angular.js - How to use angular to implement three-level linkage of an array

Question

The array looks like this. I want to use Angular to realize the three-level linkage of provinces and cities. The current code looks like this, and the result cannot be realized. Can't get city

phpcn_u1582 · Answer

It’s useless for you to write like this

ringa_lee · Answer

I asked a very stupid question = =Using ng-change to change the state according to the previous level can achieve three-level linkage