I've got a possible client who has mocked up an application in FileMakerPro, shown it to me, and said "can you do this, but I want it to run on both Linux and Windows XP?" He wants this application to sell with hardware that he currently sells. The main page of the app basically has a normal form at the top with the result of one query (the "current job" information), then two tables with the results of other queries about the status of various components.
One thing he wants that he doesn't have in the mock up is the ability to respond to and generate external events - there is an external piece of equipment that closes a microswitch, and when that happens he wants to update one of the tables and update the results on the screen, and when certain updates happen on the database, he wants to turn on or off a warning light on the equipment. He also wants graphs of summaries of data from the database embedded on the screen (looking at the mock-up, I can't tell of the graphs he has are live or just static images he's put there to make it look like what he wants.) He's also concerned about security and put as a non-mandatory feature the ability to lock a copy to a particular machine.
I had a brief look at Kexi and Open Office Base, but I can't figure out if I can do even the basic main page functionality, never mind the graphs and the external events business. So I'm tempted to just quote him the price for me to develop a wxPython and MySQL app from scratch. Is there a better option? Can I do it with Base or Kexi?
(Also, suggestions on how to interface the external events would be appreciated. He wanted to just wire the microswitch into the F12 key on the keyboard and control the light by playing sounds through one channel to turn it on and one to turn it off, but that seems cheesy and cheap looking to me.)