How to assign value to ng-model definition - angularjs

Question

I am using ui-bootstrap for typeahead in my application.
<input type="text" ng-model="newItem.id" class="form-control">
<pre>Model: {{customSelected | json}}</pre>
<input type="text" ng-model="customSelected" typeahead="asset as asset.asset_name for asset in assets | filter:{asset_name:$viewValue}" class="form-control">
When I select the autocompleted value, I can see my objects printed. But the problem is I am using newItem object to set form values and passing to $http requests, So how can I set customSelected.id to newItem.id ?
Getting error when I use something like this,
<input type="text" ng-model="newItem.id=customSelected.id" class="form-control">
Demo

Answer 1

If you want to assign the selected asset id to newItem.id:
<input type="text" ng-model="newItem.id" typeahead="asset.id as asset.asset_name for asset in assets | filter:{asset_name:$viewValue}" class="form-control">
UPDATE (FIDDLE)
View:
<div ng-app="App">
<div ng-controller="ctrl">
<input type="text" ng-model="newItem.id" class="form-control" />
<input
type="text"
ng-model="customSelected"
typeahead="asset as asset.asset_name for asset in assets | filter:{asset_name:$viewValue}"
class="form-control" />
</div>
</div>
Ctrl:
function ctrl($scope){
$scope.newItem = {};
$scope.assets = [
{
"id":"1",
"asset_reg_no":"AST1",
"asset_name":"Omega Shopping Complex"
},
{
"id":"2",
"asset_reg_no":"AST2",
"asset_name":"Keedam Chicken Farm"
}
];
$scope.$watch('customSelected', function(asset, oldAsset){
if(!asset && !oldAsset){
return;
}
if(oldAsset && !asset){
delete $scope.newItem.id;
delete $scope.newItem.asset_reg_no;
return;
}
$scope.newItem.id = asset.id;
$scope.newItem.asset_reg_no = asset.asset_reg_no;
});
}

Answer 2

If I understand you, this demo is what you want
function ctrl($scope){
$scope.assets = [{"id":"1","asset_reg_no":"AST1","asset_name":"Omega Shopping Complex","asset_type_id":"2","description":"Shopping Complex in Calicut","created_on":"2014-01-28 16:03:23","asset_type_name":"Building"},{"id":"2","asset_reg_no":"AST2","asset_name":"Keedam Chicken Farm","asset_type_id":"2","description":"Chicken farm in Valivida","created_on":"2014-01-28 16:04:06","asset_type_name":"Building"}];
$scope.newItem = {};
$scope.$watch('customSelected', function(asset, oldAsset){
$scope.newItem.id = asset.id;
$scope.newItem.text = asset.asset_name;
});
}