FileDownload Widget: How to handle the case of returning empty string/None?

[coderambling]

Did you see this question and code sample? Does that help? What exception message are you getting?

Button on_click callback never called

I am not sure why Button and its on_click do not trigger the defined callback in this MRE. import panel as pn ACCENT_COLOR = "#308752" pn.extension( sizing_mode="stretch_width", notifications=True ) class ButtonOnClick(pn.viewable.Viewer): def _download_callback(self): pn.state.notifications.success('_download_callback') def __init__(self): self.download_button = pn.widgets.Button(name="Download") self.download_button.on_click(self._downlo…