Change event for the dropdown in Edit mode

columns: {
Affilliate: { title: 'Affiliate', editable: false },
Year: { title: 'Year', editable: false
Site: { title: 'Site' },
Ctry: {
title: 'Ctry',
editor: {
type: 'list',
config: {
list: this.countries,
},
}
},
St: {
title:'St',
editor: {
type: 'list',
config: {
list: this.states,
},
}
},
}

My code is like this. In edit mode, when a country is selected from the drop down, I need to update the drop down for states with the filtered values based on the selected country. Is there a change event on the drop down? How else can I accomplish this?