winrt-xaml - Windows phone 8.1 中带有 VisualStates 的 DataTrigger

Question

我正在尝试将旧的 Window phone 7.5 Silverlight 应用程序转换为新的 WinRT Universal 应用程序，但这段代码有问题：

<Style TargetType="Button">
    <Setter Property="Visibility" Value="Collapsed"/>
    <Style.Triggers>
        <DataTrigger Binding="{Binding Active}" Value="True">
            <Setter Property="Visibility" Value="Visible"/>
        </DataTrigger>
    </Style.Triggers>
</Style>

我使用 DataTrigger 根据绑定值设置控件的可见性。

在 Windows Phone 8.1 winrt 应用程序中，此功能已失效。我已经尝试使用 VisualStates 来实现相同的功能，但我无法弄清楚。任何人都可以帮助我或以良好的榜样指导我。我被困在这里...

Answer 1

DataTriggers are not available currently in WinRT, you have couple of options instead:

• use VisualStateManager,

• use Behaviours managed API, for example like this:

  <Button xmlns:i="using:Microsoft.Xaml.Interactivity"
          xmlns:ic="using:Microsoft.Xaml.Interactions.Core">
      <Button.Style>
          <Style TargetType="Button">
              <Setter Property="Visibility" Value="Collapsed"/>
          </Style>
      </Button.Style>
      <i:Interaction.Behaviors>
          <ic:DataTriggerBehavior Binding="{Binding Active}" Value="True" ComparisonCondition="Equal">
              <ic:ChangePropertyAction PropertyName="Visibility" Value="Visible"/>
          </ic:DataTriggerBehavior>
      </i:Interaction.Behaviors>
  </Button>
  

• or you can just use binding with apropriate converter:

  <Button Visibility="{Binding Active, Converter={StaticResource BoolToVisibility}}"/>