Binding a DataTrigger to the IsChecked property of a checkbox

Question

I believe what I'm trying to do is "simple" enough, so I'm probably just missing something obvious.

In a DataGrid, I am trying to bind a CheckBox so that when it is checked, the Background color of its row will change. Every row has a CheckBox. I am basically implementing my own select-multiple-rows functionality (it's a product requirement, don't ask), and I have everything else working but this visual indication of a selected row.

I've read this question but where I lack my answer is what exactly to put as "BooleanPropertyOnObjectBoundToRow". I've also looked at this question and tried messing with a RelativeSource but with no luck.

I create my grid in my code-behind, but here is my current style used for rows (which has my DataTrigger defined):

<Style x:Key="MyRowStyle" TargetType="DataGridRow">
      <Style.Triggers>
           <DataTrigger Binding="{Binding IsChecked}" Value="True">
               <Setter Property="Background" Value="Blue"/>
           </DataTrigger>
      </Style.Triggers>
</Style>

Now in my code-behind, I create my DataGridTemplateColumn and use a Factory to create my checkboxes, and here is my Binding-relevant code:

Binding checkBinding = new Binding("IsChecked");
checkBinding.Mode = BindingMode.OneWayToSource;
RelativeSource relativeSource = new RelativeSource();
relativeSource.AncestorType = typeof(DataGridRow);
relativeSource.Mode = RelativeSourceMode.FindAncestor;
checkBinding.RelativeSource = relativeSource;
factory.SetBinding(CheckBox.IsCheckedProperty, checkBinding);

What may be of interest is the fact that I set the ItemsSource of my DataGrid to a DataTable, but my CheckBox column does NOT have a corresponding column in the DataTable. I simply add the template column separately, maybe this lack of underlying storage is affecting this?

In any case if you need any more info, please let me know. Thanks!

Answer 1

Here's an example that works for me using C# classes, not a DataSet.

Xaml

<Page.Resources>
    <Style x:Key="RowStyle" TargetType="{x:Type DataGridRow}">
        <Style.Triggers>
            <DataTrigger Binding="{Binding IsChecked, UpdateSourceTrigger=PropertyChanged}" Value="True">
                <Setter Property="Background" Value="Blue"/>
            </DataTrigger>
        </Style.Triggers>
    </Style>
</Page.Resources>

<Page.DataContext>
    <Samples:DataGridRowHighlightViewModels/>
</Page.DataContext>

<Grid>
    <DataGrid ItemsSource="{Binding Items}" RowStyle="{StaticResource RowStyle}" CanUserAddRows="False" AutoGenerateColumns="False">
        <DataGrid.Columns>
            <DataGridCheckBoxColumn Header="Selected" Binding="{Binding IsChecked}"/>
            <DataGridTextColumn Header="Name" Binding="{Binding Name}"/>
        </DataGrid.Columns>
    </DataGrid>
</Grid>

C#

public class DataGridRowHighlightViewModels
{
    public DataGridRowHighlightViewModels()
    {
        Items = new List<DataGridRowHighlightViewModel>
                    {
                        new DataGridRowHighlightViewModel {Name = "one"},
                        new DataGridRowHighlightViewModel {Name = "two"},
                        new DataGridRowHighlightViewModel {Name = "three"},
                        new DataGridRowHighlightViewModel {Name = "four"},
                    };
    }
    public IEnumerable<DataGridRowHighlightViewModel> Items { get; set; } 
}

// ViewModelBase and Set() give INotifyPropertyChanged support (from MVVM Light)
public class DataGridRowHighlightViewModel : ViewModelBase 
{
    private bool _isChecked;
    public bool IsChecked
    {
        get { return _isChecked; }
        set { Set(()=>IsChecked, ref _isChecked, value); }
    }

    private string _name;
    public string Name
    {
        get { return _name; }
        set { Set(()=>Name, ref _name, value); }
    }
}