Question

我正在使用带有 TextBlock 元素的 UserControl 进行WPF应用程序。这些元素的内容取决于视图模型中的枚举（成功，待定，错误等）。

以下是TextBlock的不同状态的一些示例：

示例1 - 简单

<TextBlock>
  Please wait
</TextBlock>

示例2 - 使用超链接

<TextBlock>
  Searching for item. <Hyperlink Command="{Binding DetailsCommand}">Link to details</Hyperlink>
</TextBlock>

示例3 - 使用换行符

<TextBlock>
  The content has been uploaded<LineBreak />
  The item is not ready to use
</TextBlock>

根据视图模型中枚举的状态，动态更改此元素内容的最佳方法是什么？如果我将Text属性绑定到视图模型中的字符串，我认为我不能插入像 Hyperlink ， LineBreak 等子元素。有哪些选项我有吗？

Answer 1

我会用TemplateSelector实现它：

public class TemplSelector : DataTemplateSelector
{
public override DataTemplate SelectTemplate(object item, DependencyObject container)
{
    var element = container as FrameworkElement;

    if (element != null && item != null)
    {
        var vm = (ViewModel)item;

        if (vm.YourEnum == 1)
            return element.FindResource("templ1") as DataTemplate;
        else if (vm.YourEnum == 0)
            return element.FindResource("templ0") as DataTemplate;
    }

    return null;
}
}
<Window.Resources>
    <local:TemplSelector x:Key="templSel"/>        
</Window.Resources>
<ContentPresenter ContentTemplateSelector="{StaticResource templSel}" Content="{Binding ViewModel}">
    <ContentPresenter.Resources>
        <DataTemplate x:Key="templ0">
            <TextBlock>
                Please wait
            </TextBlock>
        </DataTemplate>
        <DataTemplate x:Key="templ1">
            <TextBlock>
                Searching for item. <Hyperlink Command="{Binding DetailsCommand}">Link to details</Hyperlink>
            </TextBlock>
        </DataTemplate>
    </ContentPresenter.Resources>
</ContentPresenter>

Answer 2

您可以使用Label作为主机，并根据触发器

设置模板

    <Label>
        <Label.Style>
            <Style TargetType="Label">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding YourEnum}" Value="something">
                        <Setter Property="Template">
                            <Setter.Value>
                                <ControlTemplate>
                                    <TextBlock>
                                        Please wait
                                    </TextBlock>
                                </ControlTemplate>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding YourEnum}" Value="somethingElse">
                        <Setter Property="Template">
                            <Setter.Value>
                                <ControlTemplate>
                                    <TextBlock>
                                        Searching for item. <Hyperlink Command="{Binding DetailsCommand}">Link to details</Hyperlink>
                                    </TextBlock>
                                </ControlTemplate>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding YourEnum}" Value="else">
                        <Setter Property="Template">
                            <Setter.Value>
                                <ControlTemplate>
                                    <TextBlock>
                                        The content has been uploaded<LineBreak />
                                        The item is not ready to use
                                    </TextBlock>
                                </ControlTemplate>
                            </Setter.Value>
                        </Setter>
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </Label.Style>
    </Label>

动态更新TextBlock内容的最佳实践

2 个答案: