Calling an Indicator that contains a timer

[swcooke]

I am working with the Timer Example on this page. I've got it working in my script however, when I try to call my Indicator from a hosting Indicator the Timer seems to throw an error. I decided to try to call the TimerExample directly from a new Indicator and I get the same error. Here is the hosting Indicator that I am using to call the TimerExample:

namespace NinjaTrader.NinjaScript.Indicators{

    public class CallTimer : Indicator
    {
        TimerExample GUEST = null;
        protected override void OnStateChange()
        {
            if (State == State.SetDefaults)
            {
                Description                    = "Call Timer Test";
                Name                        = "CallTimer";
                IsOverlay                    = true;
                BarsRequiredToPlot            = 0;
                IsSuspendedWhileInactive    = true;
            }
            else if (State == State.DataLoaded)
            {
                GUEST = TimerExample(true,true,1500);
            }            
        }
    }
}

When I add this to a chart I get these errors:

Indicator 'CallTimer': Error on calling 'SetState' method: Object reference not set to an instance of an object.
Indicator 'TimerExample': Error on calling 'OnStateChange' method: Object reference not set to an instance of an object

[NinjaTrader_ChelseaB]

Hello swcooke,

The example I created uses the ChartControl and is intended to be applied directly to a chart. If the indicator is called from another indicator it is not added to a chart and does not have a ChartControl object.

I've updated the script to return if the ChartControl is null to ensure this does not cause an error (or function) when called from another indicator.


As a tip, to export a NinjaTrader 8 NinjaScript so this can be shared and imported by the recipient do the following:

1. Click Tools -> Export -> NinjaScript...
2. Click the 'add' link -> check the box(es) for the script(s) and reference(s) you want to include
3. Click the 'Export' button
4. Enter a unique name for the file in the value for 'File name:'
5. Choose a save location -> click Save
6. Click OK to clear the export location message

By default your exported file will be in the following location:

• (My) Documents/NinjaTrader 8/bin/Custom/ExportNinjaScript/<export_file_name.zip>

Below is a link to the help guide on Exporting NinjaScripts.

http://ninjatrader.com/support/helpGuides/nt8/en-us/export.htm

[swcooke]

Can you supply a link to the updated zip? Same location?

[NinjaTrader_ChelseaB]

Hello swcooke,

Certainly, below is a link to the post with the updated scripts.

https://ninjatrader.com/support/forum/forum/ninjatrader-8/indicator-development/95391-nt8-sometimes-runs-onstatechange-termination-during-onbarupdate?p=777185#post777185

[swcooke]

Thanks Chelsea, for the great support!