Dynamic ButtonGroup not updated

[jo47011]

Hi Michael,

I'm currently working on a RadioInterface(SupervisedClientInterface) which I can contribute once I have it running. I'm currently stuck w/ a dynamically changing ButtonGroup. I do not want to hardcode the different radio modes but want to assign them based on feedback from the radio as those differ for each radio type.

This one works (hardcoded), see top button group in screenshot below:

modes_group = ValueListButtonGroup(
    label="Mode:",
    values=[
        ("FM", "FM"),
        ("DAB", "DAB"),
        ("Internet radio", "Internet radio"),
    ],
).connect(mode_var)
radio_page.add_item(modes_group)

This one fails, triggered once the radio values are published:

@modes_var.trigger
@shc.handler()
async def rebuild_modes(mode_list, origin):
    my_group = ValueListButtonGroup(
        label="Mode:", values=[(x.label, x.label) for x in mode_list]
    ).connect(mode_var)
    radio_page.add_item(my_group)

The [(x.label, x.label) for x in mode_list] corresponds to
[('Internet radio', 'Internet radio'), ('Podcasts', 'Podcasts'), ('DAB', 'DAB'), ('FM', 'FM'), ('Bluetooth', 'Bluetooth'), ('CD', 'CD'), ('USB', 'USB'), ('AUX in', 'AUX in')] so it is a superset to above hardcoded values.

See the bottom button group w/ spinners never gets updated even if the above button group is changed either by clicking or by changing it on the radio:

[mhthies]

Hi @jo47011,

in general, SHC is not designed to allow dynamic creation or modification of connectable objects after the interfaces have been started (e.g. from within logic handlers as in your case). This includes adding elements to web pages.

I assume that the following code in the WebServer interface causes the specific behavior you are observing:

smarthomeconnect/shc/web/interface.py

Line 169 in 40fb62d

for connector in itertools.chain.from_iterable(page.get_connectors() for page in self._pages.values()):

The map of all WebUIConnector, required for dispatching messages from the Web client (including 'subscribe' commands to be notified about value changes), is only filled at startup of the interface. Thus, widgets added later, will not be functional.

[jo47011]

Hmmm, thank you for the clarification. I already thought so. Well for the radio modes (which never change) we could somehow make it configurable or cache it (thus would work the 2nd time onwards). But there is also the presets and some other features depending on the mode. E.g. when playing a disc you can play, stop, pause, forward, ... but not when playing FM Radio. In change you will have some Presets here, e.g. Preset 1 is SWR, Preset 2 is DLF, etc.

So I think, not only for this widget/interface we would need some kind of dynamic adjustment of the web interface. Is this something you have ever thought about? Do you think it is realistic and do you have some guidance on how you we could do it? Smallest approach could be if we could change the labels of some widgets and show/hide them based on some condition.

Thanks a lot in advance for your valuable feedback, Jochen 😉