title: How do I force showing a tooltip in WPF
body: <p>I'd like to show a tooltip when I move the mouse.
  Here is my code:</p>
  
  <pre><code> private void Grid_MouseMove(object sender, MouseEventArgs e)
          {
              Grid grid = (Grid) sender;
              if (e.GetPosition(grid).X &lt; 100)
                  grid.ToolTip = e.GetPosition(grid).X.ToString();
              else
                  grid.ToolTip = null;
          }
  </code></pre>
  
  <p>However, the tooltip disappears after I click on the grid.</p>
  
  <p>Is there a way to force showing the tooltip?</p>