Barcode Scan States: To Create the Input State

This activity will walk you through the creation of the input scan state.

Story

Suppose that you are implementing a scan mode for a custom barcode-driven form. The barcode scan class of this form uses the WarehouseManagementSystem<TSelf,TGraph> base scan class.

For this scan mode, you need to define the input scan state, which handles the reference number of a document.

Process Overview

Because you need the input state to belong to a certain mode, you will nest the input state in the CountMode scan mode class.

The base barcode scan class already has a blank class for creating a state that handles the reference number of a document. Therefore, you can skip the implementation of particular properties and methods. You will not implement the following members:
  • Code: It will use the default implementation of WMSBase.RefNbrState<INPIHeader>, which is RNBR.
  • IsStateActive(): It will use the default implementation of the EntityState<TBasis, TEntity> class, which returns true.
  • IsStateSkippable(): It will use the default implementation of the WMSBase.RefNbrState<INPIHeader> class, which is "Basis.RefNbr != null && Basis.Header.ProcessingSucceeded != true".
  • SetNextState(): It will use the default implementation, which moves the system to the next state based on the transition map.

In the Validate() method, you will reuse the method introduced in Barcode Scan Class: To Create a Barcode Scan Class.

System Preparation

Before you begin performing the steps of this activity, do the following:

  1. Prepare an MYOB Acumatica instance by performing the Test Instance: To Deploy an Instance prerequisite activity.
  2. Create a barcode scan class by performing the Barcode Scan Class: To Create a Barcode Scan Class prerequisite activity.
  3. Create the scan mode and define its required properties by performing the Barcode Scan Mode: To Define the Required Properties prerequisite activity.
  4. Create the set of scan states by performing the Barcode Scan States: To Create the Set of Scan States prerequisite activity.

Step 1: Defining the Required Members

To create the input state, do the following:
  1. In the CountMode class, create the RefNbrState class, as follows. 
    public class INScanCount : WMSBase
{
    ...
    public sealed class CountMode : ScanMode
    {
        ...
  
        public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader> 
        {
            
        }
    }
}
  2. In the RefNbrState class, define the required StatePrompt member, as follows.
     public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader> 
 {
     protected override string StatePrompt => Msg.Prompt;

     [PXLocalizable]
     public abstract class Msg 
     {
         public const string Prompt = "Scan a reference number of the PI count.";
     }
}

Step 2: Implementing the Cycle-Processing Members

Implement the cycle-processing members of the state as follows:
  1. In the RefNbrState class, define how a barcode should be transformed into an entity it represents as follows.
    public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader>
{
    ...             
    protected override INPIHeader GetByBarcode(string barcode) => 
        INPIHeader.PK.Find(Basis, barcode);    
    ...
}
  2. Define the response that is displayed to a user if the state cannot find an entity, as follows.
    public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader>
{
    ...             
    protected override void ReportMissing(string barcode) => 
        Basis.ReportError(Msg.Missing, barcode);
    ...
    [PXLocalizable]
    public abstract class Msg 
    {
        ...
        public const string Missing = "The {0} PI count was not found.";
    }
}
  3. Provide the entity validation, as shown in the following code.
    public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader>
{
    ...             
    protected override Validation Validate(INPIHeader entity) => 
        Basis.IsDocumentStatusEditable(entity.Status) 
        ? Validation.Ok
        : Validation.Fail(Msg.InvalidStatus, 
            Basis.SightOf<INPIHeader.status>(entity));
    ...
    [PXLocalizable]
    public abstract class Msg 
    {
        ...
        public const string InvalidStatus = 
            "Document has the {0} status, cannot be used for count.";
    }
}
  4. Implement the Apply() and ClearState() methods as follows.
    public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader>
{
    ...             
    protected override void Apply(INPIHeader entity)
    {
        Basis.RefNbr = entity.PIID;
        Basis.SiteID = entity.SiteID;
        Basis.NoteID = entity.NoteID;
        Basis.DocumentView.Current = entity;
    }
    protected override void ClearState() 
    {
        Basis.RefNbr = null;
        Basis.SiteID = null;
        Basis.NoteID = null;
        Basis.DocumentView.Current = null;
    }
    ...
}
  5. Define the response that is displayed to the user if the entity was successfully found, validated, and applied to the state of the barcode-driven form, as follows.
    public sealed class RefNbrState : WMSBase.RefNbrState<INPIHeader>
{
    ...             
    protected override void ReportSuccess(INPIHeader entity) => 
        Basis.ReportInfo(Msg.Ready, entity.PIID); 
    ...
    [PXLocalizable]
    public abstract class Msg 
    {
        ...
        public const string Ready = 
            "The {0} PI count has been loaded and is ready for processing.";
    }
}