There is an optional method within the UserJavaScript.js file named userJavaScriptAddBtn(). When this method is present you can return true or false to allow ExtraView to perform additional processing when the Submit button is pressed on the add screen. If this processing returns true, then the submit function continues, but if it returns false, then the submit is halted. Typically you will present the user with a message to indicate the error that you want them to correct.
The default code for the method within the UserJavaScript.js file is:
function userJavaScriptAddBtn() {
return true;
}
If the method is not present, no error is generated.