Right click the package.json file, choose Show npm Scripts:

You will see :

Description of some scripts:

1. build : build all of the project, include resource and source. So preview the index.html or the index_debug.html will use the last code.
2. build-res : After add a new file or change the defined ids or styles, you should run this to let your js code can reference the change immediately.
3. build-ts2es6 : If you only change js code, you can run this script, so the index_debug.html will use the last code.
4. updateSDK : to update the AndroidUIX library.

Double click the script item will run it.