title: android RelativeLayout for all devices
body: <p>I am trying use relative layout for some android application.</p>
  
  <pre><code>&lt;Button
          android:layout_width="100dip"
          android:background="#ff394aff"
          android:text="start"
          android:layout_height="wrap_content"
  
          android:layout_marginLeft="225dp"
          android:layout_marginTop="225dp"
  
          android:id="@+id/start" android:layout_gravity="center_horizontal" android:layout_weight="0.50"/&gt;
  </code></pre>
  
  <p>but the in some devices will appear in a different positons. I tried "dip" and "sp" but the problem remains.
  help me how to do it so that in all devices the positions be same?</p>