Dispatcher.Invoke call now fails in 8.0.0.9

[GaryAlbers]

I have code that has been working for months in NT 8. It is in OnStateChange==Historical.
It calls 'Dispatcher.Invoke' to load a custom menu onto the Chart Window.
Now, when Dispatcher.Invoke is called, the chart appears to be forever loading, Ninja locks up and has to be killed. No matter how long I wait.

This issue is repeatable using the attached test indicator.
The indicator has a boolean parameter to turn the offending code on.
I also attached a recent trace file that verifies the ninja version.

I have been using 8.0.0.9 for a week or 2 but this problem only recently showed up.
I know the forced update was for a new certificate which seems far fetched to cause an issue, but something sure is different and broken.

If any coding rules have changed regarding when Dispatcher.Invoke can be called or from where, please advise.

Thanks,
Gary

[NinjaTrader_Jesse]

Hello,

Thank you for the question.

Due to changes with the last beta you are likely hitting a deadlock scenario using Invoke rather than BeginInvoke.

http://ninjatrader.com/support/helpGuides/nt8/en-us/multi-threading.htm?zoom_highlightsub=begininvoke

If you change the Invoke to BeginInvoke it should resume working as it was before.

I look forward to being of further assistance.

[GaryAlbers]

Thanks, problem solved

[ninZa]

Use Dispatcher.InvokeAsync() instead.
It's very quick to add "Async" to the name, and the problem is solved

As a best practice, you should always make sure to use Dispatcher.InvokeAsync() to ensure your action is done asynchronously to any internal NinjaTrader actions. Calling the synchronous Dispatcher.Invoke() method can potentially result in a deadlock scenarios as your script is loaded.

Ref: http://ninjatrader.com/support/helpG...-threading.htm