INotifyDataErrorInfo的不同模板

Question

我有错误对象：

/// <summary>
/// Represent error in wizard control child.
/// </summary>
public sealed class ErrorContainer
{
    /// <summary>
    /// Ctor.
    /// </summary>
    /// <param name="kind"></param>
    /// <param name="message"></param>
    public ErrorContainer(ErrorKind kind, string message)
    {
        Contract.Requires(!string.IsNullOrEmpty(message));

        Kind = kind;
        Message = message;
    }

    /// <summary>
    /// Kind of error.
    /// </summary>
    public ErrorKind Kind { get; private set; }

    /// <summary>
    /// Text to display.
    /// </summary>
    public string Message { get; private set; }

    public override string ToString()
    {
        return Message;
    }
}

/// <summary>
/// Kind of error.
/// </summary>
public enum ErrorKind
{
    /// <summary>
    /// Prevents telegram send.
    /// </summary>
    Critical = 0,

    /// <summary>
    /// Only display message.
    /// </summary>
    Warning = 1
}

我在文本框中使用INotifyDataErrorInfo和自定义样式。我以INotifyDataErrorInfo错误的形式返回ErrorContainer集合。我只想在ErrorKind为Critical时显示错误消息。下面是我尝试这样做的方法：

<Style x:Key="TextboxWithAdvancedValidationHorizontal" TargetType="{x:Type TextBox}" BasedOn="{StaticResource {x:Type TextBox}}">
  <Style.Triggers>
    <DataTrigger Binding="{Binding CurrentItem.ErrorContent.Kind}" Value="{x:Static kn01:ErrorKind.Critical}">
      <Setter Property="Validation.ErrorTemplate">
        <Setter.Value>
          <ControlTemplate>
            <StackPanel Orientation="Horizontal" SnapsToDevicePixels="True">
              <Border BorderBrush="Salmon" Background="#11FF0000" IsHitTestVisible="False">
                <AdornedElementPlaceholder />
              </Border>
              <StackPanel Orientation="Horizontal">
                <Polygon  VerticalAlignment="Center" Points="0,4 4,0 4,8" Fill="Salmon" Stretch="Fill" Stroke="Salmon" StrokeThickness="2" />
                <Border Background="Salmon" Padding="4" Margin="-1,0,0,0">
                  <TextBlock HorizontalAlignment="Center" Foreground="White" FontWeight="Bold" Margin="2,-1,0,1" Text="{Binding CurrentItem.ErrorContent}" />
                </Border>
              </StackPanel>
            </StackPanel>
          </ControlTemplate>
        </Setter.Value>
      </Setter>
    </DataTrigger>
  </Style.Triggers>
</Style>

然而，它根本不起作用，并使用默认的错误模板。

Answer 1

不要将Validation.ErrorTemplate模板放在触发器中。

必须在错误发生前设置Validation.ErrorTemplate。

如果您需要不同的错误模板，请在ErrorTemplate中使用触发器。或者，您可以将ContentPresenter与ContentTemplateSelector一起使用。

<Style x:Key="TextboxWithAdvancedValidationHorizontal" TargetType="TextBox">
  <Setter Property="Validation.ErrorTemplate">
    <Setter.Value>

          <ControlTemplate>
            <StackPanel Orientation="Horizontal" SnapsToDevicePixels="True">
              <Border BorderBrush="Salmon" Background="#11FF0000" IsHitTestVisible="False">
                <AdornedElementPlaceholder />
              </Border>
            </StackPanel>

            <ControlTemplate.Triggers>
              <DataTrigger Binding="...">
                <!-- add you custom UI logic here -->
              </DataTrigger>
            </ControlTemplate.Triggers>
          </ControlTemplate>

    </Setter.Value>
  </Setter>
</Style>

Answer 2

你有没有试过用断点调试它来检查你的绑定？此外，我认为你以错误的方式瞄准了你的风格。下面是另一个可能有帮助的答案：https://stackoverflow.com/a/4133971/6563936