Object reference not set to an instance of an object.

[DanielRMejia]

Hello,

I'm currently developing an indicator and when I load the indicator it only runs up to bar 4 but then I get this error: "Error on calling 'OnBarUpdate' method on bar 4: Object reference not set to an instance of an object." By the way, it's calculating OnEachTick. Below is the code I'm writing:

public class Prueba : Indicator
    {      
        private Series<List<double>> listPrices;
    }​

else if (State == State.Configure)
            {
                ClearOutputWindow();
                AddVolumetric(null, BarsArray[0].BarsPeriod.BarsPeriodType, BarsArray[0].BarsPeriod.Value, VolumetricDeltaType.BidAsk, 1);
            }
            else if (State == State.DataLoaded)
            {
                listPrices        = new Series<List<double>> (this, MaximumBarsLookBack.Infinite);​
            }

protected override void OnBarUpdate()
        {            
            if (BarsInProgress == 1)
            {
                if (Bars == null)
                return;
                
                NinjaTrader.NinjaScript.BarsTypes.VolumetricBarsType barsType = BarsArray[1].BarsType as
                    NinjaTrader.NinjaScript.BarsTypes.VolumetricBarsType;
                
                if (barsType == null)
                    return;
                
                double prices = Close[0];
                
                if(IsFirstTickOfBar)
                {
                    // create the list once per bar
                    listPrices[0] = new List<double>();
                }
                
                listPrices[0].Add(prices);
                
                foreach(double price in listPrices[0])
                {
                    Print("Current Bar: " + CurrentBar + "       " + price);
                }​

The same thing happens to me if I use a dictionary instead of a list.

Could you please help me with this problem?

[NinjaTrader_ChelseaB]

Hello DanielRMejia,

Using variables dynamically with AddDataSeries() methods, including AddVolumetric(), is not supported.

"Warning
Arguments supplied to AddVolumetric() should be hardcoded and NOT dependent on run-time variables which cannot be reliably obtained during State.Configure (e.g., Instrument, Bars, or user input). Attempting to add a data series dynamically is NOT guaranteed and therefore should be avoided. Trying to load bars dynamically may result in an error similar to: Unable to load bars series. Your NinjaScript may be trying to use an additional data series dynamically in an unsupported manner."

https://developer.ninjatrader.com/docs/desktop/addvolumetric

Using BarsArray[0].BarsPeriod.BarsPeriodType in AddVolumetric() is not supported and will break the Strategy Analyzer.


Your series listPrices is synchronized with the primary series and has bar updates with BarsInProgress 0.

You could choose to assign a new object in BarsInProgress 0.

You could choose to synchronize the series with the added series BarsArray[1].

listPrices = new Series<List<double>> (BarsArray[1], MaximumBarsLookBack.Infinite);

Further, you should check that the list is not null before attempting to call .Add().

if (listPrices != null && listPrices.Count > 1)
{
listPrices[0].Add(prices);
}
else
{
Print("{0} | BarsInProgress: {1}, listPrices is null or Count is 0", Time[0], BarsInProgress));
}

[DanielRMejia]

The code is working well with your solution.

Thank you Chelsea B. for your help.