Question

I would like to set up a datagrid so that whenever an item is added to its itemssource the datagrid scrolls down to show the last item.

The datagrid is inside a datatemplate, so i cannot set the X:name property and access it directly from the codebehind.

What I have in mind is to use a datagrid event that fires when a row is added and has the grid scroll itself.

Here’s some psuedo code that outlines how I have things set up:

---

UI.XAML exerpt

<TabControl ItemsSource="{Binding Parents}" x:Name="ProductsTab">
    <TabControl.ItemTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding Key}"/>
        </DataTemplate>
    </TabControl.ItemTemplate>
    <TabControl.ContentTemplate>
        <DataTemplate>
            <DataGrid Margin="5" ItemsSource="{Binding Value.Children}">
                <DataGrid.Columns>
                    <Column Column definitions removed for your sanity/>
                </DataGrid.Columns>
            </DataGrid>
        </DataTemplate>
    </TabControl.ContentTemplate>
</TabControl>

---

UI.XAML.CS exerpt

public class UI
{
    //Thanks to Dr. WPF for the ObservableDictionary class
    public ObservableDictionary<string, Parent> Parents {get; set;}
}

---

Parent.CS

public class parent
{
    public ObservableCollection<Child> Children {get; set;}
}

---

The datagrids are not editable.

In case you’re wondering, I have read the post “How to autoscroll on WPF datagrid” the code in that post would work for me if I could find an event that fires whenever an item is added to the datagrid itemssource.

Any Ideas?

Answer 1

Combine the autoscrolling idea with the idea from this question or this MSDN thread: instead of listening to your grid’s event to detect row additions, listen to the events from the ItemsSource.

Edit: Since you don’t like that suggestion, you could try hooking LoadingRow, but I strongly suspect this will require EnableRowVirtualization = false in order to work (I haven’t tried it). If your collection gets large, turning off row virutalization opens up the possibility of a serious performance hit.