/// <summary>
/// Event handler for the <see cref="PreviewMouseLeftButtonDown"/> event
/// </summary>
/// <remarks>
/// Occurs when the left mouse button is pressed while the mouse pointer is over this element.
/// </remarks>
/// <param name="sender">the sender of the event</param>
/// <param name="e">the <see cref="MouseButtonEventArgs"/> associated to the event</param>
private void PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
if (e.ClickCount != 1 || VisualTreeExtensions.HitTestScrollBar(sender, e) ||
VisualTreeExtensions.HitTestGridColumnHeader(sender, e))
{
this.dragInfo = null;
return;
}
this.dragInfo = new DragInfo(sender, e);
}