Issue using bidir-value on a <select> when <option>s are added dynamically

[PokingUrsa]

We recently encountered an issue with Flavour when trying to specify a 'select' element with dynamically-generated options:

<select html:bidir-value="selectedValue">
  <std:foreach var="item" in="items">
    <option attr:value="item.value"><html:text value="item.description"></option>
  </std:foreach>
</select>

The tricky part is that "items" is being loaded from the server, and isn't available during the first template update.

What happens is:

• Pass 1
  • selectedValue is read, and bidir-value calls setValue on the select
  • items is empty, so there are no options in the select. setValue has no effect.
• Pass 2
  • selectedValue is read, but is the same as before. The call to setValue is skipped (line 56 of BidirectionalValueBinder)
  • items is now populated from the server call. option elements get added to the select, but the right one isn't selected (since setValue was not called again).

Is there a clean solution to this?

[cyberquarks]

@PokingUrsa have you tried std:if condition?

Not sure if all EL is documented by I just usually use sourcegraph to find some examples from the repo: https://sourcegraph.com/search?q=repo:%5Egithub%5C.com/konsoletyper/teavm-flavour%24+std:if&patternType=literal