I recently had a no start situation that was a key on = lights on, but no starter turnover situation. It was a malfunction of the handlebar stop/run kill switch. It was given a disassembly and cleaning to fix it up.
Checking the battery cables where they connect to the bike and not just the battery is advised, as is taking off the tank and checking the wiring connections all up around the ignition switch and head stem area.
Finally, how old is the battery? Might it be the culprit?
Best of luck to you.