I have a requirement to populate a custom page property dialog select options. And on selection of first dialog second should be populated. I have used datasource to populate the first dialog and on change have written an Ajax call and tried to filter the data and update the second datasource model class. But the problem is on change we are not able to call the datasource model class and hence the values for 2nd dropdown is not getting populated. Can anyone please tell me how to call a model on change of dialog field? Or any other idea how to implement it?