Binding a string list to a DataGridTemplateColumn TextBox

Question

If I try to do that, I get \"System.Windows.Markup.XamlParseException\".

My XAML code looks like this:

Answer 1

Additional information from exception is: Two-way binding requires Path or XPath. TextBox Text property has TwoWay binding mode by default. TwoWay bindings do not accept empty bindings like "{Binding}". Try the following.

<DataGridTemplateColumn Header="">
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <TextBox Text="{Binding Path=.}" AcceptsReturn="True" AcceptsTab="True" TextWrapping="Wrap"/>
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

I think, changing your collection type and using some custom type instead of string will be a better solution though: XAML:

<Grid>
    <DataGrid ItemsSource="{Binding ErrorLog}" AutoGenerateColumns="False" IsReadOnly="True" CanUserAddRows="False" CanUserDeleteRows="False">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding Message}" Header="Fehler" Width="*"/>
            <DataGridTemplateColumn Header="">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <TextBox Text="{Binding Message}" AcceptsReturn="True" AcceptsTab="True" TextWrapping="Wrap"/>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>
    </DataGrid>
</Grid>

Code-behind:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        DataContext = new MainViewModel();
    }
}

public class MainViewModel
{
    public ObservableCollection<Error> ErrorLog { get; set; } = new ObservableCollection<Error>
                                                                    {
                                                                        new Error("A"),
                                                                        new Error("B"),
                                                                    };
}

public class Error
{
    public Error(string message)
    {
        Message = message;
    }

    public string Message { get; set; }
}

Also consider implement INotifyPropertyChanged interface to be able to change message from view model if needed.