public class BarChart

Renders a bar chart based on an XYMultipleSeriesDataset.

Create an instance together with a matching XYMultipleSeriesRenderer and wrap it in a com.codename1.charts.ChartComponent to display it in the UI. A minimal setup looks like this:

XYMultipleSeriesDataset dataset = new XYMultipleSeriesDataset();
dataset.addSeries(mySeries);

XYMultipleSeriesRenderer renderer = new XYMultipleSeriesRenderer();
renderer.addSeriesRenderer(new XYSeriesRenderer());

BarChart chart = new BarChart(dataset, renderer, BarChart.Type.DEFAULT);
Form form = new Form(new BorderLayout());
form.add(BorderLayout.CENTER, new ChartComponent(chart));
form.show();

The Type supplied to the constructor controls whether the bars are rendered in their default style, stacked or heaped.

Nested types

enum BarChart.Type The bar chart type enum.

Fields

`public static final` `String TYPE = "Bar"`	The constant to identify this chart type.
`protected` `BarChart.Type mType`	The chart type.

Constructors

public BarChart(XYMultipleSeriesDataset dataset, XYMultipleSeriesRenderer renderer, BarChart.Type type) Builds a new bar chart instance.

Methods

`protected` `ClickableArea[] clickableAreasForPoints(List<Float> points, List<Double> values, float yAxisValue, int seriesIndex, int startIndex)`	Returns the clickable areas for all passed points
`public void drawSeries(Canvas canvas, Paint paint, List<Float> points, XYSeriesRenderer seriesRenderer, float yAxisValue, int seriesIndex, int startIndex)`	The graphical representation of a series.
`protected void drawBar(Canvas canvas, float xMin, float yMin, float xMax, float yMax, float halfDiffX, int seriesNr, int seriesIndex, Paint paint)`	Draws a bar.
`protected void drawBar(Canvas canvas, float xMin, float yMin, float xMax, float yMax, int scale, int seriesIndex, Paint paint)`	Draws a bar.
`protected int getGradientPartialColor(int minColor, int maxColor, float fraction)`
`protected void drawChartValuesText(Canvas canvas, XYSeries series, XYSeriesRenderer renderer, Paint paint, List<Float> points, int seriesIndex, int startIndex)`	The graphical representation of the series values as text.
`public int getLegendShapeWidth(int seriesIndex)`	Returns the legend shape width.
`public void drawLegendShape(Canvas canvas, SimpleSeriesRenderer renderer, float x, float y, int seriesIndex, Paint paint)`	The graphical representation of the legend shape.
`protected float getHalfDiffX(List<Float> points, int length, int seriesNr)`	Calculates and returns the half-distance in the graphical representation of 2 consecutive points.
`protected float getCoeficient()`	Returns the value of a constant used to calculate the half-distance.
`protected boolean isRenderNullValues()`	Returns if the chart should display the null values.
`public double getDefaultMinimum()`	Returns the default axis minimum.
`public` `String getChartType()`	Returns the chart type identifier.

Inherited fields

From XYChart

mDataset, mRenderer

Inherited methods

From AbstractChart

calculateDrawPoints, drawBackground, drawLegend, drawString, getExceed, isVertical, getLabel, drawPath, drawPath, getLegendSize, drawLabel, isNullValue

From Object

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

Field details

TYPE

public static final String TYPE = "Bar"

The constant to identify this chart type.

mType

protected BarChart.Type mType

The chart type.

Constructor details

BarChart

public BarChart(XYMultipleSeriesDataset dataset, XYMultipleSeriesRenderer renderer, BarChart.Type type)

Builds a new bar chart instance.

Parameters

dataset XYMultipleSeriesDataset: the multiple series dataset
renderer XYMultipleSeriesRenderer: the multiple series renderer
type BarChart.Type: the bar chart type

Method details

clickableAreasForPoints

protected ClickableArea[] clickableAreasForPoints(List<Float> points, List<Double> values, float yAxisValue, int seriesIndex, int startIndex)

Returns the clickable areas for all passed points

Parameters

points List<Float>: the array of points
values List<Double>: the array of values of each point
yAxisValue float: the minimum value of the y axis
seriesIndex int: the index of the series to which the points belong
startIndex int: the start index of the rendering points

Returns

an array of rectangles with the clickable area

drawSeries

public void drawSeries(Canvas canvas, Paint paint, List<Float> points, XYSeriesRenderer seriesRenderer, float yAxisValue, int seriesIndex, int startIndex)

The graphical representation of a series.

Parameters

canvas Canvas: the canvas to paint to
paint Paint: the paint to be used for drawing
points List<Float>: the array of points to be used for drawing the series
seriesRenderer XYSeriesRenderer: the series renderer
yAxisValue float: the minimum value of the y axis
seriesIndex int: the index of the series currently being drawn
startIndex int: the start index of the rendering points

drawBar

protected void drawBar(Canvas canvas, float xMin, float yMin, float xMax, float yMax, float halfDiffX, int seriesNr, int seriesIndex, Paint paint)

Draws a bar.

Parameters

canvas Canvas: the canvas
xMin float: the X axis minimum
yMin float: the Y axis minimum
xMax float: the X axis maximum
yMax float: the Y axis maximum
halfDiffX float: half the size of a bar
seriesNr int: the total number of series
seriesIndex int: the current series index
paint Paint: the paint

drawBar

protected void drawBar(Canvas canvas, float xMin, float yMin, float xMax, float yMax, int scale, int seriesIndex, Paint paint)

Draws a bar.

Parameters

canvas Canvas: the canvas
xMin float: the X axis minimum
yMin float: the Y axis minimum
xMax float: the X axis maximum
yMax float: the Y axis maximum
scale int: the scale index
seriesIndex int: the current series index
paint Paint: the paint

getGradientPartialColor

protected int getGradientPartialColor(int minColor, int maxColor, float fraction)

drawChartValuesText

protected void drawChartValuesText(Canvas canvas, XYSeries series, XYSeriesRenderer renderer, Paint paint, List<Float> points, int seriesIndex, int startIndex)

The graphical representation of the series values as text.

Parameters

canvas Canvas: the canvas to paint to
series XYSeries: the series to be painted
renderer XYSeriesRenderer: the series renderer
paint Paint: the paint to be used for drawing
points List<Float>: the array of points to be used for drawing the series
seriesIndex int: the index of the series currently being drawn
startIndex int: the start index of the rendering points

getLegendShapeWidth

public int getLegendShapeWidth(int seriesIndex)

Returns the legend shape width.

Parameters

seriesIndex int: the series index

Returns

the legend shape width

drawLegendShape

public void drawLegendShape(Canvas canvas, SimpleSeriesRenderer renderer, float x, float y, int seriesIndex, Paint paint)

The graphical representation of the legend shape.

Parameters

canvas Canvas: the canvas to paint to
renderer SimpleSeriesRenderer: the series renderer
x float: the x value of the point the shape should be drawn at
y float: the y value of the point the shape should be drawn at
seriesIndex int: the series index
paint Paint: the paint to be used for drawing

getHalfDiffX

protected float getHalfDiffX(List<Float> points, int length, int seriesNr)

Calculates and returns the half-distance in the graphical representation of 2 consecutive points.

Parameters

points List<Float>: the points
length int: the points length
seriesNr int: the series number

Returns

the calculated half-distance value

getCoeficient

protected float getCoeficient()

Returns the value of a constant used to calculate the half-distance.

Returns

the constant value

isRenderNullValues

protected boolean isRenderNullValues()

Returns if the chart should display the null values.

Returns

if null values should be rendered

getDefaultMinimum

public double getDefaultMinimum()

Returns the default axis minimum.

Returns

the default axis minimum

getChartType

public String getChartType()

Returns the chart type identifier.

Returns

the chart type