is there a sample xojo web app that implement picture within the column of weblistbox?
You mean a picture that covers the column ?
For technical reasons, it is not very easy to do. In fact, a column in the DOM is composed of rows, and each is separate, containing all columns.
What I mean is that I want to put a button (ADD/MODIFY/DELETE) button within the column of weblistbox. So that It can be used for record maintenance.
Is it possible?
Sure, you can place the picture of a button using CellPicture and get the click with CellClick.