c# - ToggleSwitch.On和OffContent不更新

我试图基于从UWP的本地设置缓存（不是OnContent属性）检索的值来更新三个ToggleSwitches的OffContent和ToggleSwitch.IsOn。请注意，我正在外部线程上执行此操作。

这是我当前的代码：

ApplicationDataContainer localSettings = ApplicationData.Current.LocalSettings;
public async void updateUI()
{
    await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
    {
        // set Test1 state in UI
        toggleSwitchTest1.OnContent = (Convert.ToBoolean(localSettings.Values["Test1"])) ? "It is: On" : "It is: Off";
        toggleSwitchTest1.OffContent = toggleSwitchTest1.OnContent;

        // set Test2 state in UI
        toggleSwitchTest2.OnContent = (Convert.ToBoolean(localSettings.Values["Test2"])) ? "It is: On" : "It is: Off";
        toggleSwitchTest2.OffContent = toggleSwitchTest2.OnContent;

        // set Test3 state in UI
        toggleSwitchTest3.OnContent = (Convert.ToBoolean(localSettings.Values["Test3"])) ? "It is: On" : "It is: Off";
        toggleSwitchTest3.OffContent = toggleSwitchTest3.OnContent;
     });
}

我也尝试使用普通的Boolean值作为传递给该方法的参数来执行此操作。或者Boolean值只是在类的开头在公共构造函数之前声明并进行设置。这也不起作用。

请让我知道是否需要其他代码。

我究竟做错了什么？

编辑

我通过简单地调用它来在某处调用updateUI方法：updateUI()

编辑2

ToggleSwitches' XAML构造函数代码：

<ToggleSwitch x:Name="toggleSwitchTest1" OffContent="It is" OnContent="It is" HorizontalAlignment="Left" Margin="19,84,0,0" VerticalAlignment="Top" IsOn="False"/>
<ToggleSwitch x:Name="toggleSwitchTest2" OffContent="It is" OnContent="It is" HorizontalAlignment="Left" Margin="19,116,0,0" VerticalAlignment="Top" IsOn="False"/>
<ToggleSwitch x:Name="toggleSwitchTest3" OffContent="It is" OnContent="It is" HorizontalAlignment="Left" Margin="19,148,0,0" VerticalAlignment="Top" IsOn="False"/>

最佳答案

如果您从未将值应用于null，它将获得localSettings.Values["xxx"]值。如果value为null，则Convert.ToBoolean方法返回false。所有toggleSwitchTest OnConten将被设置为：关。

我发现您使用toggleSwitchTest1.OffContent = toggleSwitchTest1.OnContent;它将导致OffContent和OnConten变为相同的值。

await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
    var value = localSettings.Values["Test1"];
    // set Test1 state in UI
    toggleSwitchTest1.OnContent = (Convert.ToBoolean(localSettings.Values["Test1"])) ? "It is: On" : "It is: Off";
    // toggleSwitchTest1.IsOn = Convert.ToBoolean(localSettings.Values["Test1"]);
    toggleSwitchTest1.OffContent = !(Convert.ToBoolean(localSettings.Values["Test1"])) ? "It is: On" : "It is: Off";

    // set Test2 state in UI
    toggleSwitchTest2.OnContent = (Convert.ToBoolean(localSettings.Values["Test2"])) ? "It is: On" : "It is: Off";
    //  toggleSwitchTest2.IsOn= Convert.ToBoolean(localSettings.Values["Test2"]);
    toggleSwitchTest2.OffContent = !(Convert.ToBoolean(localSettings.Values["Test2"])) ? "It is: On" : "It is: Off";

    // set Test3 state in UI
    toggleSwitchTest3.OnContent = (Convert.ToBoolean(localSettings.Values["Test3"])) ? "It is: On" : "It is: Off";
    //   toggleSwitchTest3.IsOn= Convert.ToBoolean(localSettings.Values["Test3"]);
    toggleSwitchTest3.OffContent = !(Convert.ToBoolean(localSettings.Values["Test3"])) ? "It is: On" : "It is: Off";
});

尽管您可以使用上述代码更改off和on内容，但这将导致逻辑​​混乱。我建议您在xaml之前的内容中进行切换，然后将IsOn属性与localsetting值绑定。

toggleSwitchTest1.IsOn = Convert.ToBoolean(localSettings.Values["Test1"]);

编辑1

由于AppServiceConnection方法无法访问UI，因此尝试从这样的方法更改UI（即使使用Dispatcher时）也无效。

而是从可以通过ApplicationData.Current.DataChanged调用的方法或事件（如ApplicationData.Current.SignalDataChange()）中调用它。