macOS Make Window background semi transparent

[SRossi]

Hi all again, I'm trying to change the transparency of the background of a Window. This will be done on a click of a button which is placed on the window.

Heres my code so far:

- (IBAction)changeOpacity:(id)sender
{
	NSWindow *aWindow;
	
	[aWindow setOpaque:NO];
	NSColor *semiTransparentBlue = [NSColor colorWithDeviceRed:0.0 green:0.0 blue:1.0 alpha:0.5];
	[aWindow setBackgroundColor:semiTransparentBlue];
}

PS I dont know how to set the current window to aWindow help with that would be good as well

Thanks all in advance

Stephen

 

[SRossi]

Got it working my mistake, but can i ask how would I make the background change when the user moves a slider ?

Can I bind the value of the slider to the background of the window?

Stephen

 

[kainjow]

You can observe for changes to that value in your controller, and then set the background color. See addObserver:forKeyPathptions:context:

 

[SRossi]

Right I created a binding in IB from a slider to a float i created but when i move the slider it creates all kind of funny numbers.

Should I create the binding programatically as kainjow says, if so is there any sample code that I could use?

Thanks.

Stephen