Why CleanActivity.java needs to implement BaseView.java interface?

[TonyTangAndroid]

Hi Jordi, it's me again. I have been pushing myself working my project to clean architecture and things become clearer and clearer. But there are still mysteries that I am wondering. For example,

Why CleanActivity.java needs to implement BaseView.java interface?

If I remove the interface implementation and the override annotation, everything will still works okay. I get a feeling that there must be a reason that rationales you making this decision. But I fail in figuring it out. Could you kindly please elaborate it for me?

I have created a pull request to my own forked project just to demonstrate the difference with our without the interface implementation. You could refer the pull request here:

https://github.com/TonyTangAndroid/android-base/pull/4/files

[jordifierro]

Hi @TonyTangAndroid!

The idea of making CleanActivity implement BaseView is to allow BaseFragment (which also implements it) to delegate some methods to its parent activity. But there is an error: instead of casting the activity to BaseView, the cast is done to CleanActivity, losing the benefits of the interface...

@Override
public void close() {
    ((CleanActivity)getActivity()).close();
}

must be replaced with:

@Override
public void close() {
    ((BaseView)getActivity()).close();
}

as well as all the BaseView methods called on CleanActivity.

[TonyTangAndroid]

I see. No wonder. It makes sense. Thank you again.