private DisplayMarkerViewModel(int displayIndex) { var screen = NotificationUtil.GetScreenOfIndex(displayIndex); if (screen == null) { return; } var warea = screen.WorkingArea; if (warea.Width < 1 || warea.Height < 1) { return; } this._left = (int)((warea.Width - 300) / 2 + warea.Left); this._top = (int)((warea.Height - 60) / 2 + warea.Top); }