Package org.jfree.chart.plot

Class CrosshairState

java.lang.Object
org.jfree.chart.plot.CrosshairState
public class CrosshairState
extends Object
Maintains state information about crosshairs on a plot.

  • Constructor Summary

    Constructors
    Constructor Description
    CrosshairState()
    Default constructor.
    CrosshairState​(boolean calculateDistanceInDataSpace)
    Creates a new info object.

  • Method Summary

    Modifier and Type Method Description
    double getCrosshairX()
    Get the x-value for the crosshair point.
    double getCrosshairY()
    Get the y-value for the crosshair point.
    void setAnchor​(Point2D anchor)
    Sets the anchor point.
    void setCrosshairDistance​(double distance)
    Sets the distance between the anchor point and the current crosshair point.
    void setCrosshairX​(double x)
    Sets the x coordinate for the crosshair.
    void setCrosshairY​(double y)
    Sets the y coordinate for the crosshair.
    void updateCrosshairPoint​(double x, double y, double transX, double transY, PlotOrientation orientation)
    Evaluates a data point and if it is the closest to the anchor point it becomes the new crosshair point.
    void updateCrosshairX​(double candidateX)
    Evaluates an x-value and if it is the closest to the anchor point it becomes the new crosshair point.
    void updateCrosshairY​(double candidateY)
    Evaluates a y-value and if it is the closest to the anchor point it becomes the new crosshair point.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • CrosshairState

      public CrosshairState()
      Default constructor.

    • CrosshairState

      public CrosshairState​(boolean calculateDistanceInDataSpace)
      Creates a new info object.
      Parameters:
      calculateDistanceInDataSpace - a flag that controls whether the distance is calculated in data space or Java2D space.

  • Method Details

    • setCrosshairDistance

      public void setCrosshairDistance​(double distance)
      Sets the distance between the anchor point and the current crosshair point. As each data point is processed, its distance to the anchor point is compared with this value and, if it is closer, the data point becomes the new crosshair point.
      Parameters:
      distance - the distance.

    • updateCrosshairPoint

      public void updateCrosshairPoint​(double x, double y, double transX, double transY, PlotOrientation orientation)
      Evaluates a data point and if it is the closest to the anchor point it becomes the new crosshair point.

      To understand this method, you need to know the context in which it will be called. An instance of this class is passed to an XYItemRenderer as each data point is plotted. As the point is plotted, it is passed to this method to see if it should be the new crosshair point.

      Parameters:
      x - x coordinate (measured against the domain axis).
      y - y coordinate (measured against the range axis).
      transX - x translated into Java2D space.
      transY - y translated into Java2D space.
      orientation - the plot orientation.

    • updateCrosshairX

      public void updateCrosshairX​(double candidateX)
      Evaluates an x-value and if it is the closest to the anchor point it becomes the new crosshair point.

      Used in cases where only the x-axis is numerical.

      Parameters:
      candidateX - x position of the candidate for the new crosshair point.

    • updateCrosshairY

      public void updateCrosshairY​(double candidateY)
      Evaluates a y-value and if it is the closest to the anchor point it becomes the new crosshair point.

      Used in cases where only the y-axis is numerical.

      Parameters:
      candidateY - y position of the candidate for the new crosshair point.

    • setAnchor

      public void setAnchor​(Point2D anchor)
      Sets the anchor point. This is usually the mouse click point in a chart panel, and the crosshair point will often be the data item that is closest to the anchor point.
      Parameters:
      anchor - the anchor point.

    • getCrosshairX

      public double getCrosshairX()
      Get the x-value for the crosshair point.
      Returns:
      the x position of the crosshair point.

    • setCrosshairX

      public void setCrosshairX​(double x)
      Sets the x coordinate for the crosshair. This is the coordinate in data space measured against the domain axis.
      Parameters:
      x - the coordinate.

    • getCrosshairY

      public double getCrosshairY()
      Get the y-value for the crosshair point. This is the coordinate in data space measured against the range axis.
      Returns:
      the y position of the crosshair point.

    • setCrosshairY

      public void setCrosshairY​(double y)
      Sets the y coordinate for the crosshair.
      Parameters:
      y - the y coordinate.