如何从活动中的片段管理onclicklistener？

Question

I have a question I hope someone can solve it.

I have 4 fragments for 1 activity, but just 2 of them are displayed, so I have buttons to navigate between these fragments.

All clicks must be executed in the activity, so this knows which fragment ahs to replace, so all "OnClickListener" must to implement the "OnclickListener" of the activity.

How can I solve this? Thank you!

Answer 1

There is a standard solution for this:

Define an interface, say ClickCallbacks:

interface ClickCallbacks {
    void onClick(stuff... );
}

In each fragment, implement onAttach, like this:

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    try { clickListener = (ClickCallbacks) activity; }
    catch (ClassCastException e) {
        throw new ClassCastException(
            activity.toString() + " must implement ClickCallbacks");
    }
}

Finally, implement the interface in your Activity.

This is described in pretty clear detail in the Fragment documentation here: Fragments