Selection of items from `SelectMultiple` is broken after content update via observe.

My goal is to have two widgets, select and other that accept a list of options.

select may only take on one value, so I chose the RadioButtons widget for this. other may take on multiple values, so I used SelectMultiple. Further, the options available in other may not contain the value chosen in select. Ideally (but optionally), the selected items in other should be cleared when a new item is chosen from select.

I used widget.observe to update other when select changes, however (here’s the bug) the selection area in the SelectMultiple does not respond correctly to clicks after updates. For example, when I click one value, another becomes highlighted, or when I select a range an alternate set of values becomes selected. The behavior is erratic and inconsistent, so you might have to try a few times to get it to misbehave.

This code updates the content of other when the selection of select is altered:

from ipywidgets import SelectMultiple, RadioButtons, interact
options = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h']

select_widget = RadioButtons(options=options)
other_widget = SelectMultiple(options=sorted(list(set(select_widget.options).difference(set([select_widget.value])))),
                              selected_labels=())
other_widget.selected_labels = ()

def update_other(*args):

    other_widget.value = ()
    other_widget.selected_labels = ()
    other_widget.options = list(set(select_widget.options).difference(set([select_widget.value])))

select_widget.observe(update_other)

def printer(select, other):
    print(select, other)

interact(printer, select=select_widget, other=other_widget, __manual = True)

Thank you, Mike

[jasongrout]

I just tried both examples with current master (6.0.0b2 + some commits), and they seem to work fine.

I did notice another bug, which I fixed: #883.

[gnestor]

I can verify that it’s working on master. I’m closing. Re-open if you see this in the next release.