javascript - Angular custom method on $resource with .then() function causing error -

i have in angular service:

return $resource(base + '/cases/:id',     {id: '@id'}, {         status: {method: 'get', params: {status: '@status'}} }); 

when using method added $resource definition along promise's .then() function, i'm getting error:

cases.status({status: 'pending'})     .then(function(res) {         console.log(res);         $scope.cases.pending = res.data.cases;     })     .then(function() {         $scope.tabbed.pending = true;     }); 

after above snippet run, error is:

typeerror: undefined not function on line: .then(function(res) {

can not use these functions when i'm using method defined on $resource?

i think need use $promise of $resource object call success function when actual promise gets resolved & proceed promise chain.

code

cases.status({status: 'pending'}) .$promise .then(function(res) {     console.log(res);     $scope.cases.pending = res.data.cases; }) .then(function(cases) {     $scope.tabbed.pending = true; });