com.googlecode.gchart.client
Class GChart.Curve

java.lang.Object
  com.googlecode.gchart.client.GChart.Curve

Enclosing class:

GChart

public class GChart.Curve
extends java.lang.Object

Represents a curve on a chart, which includes information such as the x,y coordinates of each point, the symbol used to represent points on the curve, etc.

To create a new curve, use the GChart.addCurve method.

See Also:

addCurve()

Nested Class Summary

class

GChart.Curve.Point Represents a single point on one of the chart's curves.

Method Summary

void	addPoint(double x, double y) Adds a new point to the curve, at the end of the current list of points, with the specified coordinates in model-units (arbitrary, application-specific, units).
void	addPoint(int iPoint, double x, double y) Adds a new point at the specified position in the point sequence, increasing the indexes of existing points at or after the specified position by 1.
void	clearPoints() Removes every point this curve contains.
java.lang.String	getHovertextTemplate() Deprecated. This method is equivalent to: getSymbol().getHovertextTemplate() It is retained only for GChart 1.1 compatibility purposes.
java.lang.String	getLegendLabel() Returns the HTML defining this curve's legend label.
int	getNPoints() Returns the number of points this curve contains.
GChart	getParent() Returns a reference to the GChart that contains this curve.
GChart.Curve.Point	getPoint() Convenience method equivalent to getPoint(getNPoints()-1).
GChart.Curve.Point	getPoint(int iPoint) Returns a reference to the point at the specified index.
int	getPointIndex(GChart.Curve.Point point) Returns the positional index (within this curve's list of points) of the specified point.
GChart.Symbol	getSymbol() Returns the symbol associated with this curve.
com.googlecode.gchart.client.GChart.YAxisId	getYAxis() Returns the y-axis (Y_AXIS or Y2_AXIS) this curve is plotted on.
boolean	isVisible() Is this curve visible on the chart and legend key, or is it hidden from view.
boolean	onY2() Convenience method equivalent to getYAxis()==Y2_AXIS.
void	removePoint(GChart.Curve.Point p) Removes the given point from this curve.
void	removePoint(int iPoint) Removes the point at the specified index.
void	setHovertextTemplate(java.lang.String hovertextTemplate) Deprecated. This method is equivalent to: getSymbol().setHovertextTemplate(hovertextTemplate) It is retained only for GChart 1.1 compatibility purposes.
void	setLegendLabel(java.lang.String legendHTML) Sets the HTML that defines the label shown to the right of the icon representing the curve's symbol in the chart's legend.
void	setVisible(boolean isVisible) Defines if this curve is visible both in the plotting region and on the legend key.
void	setYAxis(com.googlecode.gchart.client.GChart.YAxisId axisId) Sets the y-axis that this curve is plotted on.

Methods inherited from class java.lang.Object

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

Method Detail

addPoint

public void addPoint(double x,
                     double y)

Adds a new point to the curve, at the end of the current list of points, with the specified coordinates in model-units (arbitrary, application-specific, units).

GChart gives a special interpretation to the following values:

1. If -Double.MAX_VALUE is specified for either x or y, the point acts as if it were placed at the minimum visible x or y position within the plot area.

2. Similarly, if Double.MAX_VALUE is specified for either x or y, the point acts as if it were placed at the maximum visible x or y position within the plot area.

3. If Double.NaN is specified for either x or y, the point is created, but it will not be visible in the charting region.

   Tip: Connecting lines to/from such Double.NaN points are elided, so you can use such a point to create a break in an otherwise connected curve.

Parameters:

x - the x-coordinate of the new point

y - the y-coordinate of the new point

See Also:

getPoint, addPoint(int,double,double), removePoint, clearPoints, getNPoints

addPoint

public void addPoint(int iPoint,
                     double x,
                     double y)

Adds a new point at the specified position in the point sequence, increasing the indexes of existing points at or after the specified position by 1.

Parameters:

iPoint - the position that the new point will occupy

x - the x-coordinate of the new point (model units)

y - the y-coordinate of the new point (model units)

See Also:

getPoint, addPoint(double,double), removePoint, clearPoints, getNPoints

clearPoints

public void clearPoints()

Removes every point this curve contains.

See Also:

Point, getPoint, addPoint(double,double), addPoint(int,double,double), removePoint, getNPoints

getHovertextTemplate

public java.lang.String getHovertextTemplate()

Deprecated. This method is equivalent to:

getSymbol().getHovertextTemplate()

It is retained only for GChart 1.1 compatibility purposes.

See Also:

Symbol.getHovertextTemplate

getLegendLabel

public java.lang.String getLegendLabel()

Returns the HTML defining this curve's legend label.

Returns:

the legend label HTML for this curve

See Also:

setLegendLabel

getNPoints

public int getNPoints()

Returns the number of points this curve contains.

Returns:

the number of points this curve contains.

See Also:

getPoint, addPoint(double,double), addPoint(int,double,double), removePoint, clearPoints

getParent

public GChart getParent()

Returns a reference to the GChart that contains this curve.

Returns:

GChart that contains this curve--its "parent".

getPoint

public GChart.Curve.Point getPoint()

Convenience method equivalent to getPoint(getNPoints()-1).

This method makes code more readable for the common case when you first add a point to the end of a curve, and then modify that point's attributes, as illustrated below:

   class MyChart extends GChart {
     public MyChart() {
       addCurve();
       for (int i=0; i < 10; i++) {
         getCurve().addPoint(i,i);
         getCurve().getPoint().setAnnotationText("Point " + i);
       }
       update();
     }
   }
 

Returns:

the point on the curve with the highest integer index

See Also:

getPoint(int), getNPoints()

getPoint

public GChart.Curve.Point getPoint(int iPoint)

Returns a reference to the point at the specified index. The returned reference can be used to modify various properties of the point, such as its optional annotation (text label).

Parameters:

iPoint - the index of the point to be returned.

Returns:

a reference to the Point at the specified index.

See Also:

addPoint(double,double), addPoint(int,double,double), removePoint, clearPoints, getNPoints

getPointIndex

public int getPointIndex(GChart.Curve.Point point)

Returns the positional index (within this curve's list of points) of the specified point.

Returns GChart.NAI if the specified point is not found on this curve's point list.

Parameters:

point - point whose list position is to be retrieved

Returns:

position of point on this curve's point list, or GChart.NAI if not on the list.

See Also:

getPoint(), getPoint(int), addPoint, removePoint, clearPoints, getNPoints

getSymbol

public GChart.Symbol getSymbol()

Returns the symbol associated with this curve.

Though you cannot set the symbol itself (there is no setSymbol method) you can have essentially the same effect by setting the SymbolType (to get qualitatively different kinds of symbols, e.g. bar-chart bars vs. boxes) and by changing symbol attributes such as background color, height, and width.

Returns:

the symbol used to represent points on this curve

See Also:

Symbol.setSymbolType, Symbol.setBackgroundColor, Symbol.setBorderWidth, Symbol.setBorderStyle, Symbol.setWidth, Symbol.setHeight, Symbol.setModelWidth, Symbol.setModelHeight

getYAxis

public com.googlecode.gchart.client.GChart.YAxisId getYAxis()

Returns the y-axis (Y_AXIS or Y2_AXIS) this curve is plotted on.

Returns:

an identifier, either Y_AXIS, or Y2_AXIS, indicating if this curve is plotted on the left (y) or right (y2) y-axis

See Also:

setYAxis, Y_AXIS, Y2_AXIS

isVisible

public boolean isVisible()

Is this curve visible on the chart and legend key, or is it hidden from view.

Returns:

true if the curve is visible, false otherwise.

See Also:

setVisible

onY2

public boolean onY2()

Convenience method equivalent to getYAxis()==Y2_AXIS.

Returns:

true if curve is on second y-axis, else false

See Also:

getYAxis

removePoint

public void removePoint(int iPoint)

Removes the point at the specified index.

Parameters:

iPoint - index of point to be removed.

See Also:

getPoint, addPoint(double,double), addPoint(int,double,double), clearPoints, getNPoints

removePoint

public void removePoint(GChart.Curve.Point p)

Removes the given point from this curve.

If the given point is not on this curve, or is null, an exception is thrown.

Parameters:

p - the point to be removed.

setHovertextTemplate

public void setHovertextTemplate(java.lang.String hovertextTemplate)

Deprecated. This method is equivalent to:

getSymbol().setHovertextTemplate(hovertextTemplate)

It is retained only for GChart 1.1 compatibility purposes.

See Also:

Symbol.setHovertextTemplate

setLegendLabel

public void setLegendLabel(java.lang.String legendHTML)

Sets the HTML that defines the label shown to the right of the icon representing the curve's symbol in the chart's legend.

Setting the legend label to null removes the entire row (the label and the icon) associated with this curve from the chart key.

Note that, since null is the default, unless you set at least one legend label, no chart key will appear at all.

Parameters:

legendHTML - the HTML defining this curve's legend label. or null to remove the curve from the legend entirely.

See Also:

getLegendLabel, setLegendThickness

setVisible

public void setVisible(boolean isVisible)

Defines if this curve is visible both in the plotting region and on the legend key.

Notes:

1. A curve must also have a non-null legend label if it is to appear on the legend key.

2. Hidden curves are excluded from the computation of any auto-computed axis limits.

Parameters:

isVisible - false to hide curve, true to reveal it.

See Also:

isVisible, setLegendLabel

setYAxis

public void setYAxis(com.googlecode.gchart.client.GChart.YAxisId axisId)

Sets the y-axis that this curve is plotted on.

Parameters:

axisId - must be either GChart.Y_AXIS or GChart.Y2_AXIS

See Also:

getYAxis, Y_AXIS, Y2_AXIS