I have almost 4 months learning/working in SAP. I've done several reports and enhancements all along this time but recently I began to work in a requirement which is related to Mobile Data Entry or RF and it basically consists to add the EAN and some other data to the dynpro 2502.
I made a copy of the dynpro 2502 in program SAPLLMOB into SAPLXLRF 9502, related the user exit MWMRF502 and programmed the basic functionality of it but it is not working as I expected because this exit is very limited and it only lets me import and export a small group of data and is difficult to perform exactly as the standard.
I've been searching all over internet and a lot of people make their own implementations and other just simply change the standard. I don't know how to make my own implementation cause I don't understand all the process within and the alternative of changing the standard code would be better for performance and time spent in development but as I quoted I would have to change the standard code and that's something I would like to do only if there's no other option.
But the question is ¿Is it OK to change the standard? ¿How often is the the standard code changed in SAP implementations? ¿What would be the better alternative?
Thanks in advance.