A boolean expression that determines whether an control can respond to
user-generated events.
By default, the Enabled property is True. The Enabled
property specifies whether the entire control is enabled or disabled. The Selectable property returns or sets a value that indicates whether the layer is selectable.
You can use the Grayscale property to show the
entire layer in gray scale ( disable state). For instance, you
can simulate a disabled layer by changing the layer's Grayscale property on
True, and setting the layer's Selectable property on False.