PaletteViewer.addPaletteListener(
PaletteListener paletteListener)
Adds the given PaletteListener as the one to be notified when the active tool on the
palette changes.
void
PaletteViewer.removePaletteListener(
PaletteListener paletteListener)
The given PaletteListener will not be notified of active tool changes in the palette.