Sorting nested JSON-data containing @attributes with AngularJS

Using the array.map you could project your data so that it is easier to work with and get rid of the @attributes property:

var app = angular.module('app', []);

app.controller('MainCtrl', function($scope) {
  $scope.orderByField = 'population';
  $scope.reverseSort = false;

  var data = {"states":{
      "state":[{
        "@attributes":{ "name":"ALABAMA","abbreviation":"AL","capital":"Montgomery","most-populous-city":"Birmingham","population":"4708708","square-miles":"52423","time-zone-1":"CST (UTC-6)","time-zone-2":"EST (UTC-5)","dst":"YES"}},{
        "@attributes":{"name":"ALASKA","abbreviation":"AK","capital":"Juneau","most-populous-city":"Anchorage","population":"698473","square-miles":"656425","time-zone-1":"AKST (UTC-09)","time-zone-2":"HST (UTC-10)","dst":"YES"}}]}};

  data.states.state = data.states.state.map(function(value) {
    return value['@attributes'];
  });

  // at this stage the data variable will look like this:
  //{
  //    "states": {
  //        "state": [
  //            {
  //                "name": "ALABAMA",
  //                "abbreviation": "AL",
  //                "capital": "Montgomery",
  //                "most-populous-city": "Birmingham",
  //                "population": "4708708",
  //                "square-miles": "52423",
  //                "time-zone-1": "CST (UTC-6)",
  //                "time-zone-2": "EST (UTC-5)",
  //                "dst": "YES"
  //            },
  //            {
  //                "name": "ALASKA",
  //                "abbreviation": "AK",
  //                "capital": "Juneau",
  //                "most-populous-city": "Anchorage",
  //                "population": "698473",
  //                "square-miles": "656425",
  //                "time-zone-1": "AKST (UTC-09)",
  //                "time-zone-2": "HST (UTC-10)",
  //                "dst": "YES"
  //            }
  //        ]
  //    }
  //}

  $scope.data = data;
});

Now in your view you could simply use that:

<tr ng-repeat="state in data.states.state|orderBy:orderByField:reverseSort">