/// <summary>
 /// Create overlay window docking button
 /// </summary>
 /// <param name="btnDock">Button dock</param>
 /// <param name="owner">Overlay window</param>
 /// <param name="enabled">Enabled flag</param>
 public OverlayWindowDockingButton(Button btnDock, OverlayWindow owner, bool enabled)
 {
     _btnDock = btnDock;
     _owner   = owner;
     _enabled = enabled;
 }
 /// <summary>
 /// Create overlay window docking button
 /// </summary>
 /// <param name="btnDock">Button dock</param>
 /// <param name="owner">Overlay window</param>
 public OverlayWindowDockingButton(Button btnDock, OverlayWindow owner) : this(btnDock, owner, true)
 {
 }