title: DataGrid catch cell value changed event with a single click on UpdateSourceTrigger = SourceUpdated
body: <p>I'm struggling to catch an event with a DataGrid. What I want to achieve is that when the user clicks ONCE on a checkbox of a datagrid cell, an event fires and I can get the current cell value. However the CellChangedEvent fires only when the selection changes, and the CellEditingEvent either fires when the cell loses focus, OR never fires. It never fires if I try to make a checkbox modificable with a single click, by doing the following:</p>
  
  <pre><code>&lt;DataGrid Grid.ColumnSpan="2" Grid.Row="1" Grid.Column="0" AutoGenerateColumns="True" ItemsSource="{Binding MasterDataTable, Mode=TwoWay}" CanUserAddRows="False" Margin="10 5" CurrentCellChanged="DataGrid_CurrentCellChanged"&gt;
              &lt;DataGrid.Resources&gt;
                  &lt;Style TargetType="DataGridCell"&gt;
                      &lt;Style.Triggers&gt;
                          &lt;Trigger Property="IsMouseOver" Value="True"&gt;
                              &lt;Setter Property="IsEditing" Value="True" /&gt;
                          &lt;/Trigger&gt;
                      &lt;/Style.Triggers&gt;
                  &lt;/Style&gt;
              &lt;/DataGrid.Resources&gt;
          &lt;/DataGrid&gt;
  </code></pre>
  
  <p>How can I call a method as soon as the user clicks on a checkbox inside a cell?
  Thanks in advance.</p>