I'm using the latest prerelease of RxUI 8, but I think this would happen in prior versions.
I have defined this ReactiveCommand in my WPF application:
GetWebsiteCommand = ReactiveCommand.CreateFromTask(DownloadString);
private async Task<string> DownloadString()
{
using (var client = new WebClient())
{
return await client.DownloadStringTaskAsync("http://www.google.es");
}
}
When the command is executed, the following exception is thrown:
System.InvalidOperationException' at System.Reactive.Core.dll: The calling thread cannot access this object because a different thread owns it
Why is this happening? I'm not creating any new thread!
This is the Stack Trace:
System.InvalidOperationException' at System.Reactive.Core.dll: The calling thread cannot access this object because a different thread owns it
at System.Windows.Threading.Dispatcher.VerifyAccess()
at System.Windows.DependencyObject.GetValue(DependencyProperty dp)
at System.Windows.Controls.Primitives.ButtonBase.get_Command()
at System.Windows.Controls.Primitives.ButtonBase.UpdateCanExecute()
at System.Windows.Controls.Primitives.ButtonBase.OnCanExecuteChanged(Object sender, EventArgs e)
at System.Windows.Input.CanExecuteChangedEventManager.HandlerSink.OnCanExecuteChanged(Object sender, EventArgs e)
at ReactiveUI.ReactiveCommand.OnCanExecuteChanged()
at ReactiveUI.ReactiveCommand`2.<.ctor>b__9_5(Boolean _)
at System.Reactive.AnonymousSafeObserver`1.OnNext(T value)
at System.Reactive.Linq.ObservableImpl.RefCount`1._.OnNext(TSource value)
at System.Reactive.Subjects.FastImmediateObserver`1.EnsureActive(Int32 count)
at System.Reactive.Subjects.FastImmediateObserver`1.EnsureActive()
at System.Reactive.Subjects.ReplaySubject`1.ReplayBase.OnNext(T value)
at System.Reactive.Subjects.ReplaySubject`1.OnNext(T value)
at System.Reactive.Linq.ObservableImpl.AsObservable`1._.OnNext(TSource value)
at System.Reactive.Linq.ObservableImpl.DistinctUntilChanged`2._.OnNext(TSource value)
at System.Reactive.Linq.ObservableImpl.CombineLatest`3._.S.OnNext(TSecond value)
at System.Reactive.Linq.ObservableImpl.RefCount`1._.OnNext(TSource value)
at System.Reactive.Subjects.FastImmediateObserver`1.EnsureActive(Int32 count)
at System.Reactive.Subjects.FastImmediateObserver`1.EnsureActive()
at System.Reactive.Subjects.ReplaySubject`1.ReplayBase.OnNext(T value)
at System.Reactive.Subjects.ReplaySubject`1.OnNext(T value)
at System.Reactive.Linq.ObservableImpl.AsObservable`1._.OnNext(TSource value)
at System.Reactive.Linq.ObservableImpl.DistinctUntilChanged`2._.OnNext(TSource value)
at System.Reactive.Linq.ObservableImpl.Concat`1._.OnNext(TSource value)
at System.Reactive.Linq.ObservableImpl.Select`2._.OnNext(TSource value)
at System.Reactive.SafeObserver`1.OnNext(TSource value)
at System.Reactive.ScheduledObserver`1.Dispatch(ICancelable cancel)
at System.Reactive.Concurrency.Scheduler.<>c.<ScheduleLongRunning>b__72_0(Action`1 a, ICancelable c)
at System.Reactive.Concurrency.DefaultScheduler.LongRunning.<>c__DisplayClass1_0`1.<ScheduleLongRunning>b__0(Object arg)
at System.Reactive.Concurrency.ConcurrencyAbstractionLayerImpl.<>c__DisplayClass7_0.<StartThread>b__0()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()