Activity with DrawerLayout not added to back stack

Question

I have an application using the android DrawerLayout and the NavigationView to provide a drawer.

The drawer works great, and the menu items are active. When I click on a menu item that launches a new activity, the activity renders, and the toolbar shows a backarrow.

However, when I click the back arrow from the new activity, I do not return to the original activity with the DrawerLayout. Instead, I am backed out of the application altogether!

I had thought that if I specified a parent activity in the AndroidManifest.xml that the back arrow would lead to the parent; but this does not appear to be the case.

What do I need to do in the new activity (or in the original activity) to ensure that the back function works properly ?

manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.x.y" >

    <uses-permission android:name="android.permission.SET_DEBUG_APP" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".Home"
            android:exported="true"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".ui.settings.FilterPreferences"
            android:label="@string/title_activity_filter_preferences"
            android:parentActivityName=".Home">
        </activity>
    </application>

</manifest>

Drawer Activity Home.java

New Activity FilterPreferences.java

public class FilterPreferences extends AppCompatActivity {

    private Toolbar mToolbar;

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

        // Initialize the toolbar
        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(mToolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setDisplayShowHomeEnabled(true);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_filter_preferences, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

Answer 1

The issue was that the calling activity was killing itself after launching the new activity.

   private void displaySettingsPage() {
        Intent i = new Intent(Home.this, FilterPreferences.class);
        startActivity(i);
        finish();
    }

I would expect that the call to the back button would launch the Home activity again from onCreate(). This does not seem to occur - the parent activity must still be available to be referenced from the backstack.

The solution is to allow the system to handle the originating activity's lifecycle - the calling method then becomes:

   private void displaySettingsPage() {
        Intent i = new Intent(Home.this, FilterPreferences.class);
        startActivity(i);
    }