build issue : Did not find supported Qt SDK

When I built rstudio by source in Archlinux, an error told me "Did not find supported Qt SDK". But I have already installed the Qt SDK 5.13.1.

[root@archlinux build]# qmake -v
QMake version 3.1
Using Qt version 5.13.1 in /usr/lib

The install command is :

cmake .. -DRSTUDIO_TARGET=Desktop -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr/local/Rstudio -DLIBR_HOME=/usr/local/R/3.6.1/lib64/R/ -DLIBR_INCLUDE_DIRS=/usr/local/R/3.6.1/lib64/R/include -DLIBR_LIBRARIES=/usr/local/R/3.6.1/lib64/R/lib -DLIBR_DOC_DIR=/usr/local/R/3.6.1/lib64/R/doc -DBOOST_ROOT=/usr

The error is :
CMake Error at src/cpp/desktop/CMakeLists.txt:102 (message):
Did not find supported Qt SDK

You can try setting QT_QMAKE_EXECUTABLE to the path to qmake in your Qt installation; e.g.

-DQT_QMAKE_EXECUTABLE=/path/to/qt/bin/qmake

See also: https://github.com/rstudio/rstudio/blob/b86bfdfd149a3c66dace1b0fe7684d795f1a286a/src/cpp/desktop/CMakeLists.txt#L22-L101

Thank you very much, its worked.
But how can I get these settings like '-DQT_QMAKE_EXECUTABLE' for someone not familiar QT SDK. Before I ask question, I read the INSTALL document and google it. But the INSTALL document describ few arguments DRSTUDIO_TARGET, DCMAKE_BUILD_TYPE, CMAKE_INSTALL_PREFIX etc.

Sorry, I don't quite understand your question.

Some of these are just CMake variables that RStudio uses, but that we haven't documented. It's possible (likely?) that we need to update our install documentation; however, our recommendation is normally that users build RStudio packages either using our Docker scripts:

Or by using the package build scripts directly: