SM12 locks for screen programing

Hi,

I am displaying the list of entries in my ALV table ( project specific table entries).

On click opf one row, it will display the details in my screen programing.

I can edit a particular row and update the table. When I am in edit mode of a particular row then other user shoudnt use the same row.

This has to be handled as SM12 lock.

How to use enqueue or dequeue to do this...

Any help is appreciated.Thanks