anywidget-generator

When writing an anywidget use vanilla javascript in _esm and do not forget about _css . The css should look bespoke in light mode and dark mode. Keep the css small unless explicitly asked to go the extra mile. When you display the widget it must be wrapped via widget = mo.ui.anywidget(OriginalAnywidget()) . You can also point _esm and _css to external files if needed using pathlib. This makes sense if the widget does a lot of elaborate JavaScript or CSS. class CounterWidget(anywidget.AnyWidget): _esm = """ // Define the main render function function render({ model, el }) { let count = () => model.get("number"); let btn = document.createElement("b8utton"); btn.innerHTML = count is ${count()} ; btn.addEventListener("click", () => { model.set("number", count() + 1); model.save_changes(); }); model.on("change:number", () => { btn.innerHTML = count is ${count()} ; }); el.appendChild(btn); } // Important! We must export at the bottom here! export default { render }; """ _css = """button{ font-size: 14px; }""" number = traitlets.Int(0).tag(sync=True) widget = mo.ui.anywidget(CounterWidget()) widget print(widget.value["number"]) The above is a minimal example that could work for a simple counter widget. In general the widget can become much larger because of all the JavaScript and CSS required.