Display confirmation box: http://learnopenerp.blogspot.com/2017/12/how-to-display-confirmation-display-box.html

I know the confirmation box, but the point is that, my alert is depending on the response status from the server, which necessarily need to handle at the callback of the server calling functions.

Odoo have this feature too, when connection lost or saved a record with an invalid field. You can try it yourself, and the alert is on the top right corner of the page.

Therefore, I wonder, if it is possible to customize the function, such that it can also show successfully saved message by the similar format.