Returns the receiver’s current alpha value based on its opacity slider.
Original signature is '- (CGFloat)alpha'
Available in Mac OS X v10.0 and later.
Assembly: Monobjc.AppKit (Module: Monobjc.AppKit)
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)