How do I access a custom field from a PXSelector in another field?

@ppowell Your sintax looks good to me, is there any error you are getting?
In a BQL statement, like the one used in a PXSelectorAttribute, a custom field is accessed by referencing the DAC extension as you did.

What release of Acumatica are you targeting?

If you are only adding a condition based on fields from the same DAC in the selector (or extensions for those DACs) you can use the PXRestrictor attribute.

Here is an article with more information.

To add it without replacing existing attributes you use the PXMergeAttributes attribute.

Here is an article with more information.

Finally, I imagine you plan to add the constant and the CacheAttached method to every Graph extension where you need to use the filter, so you would use it in a graph that allows you to pick attributes, like the CustomerMaint graph and not the CSAttributeMaint graph.

I also switched your attribType definition with the new way to declare constant values:

namespace PX.Objects.CS
{

  [PXLocalizable()]
  public static class CustomMessages
  {
		public const string AttributeNotFound = "Attribute not found with required type";
  }

  // Use a graph that requires you to pick an attribute, not the CSAttributeMaint graph.
  public class CSAttributeMaint_Extension : PXGraphExtension<CSAttributeMaint>
  {
    #region Event Handlers

    // Switched to updated recommended class, other format is deprecated
	public class attribType : PX.Data.BQL.BqlString.Constant<attribType>
	{
		public attribType() : base("I") { }
	}

    // MergeAttributes keeps original attributes and let's us add new ones
    // PXRestrictor adds condition to existing PXSelector, but requires an error message
    //   for cases where value does not meet the condition.
	[PXMergeAttributes(Method = MergeMethod.Merge)]
	[PXRestrictor(typeof(Where<CSAttribute.attributeID, NotEqual<MatrixAttributeSelectorAttribute.dummyAttributeName>,
								And<CSAttributeExt.usrAttributeType, Equal<attribType>>>), CustomMessages.AttributeNotFound)]
	protected virtual void CSAttribute_AttributeID_CacheAttached(PXCache cache){}

    #endregion
  }
}

@Dioris Aguilar Sorry.  I don’t think I explained very well.  Instead of the constant I have defined I wanted to refer to the current value of the combobox on the screen so the PXSelector for Attribute ID would only list IDs that match the usrAttributeType.  I guess it would be in the cache somewhere but I’m not sure how to access it.

Thanks,

Phil

@Marco Villasenor Thanks for the detailed description. I’ll have a read of that and see what I can come up with..

Phil