System.Windows.Controls.Button

[webus]

Hi,

I've created a button in chart trader (System.Windows.Controls.Button). Everything works OK, but I've decided to add a new feature. I want to change the Button's Context and Background as soon as a signal is triggered in OnBarUpdate.
The code is:

            public void SetSignal(SignalType val){
                if (trSignalType != val){
                    trSignalType = val;

                    Application.Current.Dispatcher.Invoke(() =>
                    {
                        switch (trSignalType) {

                            case BUY:
                                trButEntry.Background     = Brushes.Olive;
                                trButEntry.Content         = "Long";
                                break;

                            case SELL:
                                trButEntry.Background     = Brushes.Red;
                                trButEntry.Content         = "Short";
                                break;

                            case NO:
                                trButEntry.Background     = Brushes.Gray;
                                trButEntry.Content         = "Is Disabled";
                                break;
                        }
                    });
                }
            }
​

However, as soon as a signal is triggered - the Strategy is disabled an I see this error:

 (OnBarUpdate:332) System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it.
   at System.Windows.Threading.Dispatcher.VerifyAccess()
   at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value)
   at NinjaTrader.NinjaScript.Strategies.Strategy1v1v0.Panel_ChartTrader.<SetSignal>b__29()
   at System.Windows.Threading.DispatcherOperation.InvokeDelegateCore()
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Windows.Threading.DispatcherOperation.Wait(TimeSpan timeout)
   at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherOperation operation, CancellationToken cancellationToken, TimeSpan timeout)
   at System.Windows.Threading.Dispatcher.Invoke(Action callback, DispatcherPriority priority, CancellationToken cancellationToken, TimeSpan timeout)
   at System.Windows.Threading.Dispatcher.Invoke(Action callback)
   at NinjaTrader.NinjaScript.Strategies.Strategy1v1v0.Panel_ChartTrader.SetSignal(SignalType val)
   at NinjaTrader.NinjaScript.Strategies.Strategy1v1v0.ActionEntry()
   at NinjaTrader.NinjaScript.Strategies.Strategy1v1v0.OnBarUpdate()​

How can I solve the issue?

[NinjaTrader_ChelseaB]

Hello webus,

Use the dispatcher from ChartControl (the UI thread).

ChartControl.Dispatcher.InvokeAsync()