title: Update mediaElement based on slider value
body: <p>I have a <code>mediaElement</code> and a <code>slider</code>.<br/>
  The slider's maximum value is video's duration in seconds (for example if the video is 2 minutes, the slider's value is 120).</p>
  
  <p>I want to update the mediaElement.Position based on the slider's value but the problems is that I dont want to update the position until the user FINISHED manipulating the value.</p>
  
  <p>so what I did is 2 functions:</p>
  
  <pre><code>private void DurationSlider_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e)
  {
      SeekToMediaPosition();
  }
  </code></pre>
  
  <p>this function applys if the user stopped manipulating the slider.</p>
  
  <pre><code>private void DurationSlider_ValueChanged(object sender, RangeBaseValueChangedEventArgs e)
  {
       SeekToMediaPosition();
  }
  </code></pre>
  
  <p>this function applys if the user clicked on different value in the slider.</p>
  
  <p>The problem is that they clash.<br/>
  Manipulating the slider cause the value to be changed...</p>
  
  <p>so What I did is added this function:</p>
  
  <pre><code>bool manipulating = false;
  private void DurationSlider_ManipulationStarted(object sender, ManipulationStartedRoutedEventArgs e)
  {
      manipulating = true;
  }
  </code></pre>
  
  <p>and in the ValueChanged function I checked whether <code>manipulating = true</code> or not <br/>
  It solved half of the problem - it does not change the video position while manipulating (until I finish) but if I click on different position on the slider (without releasing the mouse) and continue manipulating the slider's value - it changes the video position to where I clicked on the slider and then changes again to where I ended the manipulation.</p>
  
  <p>So whats wrong?<br/>
  I want to change the video position <strong>ONLY</strong> when the user released the mouse.
  I cant find event that fires what I want...</p>