Error Messages and Developing for BloodHound

This page provides a list of some coding issues a 3rd party indicator may have, in turn causing errors with BloodHound or BlackBird.  NinjaTrader is forgiving when running an indicator on a chart, but is strict when running an indicator inside another indicator (i.e. using an indicator in BloodHound).

• Error Messages from BloodHound
• Developing for BloodHound
• Manual Removal & Fixing Developer Extension Errors
• Microsoft Visual Studio
• NinjaScript Indicator Tester

This error is benign. It is caused by a NinjaScript Add On that summons a list of objects and invokes those elements as a Visual object.

The NinjaAddons.ShortcutToolbar Add On is known to cause this error.

Example of offending code
VirtualizingStackPanel verticalStackPanel = null;
foreach (var v in chartGrid.Children)
     if ( v is VirtualizingStackPanel   &&
            // VirtualizingStackPanel is a Visual element
           (v as VirtualizingStackPanel).Uid == "ShortCutToolbar")
     {
          verticalStackPanel = v as VirtualizingStackPanel;
          break;
     }

BloodHound does not have any special requirements to be able to read/use other indicators, except for the MaximumBarsLookBack property as mentioned above.
The list below are common coding mistakes and bad practices that can cause errors.

Be sure to follow NinjaTrader's guild lines, Working with Brushes, when defining custom Brushes.  The primary concern is making sure custom Brushes are frozen to prevent threading errors, as NinjaTrader's documentation warns about many times.

Side note:  Brushes are not used by guest indicators, because they obviously can not draw on a chart, therefore BloodHound & BlackBird ignore Brushes properties.

Do Not modify Brush properties during State.SetDefaults or State.Configure.  Doing so causes threading issues for the hosting indicator/strategy (aka BloodHound / BlackBird).  Modify Brush properties during State.DataLoaded or afterwards.

Be sure to initialize Plots in accordance with NinjaTrader requirements.  We have seen many indicators initialize Plots in the wrong OnStateChange() state.
See documentation here, Indicator » AddPlot().

Follow the rules for setting plot values as outlined in the section Setting Values below.

BloodHound can read the following Series<T> types:  Bool, Int, Double, and Long.
A Series<T> can cause the following errors and other similar errors;

System.IndexOutOfRangeException:
System.ArgumentOutOfRangeException:
System.NullReferenceException:

When calling an indicator from another indicator (i.e. using an indicator inside BloodHound) strict NinjaScript protocols must be followed.  The following guidelines can eliminate those errors.

Initializing
All Series<T> must be initialize in the OnStateChanged() » State.DataLoaded section of your code, in accordance with Series<T> NinjaScript documentation.  Initializing anywhere else can cause errors when BloodHound tries to access the Series.

Synchronizing
Do not synchronize a Series<T> to a secondary Bars series.
E.G.  myData = new Series<double>(this, BarArray[1], MaximumBarsLookBack.Infinite);
Do not specify a BarsArray.  Allow the Series to sync to the primary Bars series.

Setting Values
BarsInProgress:  If the indicator uses multiple Bars series (multi-timeframes), only set values to the Series during BarsInProgress zero.  Setting values in any other Bars series can cause  System.ArgumentOutOfRangeException:  errors.

Example
protected override void OnBarUpdate()
{
  if(BarsInProgress == 0)
  {
               //  Set values during this Bars series
   mySeries[0] = Close[0];
  }
}

OnBarUpdate():  A public Series<T> must be set in OnBarUpdate().  Setting a public Series<> in other methods may create a synchronization issue.  Per NinjaTrader's best practices, BloodHound calls guest indicator data during the OnBarUpdate() event.  This is a timing issue with NinjaTrader's event driven methods.

OnMarketData():  A public Series<T> should not be set in this method.  BloodHound uses OnBarUpdate() to access indicator values.  Guest indicator that set a public Series<> in OnMarketData() return a null value.  Values gained from OnMarketData() should be stored and set to public Series<> in OnBarUpdate().

NinjaTrader does not call the OnRender() method when an indicator is called by another indicator, as is the case when using an indicator in BloodHound.  OnRender() is only called when the indicator is running on a chart.  Make sure no data is calculated in this method that is used for Plot values or Series<T> values.  Therefore, perform calculations for visual purposes only in this method.

ChartControl
This object is Null when an indicator is called by another indicator, as is the case when using an indicator in BloodHound.  Make sure ChartControl properties are not used or called when your indicator is running as a guest indicator.

Instrument
This object is Null during State.Configure.  Therefore, using the Instrument object directly in a AddDataSeries() will cause a Null reference.
e.g.  AddDataSeries( Instrument.FullName, _barsPeriodType, _Period);  will throw a Null error, because Instrument is still null during this State.

These instructions will remove the SharkIndicators software from NinjaTrader.  Those needing to remove Dev. Ext. pay attention to steps 5.1 and 6.

1. 1. Remove all custom NinjaScript code that references BloodHound.  Files such as 'TDU Bloodhound Statistics' or 'Smart TradeMarkers'.  All custom strategies and indicators that references or uses BloodHound must be removed/uninstalled from NinjaTrader first.
      1.  Protected indicators from 3rd party vendors can be removed by opening NinjaTrader Control Center » Tools menu » 'Remove NinjaScript Assembly'.
      2.  Open source custom indicators and/or strategies will need to be removed manually using 'Windows File Explorer'.
   2. Close NinjaTrader.
   3. Uninstall the SharkIndicators software.
      
      1.  Open the Windows Settings(Win 10) or  Windows Control Panel(Win 7).
      2.  Open ‘Apps’ (Win 10) or ‘Programs and Features’ (Win 7).
      3.  Locate and select SharkIndicator, then click Uninstall.
   4. Restart your computer.  This helps remove possible file locks, and has other benefits.
      (Do Not start NinjaTrader yet.)
   5. Open a 'File Explorer' window and navigate to ...\Documents\NinjaTrader 8\bin\Custom\ folder.  Delete any file that contain Sharkindicators, AWSSDK, Betwixt, Castle.Core, Jil, Ninject, PLUS, or Sigil in the file name.  Do Not delete files that have a .lic extension.
        (Click image to expand)
      
      1. Developer Extensions Note:  The SharkIndicators.BloodHound.cs and SharkIndicators.Common.cs files are for Dev. Ext.
      2.  Navigate to …\NinjaTrader 8\bin\Custom\Strategy\  folder.  If files exist, delete SiBloodHoundStrategyExample.cs and SiBloodHoundStrategyExample2.cs.  And, any other custom strategy that utilizes BloodHound.
   6. Skip this step if Developer Extensions are Not installed.  This step removes Dev. Ext. entries from the Config.xml file.  If you are fixing Dev. Ext. that were installed because you have a tool like TDU Bloodhound Statistics or Smart TradeMarkers, you may want to have their support person help you with this step. 
      Navigate your File Explorer to the  ...\Documents\NinjaTrader 8\ folder.
      1. Right-click on the Config.xml file, and Open with » Notepad.
      2. Look for the <References> section.  Then delete to two lines that list the SharkIndicators.???.dll.
         
   7. Restart NinjaTrader (without SharkIndicators software).
   8. Perform a NinjaScript compile test.
      1.  From the Control Center go to New » NinjaScript Editor.
      2.  In the editor window, Right-Click and then select Compile (F5).
   9. If the NinjaScript editor shows errors...
      1. As mentioned in step #5,  The files listed in this image can be deleted.
      2. If other files are listed, you can contact NinjaTrader support or the company the file came from.  They will help you resolve the error.
   10. If there are no errors, then close NinjaTrader, and reinstall SharkIndicators software again.

This is an indicator "wrapper" that creates the same environment as using an indicator in BloodHound.   This wrapper is intented to help indicator developers debug their indicators by visually seeing, on the chart, the data that BloodHound/BlackBird is receiving.  NinjaTrader is forgiving when running an indicator on a chart, but is very strict when running an indicator inside another indicator.
Instructions on how to use this wrapper are written within the code.  Open this indicator using the NinjaScript Editor to read.  Knowledge of NinjaScript programming is required.

Please Note:  SharkIndicators does not provide any type of programming help or support in any form.  If you need assistance, please contact a NinjaScript programmer, or the author of the indicator you are trying to test, or NinjaTrader support for general NinjaScript help.

Import into NinjaTrader 8 using the standard .zip file import process.
Click to download, IndicatorTesterForBloodHound_NT8.zip