There are two ways to build JS bundle, please choose what you like
If you prefer to write your JS Code in a separate project, you will have to add the lvgljs-ui package, located at src/render/react.
You can run the following code to the install npm package, and can then use your own bundle tool like webpack to build the bundle.
npm install lvgljs-ui
Warning
The lvgljs-ui package on npm is currently out-of-date.
The recommended approach is to use relative-deps to use a local version from this git repository.
If you prefer write JS Code in lvgljs dir, the file ./build.js will help you make js bundle, after edit the entry and outfile, run the following script in lvgljs dir, it will use esbuild to build bundle, and you dont need to install npm package lvgljs-ui
npm run bundle