OwnerDrawAlpha
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Use OwnerDraw with transparency to get MediaPlayer-like effects.

The OwnerDrawCell event allows you to customize the way each 
cell is rendered. You can modify some elements of the cell or
override the painting completely.

In this example, OwnerDraw mode is used to display alpha-blended progress
bars on cells to implement a user interface similar to that of Windows
Media Player.
