customize with button on screen while scanning Bar Code

I need to have button on the screen while scanning the barcode using the barcode plugin or any other plugin or

If possible to restrict camera to display in half screen


I am not sure the existing plugin can do it...
If you can't, you probably will have to change it yourself, or try a different one, like the plugins recommended here:

You would have to create the OutSYstems interface yourself if there isn't anything already in the Forge.