How do I get the UI thread’s Dispatcher?
You can grab the UI Dispatcher from the static application instance: Application.Current.Dispatcher You may want to check Application.Current for null first, as it can be cleared during a shutdown sequence.
dispatcher
WPF Dispatcher {“The calling thread cannot access this object because a different thread owns it.”}
Just in case you want the object to be shared among different threads then always create that object on UI thread. Later when you want to access the object, you can check if you have access to object. If you dont have access, re-invoke the function with UI thread access. example code below: private void … Read more
Force redraw before long running operations
The following code will do what you’re looking for. However I would not use it. Use the BackgroundWorker class for long time operations. It’s easy to use and very stable. Here the code: public static void ProcessUITasks() { DispatcherFrame frame = new DispatcherFrame(); Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background, new DispatcherOperationCallback(delegate(object parameter) { frame.Continue = false; return null; }), null); … Read more
How to forward request from servlet to action of struts2?
In order to do this you may also need to set the filter to run on FORWARD (and INCLUDE as your code shows, although you state you want a FORWARD): <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> <dispatcher>REQUEST</dispatcher> <dispatcher>FORWARD</dispatcher> <dispatcher>INCLUDE</dispatcher> <!– If you want includes as well –> </filter-mapping>
Ensuring that things run on the UI thread in WPF
Going over each of your questions, one by one: Not quite; you should only invoke onto the UI thread when necessary. See #2. Yes, it does matter. You should not just automatically Invoke everything. The key is to only invoke onto the UI thread if necessary. To do this, you can use the Dispatcher.CheckAccess method. … Read more
WPF BackgroundWorker vs. Dispatcher
The main difference between the Dispatcher and other threading methods is that the Dispatcher is not actually multi-threaded. The Dispatcher governs the controls, which need a single thread to function properly; the BeginInvoke method of the Dispatcher queues events for later execution (depending on priority etc.), but still on the same thread. BackgroundWorker on the … Read more
Dispatcher Invoke(…) vs BeginInvoke(…) confusion
When you use Dispatcher.BeginInvoke it means that it schedules the given action for execution in the UI thread at a later point in time, and then returns control to allow the current thread to continue executing. Invoke blocks the caller until the scheduled action finishes. When you use BeginInvoke your loop is going to run … Read more
Using the C# Dispatcher in WPF Applications
Your app has a main UI thread (usually ManagedThreadId==1). Typically in a chat app your events will come in on other threads (either dedicated socket listen threads or thread pool threads from listening code). If you want to update the UI from an event that gets pull on some other thread you must use the … Read more
“The calling thread must be STA, because many UI components require this” error when creating a WPF pop-up Window in thread
For the thread that you’re trying to start the GUI element in, you need to set the apartment state of the thread to STA BEFORE you start it. Example: myThread.SetApartmentState(ApartmentState.STA); myThread.Start();
Correct way to get the CoreDispatcher in a Windows Store app
This is the preferred way: Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => { // Your UI update code goes here! }); The advantage this has is that it gets the main CoreApplicationView and so is always available. More details here. There are two alternatives which you could use. First alternative Windows.ApplicationModel.Core.CoreApplication.GetCurrentView().CoreWindow.Dispatcher This gets the active view for the app, … Read more