How to set selected image of UIButton in XCode Interface Builder

I have two image sets for "flag" button in my Images.xcassets: flag-highlighted and flag-normal, where each set has 3 images of size x1, x2, x3

I use the flag-normal image set for the Image attribute in the attributes inspector for this button. But, where/how do I specify the flag-highlighted image set for the selected state?

Solution

You can set image for specific button state via interface builder by using state config option.

Choose selected option and then pick your image for selected state.