SettingsActivity.java

package de.devland.masterpassword.ui.preferences;

import android.app.FragmentManager;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;

import de.devland.masterpassword.R;

public class SettingsActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_settings);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        if (savedInstanceState == null) {
            getFragmentManager().beginTransaction()
                    .add(R.id.container, new SettingsFragment())
                    .commit();
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == android.R.id.home) {
            FragmentManager fm = getFragmentManager();
            if (fm.getBackStackEntryCount() > 0) {
                fm.popBackStack();
            } else {
                NavUtils.navigateUpFromSameTask(this);
            }
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onBackPressed() {
        FragmentManager fm = getFragmentManager();
        if (fm.getBackStackEntryCount() > 0) {
            fm.popBackStack();
        } else {
            super.onBackPressed();
        }
    }
}