Calling JavaScript from Streamlit/Python

Streamlit is Python framework, it helps to build UI with low code approach. Code runs on server and there is no functionality, which would allow to inject client side events with JavaScript. Luckily there is a 3rd-party Streamlit component, it allows to make JavaScript calls from server side Python code. Response from such JavaScript call is received within the same Streamlit execution, this makes it possible to use values returned from JavaScript in Python logic. In this example, I show one liner JavaScript call to get UI screen width, to be able to calculate layout structure adjustments in Python, based on the screen size.