I want to provide the source data for the front-end again in Python background according to the changes of front-end x_Range and y_Range.
At present, only one p.x_range.on_change or p.y_range.on_change can call background data rendering
Sorry, your question isn’t very clear-- can you provide a minimal working example of what you have now, and describe the behavior you want to see?
Update model data from the serve when figure.x_range and ffigure.y_range changes
There are only separate properties, that can be individually watched. There is not currently any “combined” range event.
plot.x_range.on_change('start', callback)
plot.x_range.on_change('end', callback)
plot.y_range.on_change('start', callback)
plot.y_range.on_change('end', callback)
Depending on your needs you may need to implement some form of throttling if you want to prevent the callback work from happening on all four events.