Is there a way to get fragment from top of stack?

android, android-fragments

Solution

Some thing like this should help your activity figure this out on backpress:

private Fragment getCurrentFragment(){
    FragmentManager fragmentManager = getSupportFragmentManager();
    String fragmentTag = fragmentManager.getBackStackEntryAt(fragmentManager.getBackStackEntryCount() - 1).getName();
    Fragment currentFragment = fragmentManager.findFragmentByTag(fragmentTag);
    return currentFragment;
}

@Override
public void onBackPressed() {
    Fragment fragmentBeforeBackPress = getCurrentFragment();
    // Perform the usual back action
    super.onBackPressed();
    Fragment fragmentAfterBackPress = getCurrentFragment();
}

Hope this helps.

Problem

I have a ListFragment in my MainActivity. Here is how I set my fragment object. ``` FragmentManager fragmentManager = activity.getSupportFragmentManager(); FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); Fragment newFragment = new MyFragment(); fragmentTransaction.replace(R.id.framecontainer, newFragment, "tag"); fragmentTransaction.addToBackStack(null); fragmentTransaction.commit(); ``` The problem is when the user press back button, I have to, at least, change the action bar and menu by calling ``` getActionBar().setTitle(title); getActionBar().setDisplayHomeAsUpEnabled(isEnabled); invalidateOptionsMenu(); ``` I have to know what kind of fragment is showing currently, so that I know how to set the action bar. I store the setting option in fragment as arguments. ``` String title = fragment.getArguments().getString("KEY_TITLE"); boolean isEnabled = fragment.getArguments().getBoolean("KEY_ISENABLED"); ``` I do search the related question, and I realized I could get the fragment by calling ``` MyFragment fragment = (MyFragment) getSupportFragmentManager() .findFragmentByTag("tag"); ``` However, I have to store all the tag in a custom stack, and call pop() everytime when user pressed back button in `onBackPressed()`. So, my question is that is there a way for me to get the current visible fragment from the stack directly? Note: Please keep in mind that the fragment types are different, not just only MyFragment.

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