title: Imageview in framelayout not visible
body: <p>Hi I am developing an android video app. I have a button in frame layout as in below code</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="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical" &gt;
  
  &lt;FrameLayout
      android:id="@+id/videoview"
      android:layout_width="match_parent"
      android:layout_height="match_parent" &gt;
  
      &lt;Button
          android:id="@+id/camerabutton"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_gravity="right"
          android:drawableTop="@drawable/videocamera"
          android:text="REC"
          android:textSize="12dp" /&gt;
  &lt;/FrameLayout&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>This is how, I am using the <code>FrameLayout onCreate</code></p>
  
  <pre><code>    myCamera = getCameraInstance();
      myCameraSurfaceView = new MyCameraSurfaceView(this, myCamera);
      final FrameLayout myCameraPreview = (FrameLayout)findViewById(R.id.videoview);
      myCameraPreview.addView(myCameraSurfaceView);
  </code></pre>
  
  <p>where getCameraInstance is as below </p>
  
  <pre><code>private Camera getCameraInstance()
  {
      try 
      {
          c = Camera.open(); // attempt to get a Camera instance
      }
  
      catch (Exception e)
      {
          // Camera is not available (in use or does not exist)
      }
      return c; // returns null if camera is unavailable
  }
  </code></pre>
  
  <p>and the <code>MyCameraSurfaceView</code> is as below-</p>
  
  <pre><code>public class MyCameraSurfaceView extends SurfaceView 
                                      implements SurfaceHolder.Callback{
  
      private SurfaceHolder mHolder;
      private Camera mCamera;
  
      public MyCameraSurfaceView(Context context, Camera camera)
      {
          super(context);
          mCamera = camera;
  
          mHolder = getHolder();
          mHolder.addCallback(this);
          // deprecated setting, but required on Android versions prior to 3.0
          mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
      }
  
      @Override
      public void surfaceChanged(SurfaceHolder holder, int format, int weight,
              int height)
      {
          if (mHolder.getSurface() == null)
          {
              // preview surface does not exist
              return;
          }
  
          try 
          {
              mCamera.stopPreview();
          } 
          catch (Exception e)
          {
  
          }
  
          // start preview with new settings
          try 
          {
              mCamera.setPreviewDisplay(mHolder);
              mCamera.startPreview();
  
          } 
          catch (Exception e)
          {
          }
      }
  </code></pre>
  
  <p>The button in the frame layout is <code>not visible</code>. I have very less knowledge on frame layout. I am not sure how to make the button visible. <br/>Please 
   help. Thanks! </p>