blocks|key|103616|text|await+CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
++++++++++++CoreDispatcherPriority.Normal,
++++++++++++()+=>+{+//+your+code+should+be+here});|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|103617|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>await CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
 CoreDispatcherPriority.Normal,
 () =&gt; { // your code should be here});
</code></pre>

blocks|key|320589|text|实际上，我会提出这样的建议：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|320590|return+(Window.Current+==+null)+?+
++++CoreApplication.MainView.CoreWindow.Dispatcher+:+
++++CoreApplication.GetCurrentView().CoreWindow.Dispatcher|code-block|syntax|javascript|320591|这样，如果你打开了另一个视图/窗口，你就不会把调度员搞糊涂了……|320592|这个小宝石会检查是否有窗口。如果没有，则使用MainView的调度程序。如果有视图，则使用该视图的调度程序。|320593|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Actually, I would propose something in the line of this:

<pre><code>return (Window.Current == null) ? 
 CoreApplication.MainView.CoreWindow.Dispatcher : 
 CoreApplication.GetCurrentView().CoreWindow.Dispatcher
</code></pre>

That way, should you have openend another View/Window, you won't get the Dispatchers confused...

This little gem checks whether there is even a Window. If none, use the MainView's Dispatcher. If there is a view, use that one's Dispatcher.

blocks|key|320639|text|虽然这是一个旧线程，但我想引起人们对开发人员可能遇到的一个问题的关注，这个问题影响了我，使我在大型UWP应用程序中调试变得极其困难。在我的例子中，我在2014年根据上面的建议重构了以下代码，但偶尔会受到应用程序冻结的困扰，这些冻结本质上是随机的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|320640|public+static+class+DispatcherHelper
{
++++public+static+Task+RunOnUIThreadAsync(Action+action)
++++{
++++++++return+RunOnUIThreadAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,+action);
++++}

++++public+static+async+Task+RunOnUIThreadAsync(Windows.UI.Core.CoreDispatcherPriority+priority,+Action+action)
++++{
++++++++try
++++++++{
++++++++++++await+returnDispatcher().RunAsync(priority,+()+=>
++++++++++++{
++++++++++++++++action();
++++++++++++});
++++++++}
++++++++catch+(Exception+ex)
++++++++{
++++++++++++var+noawait+=+ExceptionHandler.HandleException(ex,+false);
++++++++}
++++}

++++private+static+Windows.UI.Core.CoreDispatcher+returnDispatcher()
++++{
++++++++return+(Windows.UI.Xaml.Window.Current+==+null)+?
++++++++++++CoreApplication.MainView.CoreWindow.Dispatcher+:
++++++++++++CoreApplication.GetCurrentView().CoreWindow.Dispatcher;
++++}
}|code-block|syntax|javascript|320641|在上面的代码中，我使用了一个静态类来允许在整个应用程序中调用Dispatcher+--只允许一个调用。在95%25的时间里，即使通过QA回归，一切都是正常的，但客户会时不时地报告一个问题。解决方案是包含下面的调用，而不是在实际页面中使用静态调用。|320642|++++++++++++await+Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,+()+=>
++++++++++++{+

++++++++++++});|320643|当我需要确保UI线程是从App.xaml.cs或我的单例NavigationService调用的时候，情况就不是这样了，它们处理堆栈上的推送/弹出。dispatcher显然忘记了调用了哪个UI，因为每个页面都有自己的UI线程，而堆栈却有各种从MessageBus触发的消息。|320644|希望这能帮助其他可能受到影响的人，也是我认为每个平台都会通过发布一个涵盖最佳实践的完整项目来为其开发人员提供服务的地方。|320645|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

While this is an old thread, I wanted to draw attention to a possible issue developers may run across which impacted me and made it extremely difficult to debug in large UWP apps. In my case, I refactored the following code from the suggestions above back in 2014 but would occasionally be plagued with the occasional app freezes that were random in nature.

<pre><code>public static class DispatcherHelper
{
 public static Task RunOnUIThreadAsync(Action action)
 {
 return RunOnUIThreadAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, action);
 }

 public static async Task RunOnUIThreadAsync(Windows.UI.Core.CoreDispatcherPriority priority, Action action)
 {
 try
 {
 await returnDispatcher().RunAsync(priority, () =&gt;
 {
 action();
 });
 }
 catch (Exception ex)
 {
 var noawait = ExceptionHandler.HandleException(ex, false);
 }
 }

 private static Windows.UI.Core.CoreDispatcher returnDispatcher()
 {
 return (Windows.UI.Xaml.Window.Current == null) ?
 CoreApplication.MainView.CoreWindow.Dispatcher :
 CoreApplication.GetCurrentView().CoreWindow.Dispatcher;
 }
}
</code></pre>

From the above, I had used a static class to allow the calling of the Dispatcher through-out the application - allowing for a single call. For 95% of the time, everything was fine even through QA regression but clients would report an issue every now and then. The solution was to include the call below, not using a static call in the actual pages.

<pre><code> await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =&gt;
 { 

 });
</code></pre>

This is not the case when I need to ensure the UI Thread was called from App.xaml.cs or my Singleton NavigationService which handled pushing/popping on to the stack. The dispatcher apparently was losing track of which UI Thread was called, since each page has it's own UI thread, when the stack had a variety of Messages triggering from the MessageBus.

Hope this helps others that may be impacted and it is also where I think each platform would do a service to their developers by publishing a complete project covering the best practices.

I'm building a Windows Store app, and I have some code that needs to be posted to the UI thread.

For that, i'd like to retrieve the CoreDispatcher and use it to post the code.

It seems that there are a few ways to do so:

<pre><code>// First way
Windows.ApplicationModel.Core.CoreApplication.GetCurrentView().CoreWindow.Dispatcher;

// Second way
Window.Current.Dispatcher;
</code></pre>

I wonder which one is correct? or if both are equivalent?

Correct way to get the CoreDispatcher in a Windows Store app

Windows

我正在构建一个Windows应用商店应用程序，并且我有一些代码需要发布到UI线程。为此，我想检索CoreDispatcher并使用它来发布代码。似乎有几种方法可以做到这一点：// First wayWindows.ApplicationModel.Core.CoreApplication.GetCurrentView(...

问在Windows应用商店应用中获取CoreDispatcher的正确方法
EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在Windows应用商店应用中获取CoreDispatcher的正确方法EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在Windows应用商店应用中获取CoreDispatcher的正确方法
EN