Step 1: Adding a Graph Action

In this step, you will create an extension of a graph of the Invoices (SO303000) form. In the extension, you will add an action that opens a repair work order. Do the following:

Learn the name of the graph where the action should be added:
1. On the Invoices form, click Ctrl + Alt, and click the Summary area of the form.
2. In the Element Properties dialog box, notice the name in the Business Logic box: SOInvoiceEntry.
In the PhoneRepairShop_Code project, create an extension of the SOInvoiceEntry graph, as the following code shows.
```
namespace PhoneRepairShop
{
    public class SOInvoiceEntry_Extension : PXGraphExtension<SOInvoiceEntry>
    {
    }
}
```
Tip: Use Acuminator to suppress the PX1016 error in a comment. In this activity, for simplicity, the extension is always active.

In the graph extension, implement the viewOrder action, as the following code shows.

        public PXAction<ARInvoice> ViewOrder;
        [PXButton, PXUIField(DisplayName = "View Repair Work Order")]
        protected virtual IEnumerable viewOrder(PXAdapter adapter)
        {
            var orderEntry = PXGraph.CreateInstance<RSSVWorkOrderEntry>();
            var order = orderEntry.WorkOrders.Search<RSSVWorkOrder.invoiceNbr>(
                Base.Document.Current.RefNbr);
            if (order == null)
                return adapter.Get();

            orderEntry.WorkOrders.Current = order;
            throw new PXRedirectRequiredException(orderEntry, true,
                nameof(ViewOrder))
            {
                Mode = PXBaseRedirectException.WindowMode.NewWindow
            };
        }

Add the following using directives.

using PX.Data;
using PX.Objects.AR;
using System.Collections;
using PX.Objects.SO;

Save your changes.