在WinRT中的UI线程上运行代码

Question

如何在WinRT(Windows 8 Metro)中的UI线程上运行代码？

该Invoke方法不存在.

Answer 1

从非UI线程直接获取CoreWindow更容易.以下代码可以在任何地方使用,即使是GetForCurrentThread()或Window.Current返回null.

CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
    <lambda for your code which should run on the UI thread>);

例如:

CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal,
    () =>
    {
        // Your UI update code goes here!
    });

您需要引用Windows.ApplicationModel.Core命名空间:

using Windows.ApplicationModel.Core;

Answer 2

使用:

从您的UI线程,执行:

var dispatcher = Windows.UI.Core.CoreWindow.GetForCurrentThread().Dispatcher;

从你的背景(非UI线程)

dispatcher.RunAsync(DispatcherPriority.Normal, 
    <lambda for your code which should run on the UI thread>);

这应该适用于CP和后期版本.

Answer 3

使用:

this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => Frame.Navigate(typeof(Welcome), this));

这个对我有用.

Answer 4

在我看来,这是一种更容易的方法.

获取与UI关联的TaskScheduler.

    var UISyncContext = TaskScheduler.FromCurrentSynchronizationContext();

然后在上面的UISyncContext上启动一个新任务.

    Task.Factory.StartNew(() => { /* Do your UI stuff here; */}, new System.Threading.CancellationToken(), TaskCreationOptions.PreferFairness, UISyncContext);