Question

I added a bottom bar on NSWindow in IB by select “Content Border-Large Bottom Border”. And I add a custom Image button on the bottom bar, but when I press the button, the background of the button turns into white, why?

This is the effect when press down the button:

Answer 1

Change button’s type to Momentary Change. You can change it in Attributes inspector:

Or change programatically:

[button setButtonType:NSMomentaryChangeButton];