton object to use the helpers utility of CHART.JS.
It maps the java script object chart.helpers.

Author:

Andrea "Stock" Stocchero

Method Summary

Modifier and Type	Method and Description
void	clipArea(Canvas canvas, double width, double height) Clips an area on the canvas context, using the Context2dItem of the canvas. The area is specified by size. Starting points are 0.
void	clipArea(Canvas canvas, double x, double y, double width, double height) Clips an area on the canvas context, using the Context2dItem of the canvas. The area is specified by coordinates and size.
void	clipArea(Canvas canvas, IsArea area) Clips an area on the canvas context, using the Context2dItem of the canvas.
void	clipArea(Context2dItem context, double width, double height) Clips an area on the canvas context. The area is specified by size. Starting points are 0.
void	clipArea(Context2dItem context, double x, double y, double width, double height) Clips an area on the canvas context. The area is specified by coordinates and size.
void	clipArea(Context2dItem context, IsArea area) Clips an area on the canvas context.
void	clipArea(IsChart chart) Clips an area on the canvas context using the ChartAreaNode of the chart.
void	clipArea(IsChart chart, double width, double height) Clips an area on the canvas context, using the Canvas of the chart. The area is specified by size. Starting points are 0.
void	clipArea(IsChart chart, double x, double y, double width, double height) Clips an area on the canvas context, using the Canvas of the chart. The area is specified by coordinates and size.
void	clipArea(IsChart chart, IsArea area) Clips an area on the canvas context, using the Canvas of the chart.
NativeObject	clone(NativeObject source) Returns a deep copy of source without keeping references on objects and arrays.
static Helpers	get() Singleton method to get the instance
EventPoint	getRelativePosition(ChartEventContext eventContext) A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred.
EventPoint	getRelativePosition(IsChart chart, AbstractEvent event) A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred.
EventPoint	getRelativePosition(IsChart chart, BaseNativeEvent event) A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred.
NativeObject	mergeIf(NativeObject target, NativeObject source) Recursively deep copies source properties in the target only if not defined in target. IMPORTANT: target is not cloned and will be updated with source properties.
IsImmutableFont	toFont(FontItem font) Parses font options and returns a normalized font object.
IsImmutableFont	toFont(IsDefaultFont font) Parses font options and returns a normalized font object.
String	toFontString(FontItem font) Builds the font string (shorthand property of CSS font) to use in the canvas object. See here CSS specification.
String	toFontString(IsDefaultFont font) Builds the font string (shorthand property of CSS font) to use in the canvas object. See here CSS specification.
void	unclipArea(Context2dItem context) Unclips the area previously set.

Methods inherited from class java.lang.Object

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

Method Detail

get

public static Helpers get()

Singleton method to get the instance

Returns:

helper instance

mergeIf

public NativeObject mergeIf(NativeObject target,
                            NativeObject source)

Recursively deep copies source properties in the target only if not defined in target.
IMPORTANT: target is not cloned and will be updated with source properties.

Parameters:

target - the target object in which all sources are merged into.

source - object to merge in the target.

Returns:

the target object. If target and source are nulls, an empty native object is returned is returned.

clone

public NativeObject clone(NativeObject source)

Returns a deep copy of source without keeping references on objects and arrays.

Parameters:

source - the object to clone.

Returns:

a clone of source object

getRelativePosition

public EventPoint getRelativePosition(ChartEventContext eventContext)

A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred. It provides the relative point on canvas.

Parameters:

eventContext - event context to be used for getting the point.

Returns:

a point object

getRelativePosition

public EventPoint getRelativePosition(IsChart chart,
                                      AbstractEvent event)

A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred. It provides the relative point on canvas.

Parameters:

chart - chart instance

event - native event to be used for getting the point.

Returns:

a point object

getRelativePosition

public EventPoint getRelativePosition(IsChart chart,
                                      BaseNativeEvent event)

A common occurrence is taking an event, such as a click, and finding the data coordinates on the chart where the event occurred. It provides the relative point on canvas.

Parameters:

chart - chart instance

event - native event to be used for getting the point.

Returns:

a point object

toFont

public IsImmutableFont toFont(IsDefaultFont font)

Parses font options and returns a normalized font object.

Parameters:

font - a object that contains font options to be parsed.

Returns:

a font object

toFont

public IsImmutableFont toFont(FontItem font)

Parses font options and returns a normalized font object.

Parameters:

font - a object that contains font options to be parsed.

Returns:

a font object

toFontString

public String toFontString(IsDefaultFont font)

Builds the font string (shorthand property of CSS font) to use in the canvas object.
See here CSS specification.

Parameters:

font - a object that contains font options to be parsed.

Returns:

the font string to use in the canvas object.

toFontString

public String toFontString(FontItem font)

Builds the font string (shorthand property of CSS font) to use in the canvas object.
See here CSS specification.

Parameters:

font - a object that contains font options to be parsed.

Returns:

the font string to use in the canvas object.

clipArea

public void clipArea(IsChart chart)

Clips an area on the canvas context using the ChartAreaNode of the chart.

Parameters:

chart - chart instance

clipArea

public void clipArea(IsChart chart,
                     IsArea area)

Clips an area on the canvas context, using the Canvas of the chart.

Parameters:

chart - chart instance

area - area to clip on the context

clipArea

public void clipArea(IsChart chart,
                     double width,
                     double height)

Clips an area on the canvas context, using the Canvas of the chart.
The area is specified by size.
Starting points are 0.

Parameters:

chart - chart instance

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

clipArea

public void clipArea(IsChart chart,
                     double x,
                     double y,
                     double width,
                     double height)

Clips an area on the canvas context, using the Canvas of the chart.
The area is specified by coordinates and size.

Parameters:

chart - chart instance

x - the x-axis coordinate of the rectangle's starting point

y - the y-axis coordinate of the rectangle's starting point

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

clipArea

public void clipArea(Canvas canvas,
                     IsArea area)

Clips an area on the canvas context, using the Context2dItem of the canvas.

Parameters:

canvas - canvas where to apply the clippping

area - area to clip on the context

clipArea

public void clipArea(Canvas canvas,
                     double width,
                     double height)

Clips an area on the canvas context, using the Context2dItem of the canvas.
The area is specified by size.
Starting points are 0.

Parameters:

canvas - canvas where to apply the clippping

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

clipArea

public void clipArea(Canvas canvas,
                     double x,
                     double y,
                     double width,
                     double height)

Clips an area on the canvas context, using the Context2dItem of the canvas.
The area is specified by coordinates and size.

Parameters:

canvas - canvas where to apply the clippping

x - the x-axis coordinate of the rectangle's starting point

y - the y-axis coordinate of the rectangle's starting point

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

clipArea

public void clipArea(Context2dItem context,
                     IsArea area)

Clips an area on the canvas context.

Parameters:

context - context of the canvas

area - area to clip on the context

clipArea

public void clipArea(Context2dItem context,
                     double width,
                     double height)

Clips an area on the canvas context.
The area is specified by size.
Starting points are 0.

Parameters:

context - context of the canvas

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

clipArea

public void clipArea(Context2dItem context,
                     double x,
                     double y,
                     double width,
                     double height)

Clips an area on the canvas context.
The area is specified by coordinates and size.

Parameters:

context - context of the canvas

x - the x-axis coordinate of the rectangle's starting point

y - the y-axis coordinate of the rectangle's starting point

width - the rectangle's width. Positive values are to the right, and negative to the left

height - the rectangle's height. Positive values are down, and negative are up

unclipArea

public void unclipArea(Context2dItem context)

Unclips the area previously set.

Parameters:

context - context of the canvas where an area has been clipped.