ios - Inject custom class into subclass inheritance tree in Objective-C -


I think of myself as an experienced objective-programmer. I approve to be a survivor, and use the facilities of language completely. It involves using runtime, only-in-time changes are different in existing frameworks, like swizzling method and dynamic subclassification, the fact that this language is so versatile that it is equivalent to another object oriented equivalent .

But recently I have been thinking about an old facility, that I still think myself needs to use from time to time, but for some time now it disliked it Has been done. This is a replacement for the old class_setSuperClass .

I often find the UIKit classes subclasses in their order to expand them or just slightly alter their behavior. An example that I recently came to was a UIScrollView subclass, which had created some conditions for pangestarrequiser I did that by classifying UIScrollView and then apply gestureRecognizer: shouldBeRequiredToFailByGestureRecognizer:.

This is to be done in this way, because you do not have permission to change the pan gesture of a scroll view to the recogniser's representative (this one throws an exception exception), and you Can not create your own custom UIScrollView panGestureRecognizer

Now all this worked great out. I changed all the uses of UIScrollView in my newly created subclass, and everything worked as expected. But what about the UITableView and UICollectionView which I have also used for the whole app, what to do with those people? As you know, both of these sections are inherited from UIScrollView , but there is no my custom sub-class for UIScrollView . That's why I ended up writing the same code several times for every class inherited from UIScrollView (and it was used in the app) . Writing the same code multiple times is not programmer 1-2-3. But I had finished writing a custom subclass for UIScrollView but instead of UITableView and UICollectionView

. With the class_setSuperClass you were able to already have a pre-package class super class UITableView like "sly" . You basically just call class_setSuperClass ([UITableView class], [MyScrollView class]), and everything went fine (ok almost) okay. Now you injected your code between UITableView and UIScrollView . So every time you did [[UITableView alloc] init] , there were attributes of MyScrollView because it was inherited directly from it.

Now was excluded from Class_setSuperClass iOS 2.0! Since we can swing and hacking some of the object's isa pointer. Now it has also been deprecated.

So my question is really simple how will you approach this?

After "text" itemprop = "text">

You want to change the behavior of a class globally to play with the class instead of identifying , The direct approach just needs to change the method you have to replace. Runtime still allows it with class_replaceMethod () . It seems that what you want is the easiest way to complete it.

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