public void addViewPortListener(ViewPortListener listener)

Adds the specified ViewPortListener to receive viewport events.

Currently, viewport events include the "viewport changed" event and the "selection changed" event. The "viewport changed" event occurs when the viewport is changed by mouse actions (see ChartViewer.setMouseUsage), or ChartViewer.updateViewPort is called. The "selection changed" event occurs when the selection box is changed (becomes visible or invisible or change in size) by "drag to select" mouse actions.

None