Object reference not set to an instance of an object (multi-time frame On Render)

[Impeesa]

Hello

I have written an indicator with several series and it works ok with these lines in OBU:

if (CurrentBars[0] < 1
|| CurrentBars[1] < 1
|| CurrentBars[2] < 1
|| CurrentBars[3] < 1)

return;

In order to get better performance and smart results, I want to draw to use onRender method.

What changes should I do over my previous only one-serie code to avoid "Object reference not set to an instance of an object"? Any help or example is apreciated.

Thanks in advanced

[NinjaTrader_ChrisL]

Hi Impeesa, thanks for writing in.

The reason for the exception needs to be known before seeking a resolution. Use Visual Studio debugging to find the line that is throwing this error:

https://ninjatrader.com/support/helpGuides/nt8/NT%20HelpGuide%20English.html?visual_studio_debugging.htm

Turn on debug mode through the editor, open the Visual Studio project and attach it to the NinjaTrader.exe process, then run the indicator to cause the exception and Visual Studio will then break at the line causing the exception.

Best regards,
-ChrisL

[Impeesa]

Hello Chris

Maybe there is an easy answer before debugging. The code attached draws DeltaPercentValue above or below a bar if is greater or lower to a predefined value called LimitPercDelta. It works ok.

All I want is to add a new data serie (for example Range = 40) and wait till this new data serie has two bar closed.

I just add lines highlighted as I have done before in an indicator using Draw method instead Sharp.DX.

//================================================== ============
else if (State == State.Configure)
{
AddVolumetric(null, BarsPeriodType.Tick, tickOne, VolumetricDeltaType.BidAsk, 1);
AddDataSeries(BarsPeriodType.Range, 40);
}

protected override void OnBarUpdate()
{
if (CurrentBars[0] <= BarsRequiredToPlot
|| CurrentBars[2] < 2)

return;

//================================================== ============

As a result, Message "Error on triggering custom event for NinjaScript `myRenderTest´on bar 26: Object reference not set to an instance of an object"

Obviously that is not the way to go. How should I add new data serie and wait till this new data serie has two bar closed?

Sincerely,

[NinjaTrader_ChrisL]

Hi Impeesa, thanks for your reply.

The error means an uninitialized (null) object is being accessed. If the issue were a barsAgo error we would get a specific message about it. You will need to use Visual Studio to know what line the exception occurs on. The OnRender method is using the High array so it can be either the primary or secondary series. If the script is now multiseries it will need to target a series e.g. Highs[0].GetValueAt. TriggerCustomEvent should also not be used in OnRender, just use GetValueAt to access a bar index.

Best regards,
-ChrisL

[Impeesa]

Hello Chris

Thanks a lot for your reply. I am a bit confused.

I tried to follow your advide in post #4 using TriggerCustomEvent and it does work ok, but maybe I did not in a right way...

In which method should have I use TriggerCustomEvent in that situation?

And why using a secondary data serie in new script attached is not advisable?

I am learning a lot in this forum with your team help and I appreciate your patience.

Sincerely,

[NinjaTrader_ChrisL]

Hi Impeesa, thanks for your reply.

TriggerCustomEvent is used to ensure all data points are up to date before executing a command. It can cause performance issues if you are doing this within OnRender. I do not see any script attached, could you upload again?

Best regards,
-ChrisL

[Impeesa]

Hello Chris

Script is attached in post #3, and now again.

Please, have a look at your reply #4 in topic "plotting delta values onrender".

Sincerely,

[NinjaTrader_ChrisL]

Hi Impeesa, thanks for your reply.

It's not that using multiple series is not advisable. The script's OnRender method is using High.GetValueAt so this can be referencing either the primary or secondary data series depending on the BarsInProgress context. If you want to target a specific price series use Highs[0].GetValueAt(0 or Highs[1].GetValueAt().

Best regards,
-ChrisL