Im trying to share data between 2 views. I need to use the 2 views at the same time on two different machines. One is controlling the other(ex: a counter) 1st view has next(+1) and the other just displays the result. I want the data to synchronized/binded. I do not want to have to refresh the 2nd page or to have to pull data with a timer or otherwise.
My idea was to use ng-view and routeProvider, I know that when the view changes the scope is cleared so I tried to use a parent controller/scope, the data is shared but I have to refresh the page on my 2nd view. I tried a service, same thing. I tried to $watch the result of the service but on the second controller/view no event is picked up so the view doesn't update.
what is the way to go? I was thinking about broadcasting or emit a custom event and trying to catch it, will that work? Am I just not binding to the service correctly? Would ui-router work better? I feel there should be an easy way to do this.... Im not seeing it! Please help if you can.
One of the simplest (in my opinion) implementations of client-client communication is using WebSockets. While that does have compatibility limitations (some browsers), that can easily be overcome by using a library like socket.io. Also, it's easy to write an Angular wrapper/service over socket.io that can be shared across components of your app, or even different modules.
It's also pretty simple to write a Node backend with socket.io
This might be a good read.
I would suggest you to focus on pushing stream rather than sharing it. Some how you need to push stream to second view which is changes in first view.
You may want to check this
Is there some way to PUSH data from web server to browser?
Related
My website is built with Angular2. Imagine it as a big dashboard with a lot of modules. Sometimes information from multiple modules are required at the same time - therefore I want to allow my users to open a module in a new window. A real-world example for this is the video container of Hangout.
From my research there would be 2 ways to do this:
I open the route of the selected Ng-Component in a new window. As a result angular would reinit all services. To keep my data consistent I would need find a way to sync the instances. Maybe some kind of service that writes all attributes to localStorage?
This is somehow the way GoldenLayout implemented the Popouts.
I could init my component in window A and hide it - Now open a new window (B) and pass a copy (Css, HTML, Data) of my component to it. This would mean that I only need to sync the mirrored component, but I am not sure if this is good architecture.
Which way would you go to solve the described problem and are there more elegant solutions?
In my Angular SPA, there's some data loaded from the backend that is used throughout the application. This data doesn't change while the app is in use, so to keep things slick for the users I'd like to only load this data once. I can see two possible solutions here:
Load the data when the app is first initialised and attaching it to $rootScope using angular.module.run()
or
The first controller to need the data loads it, and then puts it... somewhere... where everything else can get to it.
Which approach is the "most Angular" way to do this, and how would I start to implement it? Most of the questions on SO seem to be about loading data with the controller rather than when the app itself starts. I'm using 1.4.7 with UI Router if that makes a difference.
You could implement a service which has been sugested by others and ALSO make the service load the data in a lazy way. (Lazy loading pattern described here: https://en.wikipedia.org/wiki/Lazy_loading)
When I first looked at Play and went through all the samples, I was pretty excited by the zentasks sample and the fluid, clean, effortless Javascript routing that left the work of rendering things to Play. But we decided instead to go with Angular.
Upon going down that road, I thought that Angular would control all aspects of rendering.
However, we have a page that has to get a socket. We were having the socket made on the server, so for now, we still have a Play (Scala) template doing that. We have pared it down to pretty much nothing: create the socket and then inject it into the Angular context.
But we are also trying to do Protractor tests and that is made uglier by having to figure out how to accommodate the Scala template.
Question: should we just ditch the scala template and have the Angular controller call the server and get the socket? That was my favored approach to begin with.
I'm currently working on two Play apps with Angular and in both we decided to have one single main.scala.html file that load all the necessary controllers,services,directives, etc from angular using of require.js.
The goal with Angular is to create a single page app and therefore you should avoid to mix it with server side templates.
You must see your main.scala.html template as the entry point of your single page application. There you generate and load all the pieces you need and give the hand to angular to manage the rest.
I agree with Renato. It's probably better to have a single controller and template that sets up the single page app with angular. Then use AJAX to send requests from the browser to other controllers (see http://www.playframework.com/documentation/2.2.x/JavaJsonRequests).
If want to to avoid Scala templates completely, you can put your web pages and javascript in the public directory and only use AJAX.
I have a nontrivial Angular SPA that uses ui-router to manage multiple views, many of which are visible at the same time. I need models to be visible across controllers, so I have services written that allow me to have controllers pull down fresh copies of model data that has been updated.
I apologize in advance for the length of the question, but I will state the problem then state what I have done to address issues I'm sure others in the Angular community have struggled with.
I believe my problem is not understanding the lifecycle of controllers / views, because I get behavior where a controller initializes correctly the first time I go there, but then seems to never run again, even when I navigate to it using something like $state.go("state name").
In one view (contrived example), I show a summary of information about a customer, and in another view I allow a user to update that customer's more detailed profile. I want a user to edit, say, the customer last name in the detailed view, and have the summary view automatically recognize the change and display it.
I have a fiddle that shows 3 views and a simple password changing Service. The flow goes like this:
You can see each view gets initialized and displays the initial password retrieved from the service. All views are in sync with the DataService.
The middle view allows you to enter a new password and change the one stored in the service. Console logging confirms that the service picks up the new password just like you would expect.
(odd behavior #1) When the DataService receives the new password, I would expect the other 2 views (top and bottom) to display the new one. They don't... they still display the initial password.
There is a button to allow a user to go to another state via $state.go("state name") (a child state of the original) which also retrieves the password and displays it. This works the first time (see #5). Now the top view shows the outdated password, the middle view shows the new one, and the bottom one shows the new one as well. This seems normal, since the new view is invoked after the DataService contains a new password value.
(odd behavior #2) If I click back in the middle view and change the password again, and click the button to change states again, the bottom view (which updated just fine in step #4) no longer updates its copy of the password. Now all 3 views show different passwords, even though I am using a single service to pass values between controllers as suggested pretty much everywhere you look for Angular best practices.
Some possible solutions:
Tim Kindberg has an excellent slideshow here that seems to recommend using ui-router's state heirarchy to "pass" data among views that need to pick up values from other views. For a smaller-scale app I think I would settle on this, but I expect our application to have 30+ views displaying data from over 100 REST endpoints. I don't feel comfortable maintaining an application where all the data is being shared by a complex inheiritance tree. Especially using a routing framework that is at version 0.2.8.
I can use events to have controllers listen for changes in the data model. This actually works well. To accommodate performance concerns, I am using $rootScope.emit() and a $scope.$onRootScope('event name') decorator I found on here. With this approach I am less concerned about event performance than I am about wiring this huge app with a bunch of event listeners tying everything together. There is a question about the wisdom of wiring a large app using angular events here.
Using $watch on the value in the DataService? I have not tried this but I am hesitant to hinge an app this size on hundreds of $watches for performances reasons.
A third-party library like bacon.js (or any of a dozen others) that may simplify the event spaghetti, or create observable models that my controllers can watch without the risk of $digestageddon. Of course, if there is a concise way to handle my issue using Angular, I'd prefer not to muddy the app with 3rd party dependencies.
Something that lets controllers actually reference .service modules by reference, so I don't have to depend on tons of event wiring, complex state hierarchies, 3rd party libraries, or seeding the app with hundreds of $watches and then kicking off $digests to update controllers' references to Angular services?
Some solution that relies on time-tested OO and design patterns and not a 3rd-party library or framework that has a version that starts with 0.*.
Thanks in advance... I appreciate the help!
This is no problem of ui.router. If you intend for your model (your data service) to be a single source of truth, you have to refrain from destroying it.. err.. the reference to it that is. And in your case, assigning a primitve (a string) directly to the scope, instead of a reference to it. In other words...
var password = {pw:'initial value'};
and then later setting/binding only on
password.pw = newpassword
{{password.pw}}
Heres a fiddle. And also here is a short little read on scopes, It also includes a video of an angular meetup where Misko talks about "always have(ing) a dot in your model" link and how the $scope is a place to expose your model, not be your model. (aka not a place to assign primitives like password = 'initial value')
Hope this helps!
try remove the animation property of your ion nav view.
remove the property
animation="slide-left-right"
it would be ok.
Basically I'm writing an app and am using Sails, MongoDB and Node JS for the back end. I'll use Sail's API features and was wondering what would be the best way to make the app realtime.
For instance I could use AJAX to call the API and manipulate the DOM using jQuery and update the DB through $.post then let the model update the db in the backend, however I'm finding this approach quite cumbersome. Not to mention I can see the code could become quite difficult to maintain after a while.
I've been doing some research and - if I understood correctly - it seems I could use either Backbone, Angular or Knockout to manipulate the data/DOM on the front end, however I'm not sure what would be the best approach in my case nor whether any of these would indeed suit my needs:
Being able to get the data dynamically
Update the data and the DOM dynamically as the user interact with the page
Post the updated data dynamically with none or as minimal data transformation on the back end as possible
All the above asynchronously
As I don't want this to become a heated debate on which library is best, so I would like to know only whether any of the aforementioned libraries can do what I need and which is the leanest/simplest/has the lighter learning curve.
I did similar research a while ago and when found AngularJS, just stopped looking any further.
Right to your questions:
Being able to get the data dynamically
It is pure pleasure to do it in Angular. For the very basic functionality you have got $http service which allows you to send http request and register a callback when the data arrives.
For more complicated things there are modules ngResource and Restangular (external).
Update the data and the DOM dynamically as the user interact with the page
For manipulating DOM, Angular introduced concept of directive. It is basically future of the web (Shodow DOM and Web Components) right now. At this time point, there is nothing more elegant out there.
Post the updated data dynamically with none or as minimal data transformation on the back end as possible
Yes. JSON.
All the above asynchronously.
Yes, of course.
SailsJS provides interchangeability of HTTP or socket.io connections. In your case I think sockets would be a better fit than AJAX.