ItemsControl.ItemBindingGroup Property

Definition

Obtiene o establece el BindingGroup que se copia en cada elemento en el ItemsControl.Gets or sets the BindingGroup that is copied to each item in the ItemsControl.

public:
 property System::Windows::Data::BindingGroup ^ ItemBindingGroup { System::Windows::Data::BindingGroup ^ get(); void set(System::Windows::Data::BindingGroup ^ value); };
[System.ComponentModel.Bindable(true)]
public System.Windows.Data.BindingGroup ItemBindingGroup { get; set; }
member this.ItemBindingGroup : System.Windows.Data.BindingGroup with get, set
Public Property ItemBindingGroup As BindingGroup

Property Value

BindingGroup

BindingGroup que se copia en cada elemento en el ItemsControl.The BindingGroup that is copied to each item in the ItemsControl.

Attributes

Examples

El siguiente ejemplo forma parte de una aplicación que solicita al usuario que especifique varios clientes y asigna un representante de ventas a cada cliente y, a continuación, comprueba que el representante de ventas y el cliente pertenecen a la misma región.The following example is part of an application that prompts the user to enter multiple customers and assign a sales representative to each customer, and then checks that the sales representative and the customer belong to the same region. En el ejemplo se establece el ItemBindingGroup del ItemsControl para que el ValidationRule, AreasMatch, valide cada elemento.The example sets the ItemBindingGroup of the ItemsControl so the ValidationRule, AreasMatch, will validate each item. En el ejemplo también se crea un Label que muestra los errores de validación.The example also creates a Label that displays validation errors. Observe que el Content del Label está enlazado a un ValidationError que obtiene de la propiedad Validation.ValidationAdornerSiteForProperty.Notice that the Content of the Label is bound to a ValidationError that it gets from the Validation.ValidationAdornerSiteForProperty property. El valor de Validation.ValidationAdornerSiteForProperty es el contenedor de elementos que tiene el error.The value of Validation.ValidationAdornerSiteForProperty is the item container that has the error.

<ItemsControl Name="customerList"  ItemTemplate="{StaticResource ItemTemplate}"
              ItemsSource="{Binding}">
  <ItemsControl.ItemBindingGroup>
    <BindingGroup>
      <BindingGroup.ValidationRules>
        <src:AreasMatch/>
      </BindingGroup.ValidationRules>
    </BindingGroup>
  </ItemsControl.ItemBindingGroup>
  <ItemsControl.ItemContainerStyle>
    <Style TargetType="{x:Type ContentPresenter}">
      <Setter Property="Validation.ValidationAdornerSite"
              Value="{Binding ElementName=validationErrorReport}"/>
    </Style>
  </ItemsControl.ItemContainerStyle>
</ItemsControl>
<Label Name="validationErrorReport" 
       Content="{Binding RelativeSource={RelativeSource Self}, 
       Path=(Validation.ValidationAdornerSiteFor).(Validation.Errors)[0].ErrorContent}"
       Margin="5" Foreground="Red" HorizontalAlignment="Center"/>

En el ejemplo siguiente se obtiene el contenedor de elementos y se llama a UpdateSources en el BindingGroup del contenedor para validar los datos.The following example gets the item container and calls UpdateSources on the container's BindingGroup to validate the data. Debe validar los datos mediante una llamada a un método en el BindingGroupdel contenedor del elemento, no en el ItemBindingGroup de la ItemsControl.You must validate the data by calling a method on the item container's BindingGroup, not on the ItemBindingGroup of the ItemsControl.

void saveCustomer_Click(object sender, RoutedEventArgs e)
{
    Button btn = sender as Button;
    FrameworkElement container = (FrameworkElement) customerList.ContainerFromElement(btn);

    // If the user is trying to change an items, when another item has an error,
    // display a message and cancel the currently edited item.
    if (bindingGroupInError != null && bindingGroupInError != container.BindingGroup)
    {
        MessageBox.Show("Please correct the data in error before changing another customer");
        container.BindingGroup.CancelEdit();
        return;
    }

    if (container.BindingGroup.UpdateSources())
    {
        bindingGroupInError = null;
        MessageBox.Show("Item Saved");
    }
    else
    {
        bindingGroupInError = container.BindingGroup;
    }
}
Private Sub saveCustomer_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim btn As Button = TryCast(sender, Button)
    Dim container As FrameworkElement = CType(customerList.ContainerFromElement(btn), FrameworkElement)

    ' If the user is trying to change an items, when another item has an error,
    ' display a message and cancel the currently edited item.
    If bindingGroupInError IsNot Nothing AndAlso bindingGroupInError IsNot container.BindingGroup Then
        MessageBox.Show("Please correct the data in error before changing another customer")
        container.BindingGroup.CancelEdit()
        Return
    End If

    If container.BindingGroup.UpdateSources() Then
        bindingGroupInError = Nothing
        MessageBox.Show("Item Saved")
    Else
        bindingGroupInError = container.BindingGroup
    End If

End Sub

Remarks

Al establecer la propiedad ItemBindingGroup, cada contenedor de elementos obtiene un BindingGroup que tiene los mismos objetos ValidationRule que el ItemBindingGroup, pero las propiedades que describen los datos de los enlaces, como Items y BindingExpressions, son específicas de los datos de cada elemento de la ItemsControl.When you set the ItemBindingGroup property, each item container gets a BindingGroup that has the same ValidationRule objects as the ItemBindingGroup, but the properties that describe the data in the bindings, such as Items and BindingExpressions, are specific to the data for each item in the ItemsControl. Debe tener acceso a la BindingGroup del contenedor de elementos para realizar operaciones como validar los datos y comprobar si hay errores en un elemento.You must access the item container's BindingGroup to perform operations such as validate the data and check for errors on an item.

Applies to