JUCE "background only" App with TUIO


#1

Using JUCE with TUIO, I’m developing a multi-touch utility to send “hot keys” commands to other applications (I am using a usb touch frame that sends TUIO messages). For instance, I provide an interface through which users can touch-and-hold to program a key combo and then tap that button to send the programmed key combo to another app. They way I accomplish this on OSX is by running my utility as a “background only” application (NSApplicationActivationPolicyProhibited). I use [NSWindow setCanHide: NO] so the GUI of my utility is visible even though it runs as a background app.

It works well except in the case that a window from another application is on top of mine. What happens is that touches get passed through that other app into mine- causing unintentional button pushes in my app. Normally, I could have my app only listen to the TUIO touch callback whenever is is the active application, [NSApp isActive]. But, since my app is background only, it is never active and I have no way to tell if another window is covering it to prevent touches.

So, is there any way for a “background only” app to be able to tell if it is on top of all other windows? Or, is there a way from within my app to get a list of all Cocoa windows from other applications and be able to tell if they are appearing on top of my “background only” app?


#2

Not sure about that, you’d need to look through the OSX windowing APIs and see what functions are available. TBH I wouldn’t expect there’s any way to detect the windows of other processes, because allowing apps to do that could be a security issue.