Enable ActionBar app icon to behave as action to go back

AndroidManifest.xml

@@ -15,14 +15,17 @@
         android:theme="@style/AppTheme" >
         <activity
             android:name="i2p.bote.MailListActivity"
-            android:label="@string/app_name" >
+            android:label="@string/app_name"
+            android:launchMode="singleTop" >
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
-        <activity android:name="i2p.bote.ViewEmailActivity" />
+        <activity
+            android:name="i2p.bote.ViewEmailActivity"
+            android:parentActivityName="i2p.bote.MailListActivity" />
     </application>
 
 </manifest>

src/i2p/bote/ViewEmailActivity.java

@@ -38,6 +38,9 @@ public class ViewEmailActivity extends ActionBarActivity implements
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_view_email);
 
+        // Enable ActionBar app icon to behave as action to go back
+        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
+
         Intent i = getIntent();
         String folderName = i.getStringExtra(FOLDER_NAME);
         mFolder = BoteHelper.getMailFolder(