beforeHide

fires before a Form control is hidden

boolean beforeHide(string name|id,any value){ ... };

name\|id	string	the name (or id, if the name is not specified) of the Form control
value	any	the current value of the control

boolean

false - to prevent a control from being hidden, otherwise true

form.events.on("BeforeHide", function(name, value) {
    console.log("BeforeHide", name, value); 
    return false;
});