Setting default item of select box using angularjs

Problem

I’m trying to set the default item of a select box on load using angularjs.

I load both select boxes from 2 json’s, so the second select box, named ‘city’ relies off the first select box ‘country’:

<label>Country:</label>
<select name="country" ng-model="form.country"
ng-options="c.n for c in countryList"
ng-change="countryChanged()" required></select>

<label>City:</label>
<select name="city" ng-model="form.city"
ng-options="c for c in cityList" required></select>

PLUNKER http://plnkr.co/edit/hKZLbMbwGfmaa8CtSy0H?p=preview

It loads the select boxes using $http.get. It loads all well and good if i default it to the first option. But lets say, I want to specify a certain option to be selected on load, but I can only send it a particular value from the json, how would I do this? In the code below, the commented line is what I've tried, but all it does is load the correct city list, but leave the country select box unselected.

countries.json

[
{"c":"au","n":"Australia","g":"1"},
{"c":"fr","n":"France","g":"2"},
{"c":"ge","n":"Germany","g":"2"}
]

Controller:

$http.get('countries.json')
.success(function (data) {
$scope.countryList = data;
$scope.form.country = data[0];
// $scope.form.country.c = 'fr'; <<<--- *trying to set default*
$scope.countryChanged();
});

$scope.countryChanged = function() {

$http.get($scope.form.country.c + '-cities.json')
.success(function (data) {
$scope.cityList = data;
$scope.form.city = data[0];
});
}

Also, if there is a better way to achieve this, please post it.

Note: I can’t join the json up. I split it because in the real world, there could be 100 countries each with 100 cities each and the json would be quite massive.

Problem courtesy of: jzm

Solution

Not sure, but does this satisfy the requirement? http://plnkr.co/edit/rBDVzg7iXfaHu4XmiVsb?p=preview

var selectCountry = function( data, code ) {
for ( var i = 0; i < data.length; i++ ) {
var country = data[ i ];
if ( country.c !== code ) { continue; }
return country
}
};

$http.get('countries.json')
.success(function (data) {
$scope.countryList = data;
$scope.form.country = selectCountry( data, 'fr');
$scope.countryChanged();
});

Solution courtesy of: Tosh

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