Just a quick note today. I’ve previously written here (and also here: whoops!) about my UIButton+NavButton category, which I use to create my own “back” buttons for navigation controllers, so that I can cross-fade them properly.
It turns out that the code (header here, implementation here) works just fine on high-resolution devices. The only thing you need do to completely support such devices is to provide some high-resolution artwork. Just grab the high-def back_norm@2x.png and back_click@2x.png images and include them in your project; the runtime will detect and use them automatically when appropriate. (Leave the original artwork in place for standard resolution screens.)
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