Fragment isAdded() returns false on an already added Fragment

android fragment fragmenttransaction
Lumbi picture Lumbi · Mar 18, 2014 · Viewed 20.2k times · Source

I have this neat function:

private void addMapFragment(){
    if(!mapFragment.isAdded()){
        FragmentTransaction ft = getFragmentManager().beginTransaction();
        ft.add(R.id.mapContainer, mapFragment);
        ft.commit();
    }
}

I'm calling addMapFragment() in my activity's onCreate(). I then have a callback from a webrequest that calls addMapMapFragment(). The isAdded() method doesn't look useful at all since I'm getting a crash saying "Fragment already added: MapFragment[...]"

Any clue?

Answer

Philipp Jahoda picture Philipp Jahoda · Mar 18, 2014

FragmentTransactions are committed asynchronously. Therefore, you need to call

getFragmentManager().executePendingTransactions();

before you call 

Fragment.isAdded();

That way, you can make sure that everything is up to date.

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