Yes, I solved it. I don't remember how I installed it but strangely my installation missed ONLY this qhelplink.h and QHelpLink. How strange!

@JKSH Yes now It's working Thank you so much!

@chenqichen please write in english or use the appropriate subforum for your language.

@noone Would this be of any help to you? https://forum.qt.io/topic/79730/no-build-step-for-android It seems this guy had the same problem and solved it with adding gradle. Usually that error has to do with missing ndk/sdk or the more likely ant/gradle. Try running the build or deploy on the command line and see if it gives you more information.

hi @cc672012 you may have several problems, but the first one is that you assigned a 32bit compiler to a 64bit Qt version. That will not work.

@jsulm It has no business with g++. g++ is installed, and even though not, I have clang++ still.