angularjs - My $scope variable not updated -

i have collection of objects service:

$scope.rooms = testdata.list().rooms;  // {"room1":{"name":"bathroom"},"room2":{"name":"wcc"},"room3":{"name":"kitchen"}}; 

i need find room $routeparams.id

$scope.room = $scope.rooms[$routeparams.id];  // example $routeparams.id = 'room1' 

if inspect in view:

{{rooms}}  {{room}} 

i see how rooms dynamically updated, room undefined. if call in view this:

{{room = rooms[roomuid]}}  // $scope.roomuid = $routeparams.id 

it found room expected. why can not find room in controller?

updated:

i found problem, $scope.rooms collection empty when try find room id. $timeout $scope.room work expected, how start finding room after $scope.rooms populated?

$timeout(function(){$scope.room = $scope.rooms[$routeparams.id];}, 3000); 

i solved by:

if($routeparams.id){   $scope.action = 'edit';   $scope.roomid = $routeparams.id;   $scope.$watch('rooms.' + $scope.roomid, function(){     $scope.room = $scope.rooms[$routeparams.id];           }); }; 

it good?

$scope.$watch not required in case. 1 add $watch if room dynamically added , @ time want something.

just check $routeparams.id , if it's not undefined start searching room.

in case you're fetching rooms data service. put logic getting particular room inside then resolve function. in way sure rooms list available before search particular room.