Returns the amount of alpha in the color, from 0 (transparent) to 255 (opaque).
@return the alpha component of the color
@exception SWTException <ul> <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> </ul> @since 3.104
See Implementation
Returns the amount of alpha in the color, from 0 (transparent) to 255 (opaque).
@return the alpha component of the color
@exception SWTException <ul> <li>ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed</li> </ul> @since 3.104