What issues might I experience in having two different versions of AngularJS loaded into one page?
Obviously this seems like a stupid thing to do, b
Angular 2 will provide a new router with similar features to UI router, but that will also allow to have some routes in Angular 1 and others in Angular 2.
This router is currently being backported to Angular 1, see here a presentation from the developer of the new router explaining how this will work.
The idea behind a common cross-version router with support for both version is to help users upgrade from Angular 1 to Angular 2.
Matt Burke describes a process to wrap the Angular JS libs in a function to create a closure. Downside is that you cannot load Angular via a public CDN as you have customized the download.
http://www.mattburkedev.com/multiple-angular-versions-on-the-same-page/
Angular is really not prepared to co-exist with other version. But it's feasible.
First of all load angular library and make sure that before loading window.angular
is empty:
<script src="vendor/angular/1.2.0/angular.min.js"></script>
<script src="app/app2.js"></script>
<script>
var angular2 = angular;
window.angular = null; // here we're cleaning angular reference
</script>
<script src="vendor/angular/1.0.5/angular.js"></script>
<script src="app/app1.js"></script>
<script>
var angular1 = angular;
</script>
Note that each application (app1.js
, app2.js
) for each version of angular should be loaded immediately after loading angular library.
Each JavaScript file of the application shoud be wrapped in self executing function (function(angular) { ... })(angular)
. Look at the example of app2.js
:
(function(angular) {
angular.module('myApp2', []).
controller('App2Ctrl', function($scope) {
$scope.$watchCollection('[a, b, c]', function() {
console.log(angular.version.full);
});
});
})(angular);
Note that here I'm using $watchCollection
which is only available for angular 1.2.x. By providing scope of anonymous function for each file you are forcing application to reach angular
property instead of window.angular
property.
Finally you have to bootstrap the application using manuall method:
<body>
<div id="myApp1" ng-controller="App1Ctrl">
</div>
<div id="myApp2" ng-controller="App2Ctrl">
</div>
<script>
angular1.bootstrap(document.getElementById('myApp1'), ['myApp1']);
angular2.bootstrap(document.getElementById('myApp2'), ['myApp2']);
</script>
</body>
Working plunker here. After running please check console window to see logged versions of angular used.
Great question! Like you, we were unable to uncover much on this topic...we are in the process of deploying a version of Angular with our product which will be embedded within client websites that could also have Angular already loaded.
Here is what we have done:
If you are going to completely name space AngularJS as I have described here, take care to not do a global search and replace because angular does need a "window" reference for registering events, and a few other places.
I just finished doing this at work and I am in the process of testing. I will update this answer with my results.