Resolve Error: “TypeError Cannot read property ‘setDisplayType’ of null” Returned by nlobjField.setDisplayType

Scenario

The user is getting the error: TypeError Cannot read property ‘setDisplayType’ of null when using the nlobj.setDisplayType method on a field pulled using the nlapiGetField API.

Solution

The nlapiGetField function is not supported for inline fields under any subtab on the Item record and executing it will return null. Thus, an error is received when trying to use the setDisplayType on a null object returned by the nlapiGetField API.