Inheritance seemingly not fully supported about injectioniii

[johnno1962]

Hi, you seem to have a couple of issues mixed into one. Firstly, injection only updates function implementations but the new implementations are not re-called automatically. So, it cannot arrange for your ViewController to redraw and update the display on its own; You need to use one of the techniques described in the project README. That aside, inherited methods, particularly across modules is a tricky problem and you may have run across a limitation. Remember though, when injecting an inherited method remember to inject the superclass then inject the subclass again so it gets a change to update the subclass' vtable if you want to see it work.

[chrisknapp98]

My issue is completely unrelated to calling any methods, I know that. I just wanted to make clear how this specific architecture looks like.

I only expect a ViewControllers viewDidLoad() method to be re-executed because of the extension mentioned in the README

#if DEBUG
extension UIViewController {
    @objc func injected() {
        viewDidLoad()
    }
}
#endif

However, the viewDidLoad() is not executed when using those types from another module.

Unfortunately in my context adding a library to production code is not an option, so I am only able to load InjectionIII's bundle in AppDelegate, add the extension and the linker flags to the example project.

Have you got any further suggestion or am I maybe missing something?

[johnno1962]

Let's separate this into two problems. Are you saying the injected() method you add in your example project dependant on a pod containing the ViewControllers you're using isn't called? That would be unusual. Leave the sayHi() method to one side for a second.

[chrisknapp98]

yeah exactly. I updated the code to reduce confusion. There's no issue with calling any inherited methods whatsoever.

My only problem is that I need to go back and push the ViewController again to see the changes

[johnno1962]

I can see how that might happen though I need to think about it some more. The problem won't be with the @objc injected() method but the dispatch of the viewDidLoad() through the vtable(s). Recapping, which "the" ViewController do you need to push again to see the changes? If you see the changes, how does this not meet your expectations?

[chrisknapp98]

I need to push the TestViewController again (the one I am working on).
However, if at runtime I change TestViewController the following way, then my changes within viewDidLoad() update right-away.

class TestViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .systemGreen // changes are updated automatically in Simulator
    }
}

[johnno1962]

So if TestViewController inherits UIViewController directly it works but if it inherits MyViewControllerBase it doesn't?

[chrisknapp98]

exactly!

[chrisknapp98]

Unfortunately I cannot share the code with you. But maybe I find some time in the coming days to reproduce this in a sample project set up with cocoapods.
But I think now you're understanding my problem.

[johnno1962]

Very strange, I may take a look tomorrow if I can think of something fixable. It would be very helpful to me if you were able to prepare a small project demoing the problem.

[chrisknapp98]

Sure, but give me some days! You can also wait to not waste your time in case my problem lays somewhere else and I don't manage to reproduce it

[johnno1962]

Thanks! That would be very helpful; no hurry. By the way, I don't have Cocoapods installed on my machine but you should be able to replicate your problem by putting your superclasses in a framework target which is what Cocoapods does anyway.

[johnno1962]

Just a thought. Have you tried adding the injected() method to your TestViewController?

    @objc func injected() {
        viewDidLoad()
    }

[johnno1962]

Hi, I've tried a few things with a test project and not been able to replicate this problem. If you get a change to produce a small example app that shows the problem but doesn't use Cocoapods and post it here or email it to me via github at johnholdsworth.com I can take a look at it for you.

[chrisknapp98]

Just a thought. Have you tried adding the injected() method to your TestViewController?

    @objc func injected() {
        viewDidLoad()
    }

Yeah I tried that and it made no difference. It recognizes that I'd need to override it and when changing the extension from UIViewController to be on TestViewController instead, it still doesn't execute the viewDidLoad()

[chrisknapp98]

Hi, I've tried a few things with a test project and not been able to replicate this problem. If you get a change to produce a small example app that shows the problem but doesn't use Cocoapods and post it here or email it to me via github at johnholdsworth.com I can take a look at it for you.

Just spent some hours vaguely recreating the setup first with just two modules and that worked as you have stated already.
Then I tried to setup a comparable cocoapods environment and that also works fine. So the issue might be something different and I'll see if I casually find out what is causing it in the coming weeks.

So I guess we can close this issue for now and we'll see if I come back with a solution.

Thank you very much for your assistance!