Configuring the Behavior on User Input (xamComboEditor)

The xamComboEditor™ control’s CustomValueEnteredAction property allows you to specify how the control will behave when your end user types in the control’s text box. This property works when xamComboEditor is in edit mode.

The CustomValueEnteredActions enumeration allows for three behaviors.

Ignore: Default; if the character that you are typing does not match the filter criteria (or StartsWith criteria if you haven’t specified any filter criteria), then the control won’t allow you to continue typing. The invalid values will be automatically removed from the text box.
Allow: This option allows you to type data but the typed text will not be included in the items collection.
Add: If the value you typed is not in the underlying items collection, this new value will be added in it. The DataObjectRequested, ItemAdding and ItemAdded events will be triggered.

Note	Note In case of a collection with fixed capacity (e.g. Array), the `CustomValueEnteredAction` `Add` is not applicable.

The following example shows how you can configure this property.

In XAML:

<ig:XamComboEditor
    x:Name="comboEditor"
    Height="30"
    Width="300"
    ItemsSource="{Binding Source={StaticResource DataUtil}, Path=Products}"
    DisplayMemberPath="ProductName"
    IsEditable="True"
    CustomValueEnteredAction="Add" />

In Visual Basic:

Private Sub UserControl_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
    ...
    Dim comboEditor As New XamComboEditor()
    ...
    comboEditor.IsEditable = True
    comboEditor.CustomValueEnteredAction = CustomValueEnteredActions.Add
    ...
End Sub

In C#:

private void UserControl_Loaded(object sender, RoutedEventArgs e)
{
...
XamComboEditor comboEditor = new XamComboEditor();
...
comboEditor.IsEditable = true;
comboEditor.CustomValueEnteredAction = CustomValueEnteredActions.Add;
...
}

Events

The DataObjectRequested event is raised when xamComboEditor needs to create a new data object for the item you attempt to add in the items collection.

The ItemAdding event is raised when an item is going to be added in the control’s underlying ItemsSource. This event can be canceled. During this event, the entered value can be verified and after that added or cancelled.

The ItemAdded event is raised when the item has been added in the ItemsSource of the xamComboEditor control.

The following example shows how you can validate and cancel entered values during the ItemAdding event.

In Visual Basic:

Private Sub UserControl_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
    ' Adds event handler for the ItemAdding event
    AddHandler comboEditor.ItemAdding, AddressOf _ItemAdding
End Sub
Private Sub _ItemAdding(ByVal sender As Object, ByVal e As ComboItemAddingEventArgs)
    ' Gets the business object
    Dim product As Product = DirectCast(e.Item.Data, Product)
    Dim name As String = product.ProductName
    ' Validates the size of the entered product name
    ' If the name is less than 5 characters, the event will be canceled
    If name.Length < 5 Then
        e.Cancel = True
    End If
End Sub

In C#:

private void UserControl_Loaded(object sender, RoutedEventArgs e)
{
    // Adds event handler for the ItemAdding event
    comboEditor.ItemAdding += new EventHandler<ComboItemAddingEventArgs>(_ItemAdding);
}
private void _ItemAdding(object sender, ComboItemAddingEventArgs e)
{
    // Gets the business object
    Product product = (Product)e.Item.Data;
    string name = product.ProductName;
    // Validates the size of the entered product name
    // If the name is less than 5 characters, the event will be canceled
    if (name.Length < 5)
    {
        e.Cancel=true;
    }
}

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Configuring the Behavior on User Input (xamComboEditor)

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