在不同的线程中安装低级鼠标钩

Question

I need to install a WH_KEYBOARD_LL hook in my WPF application, that by itself is not a big problem. However I need to install it in a thread other than my main application thread because otherwise the cursor will freeze when the UI thread is busy. I have read this article and this SO question, but it is not quite working yet. A comment in the question suggest me to start an Application in the thread that I create the hook, but then I get and exception saying I can't start 2 applications in the same AppDomain. Are there any solutions to this or is there another, easier way to install the hook in another thread?

Answer 1

You can create a new thread with a WPF dispatcher using this code:

public class DispatcherBuilder : IBuilder<Dispatcher>
{
    public Dispatcher Build()
    {
        Dispatcher dispatcher = null;
        var manualResetEvent = new ManualResetEvent(false);
        var thread = new Thread(() =>
            {
                dispatcher = Dispatcher.CurrentDispatcher;
                var synchronizationContext = new DispatcherSynchronizationContext(dispatcher);
                SynchronizationContext.SetSynchronizationContext(synchronizationContext);

                manualResetEvent.Set();
                Dispatcher.Run();
            });
        thread.Start();
        manualResetEvent.WaitOne();
        manualResetEvent.Dispose();
        return dispatcher;
    }
}

The Build method creates a new thread with a WPF Dispatcher and correct synchronization context on it. This thread runs until you shut down the dispatcher. You could then use eg Dispatcher.BeginInvoke to create your hook.