Create own function to update state of Group

Setup, Configuration and Use Items & Sitemaps
1
  • Platform information:
    • Hardware: Raspberry pi
    • OS: openhabian
    • Java Runtime Environment: 11
    • openHAB version: 3.3.0
  • Issue of the topic:

I have several items for current temperature, humidity and target temperature.
I have the group gThermostat that includes all of the above.

In all UIs, the thermostat group shows with its label and a NULL. I guess that’s the state of the item, which is undef because I didn’t define an item type nor a function. I’d like to define the item-type of group gThermostat as String, and set its state as a sum-up of the children. The children are numbers. The function needs to get the value of each child and format them as a string, like “22C - T 25C - 45%”

In the documentation I see there is only a limited number of functions available. Can we create our own?
Alternatively, I tried creating a rule to update the group state whenever a child is updated. And that kind of works, but the state is reset to undef right away by, I think, the default EQUALITY function. Can I ‘disable’ this function for my group?

rule “gThermostat updater”
when
Member of gThermostat changed
then
gThermostat.postUpdate("")
end

2

Don’t think there is any way to do any of that. Just use an ordinary String Item.

3

I’d like to keep using a Group because the UI allows clicking on it to open/show the children

4

That’s easy to do with a regular Item in sitemap based UI.

Text item=myProxy {
   Text item=member1
   Switch item=member2
}

Clickable ordinary Item.

Should be possible in MainUI with a custom card, but I couldn’t tell you how.

5

One of the standard MainUI widget actions is to open a specified group popup.

For any page you should be able to use the gui editor to create a label card with whatever item you want as the label and then configure the card to show you the group popup of some different group item.

1 Like
6

I ended up creating my own list widget, which allowed me to customize the RHS text in the list and even add list-items from different groups. It wasn’t easy though. I wish there were more examples in the documentation. The custom widget system looks really powerful.