Validator for ExtJS Checkbox
Very unfortunately ExtJS doesn’t offer a validator for its checkbox component. Normally a validator checks whether a field is valid and takes care of displaying an error message if not. For a checkbox we would like that to happen if the checkbox is not selected. Overriding the validate function of the checkbox we can provide such a functionality for all checkbox instances we are about to create: Ext.form.Checkbox.prototype.validate = function(){ if (this....