Actionbar's overflow menu open/close listener

问题

I want to listen when user opens/closes the overflow menu (three dots) of ActionBar, someway like this:

void onOverflowMenu(boolean expanded) {
}

To handle open cases, I've tried onPrepareOptionsMenu(), but it's triggered when ActionBar is constructed or when invalidateOptionsMenu() is called. This is not what I want.

I was able to detect overflow menu is closed if user selects a menu item in onMenuItemSelected(). But I also want to detect it if user closes overflow menu by tapping outside of it, by pressing back key, and all other cases.

Is there a way to implement that?

回答1:

To catch open action in the Activity:

@Override
public boolean onMenuOpened(int featureId, Menu menu) {
    ...
    return super.onMenuOpened(featureId, menu);
}

To catch closed action, also if user touch outside of Menu view:

@Override
public void onPanelClosed(int featureId, Menu menu) {
    ...
}

回答2:

IMHO the simplest way is to set ActionBar.OnMenuVisibilityListener

ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
    actionBar.addOnMenuVisibilityListener(new ActionBar.OnMenuVisibilityListener() {
        @Override
        public void onMenuVisibilityChanged(boolean isVisible) {
            if (isVisible) {
                // menu expanded
            } else {
                // menu collapsed
            }
        }
    });
}

来源：https://stackoverflow.com/questions/23806383/actionbars-overflow-menu-open-close-listener