title: WPF Tooltip binding and open programatically does not work
body: <p>I have a Custom tooltip icon which also has its content bound to Datacontext. My need was to open Tooltop on mouse hover as well as on click event. So I used following code</p>
  
  <pre><code>&lt;Image Source="/MainUI;component\Images\home\tooltip_info.png" 
         Width="24" Height="24" Stretch="Fill" HorizontalAlignment="Right" 
         Name="ImageToolTip"
         Margin="0,0,0,0" MouseUp="ImageToolTip_MouseUp" MouseLeave="ImageToolTip_MouseLeave"&gt;
      &lt;Image.ToolTip&gt;
          &lt;ToolTip BorderBrush="Transparent" Background="Transparent" HorizontalOffset="-142"&gt;
              &lt;TextBlock TextWrapping="WrapWithOverflow" 
                         Style="{StaticResource ExcalFont-MSFD300}" 
                         FontSize="14" Text="{Binding Tips}" 
                         Width="300" Padding="15,15,15,15"&gt;
                  &lt;TextBlock.Background&gt;
                      &lt;ImageBrush ImageSource="Images\home\popupbox.png" /&gt;
                  &lt;/TextBlock.Background&gt;
              &lt;/TextBlock&gt;
          &lt;/ToolTip&gt;
      &lt;/Image.ToolTip&gt;
  &lt;/Image&gt;
  </code></pre>
  
  <p>Code Behind:</p>
  
  <pre><code>private void ImageToolTip_MouseUp(object sender, MouseButtonEventArgs e)
  {
      ((ToolTip)((FrameworkElement)sender).ToolTip).IsOpen = true;
  }
  
  private void ImageToolTip_MouseLeave(object sender, MouseEventArgs e)
  {
      ((ToolTip)((FrameworkElement)sender).ToolTip).IsOpen = false;
  }
  </code></pre>
  
  <p>Now the issue is on mouse up It opens Tooltip but it does not bind the text.
  This is working fine if I am using static text instead of Binding. What am I doing wrong?</p>
  
  <p>In case I mouse hover on icon then it works fine and shows the content too. Thereafter everytime mouse click also shows the tooltip content. Not sure why mouse click do not work initially. –</p>