Unable to display sliders or plots render very slowly

Hello,

I have been experimenting with ipywidgets, and have run into very limited success. At first, I was able to properly run a widget with a single float slider, and it would perform perfectly and update real time. However, after copying the code over to another notebook, the slider disappeared and I only had a single frame/plot. Now even testing the basic code from the tutorial does not display sliders.

I am unsure if I properly installed everything, as I have to pip3 install ipywidgets, otherwise it stats that no module is found for ipywidgets. I am currently on version 7.2.1 for ipywidgets and 3.2.1 for widgetsnbextension.

When trying to debug this issue, I ran into ‘widget javascript not detected’, ‘jupyter widget could not be displayed because the widget state could not be found’, and now ‘ERROR | No such comm target registered: jupyter.widget.version’. After trial and error experimenting with various versions, I managed to have the sliders in working order again, but the plot would update extremely slowly, and collect a queue of events to process, even for very low computational plots.

Any help would be greatly appreciated, thanks!

[patrickrchao]

Thank you all so much for the suggestions! I think the continuous_update=False works okay, but I had mixed effects with the throttling and an error when trying to implementing the debouncing command, about lack of the function get_ioloop(), although it may just be on my end.

Is there any reason why the sliders maintain a queue of inputs? If I continuously move the slider back and forth very quickly, the updates will not keep up and continue through the queue of events slowly. To me this does not really make sense, as it would seem more intuititve to complete the most recent actions and update to the current state.

[hadim]

See a probably related issue here: https://github.com/InsightSoftwareConsortium/itk-jupyter-widgets/issues/114