Invoking "Choose Application" application launcher from native OS

[Santosh Reddy]

I don't think Qt supports this feature yet.
You can try using the native command line options i.e, run "RUNDLL32.EXE SHELL32.DLL,OpenAs_RunDLL <myfile.ext>" using QProcess, it should open a open with dialog

Edit: By the way did you try, bool QDesktopServices:: openUrl ( const QUrl & url );