Unsolved How to print log during Qt programe Installation?

[toushi]

I am creating a Qt Installer project based on QtIFW example (startmenu) . I want to output some log through console.log() in controller.qs and installscript.qs respectively，but running installation through Qt Creator only gets output like below. Is there any wrong during using console.log?

11:06:11: Starting D:\sourcecode\build-install-Desktop_Qt_5_12_1_MSVC2017_32bit-Release\Installer.exe...
Cannot register file downloader for https protocol: QSslSocket::supportsSsl() returns false
11:06:29: D:/sourcecode/build-install-Desktop_Qt_5_12_1_MSVC2017_32bit-Release/Installer.exe exited with code 0