Getting "Indicator 'VPA': Error on calling 'OnBarUpdate' method on bar 20 -

[Tradarr]

I added a few divergence plots, added my interpretations of bag holding and end of a rising market plots, it compiles ok and exports ok but I am getting errors when applying to charts : "Indicator 'VPA': Error on calling 'OnBarUpdate' method on bar 20: Object reference not set to an instance of an object". I am not a coder I had a freelancer add plots for use in Market Analyzer to VPA a couple of years ago and have been adding plots like he did. I was hoping you guys could check out the code now and expain how to fix the error if possible? The export is attached and the plots I added are listed below. Wanting to submit to User Share once error fixed .
Thanks

AddPlot(Brushes.Transparent, "demandTestBar_");
AddPlot(Brushes.Transparent, "demandTestInDownTrendBar_");
AddPlot(Brushes.Transparent, "successfulDemandTestBar_");
AddPlot(Brushes.Transparent, "RSIPosDvg_");
AddPlot(Brushes.Transparent, "RSINegDvg_");
AddPlot(Brushes.Transparent, "MACDPosDvg_");
AddPlot(Brushes.Transparent, "MACDNegDvg_");
AddPlot(Brushes.Transparent, "StochPosDvg_");
AddPlot(Brushes.Transparent, "StochNegDvg_");
AddPlot(Brushes.Transparent, "EndOfRisingMarket_");
AddPlot(Brushes.Transparent, "EndOfRisingMarketCondOne_");
AddPlot(Brushes.Transparent, "BagHolding_");
AddPlot(Brushes.Transparent, "BagHoldingConditionOne_");
AddPlot(Brushes.Transparent, "RangeIncrease_");
AddPlot(Brushes.Transparent, "RangeDecrease_");

[NinjaTrader_Jim]

Hello Tradarr,

Thanks for your post.

We will not be able to debug and correct the script for you, but we would be happy to advise on how you can take debugging steps to identify the problematic part of code and how to resolve the issue once it is identified.

1. The first step is reproducing the issue. It looks like you can easily reproduce the issue just by adding the indicator to the chart
2. The next step is to add debugging prints throughout the OnBarUpdate method, and any methods called from OnBarUpdate, so that when you reproduce the issue, you can identify the specific part of code that throws the error
3. After the part of code is identified it would then be examined to see how it would encounter that error. For example, "Object reference not set to an instance of an object" would mean an object on the line of code that throws the error is null when it is referenced. You could add conditions above the line of code to see which object is null. I.E: if (ThisObject == null) Print("ThisObject is null");
4. Once the specific object that is null is identified, a correction would then need to be devised. I.E:
   1. Is it ok for this object to be null and should the code skip the reference if the object is null? (You can check if (ThisObject != null) { } to make sure the object is not null when it is referenced.)
   2. Should the object not be null when the code references it? In this case, further debugging steps would need to be taken to see when the object gets assigned to make sure it is assigned and not null when it should be.

Debugging Tips - https://ninjatrader.com/support/help...script_cod.htm

If the process is too difficult, you could consider enlisting the services of a NinjaScript Consultant to debug the script and make these changes for you.

Let us know if you have any questions.

[-=Edge=-]

"Indicator 'VPA': Error on calling 'OnBarUpdate' method on bar 20: Object reference not set to an instance of an object".

 demandTestBar = new Series<bool>(this); // is missing

[Tradarr]

 demandTestBar = new Series<bool>(this); // is missing

Thank You Very Much!

[8033075]

hi tradar! With the contribution here if you managed to correct the issue of the debugging and if you graph the divergences. Maybe you can share it to test it, I have been following the topic since I wanted to improve the layout of the original vpa.

[Ndakotan1313]

Tradarr I am having trouble installing the vpa v2, wondering if you have any ideas. Its saying it conflicts with something in my NT, even though there are very few things installed in NT.

Also, I went through Jim's code and fixed a formula and changed some symbols so they weren't doubled up. I'd be interested in discussing/collaborating on this with anyone on this.