I am encountering an issue in OutSystems Data Cloud (ODC) with the **DropdownTags** widget
When there is only 1 remaining selected option in the dropdown list and the user removes it (clearing the selection entirely), the OnChange event handler is not triggered.
Steps to Reproduce
1. Drag a `Dropdown` (or `DropdownTags`) widget onto the screen in ODC.
2. Attach a Client Action to the OnChange event of the widget.
3. On the UI, select multiple options (e.g., Option A, Option B).
4. Remove options one by one:
- Removing Option A -> `OnChange` fires as expected.
- When only Option B remains, click to remove Option B -> `OnChange` DOES NOT fire.
Expected Behavior
The OnChange event should fire every time an item is added or removed, including when the last remaining item is removed (transitioning the selection list from `Length = 1` to `Length = 0`).
Environment Details
- Platform: OutSystems Data Cloud (ODC)
- Component: OutSystems UI (Dropdown / DropdownTags)
Has anyone found a clean workaround or fix for this without resorting to custom JavaScript event listeners
Hi @Hoang Huynh,
I tried it on my side and added a breakpoint in the OnChange action, and it's working as expected when removing or adding an item.
If possible, could you share your OML or explain how you've implemented it? There might be a small detail that's missing or a difference in the implementation that's causing the issue.
Hi @Sherif El-Habibi
Thanks for taking the time to test this!
Interestingly, after re-testing it on my end today, the OnChange event is now triggering as expected when removing the last item, just as you described.
It might have been caused by a temporary browser caching issue, a minor race condition during my initial test, or an un-synced runtime asset. Since I’m currently unable to consistently reproduce the bug.
If the issue pops up again, I'll record a quick clip and share a sample OML here for further inspection. Thanks again for your support!
Glad to hear. Of course feel free to reach out if it happens again.