Form validation using client handler : why does input sequence order change the result?

Question

I recently suggested (in this post) a script that checks if the different fields of a form have an answer before allowing to submit and I did it using a client handler with

Answer 1

Couldn't see where to add a comment but I wanted to ask about the .addClickHandler(clihandler2); to the grid. This is accomplished by adding it at the end of the

grid.setText(0, 0, 'This is a ')  [rest of the code (.setText .setWidget etc) ].addClickHandler(cliHandler2);

Also, can you let me know what the uploadtracker is on the widget position 9,0?? I didn't see it noted original code posted, but see upload and uploadtracker noted in the grid.set(text & widgets) in the revised piece of code.