How do I stop binding properties from updating?

Question

I have a dialog that pops up over the main screen (it\'s actually a user control that appears on the page as per the application demo from Billy Hollis) in my application that h

Answer 1

You could use a BindingGroup :

...
<StackPanel Name="panel">
    <StackPanel.BindingGroup>
        <BindingGroup Name="bindingGroup"/>
    </StackPanel.BindingGroup>
    <TextBox Text="{Binding Foo}"/>
    <TextBox Text="{Binding Bar}"/>
    <Button Name="btnSubmit" Content="Submit" OnClick="btnSubmit_Click"/>
    <Button Name="btnCancel" Content="Cancel" OnClick="btnCancel_Click"/>
</StackPanel>
...

Code behind :

private void UserControl_Loaded(object sender, RoutedEventArgs e)
{
    panel.BindingGroup.BeginEdit();
}

private void btnSubmit_Click(object sender, RoutedEventArgs e)
{
    panel.BindingGroup.CommitEdit();
    panel.BindingGroup.BeginEdit();
}

private void btnCancel_Click(object sender, RoutedEventArgs e)
{
    panel.BindingGroup.CancelEdit();
    panel.BindingGroup.BeginEdit();
}

Answer 2

Have a look at the Binding.UpdateSourceTrigger property.

You can set the Binding in your dialog like so

<TextBox Name="myTextBox" 
    Text={Binding Path=MyProperty, UpdateSourceTrigger=Explicit} />

And then call the UpdateSource method in your button save event

myTextBox.GetBindingExpression(TextBox.TextProperty).UpdateSource();

Once you've called UpdateSource the source object will be updated with the value from the TextBox

Answer 3

I also choose to use BindingGroup. But instead of BeginEdit() / CommitEdit() / CancelEdit() pattern I call UpdateSource() explicitly on all the bindings associated with BindingGroup. This approach allows me to add only one event handler instead of 3.

private void OkButton_Click(object sender, RoutedEventArgs e)
{
    CommitChanges();
    DialogResult = true;
    Close();
}

private void CommitChanges()
{
    foreach (var bindingExpression in this.BindingGroup.BindingExpressions)
    {
        bindingExpression.UpdateSource();
    }
}