- The code can be found in the grid-lecture branch of the class repository. It may be helpful that you examine the commit history to see how it was built.
- The documentation for SQLFORM.grid can be found here.
- The documentation for custom validators can be found here. BTW, the error in class is simply that I wrote onvalidate rather than onvalidation.
- In general, it would be useful if you read or skimmed the chapter of the web2py book on forms and validators.