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Android

Ryan Huai
Ryan Huai
6,665 Points
Posted by Ryan Huai
Ryan Huai
6,665 Points

fragment not from support library still works properly. Why?

According to the video, in order to make the back button works properly, activity and fragment should be either both from appcomat library or both from support library. But the fragment in my code does not use support library and back button still works. Can somebody explain why?

follows are the code from MainActivity: package teamtreehouse.com.smellslikebakin;

import android.app.Fragment; import android.app.FragmentManager; import android.app.FragmentTransaction; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements ListFragment.OnRecipeSelectedInterface{

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //when app is rotated, the fragment will be automatically created, hence, no need to create again.
    ListFragment savedFragment = (ListFragment) getFragmentManager().findFragmentById(R.id.placeHolder);
    if (savedFragment == null ) {
        ListFragment fragment = new ListFragment();
        FragmentManager fragmentManager = getFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.add(R.id.placeHolder, fragment);
        fragmentTransaction.commit();
    }
}