Open other page, but the caller page does not refresh completely

Hi All

NAV2013R2

I would like after user open "Warehouse Shipment" page, another page called "Scan Barcode" page open automatically for user start scanning the barcode.

The problem is the "Scan Barcode" page open before the whole "Warehouse Shipment" page is fully refreshed.

I tried to put my codes in "OnOpenPage, OnFindRecord, OnAfterRecord, OnAfterGetCurrRecord", but that does not help.

Could someone give me any suggestions.

Thanks