Overlay

All Known Implementing Classes:

CrosshairOverlay
```
public interface Overlay
```
Defines the interface for an overlay that can be added to a ChartPanel.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	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.