Enchancements for sales order header - VA01

Question

Hi,
Could any one suggest is it possisble to enhance the additional data tab B(Screen number 8309) of the sales order header like below mentioned.If its possisble please suggest the procedure.
I need to create a new field in the screen number 8309 of VA01 with drop down box, a possisble list of 7 entries to be provided and if cursor is placed on a value of the list a box(item Box) should be open with the list of possisble values again like this there will be 3 items box and finally the user should be able to select the field and save it.
For EX just like Go->header->Additional functions->Additional data B.
Regards,
Nagendra

Answer 1

Hi Nagendra,
First append the requisite custom field in the structure of VBAK (since the Additional Tab B is for Header data).
Go to screen number 0312 in program SAPMV45A and develop the screen layout along with the Custom Field of VBAK structure, as it is done in normal module pool programming.
Then in the PAI and PBO section of the screen define PAI and PBO modules or use the already defined modules.
Then double click on the module and create the modules in Inlcudes MV45AOZZ (PBO) and MV45AIZZ (PAI). Write your requisite code in the created PAI and PBO modules.
In case the screen field name does not match with the table field name (e.g., let us say that the custom field in table VBAK is "ZZCUSTOM" and the screen field is "CUSTOM1"), the field value from the structure/table (i.e., assign VBAK-ZZCUSTOM to the screen.) has to be assigned to the screen field (CUSTOM1) in the PBO module and in the PAI module the value from the screen field has to be assigned back to the structure/table field.
In PAI : VBAK-ZZCUSTOM = CUSTOM1.
IN PBO : CUSTOM1 = VBAK-ZZCUSTOM.
But if the screen field name is VBAK-ZZCUSTOM then the above assignments need not to be done. It will be handled by the system itself.
As for the list box, while defining the screen layout, define the field property as list box.
But I dont think that the second list of possible entries is not possible by using listbox.
Instead you can do define a normal F4 help for the 1st list of possible entries. Then when the user selects a entry you can call a modal screen (i.e., pop up screen) with the 2nd list of possible values. When a user selects a entry from this list you can put that value in the screen field.
Hope this helps.
Regards,
Abhisek.