I have a web page with an autocomplete enabled combo textbox/dropdown. The user is able to enter values manually or pick a value from the list. While free text input is acceptable, I would like to visually warn the user that the data they have manually entered does not match a value in the list.
For reasons related to page layout I would like to avoid displaying anything on the page itself - the warning must be something that floats around. That being said, there are a few specific questions that I have:
- Where should the warning message appear? Above the textbox? Below?
- What should the warning message say? "The data you have entered does not match any listed values"?
- Should the warning message disappear on it's own after X seconds, or should the user have to click it?