Fragment declared target fragment that does not belong to this FragmentManager

问题

I have made an activity A which has a fragment X in it. In fragment X, EditText item has on click event which opens fragment Y. This fragment displays a list of names. I press a name in the list, fragment Y closes and sends the selected name of to fragment X EditText. Here's the code I wrote:

YFragment y = new YFragment();
y.setTargetFragment(x.class, code);
getActivity().getSupportFragmentManager()
    .beginTransaction()
    .replace(R.id.frame, y)
    .addToBackStack(null)
    .commit();

In fragment Y I have the code to send the data but the problem is in this block of code above. If I comment out the setTargetFragment line the code will work but no use as data will not be sent. If I run the app this error occurs:

java.lang.IllegalStateException: Fragment y{46d3d31 #3 id=0x7f090069} declared target fragment x{e2c16 #0 id=0x7f090104 android:switcher:2131296516:0} that does not belong to this FragmentManager!

回答1:

To use setTargetFragment(), both the new Fragment and the target Fragment must be hosted within the same FragmentManager. The most common case where this would not happen is if you are using Activity.getSupportFragmentManager() or Fragment.getFragmentManager() alongside Fragment.getChildFragmentManager().

回答2:

In my solution, replace

getChildFragmentManager()

with

Activity.getSupportFragmentManager() or Fragment.getFragmentManager()

that worked for me. Thank Mr.Ben P

来源：https://stackoverflow.com/questions/47045788/fragment-declared-target-fragment-that-does-not-belong-to-this-fragmentmanager