On submit, check the validity of all inputs in a workflow and set an appropriate flag/state somewhere. Process the form only if everything is valid; otherwise, show an alert.
Yes, there are ways to do this for the most part. None are perfect though so it may take a bit of creativity to provide a good UX in all scenarios.
Note - the main limitation I’ve come across is that if the user tries to submit invalid inputs that are part of workflows (e.g., a workflow that tries to store that data in the databse) then Bubble won’t run any workflows (including workflows that you might use to notify the user that there was a problem).
Do a search on the forum and you’ll find several posts about returning error messages, dealing with the particular challenge I mention above, etc. Or, check the posts I’ve made in the last couple weeks if you can’t easily find them with a search.
This will not work as validation is done before being able to execute workflow. “This input should not be empty” is the element option checked. So I can’t count with workflows to do any type of check.