Comment by sandoze

In Objective-C we can create methods, properties and classes on the fly using <objc/runtime.h>

Here's how to create a property on the fly (great for categories)

@dynamic progressView;

- (void)setProgressView:(ACProgressView )progressView { objc_setAssociatedObject(self, ACProgressViewKey, progressView, OBJC_ASSOCIATION_RETAIN_NONATOMIC); }

- (ACProgressView )progressView { return objc_getAssociatedObject(self, ACProgressViewKey); }