Excessive state changes in OnStateChange?

[Phoenix2518]

Hello. I'm trying to create custom market analyzer columns, but I'm seeing very strange behavior with even simple scripts. Here is my test script:

namespace NinjaTrader.NinjaScript.MarketAnalyzerColumns
{
    public class TestColumn : MarketAnalyzerColumn
    {
        protected override void OnStateChange()
        {
            Print(State);
        }
    }
}

After this script is compiled, I go to New > Market Analyzer, then Add Instrument(s) > AAPL, and finally Columns > TestColumn. I only have this one row and four columns (including the default Ask price, Bid price, and Last price), yet the output window looks like this:

SetDefaults
Terminated
SetDefaults
SetDefaults
Terminated
SetDefaults
Configure
SetDefaults
SetDefaults
Terminated
Terminated
Terminated
Terminated
SetDefaults
Configure
DataLoaded
Historical
Transition
Realtime

I don't understand where all of this came from. Why are there so many SetDefaults states? Why are there two Configure states when the docs claim it's only supposed to be called once in the lifetime of the object? Why are there any Terminated states at all, let alone so many? This is not expected behavior at all.

[NinjaTrader_ChelseaB]

Hello Phoenix2518,

NinjaTrader must create instances of all scripts to display in the Columns window, and creates a new instance when one is added, and when its enabled.

Below is a public link to the help guide on NinjaScript Lifecycle.

https://ninjatrader.com/support/helpGuides/nt8/en-us/understanding_the_lifecycle_of.htm?zoom_highlightsub=lifecycle

Below is a public link to a forum post where Matthew has described the lifecycle of a NinjaScript using prints.

https://ninjatrader.com/support/forum/forum/historical-beta-archive/version-8-beta/85086-why-is-state-terminated-run-when-another-different-indicator-is-loaded?p=726288#post726288

[Phoenix2518]

I finally had time to review both pages after the holiday. According to the life cycle chart from the first link, we have:

1) SetDefaults > Terminated for all indicators, to build the list.
2) SetDefaults > Terminated when selecting an indicator to display its properties.
3) SetDefaults > Configure > [active/processing states] while the indicator is displayed in the Market Analyzer, followed by Terminated upon exiting.

Official documentation gives us a total of three SetDefaults, three Terminated, and one Configure. In stark contrast, my situation produces seven SetDefaults, six Terminated (seven upon exiting), and two Configure.

Just to be sure I didn't have any other classes interfering with my results, I added "this.GetType().ToString()" to the Print statement and tested again. Before each test, I close the Market Analyzer; only then do I clear the output window. Then I open a new Analyzer, add a single stock, and finally add my test column. The following output was produced:

NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Configure
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Terminated
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... SetDefaults
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Configure
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... DataLoaded
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Historical
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Transition
NinjaTrader.NinjaScript.MarketAnalyzerColumns.TestColumn ... Realtime

So the exact same, demonstrated to be from the one trivial class. The question now is, where are four SetDefaults, four Terminated, and one Configure coming from?

[NinjaTrader_ChelseaB]

Hello Phoenix2518,

Our Development has stated they are not wanting to provide the inner workings of how script instances are created / destroyed for the Market Analyzer.

I can mention there will be new instances created when the Columns window is opened, when an item is selected in the Available list, when the add button is clicked, when the OK button is clicked, and as the actual instance that will be run in the window is created. There may be other internal instances created.

They have asked if you have a specific use case where this is causing an issue you are not able to work around.

Are you finding that the instance that makes it to the DataLoaded state is not terminating correctly?