How to check at runtime if a class method exists or not?

Question

Since iOS5, UIKit can be customized with custom images. We have an app which must stay compatible with iOS 4, but if a user has iOS 5 we want to customize a slider.

Example:

[[UISlider appearance] setMaximumTrackImage:maxImage forState:UIControlStateNormal];

What's a safe way for checking at runtime if it's OK to do this call? The respondsToSelector: method is for instances only, but here it's a class itself.

Check this out: http://stackoverflow.com/questions/1135366/class-method-equivalent-of-respondstoselector — Stavash, Feb 10 '12 at 19:42

score 8 · Accepted Answer · answered Feb 10 '12 at 19:47

8

You can use resolveClassMethod: for that, e.g.:

[MYClass resolveClassMethod: @selector(trololo)];

Or you can use respondsToSelector: since classes are also objects in Objective C.

answered Feb 10 '12 at 19:47

Max

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"trololo", indeed, as the default implementation of `resolveClassMethod:` returns `NO`. – NeoNacho Jan 16 '13 at 12:25

How to check at runtime if a class method exists or not?

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