private void CheckBox_Click(object sender, RoutedEventArgs e) { if ((sender as CheckBox).IsChecked == true) { IViewModel viewModel = DataContext as IViewModel; if (viewModel != null) { viewModel.CheckPermission((grdPermissions.SelectedItem as PermissionItemClass).Identifier); } ; } else { IViewModel viewModel = DataContext as IViewModel; if (viewModel != null) { viewModel.UnCheckPermission((grdPermissions.SelectedItem as PermissionItemClass).Identifier); } ; } }