使用backstack时android.app.Fragment和android.support.v4.app.Fragment的不同行为

Question

I've created Activity and added a fragment to it using FragmentManeger . When i use android.app.Fragment and press the back button my application closes. When i use android.support.v4.app.Fragment and press the back button, the fragment is removed from the activity, but application is still working. I can't really understand why is that happening.

Here is the code i used:

Activity:

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

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

        getFragmentManager().beginTransaction()
            .replace(R.id.content_fragment, new Fragment1())
            .addToBackStack("first")
            .commit();
    }
}

Fragment:

import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class Fragment1 extends Fragment {

    public Fragment1() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
         // Inflate the layout for this fragment
         return inflater.inflate(R.layout.fragment_fragment1, container, false);
    }
}

When i simply replace import in Activity and Fragment to same classes, but in the support library, the result is different...

EDIT: I also replaced getFragemetManeger() to getSupportFragmentMeneger() and it still works different

Answer 1

if you're only looking to change the back behavior, you can try overriding onBackPressed with something like:

if(backstackCount() > 0)
{
     super.onBackPressed
}

Answer 2

The issue occured because i used android.support.v7.app.AppCompatActivity and android.app.Fragment. I should've used android.app.Fragment with android.app.Activity or AppCompatActivity with support fragment.