WPF, multi-linking CSV with checkbox list and MVVM best practices

Question

I am relatively new to the whole concept of WPF and MVVM, and I am looking for best practice tips. I have a solution that works, but it looks like I can skip some great XAML syntax that will simplify all this.

I have a string field in a database table that is stored as a CSV, for example. "COTOPES". Perhaps I should have done this as a many-to-many relationship in my entity data model, but this is a great discussion on best practice.

In my XAML, I use multibinding in a ListBox that contains CheckBoxes. The scope of options is determined at runtime, and the ListBox generates CheckBoxes using the DataTemplate. Here's the XAML:

    <ListBox Grid.Column="3" Grid.Row="8" Grid.RowSpan="2" Name="brandedProductsListBox" Margin="3" ItemsSource="{Binding Source={StaticResource brandedProductLookup}}" IsSynchronizedWithCurrentItem="True" TabIndex="475">
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <CheckBox Margin="3" Content="{Binding Path=BrandedProductName}" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked">
                <CheckBox.IsChecked>
                    <MultiBinding Converter="{StaticResource brandedProductToBoolean}">
                        <Binding Source="{StaticResource projectsView}" Path="BrandedProducts" />
                        <Binding Path="BrandedProductName" />
                    </MultiBinding>
                </CheckBox.IsChecked>
            </CheckBox>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ListBox>

CheckBoxes. ConvertBack- CSV, , , BrandedProductName, , , . :

public class BrandedProductToBooleanConverter : IMultiValueConverter
{
    public object Convert(object[] value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value == null) {
            return false;
        }
        else {
            // The bindings passed in (in order) are: the BrandedProducts field for the current project, 
            // and the Branded Product represented by the current CheckBox.
            string brandedProducts = value[0] as string;
            string brandedProduct = value[1] as string;
            return brandedProducts == null ? false :  brandedProducts.Contains(brandedProduct);
        }
    }

    public object[] ConvertBack(object value, Type[] targetType, object parameter, CultureInfo culture)
    {
        return null;
    }
}

So Convert CheckBoxes, , , , Checked UnChecked CheckBox , :

        private void CheckBox_Checked(object sender, RoutedEventArgs e)
    {
        if (projectView.IsAddingNew) {
            CheckBox checkBox = sender as CheckBox;
            NewProject project = projectView.CurrentAddItem as NewProject;
            if (project.BrandedProducts == null) {
                project.BrandedProducts = (string)checkBox.Content;
            }
            else {
                project.BrandedProducts += ", " + (string)checkBox.Content;
            }
        }
        e.Handled = true;
    }

    private void CheckBox_Unchecked(object sender, RoutedEventArgs e)
    {
        if (projectView.IsAddingNew) {
            CheckBox checkBox = sender as CheckBox;
            NewProject project = projectView.CurrentAddItem as NewProject;
            if (project.BrandedProducts != null) {
                project.BrandedProducts = project.BrandedProducts.Replace((string)checkBox.Content + ", ", "").Replace(", " + (string)checkBox.Content, "");
            }
        }
        e.Handled = true;
    }

, , ? , , / . - MVVM ViewModel ?

, Ray

Answer 1

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, WPF, , , . ( wimpy WinForms).

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, , MVVM. ViewModel ( ViewModel) .

, ICommand (), ViewModel (.. Add, Remove). . EventToCommand, , , CheckBox_Checked CheckBox_UnChecked.

-jberger