Adding to a Tab with a Custom Button and Popup

 Hi @rashmikamudalinayake10 ,

You can find the this logic under the below graph extension, if you are using 24 R1.

 PX.Objects.Extensions.AddItemLookup.AddItemLookupBaseExt<TGraph, TDocument, TItemInfo, TItemFilter> abstract graph extension. It is implemented by PX.Objects.SO.GraphExtensions.SOOrderEntryExt.SOOrderSiteStatusLookupExt for SOOrderEntry

For previous versions, there is an action button command you can easily find in Aspx file.

 <CustomItems>
     <px:PXToolBarButton Text="Add Items" Key="cmdASI">
         <AutoCallBack Command="AddInvBySite" Target="ds">
             <Behavior CommitChanges="True" PostData="Page" />
         </AutoCallBack>
     </px:PXToolBarButton>

And here is the source code for that action command.

public PXAction<SOOrder> addInvBySite;
    [PXUIField(DisplayName = "Add Items", MapEnableRights = PXCacheRights.Select, MapViewRights = PXCacheRights.Select)]
    [PXLookupButton]
    public virtual IEnumerable AddInvBySite(PXAdapter adapter)
    {
        if (sitestatus.AskExt((PXGraph g, string viewName) => sitestatusfilter.Cache.Clear()) == WebDialogResult.OK)
        {
            return AddInvSelBySite(adapter);
        }
        sitestatusfilter.Cache.Clear();
        sitestatus.Cache.Clear();
        return adapter.Get();
    }

Hope, it helps!