WPF DataGridTextColumn Tooltip

Question

Is there a way to add tool tip to DataGridColumn header and still retain the sorting functionality. The below code doesnt work(It doesnt display the tooltip)

<toolkit:DataGridTextColumn Header="Test" Width="70" Binding="{Binding TestText}" ToolTipService.ToolTip="{Binding TestText}">

And when I use the code below

<toolkit:DataGridTemplateColumn Header="Test" Width="70">  
              <toolkit:DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <TextBlock Text="{Binding TestText}" ToolTip="{Binding TestText}"  />
                        </DataTemplate>
                    </toolkit:DataGridTemplateColumn.CellTemplate>
                </toolkit:DataGridTemplateColumn>

The column loses sorting functionality..Help!

Answer 1

When the grid creates automatic columns, it knows which field is being displayed in that column. When you create the column yourself, the data grid doesn't know what data you'll be displaying in that column and so it cannot guess which field to sort the column by. To make a column you define yourself sortable, add the SortMemberPath property to your DataGridTemplateColumn like this:

<DataGridTemplateColumn Header="Test" Width="70" SortMemberPath="TestText">
    ...
</DataGridTemplateColumn>

Answer 2

You are adding a tooltip to the column template, not to the header.

Have you tried setting the HeaderStyle property on DataGridColumn to a style that contains a template including a tooltip for the HeaderCell?

Have a look at this example too

Answer 3

Previous answers are mostly correct, however I find them overly complicated or addressing only one of the two concerns of the post.

Firstly, you can always set the SortPath property to maintain sorting for a DataGridTemplateColumn, or possibly when you want to sort on some property other than what is displayed.

Second, you do not need a DataGridTemplateColumn in order to have a ToolTip on the Column Header like the OP mentions. You might use a template column if you want to add a tooltip to the actual cell (but this probably isn't needed either). In any case, adding a ToolTip to the column header is most easily accomplished by the HeaderStyle

<DataGridTextColumn Header="Test" Binding="{Binding TestText}">
    <DataGridTextColumn.HeaderStyle>
        <Style TargetType="DataGridColumnHeader">
            <Setter Property="ToolTip" Value="Test ToolTip" />
        </Style>
    </DataGridTextColumn.HeaderStyle>
</DataGridTextColumn>

Answer 4

To get the ToolTip to display in the DataGridColumnHeader you'll need to bind the ToolTip property for it to the ToolTip of its DataGridColumn like this

<toolkit:DataGridTextColumn Header="Test"
                            Width="70"
                            Binding="{Binding TestText}"
                            ToolTipService.ToolTip="My Tooltip Text">
    <toolkit:DataGridTextColumn.HeaderStyle>
        <Style TargetType="toolkit:DataGridColumnHeader">
            <Setter Property="ToolTip"
                    Value="{Binding RelativeSource={RelativeSource Self},
                                    Path=Column.(ToolTipService.ToolTip)}"/>
        </Style>
    </toolkit:DataGridTextColumn.HeaderStyle>
</toolkit:DataGridTextColumn>