Set up the HarmonyOS SDK

1. Go to Preferences > SDKs > HarmonyOS.
2. In HarmonyOS SDK location, enter the directory that has the sdk and bin directories in it, or select Auto-detect to look for one in the usual places. The label below the field says what was found.
3. In Additional packages, enter the installation prefix of the third-party libraries built for HarmonyOS, which is the directory their lib is in. Qt Creator passes it to the build as QT_ADDITIONAL_PACKAGES_PREFIX_PATH, which adds the libraries into the package. Without them, the application installs and starts but cannot load the platform plugin.
4. Keep Create kits automatically selected to have Qt Creator offer a kit for every Qt for HarmonyOS it knows about.

Once the SDK location is set, the compilers in it appear in Preferences > Kits > Compilers, and a device that hdc reports appears in Preferences > Devices > Devices, without any further configuration.