I am having 3 form fields in a window named as : studentId, StudentName, studentLastname. If I enter studentID, it should populate values of studentname and studentlastname. How can I do that? I know that, I have to use listeners, but I am not sure, how exactly I will load values from database for this. It should be AJAx request and not form submission/reload. 

Please let me know if u know it. I am using Extjs 4 and Spring MVC. 

Thanks.
Jm