bounding tab control items to a PROPERTY of an ObservableCollection, with a twist

Question

I have a TabControl

I followed the answer chosen here to the letter. The thing is that in my case the ExistingTabs is not an ObservableCollection, but the property of an ObservableCollection:

Public Class TestData : INotifyPropertyChanged // and the required event handler is there also, not shown here
{
    public TabItem tiTestTab {get; set;}
    // another dozen properties
}

and

public class ReportData
{
    public static ObservableCollection<TestData> testData {get;set;}
    // another dozen properties
}

Here's what I did:

<Window.Resources>
   <CollectionViewSource x:Key="ExistingTabs" Source="{Binding Path=(local:ReportDataSet.testData), Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
</Window.Resources>
<TabControl>
    <TabControl.ItemsSource>
        <CompositeCollection>
             <TabItem>SomeSpecialItem</TabItem>
             <CollectionContainer Collection="{Binding Source={StaticResource ExistingTabs}}"/>
         </CompositeCollection>
    </TabControl.ItemsSource>
</TabControl>

This, of course, places the testData in the tabs and not the tiTestTab property.

I am at a loss.

Preferably, XAML-only. Using C# and Visual Studio 2013.

Thanks.

Do you want TwoWay binding for collection, or it's enough OneWay binding? — keymusicman, Sep 06 '15 at 08:56
@VMaleev: oneway is enough. The tab control has no "delete" functionality, and all the changes occur from the observablecollection to the UI. — Gabe, Sep 06 '15 at 09:22
And there's typo i think: public class ReportData should be public class ReportDataSet? — keymusicman, Sep 06 '15 at 09:27
Static: yup. Sorry. Concerning ReportData - nope. it's a single object that holds a lot of information, ONE of which is the testData. — Gabe, Sep 06 '15 at 09:31
Actually, I've implemented PropertyChanged and PropertyChangedEventHandler for TestData.... — Gabe, Sep 06 '15 at 09:36

score 1 · Accepted Answer · answered Sep 06 '15 at 09:56

Xaml code:

<Window.Resources>
    <local:CollectionConverter x:Key="collectionConverter" />
    <CollectionViewSource x:Key="ExistingTabs" Source="{Binding Path=(local:ReportDataSet.testData), Converter={StaticResource collectionConverter}, UpdateSourceTrigger=PropertyChanged}"/>
</Window.Resources>
<TabControl>
    <TabControl.ItemsSource>
        <CompositeCollection>
            <TabItem Header="test">
                <StackPanel>
                    <Button Content="Add new item" Click="AddNewTabItem"></Button>
                    <Button Content="Remove last item" Click="RemoveLastItem"></Button>
                </StackPanel>
            </TabItem>
            <CollectionContainer Collection="{Binding Source={StaticResource ExistingTabs}}" >
            </CollectionContainer>
        </CompositeCollection>
    </TabControl.ItemsSource>
</TabControl>

Converter:

public class CollectionConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is ObservableCollection<TestData>)
        {
            return new ObservableCollection<TabItem>(((ObservableCollection<TestData>)value).
                Select(q => q.tiTestTab));
        }
        return null;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

ReportDataSet:

public class ReportDataSet
{
    public static ObservableCollection<TestData> testData { get; set; }

    static ReportDataSet()
    {
        testData = new ObservableCollection<TestData>();
        testData.Add(new TestData()
        {
            tiTestTab = new TabItem()
            {
                Header = "test 1"
            }
        });

        testData.CollectionChanged += (s, e) => { OnStaticPropertyChanged("testData"); };
    }
    public static event EventHandler<PropertyChangedEventArgs> StaticPropertyChanged;

    protected static void OnStaticPropertyChanged(string propertyName)
    {
        var handler = StaticPropertyChanged;
        if (handler != null) handler(null, new PropertyChangedEventArgs(propertyName));
    }
}

Code-behind (for test purposes):

    private void AddNewTabItem(object sender, RoutedEventArgs e)
    {
        ReportDataSet.testData.Add(new TestData()
        {
            tiTestTab = new TabItem()
            {
                Header = "test " + (ReportDataSet.testData.Count + 1)
            }
        });
    }

    private void RemoveLastItem(object sender, RoutedEventArgs e)
    {
        if (ReportDataSet.testData.Count == 0) return;

        ReportDataSet.testData.Remove(ReportDataSet.testData.Last());
    }

Hope, it helps

Hi.. It tells "The name CollectionConverter does not exist in the namespace ....." — Gabe, Sep 06 '15 at 10:50
Did you add it, added "local" namespace and rebuilt project? =) — keymusicman, Sep 06 '15 at 10:51
Are CollectionConverter and your window in the same namespace? If not, are they in the same assembly? If not, how did you specify xmlns? — keymusicman, Sep 06 '15 at 11:01
[Here's](https://drive.google.com/file/d/0B7KFnF8l1O2UM1NSTGR1WklzakE/view?usp=sharing) my test project for you. Adding and removing tab items works fine. As you cannot share your code and do not allow me to help you, you have to search possible mistakes in your code yourself if something does not work — keymusicman, Sep 06 '15 at 11:21
You're the best, @VMaleev. Your suggestions and code work great. I really appreciate your time and effort. Solved the problem. Would you be so kind as to peek at another question I posted: http://stackoverflow.com/questions/32410249/buffled-with-setting-minimum-width-to-datagrid-column-and-then-applying-to-grid? — Gabe, Sep 06 '15 at 11:50

bounding tab control items to a PROPERTY of an ObservableCollection, with a twist

1 Answers1