I'm migrating my Angular 1.x code to use the newer, more preferred syntax of avoiding using $scope and using the controller as syntax. I'm having an issue with getting data from a service though.
Here's my example:
var myApp = angular.module('myApp', []);
myApp.controller('MainCtrl', ['$http', '$location', 'userService',
function($http, $location, userService) {
this.name = 'John Doe';
// this.userData = {
// }
this.userData = userService.async().then(function(d) {
return d;
});
console.log(this.userData);
}
]);
myApp.service('userService', function($http) {
var userService = {
async: function() {
// $http returns a promise, which has a then function, which also returns a promise
var promise = $http.get('https://jsonplaceholder.typicode.com/users').then(function(response) {
// The then function here is an opportunity to modify the response
// console.log(response);
// The return value gets picked up by the then in the controller.
return response.data;
});
// Return the promise to the controller
return promise;
}
};
return userService;
});
<body ng-app="myApp">
<div id="ctrl-as-exmpl" ng-controller="MainCtrl as mainctrl">
<h1>Phone Numbers for {{mainctrl.name}}</h1>
<button ng-click="">newest</button>
<p>{{mainctrl.userData}}</p>
<ul>
<li ng-repeat="users in mainctrl.userData">{{users.phone}} -- {{users.email}}</li>
</ul>
</div>
</body>
This issue I'm having is that the data returned from the userService.async is an object that I can't seem to drill down thru to get the data from, as the data is a child of $$state, which can't seem to be used in the view.
If this isn't the proper way to use services in the Controller As/$scope-less syntax, what is the proper way?
Live example here: http://plnkr.co/edit/ejHReaAIvVzlSExL5Elw?p=preview
You have a missed an important part of promises - when you return a value from a promise, you return a new promise that will resolve to this value.
The current way to set the data returned from a promise to a local variable in your controller is this:
myApp.controller('MainCtrl', ['$http', '$location', 'userService',
function($http, $location, userService) {
this.name = 'John Doe';
userService.async().then(function(d) {
this.userData = d;
});
}
]);
But now you are in a catch because of the scope of this, so it is common to use a "placeholder" variable for the controller this scope.
myApp.controller('MainCtrl', ['$http', '$location', 'userService',
function($http, $location, userService) {
var $ctrl = this; // Use $ctrl instead of this when you want to address the controller instance
$ctrl.name = 'John Doe';
userService.async().then(function(d) {
$ctrl.userData = d;
});
}
]);
this.userData = userService.async().then(function(d) {
return d;
});
In this bit of code this.userData is actually being defined as a promise. If you want the data that is being returned, you need to use the d parameter from your .then function like so:
userService.async().then(function(d){
this.userData = d;
//a console.log() here would determine if you are getting the data you want.
});
Edit
I just noticed in your Service that you are already using .data on your response object.
Honestly, my best advice to you would be to just return the promise from the http.get() call inside of your service like this:
myApp.service('userService', function($http) {
var userService = {
async: function() {
return $http.get('https://jsonplaceholder.typicode.com/users');
}
};
return userService;
});
And then you could use something like this to capture and utilize the response data:
userService.async().then(function(response){
this.userData = response.data;
);
This may be a bit cleaner of a solution
Related
I'm trying to count the items in an array without using ng-repeat (I don't really need it, i just want to print out the sum).
This is what I've done so far: http://codepen.io/nickimola/pen/zqwOMN?editors=1010
HTML:
<body ng-app="myApp" ng-controller="myCtrl">
<h1>Test</h1>
<div ng-cloak>{{totalErrors()}}</div>
</body>
Javascript:
angular.module('myApp', []).controller('myCtrl', ['$scope', '$timeout', function($scope) {
$scope.tiles= {
'data':[
{'issues':[
{'name':'Test','errors':[
{'id':1,'level':2},
{'id':3,'level':1},
{'id':5,'level':1},
{'id':5,'level':1}
]},
{'name':'Test','errors':[
{'id':1,'level':2,'details':{}},
{'id':5,'level':1}
]}
]}
]}
$scope.totalErrors = function() {
if ($scope.tiles){
var topLevel = $scope.tiles.data
console.log (topLevel);
return topLevel[0].issues.map(function(o) {
return o.errors.length
})
.reduce(function (prev, curr){
return prev + curr
})
}
}
}]);
This code works on codepen, but on my app I get this error:
Cannot read property '0' of undefined
and if I debug it, topLevel is undefined when the functions is called.
I think it is related to the loading of the data, as on my app I have a service that looks like this:
angular.module('services', ['ngResource']).factory('tilesData', [
'$http', '$stateParams', function($http, $stateParams) {
var tilesData;
tilesData = function(myData) {
if (myData) {
return this.setData(myData);
}
};
tilesData.prototype = {
setData: function(myData) {
return angular.extend(this, myData);
},
load: function(id) {
var scope;
scope = this;
return $http.get('default-system.json').success(function(myData) {
return scope.setData(myData.data);
}).error(function(err) {
return console.error(err);
});
}
};
return tilesData;
}
]);
and I load the data like this in my controller:
angular.module('myController', ['services', 'ionic']).controller('uiSettings', [
'$scope', '$ionicPopup', '$ionicModal', 'tilesData', function($scope, $ionicPopup, $ionicModal, tilesData) {
$scope.tiles = new tilesData();
$scope.tiles.load();
$scope.totalErrors = function() {
debugger;
var topLevel;
topLevel = $scope.tiles.data;
console.log(topLevel);
return topLevel[0].issues.map(function(o) {
return o.errors.length;
}).reduce(function(prev, curr) {
return prev + curr;
});
};
}
]);
but I don't know what to do to solve this issue. Any help will be really appreciated. Thanks a lot
The $http.get() method is asynchronous, so you can handle this in your controller with a callback or a promise. I have an example using a promise here.
I've made an example pen that passes back the sample data you use above asynchronously.This mocks the $http.get call you make.
I have handled the async call in the controller in a slightly different way to what you had done, but this way it works with the .then() pattern that promises use. This should give you an example of how you can handle the async code in your controller.
Note as well that my service is in the same module as my controller. This shouldn't matter and the way you've done it, injecting your factory module into your main module is fine.
angular.module('myApp', [])
//Define your controller
.controller('myCtrl', ['$scope','myFactory', function($scope,myFactory) {
//call async function from service, with .then pattern:
myFactory.myFunction().then(
function(data){
// Call function that does your map reduce
$scope.totalErrors = setTotalErrors();
},
function(error){
console.log(error);
});
function setTotalErrors () {
if ($scope.tiles){
var topLevel = $scope.tiles.data
console.log (topLevel);
return topLevel[0].issues.map(function(o) {
return o.errors.length
})
.reduce(function (prev, curr){
return prev + curr
});
}
}
}])
.factory('myFactory', ['$timeout','$q',function($timeout,$q){
return {
myFunction : myFunction
};
function myFunction(){
//Create deferred object with $q.
var deferred = $q.defer();
//mock an async call with a timeout
$timeout(function(){
//resolve the promise with the sample data
deferred.resolve(
{'data':[
{'issues':[
{'name':'Test','errors':[
{'id':1,'level':2},
{'id':3,'level':1},
{'id':5,'level':1},
{'id':5,'level':1}
]},
{'name':'Test','errors':[
{'id':1,'level':2,'details':{}},
{'id':5,'level':1}
]}
]}
]})
},200);
//return promise object.
return deferred.promise;
}
}]);
Have a look : Link to codepen
Also, have a read of the $q documentation: documentation
I'm trying to pass data from one controller to another using a service, however no matter what I'm trying it always returns 'undefined' on the second controller. Here is my service :
app.service('myService', ['$rootScope', '$http', function ($rootScope, $http) {
var savedData = {}
this.setData = function (data) {
savedData = data;
console.log('Data saved !', savedData);
}
this.getData = function get() {
console.log('Data used !', savedData);
return this.savedData;
}
}]);
Here is controller1 :
.controller('HomeCtrl', ['$scope','$location','$firebaseSimpleLogin','myService','$cookies','$window', function($scope,$location, $firebaseSimpleLogin, myService, $cookies, $window) {
loginObj.$login('password', {
email: username,
password: password
})
.then(function(user) {
// Success callback
console.log('Authentication successful');
myService.setData(user);
console.log('myservice:', myService.getData()); // works fine
}]);
And then controller2:
// Dashboard controller
.controller('DashboardCtrl', ['$scope','$firebaseSimpleLogin','myService',function($scope,$firebaseSimpleLogin, $location, myService) {
console.log('myservice:', myService.getData()); //returns undefined
}]);
That is simple code, unfortunately I've been struggling for a few hours now, any suggestion ? Thanks.
Created a fiddle here:
http://jsfiddle.net/frishi/8yn3nhfw/16
To isolate the problem, can you remove the dependencies from the definition for myService and see if that makes it work? Look at the console after you load the fiddle.
var app = angular.module('app', [])
.service('myService', function(){
this.getData = function(){
return "got Data";
}
})
I assume the issue is that you are returning this.savedData in the service. Try returning savedData.
this behaves different in Javascript than in other languages.
I'm not able to get the data binding between controller and service working.
I have a controller and a factory which makes an HTTP call. I would like to be able to call the factory method from other services and see the controller attributes get updated. I tried different options but none of them seem to be working. Any ideas would be greatly appreciated.
Please see the code here:
http://plnkr.co/edit/d3c16z?p=preview
Here is the javascript code.
var app = angular.module('plunker', []);
app.controller('MainCtrl', function($scope) {
$scope.name = 'World';
});
app.controller('EventDetailCtrl', ['$http', 'EventDetailSvc', '$scope',
function ($http, EventDetailSvc, $scope) {
this.event = EventDetailSvc.event;
EventDetailSvc.getEvent();
console.log(self.event);
$scope.$watch(angular.bind(this, function () {
console.log('under watch');
console.log(this.event);
return this.event;
}), function (newVal, oldVal) {
console.log('under watch2');
console.log(newVal);
this.event = newVal;
});
}])
.factory('EventDetailSvc', ['$http', function ($http) {
var event = {};
var factory = {};
factory.getEvent = function() {
$http.get('http://ip.jsontest.com')
.then(function (response) {
this.event = response.data;
console.log('http successful');
console.log(this.event);
return this.event;
}, function (errResponse) {
console.error("error while retrieving event");
})
};
factory.event = event;
return factory;
}]);
It seems to me that you have nested the event object inside of a factory object. You should be returning event directly instead wrapping it with factory. As it stands now you would need to call EventDetailSvc.factory.event to access your object.
I have a basic data Service which will be used across Controllers. But I'm having an issue grabbing some data that's been added via $http.
Service:
angular.module('core').service('FormService', ['$http', function($http) {
var _this = this;
_this.dropdownData = {
contactTimes: ['Anytime','Morning','Afternoon','Evening'],
industries: {},
};
$http.get('/json').success(function(resp){
_this.dropdownData.industries = resp.industries;
});
}]);
Controller:
angular.module('core').controller('SignupController', ['$scope', '$http', '$state', 'FormService', function($scope, $http, $state, FormService) {
console.log(FormService.dropdownData); // Shows full object incl industries
console.log(FormService.dropdownData.industries); // empty object {}
}]);
How do I get FormService.dropdownData.industries in my controller?
Create a service like below
appService.factory('Service', function ($http) {
return {
getIndustries: function () {
return $http.get('/json').then(function (response) {
return response.data;
});
}
}
});
Call in controller
appCtrl.controller('personalMsgCtrl', ['$scope', 'Service', function ($scope, Service) {
$scope.Industries = Service.getIndustries();
}]);
Hope this will help
Add a method to your service and use $Http.get inside that like below
_this.getindustries = function (callback) {
return $http.get('/json').success(function(resp){
_this.dropdownData.industries = resp.industries;
callback(_this.dropdownData)
});
};
In your controller need to access it like below.
angular.module('core').controller('myController', ['$scope', 'FormService', function ($scope, FormService) {
FormService.getDropdownData(function (dropdownData) {
console.log(dropdownData); // Shows full object incl industries
console.log(dropdownData.industries); // object {}
});
} ]);
Given that your console log shows the correct object, that shows your service is functioning properly. Only one small mistake you have made here. You need to access the data attributes in your return promise.
angular.module('core').service('FormService', ['$http', function($http) {
var _this = this;
_this.dropdownData = {
contactTimes: ['Anytime','Morning','Afternoon','Evening'],
industries: {},
};
$http.get('/json').success(function(resp){
//note that this is resp.data.industries, NOT resp.industries
_this.dropdownData.industries = resp.data.industries;
});
}]);
Assuming that you're data is indeed existing and there are no problems with the server, there are quite a few possible solutions
Returning a promise
angular.module('core').service('FormService', ['$http', function($http) {
var _this = this;
_this.dropdownData = {
contactTimes: ['Anytime','Morning','Afternoon','Evening'],
industries: {},
};
_this.dropdownData.industries = $http.get('/json');
}]);
//Controller
FormService.industries
.then(function(res){
$scope.industries = res.industries
});
Resolving with routeProvider / ui-route
See: $http request before AngularJS app initialises?
You could also write a function to initialize the service when the application starts running. At the end of the day, it is about waiting for the data to be loaded by using a promise. If you never heard about promises before, inform yourself first.
The industries object will be populated at a later point in time when the $http call returns. In the meantime you can still bind to the reference in your view because you've preserved the reference using angular.copy. When the $http call returns, the view will automatically be updated.
It is also a good idea to allow users of your service to handle the event when the $http call returns. You can do this by saving the $promise object as a property of industries:
angular.module('core').service('FormService', ['$http', function($http) {
var _this = this;
_this.dropdownData = {
contactTimes: ['Anytime','Morning','Afternoon','Evening'],
industries: {},
};
_this.dropdownData.industries.$promise = $http.get('/json').then(function(resp){
// when the ansyc call returns, populate the object,
// but preserve the reference
angular.copy( resp.data.industries, _this.dropdownData.industries);
return _this.dropdownData.industries;
});
}]);
Controller
app.controller('ctrl', function($scope, FormService){
// you can bind this to the view, even though the $http call has not returned yet
// the view will update automatically since the reference was preserved
$scope.dropdownData = FormService.dropdownData;
// alternatively, you can hook into the $http call back through the $promise
FormService.dropdownData.industries.$promise.success(function(industries) {
console.log(industries);
});
});
I have defined a service with functions like this:
angular.module('common').factory('_o', ['$angularCacheFactory', '$http', '$q', '$resource', '$timeout', '_u',
function ($angularCacheFactory, $http, $q, $resource, $timeout, _u) {
var _getContentTypes = function ($scope) {
var defer = $q.defer();
$http.get('/api/ContentType/GetSelect', { cache: _u.oyc })
.success(function (data) {
$scope.option.contentTypes = data;
$scope.option.contentTypesPlus = [{ id: 0, name: '*' }].concat(data);
$scope.option.sContentType = parseInt(_u.oyc.get('sContentType')) || 0;
defer.resolve();
})
return defer.promise;
};
return {
getContentTypes: _getContentTypes
}
}]);
I am calling this in my controller like this:
.controller('AdminProblemController', ['$http', '$q', '$resource', '$rootScope', '$scope', '_g', '_o', '_u',
function ($http, $q, $resource, $rootScope, $scope, _g, _o, _u) {
$scope.entityType = "Problem";
_u.oyc.put('adminPage', $scope.entityType.toLowerCase());
$q.all([
_o.getContentTypes($scope),
_o.getABC($scope),
_o.getDEF($scope)
])
Am I correct in saying this is not the best way to use a service. I think I should be returning the
content type data and then in the controller assigning to the scope not in the service.
But I am not sure how to do this as my service just returns a defer.promise and I am using $q.all so I think I should populate the scope after $q.all has returned success for every call.
Can someone give me some advice on how I should return data from a service with a promise and have it populate the $scope after $q.all has completed with all calls successful ?
You are absolutely correct in saying that the controller should really be doing this, it would be much cleaner to remove the passing around of your scope (and make it more re-usable). I don't know your exact use case and it is a little confusing to read, but you can do this by hooking into the promises that are created by $http, as well as still handling when all of the promises have been completed.
fiddle: http://jsfiddle.net/PtM8N/3/
HTML
<div ng-app="myApp" ng-controller="Ctrl">
{{model | json}}
<div ng-show="loading">Loading...</div>
</div>
Angular
var app = angular.module("myApp", []);
app.service("_service", ["$http", function (http) {
this.firstRequest = function () {
return http.get("http://json.ph/json?delay=1000")
.then(function (res) {
// manipulate data
res.data.something = new Date();
return res.data;
});
};
this.secondRequest = function () {
return http.get("http://json.ph/json?delay=2000")
.then(function (res) {
// manipulate data
res.data.something = 12345;
return res.data;
});
};
this.thirdRequest = function () {
return http.get("http://json.ph/json?delay=3000")
.then(function (res) {
// manipulate data
res.data.something = "bacon";
return res.data;
});
};
}]);
app.controller("Ctrl", ["$scope", "_service", "$q", function (scope, service, q) {
scope.loading = true;
scope.model = {};
var firstRequest = service.firstRequest();
var secondRequest = service.secondRequest();
var thirdRequest = service.thirdRequest();
q.all([firstRequest, secondRequest, thirdRequest]).then(function (responses) {
scope.model.first = responses[0];
scope.model.second = responses[1];
scope.model.third = responses[2];
scope.loading = false;
});
}]);