title: setText is not working after called
body: <p>I tried everything on stackoverflow, but still can't find a solution. 
  I tried to debug by setting breakpoint, the scoreView variable's mText is being updated, it keep showing the default string <code>startingScore</code>, but the UI is not updated, i tried to call the setText using <code>onUiThread</code> function as well. 
  I can't really figure it out. Can someone help?
  Thank you so much
  (This is an augmented reality game using metaio)</p>
  
  <p>I have also checked the id of the view and string are unique. </p>
  
  <p>ARActivity.java   </p>
  
  <pre><code>public class ARActivity extends ARViewActivity {
  
      // TextView of the score, will be updated regularly
      TextView scoreView;
      ...
  
  
  //onCreate Method in ARActivity.java
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.ar_view);
      scoreView = (TextView) findViewById(R.id.arScoreView);
      scoreView.setText("Happy day");
  }
  
  // onDrawFrame method in ARActivity.java
  @Override
  public void onDrawFrame() {
      metaioSDK.render();
      scoreView.setText("Happy day");
  }
  </code></pre>
  
  <p>ar_view.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical" &gt;
  
  &lt;TextView
      android:id="@+id/arScoreView"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_alignParentLeft="true"
      android:layout_alignParentStart="true"
      android:layout_alignParentTop="true"
      android:layout_marginLeft="22dp"
      android:layout_marginStart="28dp"
      android:layout_marginTop="18dp"
      android:text="@string/startingScore"
      android:visibility="visible" /&gt;
  </code></pre>
  
  <p></p>
  
  <p>Strings.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;resources&gt;
  
  &lt;string name="app_name"&gt;Shiny Pandas&lt;/string&gt;
  &lt;string name="hello_world"&gt;Hello world!&lt;/string&gt;
  &lt;string name="action_settings"&gt;Settings&lt;/string&gt;
  &lt;string name="how_to_play"&gt;How To Play&lt;/string&gt;
  &lt;string name="new_game"&gt;New Game&lt;/string&gt;
  &lt;string name="title_activity_main_menu"&gt;Shiny Pandas&lt;/string&gt;
  &lt;string name="about_us"&gt;About Us&lt;/string&gt;
  &lt;string name="title_activity_how_to"&gt;HowToActivity&lt;/string&gt;
  &lt;string name="title_section1"&gt;Section 1&lt;/string&gt;
  &lt;string name="title_section2"&gt;Section 2&lt;/string&gt;
  &lt;string name="title_section3"&gt;Section 3&lt;/string&gt;
  &lt;string name="title_activity_about_us"&gt;AboutUsActivity&lt;/string&gt;
  &lt;string name="pause"&gt;Pause&lt;/string&gt;
  &lt;string name="startingScore"&gt;Score: 0&lt;/string&gt;
  
  &lt;/resources&gt;
  </code></pre>
  
  <p>============ UPDATE =============</p>
  
  <p>I Just realize when I click the back button on my phone back to the menu, the default text changed at that time. </p>