App in Mac constantly claiming focus

[gainasp]

I am have compiled a application in my mac which runs fine in windows (mingw) and in linux. But in my mac, once I execute the app, I cannot switch to another application, or move to another desktop (space). Every time I try to do so, the app gets again the focus (if I move to another desktop, it immediately comes back to the desktop where the app is, and it gets the focus).

I have checked in the activity monitor that it is not consuming resources in some kind of loop, and as I mentioned, it is working fine in other platforms. The Qt examples run fine, so it must be something related to this app. Any ideas of what the problem can be in the mac platform?

I am using:
Qt 4.8.3
Qwt 6.0.1
Mac OSX Mountain Lion (10.8.3)

Any help would be really appreciated. I am desperate after several hours of frustration. I have not found any thing remotely similar to this by googling...

Thank you,

Raúl.

Added after 45 minutes:

Well, it was coming to here, and finding the solution. This behaviour was due to improperly using a timer in combination with a splash screen. It is strange bacause in the other platforms it was working fine. But anyway, I have changed it in a way which works on the mac, and should also work in other platforms too.