title: How to notify GUI changes with INotifyPropertyChanged immediately
body: <p>I have an ObservableCollection binded to a Datagrid on my view, each element has a Bool property <code>IsSelected</code> binded to a <code>DataGridCheckBoxColumn</code> until here everything Works as a MVVM must. But my problem is that <code>INotifyPropertyChanged</code> doesn't trigger just after the user changes my <code>DataGridCheckBoxColumn</code>, it triggers only when it loses focus. </p>
  
  <p>What can I do to force the grid to notify of the change immediately, not when the column loses the focus? </p>
  
  <p>I was trying setting </p>
  
  <pre><code>NotifyOnSourceUpdated=true
  NotifyOnTargetUpdated=true
  </code></pre>
  
  <p>this is my column </p>
  
  <pre><code>&lt;DataGridCheckBoxColumn Header="{x:Static resources:Labels.TESORERIA_AplicarTodo}"
                          Binding="{Binding Path=Seleccionado,NotifyOnSourceUpdated=True,NotifyOnTargetUpdated=True,NotifyOnValidationError=True}"/&gt;
  </code></pre>