title: Android programming setContentView does not show xml layout
body: <p>In onCreate method I have this code:</p>
  
  <pre><code>@Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      requestWindowFeature(Window.FEATURE_NO_TITLE);
      setContentView(R.layout.activity_main_sin_login);
      .....
  </code></pre>
  
  <p>Here is my activity_main_sin_login</p>
  
  <pre><code>&lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:gravity="center"
      android:paddingBottom="@dimen/activity_vertical_margin"
      android:paddingLeft="@dimen/activity_horizontal_margin"
      android:paddingRight="@dimen/activity_horizontal_margin"
      android:paddingTop="@dimen/activity_vertical_margin" 
      android:background="@drawable/estilofondobarraprincipal"&gt;
  
      &lt;ImageView
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:background="@drawable/carga_inicial" /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>Why my app does not show this layout when the activity starts? I have used clean eclipse option but it does not work. My application only shows a blank page</p>
  
  <p>Thanks and best regards.</p>