WPF, xaml - issues with TextBlocks inside a ListView

Question

I have a ListView that I want to bind to a list of items (Items), but I want the contents displayed inside TextBlocks.

This is my xaml :

<Window.DataContext>
    <local:WindowViewModel/>
</Window.DataContext>

<Canvas Style="{StaticResource MainCanvasStyle}">
    <ListView Name="MainListView" Style="{StaticResource MainListViewStyle}" SelectionChanged="ListView_SelectionChanged">
        <TextBlock Text="{Binding Items.Number}"/>
        <TextBlock Text="{Binding Items.Type}"/>
    </ListView>
</Canvas>

And this is my VM :

class WindowViewModel
{
    /// <summary>
    /// Hides the main window if it's open.
    /// </summary>
    public ICommand HideWindowCommand
    {
        get
        {
            return new DelegateCommand
            {
                CommandAction = () => Application.Current.MainWindow.Close(),
                CanExecuteFunc = () => Application.Current.MainWindow != null
            };
        }
    }

    public WindowViewModel()
    {
        _itemHandler = new ItemHandler();
        _itemHandler.Add(new Item("Test1Name", "Test1Type"));
        _itemHandler.Add(new Item("Test2Name", "Test2Type"));
    }

    private readonly ItemHandler _itemHandler;
    public List<Item> Items
    {
        get { return _itemHandler.Items; }
    }
}
public class ItemHandler
{
    public ItemHandler()
    {
        Items = new List<Item>();
    }

    public List<Item> Items { get; private set; }

    public void Add(Item item)
    {
        Items.Add(item);
    }
}

public class Item
{
    public Item(string number, string type)
    {
        Number = number;
        Type = type;
    }

    public string Number { get; set; }
    public string Type { get; set; }
}

When I launch the program I get an error :

Operation is not valid while ItemsSource is in use. Access and modify elements with ItemsControl.ItemsSource instead.

On line

TextBlock Text="{Binding Items.Number}"

but I don't quite understand why.

I'd preferably use a canvas with TextBlocks instead of just plain TextBlocks, but that's another thing I'm not sure how to do.

I think I did, look at the edit. Besides, when I don't use TextBlocks inside the ListView and just bind ListView's ItemSoruce to the Items list the objects get displayed (ProjectName.Item) but not their contents (Numbers, Types). — user8620003

Nitin Nitin · Accepted Answer · 2018-04-18T10:43:23

Set the ItemsSource to the listview and set ItemTemplate as below:

     <ListView Name="MainListView" Style="{StaticResource MainListViewStyle}" ItemsSource="{Binding Items}" SelectionChanged="ListView_SelectionChanged">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <TextBlock Text="{Binding Number}"/>
                        <TextBlock Text="{Binding Type}"/>
                    </StackPanel>
                </DataTemplate>
            </ListView.ItemTemplate>

        </ListView>

WPF, xaml - issues with TextBlocks inside a ListView

2 Answers