ReferencesStrategy

StrategyBaseConverter Class

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Definition

A custom TypeConverter class handling the designed behavior of a strategy’s property descriptor collection. Use this as a base class for any custom TypeConverter you are applying to a strategy class.

Notes:

Relevant base methods

MethodDescription
TypeConverter.GetProperties()When overriding GetProperties(), calling base.GetProperties() ensures that all default property grid behavior works as designed
TypeConverter.GetPropertiesSupported()In your custom converter class, you must override GetPropertiesSupported() and return a value of true in order for your custom type converter to work

Syntax

public class StrategyBaseConverter : TypeConverter

Failure to apply a type of StrategyBaseConverter on a strategy class can result in unpredictable behavior of the standard NinjaTrader WPF property grid.

Tip: Common strategy functions like Print() are not available to a type converter instance. To debug a type converter class, you can use the AddOn Debug Concepts or attach to a debugger (recommended)

Examples

// This namespace holds Strategies in this folder and is required. Do not change it.
namespace NinjaTrader.NinjaScript.Strategies
{
   // When applying the type converter, you must fully qualify the name
   [TypeConverter("NinjaTrader.NinjaScript.Strategies.MyCustomConveter")]
   public class MyCustomStrategy : Strategy
   {
     protected override void OnStateChange()
     {
         if (State == State.SetDefaults)
         {
           Name                             = "MyCustomStrategy";
         }
     }
     protected override void OnBarUpdate()
     {
         //Add your custom strategy logic here.
     }
   }
   // custom converter class for strategies
   public class MyCustomConveter : StrategyBaseConverter
   {
     // A general TypeConveter method used for converting types
     public override PropertyDescriptorCollection GetProperties(ITypeDescriptorContext context, object component, Attribute[] attrs)
     {
         // sometimes you may need the strategy instance which actually exists on the grid
         MyCustomStrategy strategy = component as MyCustomStrategy;
         // base.GetProperties ensures we have all the properties (and associated property grid editors)
         // NinjaTrader internal logic handles for a given strategy
         PropertyDescriptorCollection propertyDescriptorCollection = base.GetPropertiesSupported(context)
                 ? base.GetProperties(context, component, attrs) : TypeDescriptor.GetProperties(component, attrs);
         if (strategy == null || propertyDescriptorCollection == null)
           return propertyDescriptorCollection;
         // example of why you may need the instance that exists on the grid....
         if (strategy.EntryHandling == EntryHandling.UniqueEntries)
         {
           // do something in the event a property contains some value...
         }
         // Loop all of the properties of the strategy
         foreach (PropertyDescriptor property in propertyDescriptorCollection)
         {
           // do something with a specific property
           // cannot call **Print()** here
           // but you can call the static Output window "Process()"
           NinjaTrader.Code.Output.Process(property.Name, PrintTo.OutputTab1);
         }
         // must return the collection after making changes
         return propertyDescriptorCollection;
     }
     // Important:  This must return true otherwise the type converter will not be called
     public override bool GetPropertiesSupported(ITypeDescriptorContext context)
     { return true; }
   }
}