Angular.js delaying controller initialization - javascript

I would like to delay the initialization of a controller until the necessary data has arrived from the server.
I found this solution for Angular 1.0.1: Delaying AngularJS route change until model loaded to prevent flicker, but couldn't get it working with Angular 1.1.0
Template
<script type="text/ng-template" id="/editor-tpl.html">
Editor Template {{datasets}}
</script>
<div ng-view>
</div>
​
JavaScript
function MyCtrl($scope) {
$scope.datasets = "initial value";
}
MyCtrl.resolve = {
datasets : function($q, $http, $location) {
var deferred = $q.defer();
//use setTimeout instead of $http.get to simulate waiting for reply from server
setTimeout(function(){
console.log("whatever");
deferred.resolve("updated value");
}, 2000);
return deferred.promise;
}
};
var myApp = angular.module('myApp', [], function($routeProvider) {
$routeProvider.when('/', {
templateUrl: '/editor-tpl.html',
controller: MyCtrl,
resolve: MyCtrl.resolve
});
});​
http://jsfiddle.net/dTJ9N/1/

Since $http returns a promise, it's a performance hit to create your own deferred just to return the promise when the http data arrives. You should be able to do:
MyCtrl.resolve = {
datasets: function ($http) {
return $http({method: 'GET', url: '/someUrl'});
}
};
If you need to do some processing of the result, use .then, and your promise is chained in for free:
MyCtrl.resolve = {
datasets: function ($http) {
return $http({method: 'GET', url: '/someUrl'})
.then (function (data) {
return frob (data);
});
}
};

You could always just put "ng-show" on the outer-most DOM element and set it equal to the data you want to wait for.
For the example listed on the Angular JS home page you can see how easy it is: http://plnkr.co/CQu8QB94Ra687IK6KgHn
All that had to be done was
That way the form won't show until that value has been set.
Much more intuitive and less work this way.

You can take a look at a near identical question here that uses resources, but it works the same way with $http. I think this should work
function MyCtrl($scope, datasets) {
$scope.datasets = datasets;
}
MyCtrl.resolve = {
datasets: function($http, $q) {
var deferred = $q.defer();
$http({method: 'GET', url: '/someUrl'})
.success(function(data) {
deferred.resolve(data)
}
return deferred.promise;
}
};
var myApp = angular.module('myApp', [], function($routeProvider) {
$routeProvider.when('/', {
templateUrl: '/editor-tpl.html',
controller: MyCtrl,
resolve: MyCtrl.resolve
});
});​

Related

Refactoring Angular controller into separate factory and controller

Learning Angular. Working with 1.6.6 right now.
In my initial stab, I put all my $http requests into my controller, so I'm trying to pull that out of the controller and into a factory for more reusable code. I think that I am missing something related to Promise or injection, but the data from my $http call is not being bound to $scope correctly.
I've been following along this guide.
I have a template that's begin loaded from the controller (the template is loading fine):
<form ng-init="getAllRegions()" ng-submit="getRandomTown()">
<h3>Generate Random Town</h3>
<div class="form-group-row">
<label for="selectRegion">Select Region:</label>
<select name="nameEntity"
id="selectRegion"
ng-model="guidEntity"
ng-options="item.guidEntity as item.nameEntity for item in regions">
<option value="" ng-if="!guidEntity"></option>
</select>
</div>
</form>
The ng-init function is being called, and passes through the controller and the service. In chrome inspector I can see that data is pulling through correctly, but I'm new to working with Promises, so I'm losing something along the way. This was all working as expected when the $http call was right in the controller and the data was being bound to $scope in the controller.
The controller:
angular.
module('randomTown.controller', []).
component('randomTownGenerator', {
templateUrl: 'js/components/randomTownGenerator/randomTownGenerator.tpl.html'
}).
controller('RandomTownCtrl',
function($scope, randomTownFactory) {
$scope.data = {};
$scope.getAllRegions = function () {
$scope.regions = randomTownFactory.getAllDBRegions();
}
}
);
The service:
angular.
module('randomTown.service', []).
factory('randomTownFactory', function ($q, $http) {
var service = {};
service.getAllDBRegions = function() {
var deferred = $q.defer();
$http({
method: 'GET',
url: '/all-regions'
}).then(function success(data) {
deferred.resolve(data);
}), function error(response) {
deferred.reject('There was an error');
}
return deferred.promise;
}
return service;
});
There is no need to manufacture a promise with $q.defer. Simply return the $http promise:
app.factory('randomTownFactory', function ($q, $http) {
var service = {};
service.getAllDBRegions = function() {
̶v̶a̶r̶ ̶d̶e̶f̶e̶r̶r̶e̶d̶ ̶=̶ ̶$̶q̶.̶d̶e̶f̶e̶r̶(̶)̶;̶
̲r̲e̲t̲u̲r̲n̲ $http({
method: 'GET',
url: '/all-regions'
}).then(function success( ̶d̶a̶t̶a̶ response) {
̶d̶e̶f̶e̶r̶r̶e̶d̶.̶r̶e̶s̶o̶l̶v̶e̶(̶d̶a̶t̶a̶)̶;̶
return response.data;
}),̶ ̶f̶u̶n̶c̶t̶i̶o̶n̶ ̶e̶r̶r̶o̶r̶(̶r̶e̶s̶p̶o̶n̶s̶e̶)̶ ̶{̶
̶d̶e̶f̶e̶r̶r̶e̶d̶.̶r̶e̶j̶e̶c̶t̶(̶'̶T̶h̶e̶r̶e̶ ̶w̶a̶s̶ ̶a̶n̶ ̶e̶r̶r̶o̶r̶'̶)̶;̶
̶}̶
̶r̶e̶t̶u̶r̶n̶ ̶d̶e̶f̶e̶r̶r̶e̶d̶.̶p̶r̶o̶m̶i̶s̶e̶;̶,
}
return service;
});
Also notice that the success handler does not reveal the data. It reveals a response object of which data is one of the properties.
The controller:
app.controller('RandomTownCtrl',
function($scope, randomTownFactory) {
$scope.getAllRegions = function () {
var promise = randomTownFactory.getAllDBRegions();
promise.then(function(data) {
$scope.regions = data;
}).catch(function(errorResponse) {
console.log("ERROR", errorResponse.status)
});
}
}
);
For more information, see
AngularJS $http service API Reference
You're Missing the Point of Promises
Try this:
$scope.getAllRegions = function () {
randomTownFactory.getAllDBRegions()
.then((regions) => {$scope.regions = regions});
}
Why: because etAllDBRegions returns a promise, so you have to use then property to get the result

AngularJS load controller after resolve doesn't work

Goal:
In my application every controller should be initialized after a user has a session / is logged in, because in this controller I use the data of logged in user.
Code:
app.js
app.run(function($q, $rootScope, AuthSvc){
$rootScope.ajaxCall = $q.defer();
AuthSvc.reloadSession().then(
function(response){
if(response!=null && response!=undefined){
$rootScope.activeUserSession = response;
$rootScope.ajaxCall.resolve();
}else{
$rootScope.activeUserSession = null;
$rootScope.ajaxCall.reject();
}
});
return $rootScope.ajaxCall.promise;
});
routes.js
.config(['$routeProvider',
function($routeProvider) {
$routeProvider.
when('/timeTracking', {
templateUrl: 'partials/timeTracking/projectView.html',
controller: 'timeTrackingController',
resolve: {
response: function($rootScope, $q) {
var defer = $q.defer();
$rootScope.ajaxCall.promise.then(
function(){
defer.resolve();
return defer.promise;
});
}
}
}).
Problem: Controller gets initialized sometimes before the user has a session, I do not understand why.
Sorry I am new to Angular and my english is also crap, so I hope nevertheless you can understand what is my problem.
I think placing your session reload into the app.run is not the right place. Add it directly to resolve and checkout the docs for $q to learn how promises are working.
Because you can't call a promise or defer. You need to call a function that's returning a promise then you can add your then method to do your stuff after the promise is resolved.
Please have a look at the demo below or here at jsfiddle.
It's just an asynchronous method with $timeout to simulate the auth because I don't have a backend to add in the demo.
You can add your AuthSvc directly into resolve.
angular.module('demoApp', ['ngRoute'])
.controller('timeTrackingController', function($scope, response) {
$scope.data = response;
})
.factory('authService', function($q, $timeout) {
return {
reloadSession: function() {
var deferred = $q.defer();
$timeout(function() {
// just simulate session reload
// real api would to the job here
console.log('resolved defer now!!');
deferred.resolve({dummyData: 'hello from service'});
}, 1000);
return deferred.promise;
}
}
})
.config(['$routeProvider',
function($routeProvider) {
$routeProvider.
when('/timeTracking', {
templateUrl: 'partials/timeTracking/projectView.html',
controller: 'timeTrackingController',
resolve: {
response: function(authService) {
return authService.reloadSession().then(function(data) {
return data;
})
}
}
})
.otherwise('/timeTracking');
}]);
<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.4.3/angular.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.4.3/angular-route.js"></script>
<div ng-app="demoApp">
<script type="text/ng-template" id="partials/timeTracking/projectView.html">
project view: {{data | json}}
</script>
<div ng-view=""></div>
</div>

AngularJS App: Load data from JSON once and use it in several controllers

I'm working on a mobile app using AngularJS as a framework, currently I have a structure similar to this:
app.config(['$routeProvider', function($routeProvider) {
$routeProvider
.when('/', {
templateUrl : 'pages/home.html',
controller : 'homeCtrl'
})
.when('/one', {
templateUrl : 'pages/one.html',
controller : 'oneCtrl'
})
.when('/two', {
templateUrl : 'pages/two.html',
controller : 'twoCtrl'
});
}]);
app.controller('homeCtrl', ['$scope', function($scope) {
}]);
app.controller('oneCtrl', ['$scope', function($scope) {
}]);
app.controller('twoCtrl', ['$scope', function($scope) {
}]);
And then I'm displaying the content with an ng-view:
<div class="ng-view></div>
Things are working well but I need to load data from a JSON file to populate all the content of the app. What I want is to make and an AJAX call only once and then pass the data through all my different controllers. In my first attempt, I thought to create a Service with an $http.get() inside of it and include that in every controller, but it does not work because it makes a different ajax request everytime I inject and use the service. Since I'm new using angular I'm wondering what is the best way or the more "angular way" to achieve this without messing it up.
Edit: I'm adding the code of the service, which is just a simple $http.get request:
app.service('Data', ['$http', function($http) {
this.get = function() {
$http.get('data.json')
.success(function(result) {
return result;
})
}
});
Initialize the promise once, and return a reference to it:
No need to initialize another promise. $http returns one.
Just tack a .then() call on your promise to modify the result
angular.module('app', [])
.service('service', function($http){
this.promise = null;
function makeRequest() {
return $http.get('http://jsonplaceholder.typicode.com/posts/1')
.then(function(resp){
return resp.data;
});
}
this.getPromise = function(update){
if (update || !this.promise) {
this.promise = makeRequest();
}
return this.promise;
}
})
Codepen example
Edit: you may consider using $http cache instead. It can achieve the same results. From the docs:
If multiple identical requests are made using the same cache, which is not yet populated, one request will be made to the server and remaining requests will return the same response.
Try this to get JSON Data from a GET Link:
(function (app) {
'use strict';
app.factory('myService', MyService);
MyService.$inject = ['$q', '$http'];
function MyService($q, $http) {
var data;
var service = {
getData: getData
};
return service;
//////////////////////////////////////
function getData(refresh) {
if (refresh || !data) {
return $http.get('your_source').then(function(data){
this.data = data;
return data;
})
}
else {
var deferrer = $q.defer();
deferrer.resolve(data);
return deferrer.promise;
}
}
}
}(angular.module('app')));
Now you can add this dependency in your controller file and use:
myService.getData().then(function(data){
//use data here
}, function(err){
//Handle error here
});

Angularjs ng-controller with resolve

I've ran into problem with ng-controller and 'resolve' functionality:
I have a controller that requires some dependency to be resolved before running, it works fine when I define it via ng-route:
Controller code looks like this:
angular.module('myApp')
.controller('MyController', ['$scope', 'data', function ($scope, data) {
$scope.data = data;
}
]
);
Routing:
...
.when('/someUrl', {
templateUrl : 'some.html',
controller : 'MyController',
resolve : {
data: ['Service', function (Service) {
return Service.getData();
}]
}
})
...
when I go to /someUrl, everything works.
But I need to use this controller in other way(I need both ways in different places):
<div ng-controller="MyController">*some html here*</div>
And, of course, it fails, because 'data' dependency wasn't resolved. Is there any way to inject dependency into controller when I use 'ng-controller' or I should give up and load data inside controller?
In the below, for the route resolve, we're resolving the promise and wrapping the return data in an object with a property. We then duplicate this structure in the wrapper service ('dataService') that we use for the ng-controller form.
The wrapper service also resolves the promise but does so internally, and updates a property on the object we've already returned to be consumed by the controller.
In the controller, you could probably put a watcher on this property if you wanted to delay some additional behaviours until after everything was resolved and the data was available.
Alternatively, I've demonstrated using a controller that 'wraps' another controller; once the promise from Service is resolved, it then passes its own $scope on to the wrapped controller as well as the now-resolved data from Service.
Note that I've used $timeout to provide a 1000ms delay on the promise return, to try and make it a little more clear what's happening and when.
angular.module('myApp', ['ngRoute'])
.config(function($routeProvider) {
$routeProvider
.when('/', {
template: '<h1>{{title}}</h1><p>{{blurb}}</p><div ng-controller="ResolveController">Using ng-controller: <strong>{{data.data}}</strong></div>',
controller: 'HomeController'
})
.when('/byResolve', {
template: '<h1>{{title}}</h1><p>{{blurb}}</p><p>Resolved: <strong>{{data.data}}</strong></p>',
controller: "ResolveController",
resolve: {
dataService: ['Service',
function(Service) {
// Here getData() returns a promise, so we can use .then.
// I'm wrapping the result in an object with property 'data', so we're returning an object
// which can be referenced, rather than a string which would only be by value.
// This mirrors what we return from dataService (which wraps Service), making it interchangeable.
return Service.getData().then(function(result) {
return {
data: result
};
});
}
]
}
})
.when('/byWrapperController', {
template: '<h1>Wrapped: {{title}}</h1><p>{{blurb}}</p><div ng-controller="WrapperController">Resolving and passing to a wrapper controller: <strong>{{data.data ? data.data : "Loading..."}}</strong></div>',
controller: 'WrapperController'
});
})
.controller('HomeController', function($scope) {
$scope.title = "ng-controller";
$scope.blurb = "Click 'By Resolve' above to trigger the next route and resolve.";
})
.controller('ResolveController', ['$scope', 'dataService',
function($scope, dataService) {
$scope.title = "Router and resolve";
$scope.blurb = "Click 'By ng-controller' above to trigger the original route and test ng-controller and the wrapper service, 'dataService'.";
$scope.data = dataService;
}
])
.controller('WrapperController', ['$scope', '$controller', 'Service',
function($scope, $controller, Service) {
$scope.title = "Resolving..."; //this controller could of course not show anything until after the resolve, but demo purposes...
Service.getData().then(function(result) {
$controller('ResolveController', {
$scope: $scope, //passing the same scope on through
dataService: {
data: result
}
});
});
}
])
.service('Service', ['$timeout',
function($timeout) {
return {
getData: function() {
//return a test promise
return $timeout(function() {
return "Data from Service!";
}, 1000);
}
};
}
])
// our wrapper service, that will resolve the promise internally and update a property on an object we can return (by reference)
.service('dataService', function(Service) {
// creating a return object with a data property, matching the structure we return from the router resolve
var _result = {
data: null
};
Service.getData().then(function(result) {
_result.data = result;
return result;
});
return _result;
});
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.27/angular.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.27/angular-route.min.js"></script>
<div ng-app="myApp">
By ng-controller |
By Resolve |
By Wrapper Controller
<div ng-view />
</div>
Create a new module inside which you have the service to inject like seen below.
var module = angular.module('myservice', []);
module.service('userService', function(Service){
return Service.getData();
});
Inject newly created service module inside your app module
angular.module('myApp')
.controller('MyController', ['$scope', 'myservice', function ($scope, myservice) {
$scope.data = data;
// now you can use new dependent service anywhere here.
}
]
);
You can use the mechanism of the prototype.
.when('/someUrl', {
template : '<div ng-controller="MyController" ng-template="some.html"></div>',
controller: function (data) {
var pr = this;
pr.data = data;
},
controllerAs: 'pr',
resolve : {
data: ['Service', function (Service) {
return Service.getData();
}]
}
})
angular.module('myApp')
.controller('MyController', ['$scope', function ($scope) {
$scope.data = $scope.pr.data; //magic
}
]
);
Now wherever you want to use
'<div ng-controller="MyController"></div>'
you need to ensure that there pr.data in the Scope of the calling controller. As an example uib-modal
var modalInstance = $modal.open({
animation: true,
templateUrl: 'modal.html',
resolve: {
data: ['Service', function (Service) {
return Service.getData();
}]
},
controller: function ($scope, $modalInstance, data) {
var pr = this;
pr.data = data;
pr.ok = function () {
$modalInstance.close();
};
},
controllerAs:'pr',
size:'sm'
});
modal.html
<script type="text/ng-template" id="modal.html">
<div class="modal-body">
<div ng-include="some.html" ng-controller="MyController"></div>
</div>
<div class="modal-footer">
<button class="btn btn-primary pull-right" type="button" ng-click="pr.ok()">{{ 'ok' | capitalize:'first'}}</button>
</div>
</script>
And now you can use $scope.data = $scope.pr.data; in MyController
pr.data is my style. You can rewrite the code without PR.
the basic principle of working with ng-controller described in this video https://egghead.io/lessons/angularjs-the-dot
Presuming that Service.getData() returns a promise, MyController can inject that Service as well. The issue is that you want to delay running the controller until the promise resolves. While the router does this for you, using the controller directly means that you have to build that logic.
angular.module('myApp')
.controller('MyController', ['$scope', 'Service', function ($scope, Service) {
$scope.data = {}; // default values for data
Service.getData().then(function(data){
// data is now resolved... do stuff with it
$scope.data = data;
});
}]
);
Now this works great when using the controller directly, but in your routing example, where you want to delay rendering a page until data is resolved, you are going to end up making two calls to Service.getData(). There are a few ways to work around this issue, like having Service.getData() return the same promise for all caller, or something like this might work to avoid the second call entirely:
angular.module('myApp')
.controller('MyController', ['$scope', '$q', 'Service', function ($scope, $q, Service) {
var dataPromise,
// data might be provided from router as an optional, forth param
maybeData = arguments[3]; // have not tried this before
$scope.data = {}; //default values
// if maybeData is available, convert it to a promise, if not,
// get a promise for fetching the data
dataPromise = !!maybeData?$q.when(maybeData):Service.getData();
dataPromise.then(function(data){
// data is now resolved... do stuff with it
$scope.data = data;
});
}]
);
I was trying to solve the problem using ng-init but came across the following warnings on angularjs.org
The only appropriate use of ngInit is for aliasing special properties
of ngRepeat, as seen in the demo below. Besides this case, you should
use controllers rather than ngInit to initialize values on a scope.
So I started searching for something like ng-resolve and came across the following thread:
https://github.com/angular/angular.js/issues/2092
The above link consists of a demo fiddle that have ng-resolve like functionality. I think ng-resolve can become a feature in the future versions of angular 1.x. For now we can work around with the directive mentioned in the above link.
'data' from route resolve will not be available for injection to a controller activated other than route provider. it will be available only to the view configured in the route provider.
if you want the data to the controller activated directly other than routeprovider activation, you need to put a hack for it.
see if this link helps for it:
http://www.johnpapa.net/route-resolve-and-controller-activate-in-angularjs/
Getting data in "resolve" attribute is the functionality of route (routeProvider) , not the functionality of controller.
Key( is your case : 'data') in resolve attribute is injected as service.
That's why we are able fetch data from that service.
But to use same controller in different place , you have fetch data in controller.
Try this
Service:
(function() {
var myService = function($http) {
var getData = function() {
//return your result
};
return {
getData:getData
};
};
var myApp = angular.module("myApp");
myApp.factory("myService", myService);
}());
Controller:
(function () {
var myApp = angular.module("myApp");
myApp.controller('MyController', [
'$scope', 'myService', function($scope, myService) {
$scope.data = myService.getData();
}
]);
//Routing
.when('/someUrl', {
templateUrl : 'some.html',
controller : 'MyController',
resolve : {
data: $scope.data,
}
})
}());

Delaying AngularJS route change until model loaded to prevent flicker

I am wondering if there is a way (similar to Gmail) for AngularJS to delay showing a new route until after each model and its data has been fetched using its respective services.
For example, if there were a ProjectsController that listed all Projects and project_index.html which was the template that showed these Projects, Project.query() would be fetched completely before showing the new page.
Until then, the old page would still continue to show (for example, if I were browsing another page and then decided to see this Project index).
$routeProvider resolve property allows delaying of route change until data is loaded.
First define a route with resolve attribute like this.
angular.module('phonecat', ['phonecatFilters', 'phonecatServices', 'phonecatDirectives']).
config(['$routeProvider', function($routeProvider) {
$routeProvider.
when('/phones', {
templateUrl: 'partials/phone-list.html',
controller: PhoneListCtrl,
resolve: PhoneListCtrl.resolve}).
when('/phones/:phoneId', {
templateUrl: 'partials/phone-detail.html',
controller: PhoneDetailCtrl,
resolve: PhoneDetailCtrl.resolve}).
otherwise({redirectTo: '/phones'});
}]);
notice that the resolve property is defined on route.
function PhoneListCtrl($scope, phones) {
$scope.phones = phones;
$scope.orderProp = 'age';
}
PhoneListCtrl.resolve = {
phones: function(Phone, $q) {
// see: https://groups.google.com/forum/?fromgroups=#!topic/angular/DGf7yyD4Oc4
var deferred = $q.defer();
Phone.query(function(successData) {
deferred.resolve(successData);
}, function(errorData) {
deferred.reject(); // you could optionally pass error data here
});
return deferred.promise;
},
delay: function($q, $defer) {
var delay = $q.defer();
$defer(delay.resolve, 1000);
return delay.promise;
}
}
Notice that the controller definition contains a resolve object which declares things which should be available to the controller constructor. Here the phones is injected into the controller and it is defined in the resolve property.
The resolve.phones function is responsible for returning a promise. All of the promises are collected and the route change is delayed until after all of the promises are resolved.
Working demo: http://mhevery.github.com/angular-phonecat/app/#/phones
Source: https://github.com/mhevery/angular-phonecat/commit/ba33d3ec2d01b70eb5d3d531619bf90153496831
Here's a minimal working example which works for Angular 1.0.2
Template:
<script type="text/ng-template" id="/editor-tpl.html">
Editor Template {{datasets}}
</script>
<div ng-view>
</div>
JavaScript:
function MyCtrl($scope, datasets) {
$scope.datasets = datasets;
}
MyCtrl.resolve = {
datasets : function($q, $http) {
var deferred = $q.defer();
$http({method: 'GET', url: '/someUrl'})
.success(function(data) {
deferred.resolve(data)
})
.error(function(data){
//actually you'd want deffered.reject(data) here
//but to show what would happen on success..
deferred.resolve("error value");
});
return deferred.promise;
}
};
var myApp = angular.module('myApp', [], function($routeProvider) {
$routeProvider.when('/', {
templateUrl: '/editor-tpl.html',
controller: MyCtrl,
resolve: MyCtrl.resolve
});
});​
​
http://jsfiddle.net/dTJ9N/3/
Streamlined version:
Since $http() already returns a promise (aka deferred), we actually don't need to create our own. So we can simplify MyCtrl. resolve to:
MyCtrl.resolve = {
datasets : function($http) {
return $http({
method: 'GET',
url: 'http://fiddle.jshell.net/'
});
}
};
The result of $http() contains data, status, headers and config objects, so we need to change the body of MyCtrl to:
$scope.datasets = datasets.data;
http://jsfiddle.net/dTJ9N/5/
I see some people asking how to do this using the angular.controller method with minification friendly dependency injection. Since I just got this working I felt obliged to come back and help. Here's my solution (adopted from the original question and Misko's answer):
angular.module('phonecat', ['phonecatFilters', 'phonecatServices', 'phonecatDirectives']).
config(['$routeProvider', function($routeProvider) {
$routeProvider.
when('/phones', {
templateUrl: 'partials/phone-list.html',
controller: PhoneListCtrl,
resolve: {
phones: ["Phone", "$q", function(Phone, $q) {
var deferred = $q.defer();
Phone.query(function(successData) {
deferred.resolve(successData);
}, function(errorData) {
deferred.reject(); // you could optionally pass error data here
});
return deferred.promise;
]
},
delay: ["$q","$defer", function($q, $defer) {
var delay = $q.defer();
$defer(delay.resolve, 1000);
return delay.promise;
}
]
},
}).
when('/phones/:phoneId', {
templateUrl: 'partials/phone-detail.html',
controller: PhoneDetailCtrl,
resolve: PhoneDetailCtrl.resolve}).
otherwise({redirectTo: '/phones'});
}]);
angular.controller("PhoneListCtrl", [ "$scope", "phones", ($scope, phones) {
$scope.phones = phones;
$scope.orderProp = 'age';
}]);
Since this code is derived from the question/most popular answer it is untested, but it should send you in the right direction if you already understand how to make minification friendly angular code. The one part that my own code didn't requires was an injection of "Phone" into the resolve function for 'phones', nor did I use any 'delay' object at all.
I also recommend this youtube video http://www.youtube.com/watch?v=P6KITGRQujQ&list=UUKW92i7iQFuNILqQOUOCrFw&index=4&feature=plcp , which helped me quite a bit
Should it interest you I've decided to also paste my own code (Written in coffeescript) so you can see how I got it working.
FYI, in advance I use a generic controller that helps me do CRUD on several models:
appModule.config ['$routeProvider', ($routeProvider) ->
genericControllers = ["boards","teachers","classrooms","students"]
for controllerName in genericControllers
$routeProvider
.when "/#{controllerName}/",
action: 'confirmLogin'
controller: 'GenericController'
controllerName: controllerName
templateUrl: "/static/templates/#{controllerName}.html"
resolve:
items : ["$q", "$route", "$http", ($q, $route, $http) ->
deferred = $q.defer()
controllerName = $route.current.controllerName
$http(
method: "GET"
url: "/api/#{controllerName}/"
)
.success (response) ->
deferred.resolve(response.payload)
.error (response) ->
deferred.reject(response.message)
return deferred.promise
]
$routeProvider
.otherwise
redirectTo: '/'
action: 'checkStatus'
]
appModule.controller "GenericController", ["$scope", "$route", "$http", "$cookies", "items", ($scope, $route, $http, $cookies, items) ->
$scope.items = items
#etc ....
]
This commit, which is part of version 1.1.5 and above, exposes the $promise object of $resource. Versions of ngResource including this commit allow resolving resources like this:
$routeProvider
resolve: {
data: function(Resource) {
return Resource.get().$promise;
}
}
controller
app.controller('ResourceCtrl', ['$scope', 'data', function($scope, data) {
$scope.data = data;
}]);
This snippet is dependency injection friendly (I even use it in combination of ngmin and uglify) and it's a more elegant domain driven based solution.
The example below registers a Phone resource and a constant phoneRoutes, which contains all your routing information for that (phone) domain. Something I didn't like in the provided answer was the location of the resolve logic -- the main module should not know anything or be bothered about the way the resource arguments are provided to the controller. This way the logic stays in the same domain.
Note: if you're using ngmin (and if you're not: you should) you only have to write the resolve functions with the DI array convention.
angular.module('myApp').factory('Phone',function ($resource) {
return $resource('/api/phone/:id', {id: '#id'});
}).constant('phoneRoutes', {
'/phone': {
templateUrl: 'app/phone/index.tmpl.html',
controller: 'PhoneIndexController'
},
'/phone/create': {
templateUrl: 'app/phone/edit.tmpl.html',
controller: 'PhoneEditController',
resolve: {
phone: ['$route', 'Phone', function ($route, Phone) {
return new Phone();
}]
}
},
'/phone/edit/:id': {
templateUrl: 'app/phone/edit.tmpl.html',
controller: 'PhoneEditController',
resolve: {
form: ['$route', 'Phone', function ($route, Phone) {
return Phone.get({ id: $route.current.params.id }).$promise;
}]
}
}
});
The next piece is injecting the routing data when the module is in the configure state and applying it to the $routeProvider.
angular.module('myApp').config(function ($routeProvider,
phoneRoutes,
/* ... otherRoutes ... */) {
$routeProvider.when('/', { templateUrl: 'app/main/index.tmpl.html' });
// Loop through all paths provided by the injected route data.
angular.forEach(phoneRoutes, function(routeData, path) {
$routeProvider.when(path, routeData);
});
$routeProvider.otherwise({ redirectTo: '/' });
});
Testing the route configuration with this setup is also pretty easy:
describe('phoneRoutes', function() {
it('should match route configuration', function() {
module('myApp');
// Mock the Phone resource
function PhoneMock() {}
PhoneMock.get = function() { return {}; };
module(function($provide) {
$provide.value('Phone', FormMock);
});
inject(function($route, $location, $rootScope, phoneRoutes) {
angular.forEach(phoneRoutes, function (routeData, path) {
$location.path(path);
$rootScope.$digest();
expect($route.current.templateUrl).toBe(routeData.templateUrl);
expect($route.current.controller).toBe(routeData.controller);
});
});
});
});
You can see it in full glory in my latest (upcoming) experiment.
Although this method works fine for me, I really wonder why the $injector isn't delaying construction of anything when it detects injection of anything that is a promise object; it would make things soooOOOOOooOOOOO much easier.
Edit: used Angular v1.2(rc2)
Delaying showing the route is sure to lead to an asynchronous tangle... why not simply track the loading status of your main entity and use that in the view. For example in your controller you might use both the success and error callbacks on ngResource:
$scope.httpStatus = 0; // in progress
$scope.projects = $resource.query('/projects', function() {
$scope.httpStatus = 200;
}, function(response) {
$scope.httpStatus = response.status;
});
Then in the view you could do whatever:
<div ng-show="httpStatus == 0">
Loading
</div>
<div ng-show="httpStatus == 200">
Real stuff
<div ng-repeat="project in projects">
...
</div>
</div>
<div ng-show="httpStatus >= 400">
Error, not found, etc. Could distinguish 4xx not found from
5xx server error even.
</div>
I worked from Misko's code above and this is what I've done with it. This is a more current solution since $defer has been changed to $timeout. Substituting $timeout however will wait for the timeout period (in Misko's code, 1 second), then return the data hoping it's resolved in time. With this way, it returns asap.
function PhoneListCtrl($scope, phones) {
$scope.phones = phones;
$scope.orderProp = 'age';
}
PhoneListCtrl.resolve = {
phones: function($q, Phone) {
var deferred = $q.defer();
Phone.query(function(phones) {
deferred.resolve(phones);
});
return deferred.promise;
}
}
Using AngularJS 1.1.5
Updating the 'phones' function in Justen's answer using AngularJS 1.1.5 syntax.
Original:
phones: function($q, Phone) {
var deferred = $q.defer();
Phone.query(function(phones) {
deferred.resolve(phones);
});
return deferred.promise;
}
Updated:
phones: function(Phone) {
return Phone.query().$promise;
}
Much shorter thanks to the Angular team and contributors. :)
This is also the answer of Maximilian Hoffmann. Apparently that commit made it into 1.1.5.
You can use $routeProvider resolve property to delay route change until data is loaded.
angular.module('app', ['ngRoute']).
config(['$routeProvider', function($routeProvider, EntitiesCtrlResolve, EntityCtrlResolve) {
$routeProvider.
when('/entities', {
templateUrl: 'entities.html',
controller: 'EntitiesCtrl',
resolve: EntitiesCtrlResolve
}).
when('/entity/:entityId', {
templateUrl: 'entity.html',
controller: 'EntityCtrl',
resolve: EntityCtrlResolve
}).
otherwise({redirectTo: '/entities'});
}]);
Notice that the resolve property is defined on route.
EntitiesCtrlResolve and EntityCtrlResolve is constant objects defined in same file as EntitiesCtrl and EntityCtrl controllers.
// EntitiesCtrl.js
angular.module('app').constant('EntitiesCtrlResolve', {
Entities: function(EntitiesService) {
return EntitiesService.getAll();
}
});
angular.module('app').controller('EntitiesCtrl', function(Entities) {
$scope.entities = Entities;
// some code..
});
// EntityCtrl.js
angular.module('app').constant('EntityCtrlResolve', {
Entity: function($route, EntitiesService) {
return EntitiesService.getById($route.current.params.projectId);
}
});
angular.module('app').controller('EntityCtrl', function(Entity) {
$scope.entity = Entity;
// some code..
});
I like darkporter's idea because it will be easy for a dev team new to AngularJS to understand and worked straight away.
I created this adaptation which uses 2 divs, one for loader bar and another for actual content displayed after data is loaded. Error handling would be done elsewhere.
Add a 'ready' flag to $scope:
$http({method: 'GET', url: '...'}).
success(function(data, status, headers, config) {
$scope.dataForView = data;
$scope.ready = true; // <-- set true after loaded
})
});
In html view:
<div ng-show="!ready">
<!-- Show loading graphic, e.g. Twitter Boostrap progress bar -->
<div class="progress progress-striped active">
<div class="bar" style="width: 100%;"></div>
</div>
</div>
<div ng-show="ready">
<!-- Real content goes here and will appear after loading -->
</div>
See also: Boostrap progress bar docs
I liked above answers and learned a lot from them but there is something that is missing in most of the above answers.
I was stuck in a similar scenario where I was resolving url with some data that is fetched in the first request from the server. Problem I faced was what if the promise is rejected.
I was using a custom provider which used to return a Promise which was resolved by the resolve of $routeProvider at the time of config phase.
What I want to stress here is the concept of when it does something like this.
It sees the url in url bar and then respective when block in called controller and view is referred so far so good.
Lets say I have following config phase code.
App.when('/', {
templateUrl: '/assets/campaigns/index.html',
controller: 'CampaignListCtr',
resolve : {
Auth : function(){
return AuthServiceProvider.auth('campaign');
}
}
})
// Default route
.otherwise({
redirectTo: '/segments'
});
On root url in browser first block of run get called otherwise otherwise gets called.
Let's imagine a scenario I hit rootUrl in address bar AuthServicePrivider.auth() function gets called.
Lets say Promise returned is in reject state what then???
Nothing gets rendered at all.
Otherwise block will not get executed as it is for any url which is not defined in the config block and is unknown to angularJs config phase.
We will have to handle the event that gets fired when this promise is not resolved. On failure $routeChangeErorr gets fired on $rootScope.
It can be captured as shown in code below.
$rootScope.$on('$routeChangeError', function(event, current, previous, rejection){
// Use params in redirection logic.
// event is the routeChangeEvent
// current is the current url
// previous is the previous url
$location.path($rootScope.rootPath);
});
IMO It's generally a good idea to put event tracking code in run block of application. This code run just after the config phase of the application.
App.run(['$routeParams', '$rootScope', '$location', function($routeParams, $rootScope, $location){
$rootScope.rootPath = "my custom path";
// Event to listen to all the routeChangeErrors raised
// by the resolve in config part of application
$rootScope.$on('$routeChangeError', function(event, current, previous, rejection){
// I am redirecting to rootPath I have set above.
$location.path($rootScope.rootPath);
});
}]);
This way we can handle promise failure at the time of config phase.
I have had a complex multi-level sliding panel interface, with disabled screen layer. Creating directive on disable screen layer that would create click event to execute the state like
$state.go('account.stream.social.view');
were producing a flicking effect. history.back() instead of it worked ok, however its not always back in history in my case. SO what I find out is that if I simply create attribute href on my disable screen instead of state.go , worked like a charm.
<a class="disable-screen" back></a>
Directive 'back'
app.directive('back', [ '$rootScope', function($rootScope) {
return {
restrict : 'A',
link : function(scope, element, attrs) {
element.attr('href', $rootScope.previousState.replace(/\./gi, '/'));
}
};
} ]);
app.js I just save previous state
app.run(function($rootScope, $state) {
$rootScope.$on("$stateChangeStart", function(event, toState, toParams, fromState, fromParams) {
$rootScope.previousState = fromState.name;
$rootScope.currentState = toState.name;
});
});
One possible solution might be to use the ng-cloak directive with the element where we are using the models e.g.
<div ng-cloak="">
Value in myModel is: {{myModel}}
</div>
I think this one takes least effort.

Categories

Resources