private void OpenPrintLevelWizard() { if (printLevelWizardWindow == null) { printLevelWizardWindow = new PrintLevelWizardWindow(); printLevelWizardWindow.Closed += (sender, e) => { printLevelWizardWindow = null; }; printLevelWizardWindow.ShowAsSystemWindow(); } else { printLevelWizardWindow.BringToFront(); } }