Why are my UISegmentControl segments highlighting in iOS 8 when I have set background images for all states?

Question

In iOS 6/7, I have used UISegmentedControl with background images to create an effect like so:

Answer 1

The reason the segment turns grey on selecting an already selected segment is because the segmented control is missing the state for selected and highlighted at the same time.

In your case calling:

[self.segmentedControl setBackgroundImage:segmentedControlBackgroundSelectedImage forState:UIControlStateSelected | UIControlStateHighlighted barMetrics:UIBarMetricsDefault];

should fix that problem.

when you change your selection, the cell you tapped turns gray until the transition completes

I couldn't reproduce that one, but perhaps this will fix both issues.

Answer 2

Just in case, in Swift that would be (UPD for Swift 4)

segmentedControl.setBackgroundImage(image, forState: .selected, barMetrics:.Default)

segmentedControl.setBackgroundImage(image, forState: .highlighted, barMetrics:.Default)