安装fcitx-frontend-qt5
azheng@ubuntu16:~$ sudo apt-get install fcitx-frontend-qt5
拷贝plugin文件到Qt对应的目录中
azheng@ubuntu16:~$ cp /usr/lib/x86_64-linux-gnu/qt5/plugins/platforminputcontexts/libfcitxplatforminputcontextplugin.so /home/azheng/Qt5.7.0/5.7/gcc_64/plugins/platforminputcontexts/azheng@ubuntu16:~$ cp /usr/lib/x86_64-linux-gnu/qt5/plugins/platforminputcontexts/libfcitxplatforminputcontextplugin.so /home/azheng/Qt5.7.0/Tools/QtCreator/lib/Qt/plugins/platforminputcontexts/
azheng@ubuntu16:~$
重启Qt5， 测试OK。