Distinguish in "State.Terminated" whether the indicator will be reloaded or removed

[rafaelcoisa]

Hey guys,
I'm designing some features for my indicator and I came across this question:
Is it possible to distinguish in "State.Terminated" whether the indicator will be reloaded or removed?
I want to do different things when the indicator is reloaded and when it is removed.

Thanks.

[NinjaTrader_Gaby]

Hello rafaelcoisa,

Thank you for your post.

Unfortunately no, State.Terminated is only called once when the object terminates (not reloads). You can specify in State.Terminated to do things like remove custom resources once the indicator is removed.

https://ninjatrader.com/support/helpGuides/nt8/onstatechange.htm

https://ninjatrader.com/support/helpGuides/nt8/understanding_the_lifecycle_of.htm

Please let us know if you have any further questions.

[rafaelcoisa]

Hey NinjaTrader_Gaby

By "reload" I mean all actions that trigger the "State.Terminated" but do not remove the indicator, such as changing the chart time-frame, changing the chart instrument, adding another indicator, reload ninjascript (F5 hotkey), etc.
Just to make sure the answer to my question is "no", I'll rephrase the question:
Is there a way to distinguish whether “State.Terminated” was triggered because the indicator will be removed or by some other action that triggers “State.Terminated”?

[NinjaTrader_Gaby]

Hello rafaelcoisa,

Thank you for your clarifying.

No, unfortunately I am not aware of any supported or documented way to detect why State.Terminated was triggered.

Please let me know if you have any further questions.

[rafaelcoisa]

NinjaTrader_Gaby

Another thing, when I add or remove an indicator, is this “add” or “remove” done in a collection?
I was thinking that if the "add" or "remove" happens on a collection and the "remove" happens before the "State.Terminated" trigger on my indicator, I could somehow detect if the indicator will be removed before that happens and thus put two different logics in "State.Terminated", one for removing and another for "reloading".

[NinjaTrader_Gaby]

Hello rafaelcoisa,

No, this is not done in a collection. I recommend reviewing the Help Guide page below on the NinjaScript Lifecycle to understand what happens when you are adding an indicator to a chart:

https://ninjatrader.com/support/helpGuides/nt8/understanding_the_lifecycle_of.htm

Please let me know if you have any further questions.

[rafaelcoisa]

NinjaTrader_Gaby

When I add an indicator to a chart, is there no collection involved?
I thought ChartControl had a collection for this. No?

[NinjaTrader_Gaby]

Hello,

Yes, there is a collection in the ChartControl however unless I am misunderstanding, you are trying to detect if the indicator has been removed from within that same indicator which wouldn't be possible. The "remove" happens when the script reaches State.Terminated - you wouldn't be able to detect a "remove" before reaching State.Terminated.

https://ninjatrader.com/support/helpGuides/nt8/chartcontrol_indicators.htm

Once the script has been removed because it has reached State.Terminated, then the collection would be updated since it would no longer be currently configured on the chart.

You could be able to keep track of currently configured indicators on a chart from a separate indicator from OnRender().

[rafaelcoisa]

NinjaTrader_Gaby

"to detect if the indicator has been removed from within that same indicator". Yes, that's what I was thinking about doing.
And, what about to "keep track of currently configured indicators on a chart from a separate indicator", is there an sample for that?
I know how to print the names of the currently configured indicators on a chart, but I still don't know how to keep track of them.

I saw how to do something similar with drawingtools here:

https://forum.ninjatrader.com/forum/ninjatrader-8/indicator-development/1188276-events-for-objects-drawn-on-the-chart

[NinjaTrader_Gaby]

Hello,

Please see the attached sample script using the chart control Indicators collection.

https://ninjatrader.com/support/helpGuides/nt8/chartcontrol_indicators.htm