org.jfree.chart.panel

## Interface Overlay

-     public interface Overlay

  Defines the interface for an overlay that can be added to a `ChartPanel`.
  Since:
    1.0.13

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `addChangeListener(OverlayChangeListener listener)` Registers a change listener with the overlay.
    `void` | `paintOverlay(java.awt.Graphics2D g2, ChartPanel chartPanel)` Paints the crosshairs in the layer.
    `void` | `removeChangeListener(OverlayChangeListener listener)` Deregisters a listener from the overlay.

- - ### Method Detail

    - #### paintOverlay

          void paintOverlay(java.awt.Graphics2D g2,
                            ChartPanel chartPanel)

      Paints the crosshairs in the layer.
      Parameters:
        `g2` - the graphics target.
        `chartPanel` - the chart panel.

    - #### addChangeListener

          void addChangeListener(OverlayChangeListener listener)

      Registers a change listener with the overlay.
      Parameters:
        `listener` - the listener.

    - #### removeChangeListener

          void removeChangeListener(OverlayChangeListener listener)

      Deregisters a listener from the overlay.
      Parameters:
        `listener` - the listener.