I'm building a wizard-config app with 3 pages. Each page has the same MasterController but different html templates. Each html templates has a different controller, say ControllerOne, ControllerTwo, and ControllerThree.
I load the data via MasterController and I'd like the data and any changes the user makes to be stored temporarily until the save & finish step on the final page. Trouble is as the user goes through the pages, MasterController is called each time and each time it fetches the data and overwrites the user's changes.
I've thought about attaching this data to a service or rootScope but the data initialization still happens in MasterController so the data would still be overwritten when each view is loaded.
Any advice on how I should go creating this functionality or restructuring my app to support this?
EDIT:
To be clear on the service issue. I don't know where to initialize it. If I do it in Controllers 1,2 or 3 my data is reinitialized each time the view changes so that doesn't work. I can't do it in app.run() either because I need to get to MasterController in order to get the necessary ID to make my HTTP request. I can't do it in MasterController because that too is called on each page switch.
Ideally I'd have a view within a view so that only the inner view changes. However angular does not support nested views and I'm trying to find a way around this without having to use angularUI.
To get around the data being loaded from the server on each page change and overwriting the user data, I used an "extend" function (like jQuery's) to extend the server data with the user data on each load. Page changes would call my service(that stores the temporary data) to save the data there and the final "save and finish" button would push the data in the service to the server.
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I have a single page angularJS / nodejs / express app. When first loading the app, it pulls data via API from database and displays in a table in the 'home' route. 5 minutes later, it updates the data by doing the API call again then $scope.$apply().
After the update if I navigate away from the 'home' route to a different view within the app, then back again, you can see the old data for a fraction of a second then the new data pops into place again.
This will happen repeatedly as I navigate away and back to the route.
It seem like the browser is saving the old data, then updating it every time I go back.
Why is this happening and how can I make the $scope.apply changes permanent?
The solution was to load the data into an object in a factory, and update the data object in the factory instead of in the controller. This keeps the data up to date when changing views.
Have 2 pages for one long process. Both in one controller. My problem is:
In first page, using angular - run method that generate some data. Store that data in property in controller. Move to another page, using angular - run another method and that is... my data in property is null. Is there a solution to store data in controller properties in thid situation?
New instance of a controller is created on every request so whatever you save in property of your controller this will be destroyed together with a controller when request is ended. You have to store this data either on client(cookie, local storage) or server side (session, cache, database etc.).
With ASP.Net MVC, you can't store data in a property between 2 actions.
For achieving this, you have to use cache strategy.
Please, see this link.
I have 3 JSP views which all use the same JS file(say app.js).
My UI is on AngularJS which has a different controller for each of the JSP views and also has a custom service which shares information between the controllers. When I load the first JSP, its controller specified in the app.js file saves a value in the custom service. When I load the next JSP file, app.js gets reloaded and so the value that was saved in the custom service is lost.
Is there a way to not re-load JS files? Or is there a better way to go about this?
If you have no control on the server , you can save the data in browser's session storage object to keep data across requests and clean it, when you are done. https://developer.mozilla.org/en/docs/Web/API/Window/sessionStorage
// Save data to sessionStorage
sessionStorage.setItem('key', 'value');
// Get saved data from sessionStorage
var data = sessionStorage.getItem('key');
// Remove saved data from sessionStorage
sessionStorage.removeItem('key')
Javascript variable are not automatically preserved. When you open a new URL in your browser, you do not download again the JS files (they are cached), but they are loaded from scratch in that new page. That means that all previous values are lost, not by accident but by design.
You have different ways to deal with this persistence between page question. One way is server side by using the session:
the js part sends the value to save as parameters of a request
a spring-mvc controller puts that in the session
other views (jsp) or controllers (spring) access the saved value and pass it in the responses
An alternate way is the single page application pattern:
you only load one single full page from the server
the javascript then only sends requests that it processes directly to modify the DOM
Additionally, you could use Windows.sessionStorage to store data client side for the duration of a client session - credits should go to #AmitParashar for this one, more details in his answer.
You can of course mix the 2 patterns (this is commonly done in real world applications), but you must know that every page load will erase all client javascript state
A less common pattern (AFAIK) is to put the state in a cookie. That way it can be shared by the server and the client but:
it is limited to 4k size
you cannot use it for server side security, because it can too easily be forged
The problem:
AngularJS forces to split view from model and it's good. But we're experiencing the following downsides because of it: When a user loads our page a browser makes not 1, but 2 requests:
First it loads view template (the first request)
Then Angular services load data from a server (the second request)
And we have a bit slower load page speed.
The question:
Is it possible after first page loading load view with populated data and only then get data from a server when something must be changed on the page?
I tried to find something regarding it, but didn't find anything.
You will have a lot more request as you have to load the Javascript and CSS libraries as well.
You can store your initial data in a service or the rootscope and just update the data when you need it. What's exactly your problem here?
The modular approach would be to break all the different components of the page that consume data into separate data requests, so that the interface can load in progressively as different data requests complete.
Additionally, you can load initial data, but then make some predictions on what the user will do next and lazy load additional data in the background.
Finally, you could store the previously loaded data in local storage (lots of modules out there you can utilize) so that it's pulled instantly upon the user's next visit. You would want to want to also add some sort of timestamp comparison on data in storage and on server to see if it has been updated.
I'm making a totally local Backbone app, no server-side included, and I provide the app with some initial local data. The data is actually the Collection data which is a json file and stored in a folder called data. So I provide the Collection with a url attribute which is data/datalist.json and use this.collection.fetch() to get the inital data. All works well.
But I want any update happens in View would save changes to the corresponding Model data in this Collection json data file. It seems that this.model.save({name: newName}) doesn't work for me. Every time I refresh the whole page, the app will still show the inital data file. So how should I change the data file when a item in View is updated, deleted or created? Do I need to set a url attribute in Model?
Model.save calls the Backbone.sync method, which by default maps CRUD functions to a REST api. If you want to use something other than REST for save/update/delete, then you need to override Backbone.sync.
There is a local storage plugin that overrides sync on Github, which is endorsed by Backbonejs: Backbone.localStorage
This plugin should persist your data while the app is running. You may need to extend it if you want to write changes to your filesystem (not sure, haven't used it myself). Hopefully this gets you started.