remaining elements between url's - angularjs

I'm new to Angular and I'm trying to write an website where some elements maintains between url's. Im not sure what way is the best approach to this. Ideally the clicked elements exists in both urls (partials?) but isn't reloaded but the same element remains after changing url.
I figure that nested views won't work entirely since what I'd like to do is to access the same element from the previous view after changing the url.
thanks!

I agree that the question is too vague for SO, but I'd like to question why you are looking to have the same element persist across pages. Angular is designed with SPA (single-page applications) in mind. Thus, if your requirement is strongest to keep the same html element on the screen after some other action, consider designing your application as one single page, and change everything on the screen around that special div.

Related

Single Page App without URL

I'm joining a team that is currently working on a single page app. It is written with AngularJS, but it doesn't matter for the topic.
The App is so complex (many independant views with complex different states within each) that they completly removed the router (well, excerpt the default route).
I'm googling around but I can see no example of webapp that is not trying to work properly with URLs. Is there any risk of not using any URL, beyond the fact that "it is not the elegant way" ?
EDIT : ui-router does not fit, because of this issue : https://github.com/christopherthielen/ui-router-extras/issues/90
It sounds like you want to look into something like UI-Router which works on states.
https://github.com/angular-ui/ui-router
I can't imagine any significant issues with your app if you do it this way, but I can see massively bloated controllers and code to try and get around any issues you find.
as #Varedis said, you can use ui-router, but to answer your actual question, consider the use case for urls.
If you have only one url, there's only one entry point into your app. This can be annoying if the user expects to be able to quickly go to a certain area (state) within your app. Only one url means that the user can't bookmark, directly go to, or find with a search engine, any specific part of your application.
You can use other mechanisms like cookies or LocalStorage to keep track of state, but these are less user-visible.
I work on the project and i founded a month ago, ui-router-extras which provide parralel states but it can't instiante more than one state instance.
Is there another solution to do that ?

General approach of left side menu that loads different content in a center of the page

I've started to learn AngularJS but I need some application design hints. Of course I'm not asking about the layout but ... how to design my application and it's controllers in a proper way. I have left sidebar with a menu that is loaded from the web using JSON. That needs a controller. That's fine. It works for me. There's a content box as well in a center of my page that loads some data dynamically. In my opinion it requires another controller.
And now comes my solution, that somehow doesn't look good IMHO. When I click a menu item in my sidebar I'm loading a content. Then I'm passing this data into a Service which emits an Event afterwards to the Second controller (which is responsible for controlling my content in a center of my page). When it receives this event it simply gets previously loaded data from the Service and displays it. It generally works.... but ... I'm pretty sure that's not the proper way of doing this.
I would be grateful for any hints. AngularJS has a really poor documentation and tutorial :(
cheers
EDIT:
OK. That's my basic application using JQuery:
http://greatanubis-motoscore.rhcloud.com/index
And that's the same application I'm converting into AngularJS:
http://greatanubis-motoscore.rhcloud.com/angular/index
No worries, some text is in Polish but... I think it really doesn't matter ;)
Note for the AngularJS version: At the moment the content is a HTML but finally it will load JSON data as the other controllers.
I would go about doing this with angular ui-router. With ui-router you can achieve this in a couple of ways. You can use nested routing to have a base state (Your sidebar menu, header etc.) which will act as your shell page, this can have its own controller as well. You could then define each of those other views as child states of the base state. These child states can also have their own controller/views as well, but they will be sitting inside the base state (both visually, and also inherit $scope properties of the base state) optionally they can have separated URLs themselves, but they don't have to, you can just change states without changing the url, by leaving the URL bit empty when you define different states in your $stateProvider configs. Another way would be to use the multiple named views feature.

AngularJS, Deeplinking within a view

Objective
I am currently building my first web application with AngularJS. I need to know the correct way to deeplink to content within a view.
http://signalreview.2mellow.com/ this is the current build.
Description of problem
For example, You can search for mcdonalds, spokane, When this happens I want the address bar to reflect the search that was just done such as #/search/mcdonalds%20spokane so that a user can link a search to someone else. I understand how I can get the data out and initiate the search. I just don't understand how I should be utilizing Angular JS to accomplish the goal.
From my research I have determined that nested views is not a good idea.
Also I have plans to have it so that if you click a map marker for a place that has been reviewed (stored locally in the db) It would put the id in the address bar so that location could then be linked to someone else or you could bookmark it.
Contstraints
The idea is that everything is done on one view with a persistent google map however there are certain states that are saved within that view.
Conclusion
Am I approaching this the wrong way?

Maintaining application state across single page view flips and multi-page flips

Well, as technology progresses, issues we solved long ago crop up again.
Back in the dark ages, when PHP and ASP were considered awesome, we always had a problem with view states. If you had a page with say a dozen select combo boxes on it, your user chooses some combination and hits next, then realizes they screwed up and hit the back button on the browser, the combo boxes would be back in the default state, usually with option[0] selected. In order to prevent this, we had to write boatloads of boilerplate code that would save the state of those combo boxes to a cookie, or session variable, or something so that when the user hits the back button, we can reload the combo boxes back to the state they were in when they left.
This problem was compounded even further if you had a datagrid on the screen. Because then you would have to come up with some slick way of saving that grid somewhere to prevent from having to hit the database again.
Then came the light. Browser developers realized that most web developers were on the verge of going back to writing terminal programs in Cobol due to this issue and added UI caching to the browsers. This allowed us webdevs to not have to worry about this anymore except in odd situations.
So, life was good. Then someone came up with the bright idea of trying to replicate GWT without all the hassle and the web explodes with all these javascript frameworks. The one im dealing with specifically at the moment is AngularJS 1.2.10 with Angular-UI. I have until Friday (most likely wednesday tho) to make an initial assessment on if this technology is a viable alternative to our current standard (thats pretty much universally hated) JSF.
So, i follow some guides, pound my head against the desk a few times, and I have an angular app with 3 actual HTML pages, each HTML page with 2 views.
Before you go there, understand we can't use it unless we can do multi-page JS apps. Some of the applications that this will be worked into have been in development for a decade or more and its simply not financially practical to scrap an the entire UI and start over again. We would instead be doing things like taking these 50 struts pages and converting them to angular/rest and linking them seamlessly back into the remaining 800 struts pages of the application.
So in my exercise of playing with this, I encounter my old nemesis. Back button view state issues.
I have been playing with the UI-route system. The fact that I can deep link using the route system solves part of my problems. But, if say I have a search page like this:
view-search
combo: search type [member,nonmember]
combo: result type [detail,summary]
combo: search state {all the states]
textbox: contract number
etc etc etc
And various combinations of combo box selections and text entries comes up with a list of 1000 people. Now the user selects one of those people on the data grid and it takes you to view-detail. Well the fact that you can use routing to do something like index.html#detail/bob is cool, but if the user realizes thats the wrong bob and hits the back button, they get a blank search screen again and they have to enter everything over and worse yet, send another search to the database to rebuild the datagrid. Some of these screens have 50 or more options to choose from when searching for data so trying to put all of them into the URL routing sounds completely impractical to me.
Now in my research I found this post:
Preserve state with Angular UI-Router
And that has promise mainly because I have a view state object that I can store into a Redis database or a session EJB for cases when the user actually jumps out of angular and into the legacy Struts application, then back buttons back into the angular application, but the fact still remains that on some of these pages, that is a huge amount of boilerplate code that we would have to write in order to make it work.
I don't really mind the idea of having to manually save off the view state object and read it back in from a Redis server or something anytime a user enters or leaves an HTML page in the system. What i'm really looking for is a way to automatically generate the object that is to be saved without having to write volumes of boiler code.
Is this possible? I keep reading the ui-route documentation but it doesn't look like this is addressed, at least not that i've translated yet.
If this is possible, what controls should I be looking at?
thanks
-------------- Edit
I just thought of something. There is one central scope to each of the single page applications. (Im basically going to be building a multiple single page apps and hooking them together) So if i use a naming convention, something like this
$scope.viewstate.view-search.searchType
$scope.viewstate.view-search.resultType
$scope.viewstate.view-search.searchState
Then the viewstate object should simply be a js array and when I create a function to move to struts.do, i can simply save that array off to the Redis server as a nested map object. Then when my user back buttons back into the angular app, i can capture that using the route system and retrieve that viewstate object from Redis and insert it back into my scope, thereby rebuilding the scope for the entire single page app in one shot.
Would that work?
I believe that you have a very complicated issue of trying to keep the view states between your varying pages with the amount of data in your pages. I think that the only real effective way to do this is to write an angular service that you can then pass to your various pages. as You already know the service is a singleton that you can use in various controllers and could be utilized to maintain the view state as you described. here take a look that this link and see if it will help: http://txt.fliglio.com/2013/05/angularjs-state-management-with-ui-router/
After some thought what you suggest in your edit might work, but I would still use a service to retrieve that array of data, as it would make it easier to reinsert in to angular scope
I am exploring something similar for an Angular app that I am writing. Keeping a user login during a page refresh is easy. Displaying the state on the page after a refresh is an entirely different problem.
How long must the state be persisted? I'm evaluating two possibilities.
First, saving the state (current form values or whatever) to the database. As the page changes, incrementally save the state to the database. On a browser refresh check the database for saved values.
Second is to use local browser storage. This is 5 megs of storage. 5 megs is a lot of text. Again this data would incrementally be saved into storage. When the browser refreshed, simply load data from localStorage.

angularjs: tabbed view design issue

[EDIT]
Similar question to Complex nesting of partials and templates
As of now, is it better to use Angular-UI state solution or should I stick with ng-includes ?
So far I had one view per URL in my AngularJS application. I need to build a new view, which should have 3 tabs and I'm having troubles trying to figure out how I'm going to design the view - architecture-wise that is.
Note that the business model object behind these 3 tabs is the same one.
The first tab is for viewing and editing data on the business object. So that's already two 'views' within the first tab.
The second tab is for viewing a paged-table showing data from a child collection of the business object.
The third tab does the same thing as the second one but for another child collection.
Obviously, I do not want to load the entire business object at once. I'll load the collections only if the user navigates to the 2nd or 3rd tabs.
My main concern right now is how am I going to organize the views ? AngularJS has this limitation of only 1-view per page.
Also, I need to handle browser history, so the URL must change when a tab is selected, but I should have to reload any data (i.e I must not reload the controller).
Any tips would be much appreciated.
For the record, I ended up using ui-router and its state management, which is awesome. It took me a bit of time to understand the concepts and to put that in practice, but I managed to build a pretty complex set of layouts effortlessly !

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