title: WPF combo box update source trigger
body: <p>I've added triggers for combobox, i.e. </p>
  
  <ul>
  <li><p>When combo box is 'Disabled' then 'Text' property should set to '1'
  and added updatesourcetrigger to property changed.</p></li>
  <li><p>When combo box is 'Enabled' then 'Text' property should be selected one and added
  update source trigger to property changed.</p></li>
  </ul>
  
  <p>But the problem is I'm unable to call the update source trigger when combo box is Disabled and 'Text' property is set to '1'.</p>
  
  <p>Below is the XAML code snippet:</p>
  
  <pre><code>&lt;ComboBox Name="cmbIntervals"
                          Grid.Row="5"
                          Grid.Column="1"
                          Width="150"
                          HorizontalAlignment="Left"
                          VerticalAlignment="Top"
                          IsEnabled="{Binding ElementName=chkRollingInterval,
                                                Path=IsChecked}"
                          ItemsSource="{Binding Source={x:Static es:MasterParameters.Instance},
                                                  Path=NoOfIntervals}" 
                          Tag="{Binding Path=[NoOfIntervals], Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                          &gt;
                    &lt;ComboBox.Style&gt;
                      &lt;Style TargetType="{x:Type ComboBox}"&gt;
                        &lt;Style.Triggers&gt;
                          &lt;Trigger Property="IsEnabled" Value="False"&gt;
                          &lt;Setter Property="Text" Value="1"/&gt;
                          &lt;Setter Property="Text" Value="{Binding RelativeSource={RelativeSource Self}, Path=Tag, Mode=TwoWay, UpdateSourceTrigger=Default}"/&gt;
                        &lt;/Trigger&gt;
                        &lt;Trigger Property="IsEnabled" Value="True"&gt;
                          &lt;Setter Property="Text" Value="{Binding RelativeSource={RelativeSource Self}, Path=Tag, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/&gt;
                        &lt;/Trigger&gt;
                        &lt;/Style.Triggers&gt;
                     &lt;/Style&gt;
                  &lt;/ComboBox.Style&gt;
                &lt;/ComboBox&gt;
  </code></pre>
  
  <p>From above XAML code when ever i updated 'Text' property to '1' for combo box 'Disabeld' mode i need to update this '1' value to the source property i.e. 'Tag' and from there to 'NoOfIntervals' but it doesn't happening.</p>
  
  <p>Thanks,
  Nag</p>