Segmented textbox in WPF - wpf

Question

Is anyone aware of a free or commercial WPF control that would do something like this:
X character per box, and auto-tabbing to the next box as you complete each box? Similar to the way that license keys are entered for Microsoft products.
I don't think it would be particularly hard to do from scratch, but I'd like to avoid reinventing the wheel if a good example of this already exists.

Answer 1

WPF provides all you need except auto-tabbing to the next control. A behavior can provide that functionality and the result looks like this:
<Grid>
<Grid.Resources>
<local:KeyTextCollection x:Key="keys"/>
</Grid.Resources>
<StackPanel>
<ItemsControl ItemsSource="{StaticResource keys}" Focusable="False">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" Background="AliceBlue"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBox Text="{Binding Text}" Margin="5" MaxLength="4" Width="40">
<i:Interaction.Behaviors>
<local:TextBoxBehavior AutoTab="True" SelectOnFocus="True"/>
</i:Interaction.Behaviors>
</TextBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</Grid>
Here are the KeyText and KeyTextCollection classes (adjust to taste):
class KeyText
{
public string Text { get; set; }
}
class KeyTextCollection : List<KeyText>
{
public KeyTextCollection()
{
for (int i = 0; i < 4; i++) Add(new KeyText { Text = "" });
}
}
And here is the behavior that implements auto-tab and select-on-focus:
public class TextBoxBehavior : Behavior<TextBox>
{
public bool SelectOnFocus
{
get { return (bool)GetValue(SelectOnFocusProperty); }
set { SetValue(SelectOnFocusProperty, value); }
}
public static readonly DependencyProperty SelectOnFocusProperty =
DependencyProperty.Register("SelectOnFocus", typeof(bool), typeof(TextBoxBehavior), new UIPropertyMetadata(false));
public bool AutoTab
{
get { return (bool)GetValue(AutoTabProperty); }
set { SetValue(AutoTabProperty, value); }
}
public static readonly DependencyProperty AutoTabProperty =
DependencyProperty.Register("AutoTab", typeof(bool), typeof(TextBoxBase), new UIPropertyMetadata(false));
protected override void OnAttached()
{
AssociatedObject.PreviewGotKeyboardFocus += (s, e) =>
{
if (SelectOnFocus)
{
Action action = () => AssociatedObject.SelectAll();
AssociatedObject.Dispatcher.BeginInvoke(action, DispatcherPriority.ContextIdle);
}
};
AssociatedObject.TextChanged += (s, e) =>
{
if (AutoTab)
{
if (AssociatedObject.Text.Length == AssociatedObject.MaxLength &&
AssociatedObject.SelectionStart == AssociatedObject.MaxLength)
{
AssociatedObject.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
}
}
};
}
}
If you are not familiar with behaviors, Install the Expression Blend 4 SDK and add this namespaces:
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
and add System.Windows.Interactivity to your project.