How do I populate and use Select contents as user types using Rest API

I have a simple select box where I'd like my app to call a Rest API as a user enters data (like a google search auto-suggest) and show the contents of the suggestions for the user to pick from.

I added an "Input value changed" event handler on it and it's successfully calling a Rest API and getting results, but the results aren't displaying on the screen.

The select's values are: {{ formatDataAsArray( => }}

The selects labels are: {{ formatDataAsArray( => }}

I haven't been able to figure out:

  1. How to get these matching results to display (the drop-down never populates with any matches to see). When I hover over in the Inspect browser for this item, I see the JSON array of 4 results and they all look accurate. But they don't show up on the user's screen.

  2. How to speed up the search so that, if the user types 4 characters, the UI doesn't wait for all 4 API calls to happen sequentially. In this scenario, it would be nice if the change event killed or ignored all API calls except the one triggered by the user's last key change

Then, once those values are shown on screen, the user can either select one (in which case the select box's 'value' attribute should be a numeric ID. When the user selects an item from the list, I want to use that numeric select field 'value' to trigger a follow-up Rest API call. But I only want to do that if the user select an item. If the user just leaves free-form text in the select field (yes, I enabled "Allow custom values"), then I don't want to trigger that follow-up query.

My app seems to ignore the condition and always sends the query. I added a "Change" event handler after the "Input value changed" one listed above and configured it to "Only run when" the following expression is true:

{{mySelect.value !=null && !isNaN(mySelect.value)}}

In a nutshell, if the user selected something from a list, it would have the primary key ID. If the user free-form entered text, then it would no need to do a follow-up query.

What's wrong with my event handler(s) and "Only run when" condition here?

I'm a newbie to Retool, so I'd greatly value and appreciate any help!


P.S. I don't intend to use a DB primary key in my public API :slight_smile: But this helps illustrate my distinction in this scenario for "OK to look up object from database based on user's selection" vs. "User is adding a new object".

Hey @mscongdon!

Happy to help here! Since each of these queries will as you said take time to run, I believe this logic is typically taken care of in the front-end if there is not an especially large number of results. About how many results are you filtering here? You could add a debounce to the event handler so that it only runs your query after some amount of time rather than on every change. Do you think this could work for your use case here?

As for triggering a query if a user makes a selection, this setup should work :thinking:, I tested something similar on my end and it seemed to only trigger when a change was made:

Are you seeing your query run on page load? If you are still blocked here would you mind writing into intercom chat so we can take a closer look at your app from our end?\