wpf datagrid checkbox column header de/selects all

I'm trying to create a datagrid with a checkbox column that has a header with a checkbox that selects and deselects the rows' checkboxes. Also I'm attempting to do it with no behind code. So far I've been partialy successful in that I used the datagrid's tag as a middle man in the binding, and could de/select the rows' checkboxes from the header checkbox using data triggers but once I check a row the binding in that row 'dies' and it is no longer effected by the header. Also, I already tried it with one way bindings instead of data triggers and got the same result... Does anyone know of a way to keep the binding alive or pheraps another to achive the effect I'm looking for inxaml only.

header:

<CheckBox IsChecked="{binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}, Mode=FindAncestor}, Path=Tag}"/>

column template:

<CheckBox>
    <CheckBox.Style>
        <Style TargetType="{x:Type CheckBox}">
            <Style.Triggers>
                <DataTrigger Binding="{binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}, Mode=FindAncestor}, Path=Tag}" Value="True">
                    <Setter Property="IsChecked" Value="True"/>
              开发者_JAVA百科  </DataTrigger>
                <DataTrigger Binding="{binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}, Mode=FindAncestor}, Path=Tag}" Value="False">
                    <Setter Property="IsChecked" Value="False"/>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </CheckBox.Style>
</CheckBox>

That is actually very good idea to solve that problem. I can't see why that shouldn't work.

That said, there are a few things to try:

Place your header checkbox and the row checkbox on a window normally (not inside a DataGrid) to see what effect that has.

The other option is to try naming the Header checkbox (for example <CheckBox Name="cbxHeader") and then binding to it with {Binding ElementName=cbxHeader Path=Tag}.

Also, check the "Output" window in Visual Studio while you are testing (while it is running, Debug > Windows > Output; it might appear empty but just scroll up) for any messages about why the bindings are failing.

You can also use a bogus ValueConverter to try and see if the bindings are still firing.