I'm new to ionic and have been wondering the "angular" way of a "global controller".
In my app, I am using the starter tabs template and I want to have a bar with which I want to interact with as the user lays around in my app. And this bar would be placed in my index.html like the following.
index.html
<ion-nav-view></ion-nav-view>
<div id="my-player" class="idle">
<round-progress background-image="{{roundBg}}" background-repeat="no-repeat" background-position="center" background-size="contain" radius="23" stroke="5"></round-progress>
</div>
I want this div#my-player to be modified as the user plays around with the app.
The initial state for #my-player would be hidden, which I would do so via the css class .idle. But when the user get to my /#/tabs/replay/{:id} page and clicks on an item, I want to add a angularAudioObject and display the audio information in #my-player.
I found it very inefficient to repeat the same code over and over again all of my controllers so I wondered if there was a way to keep this audio-controlling code could be written once and not be called upon in all of my controllers.
P.S. Yes and I'm aware of services and how they could be included in my controllers but I was wondering if there is a way to keep this code "seemingly be integrated onto" my index.html file.
It doesn't really matter which file has the code in it just that the file is loaded and executed. That said you should use services or factories to define objects that you want to persist for the life of the application and for any code that would otherwise be repeated (assuming it isn't something that makes more sense as a filter or directive).
Controllers are ephemeral they are created and destroyed as you navigate views. You can have a controller outside the ui-views that could be a parent of all the other controllers but it's really a fragile way to build things. Instead take advantage of the simple DI.
I would like to know when does it make sense to use multiple controllers on the same page in angularjs. Also, when should one think about separating a controller into multiple controllers?
You should largely have your functionality in providers (services or factories typically) and your controllers should have very little in them aside from getting the providers injected (and exposing models and functions for use in the view) and possibly some view specific functionality (configuration for directives used only in one place etc.). You can have multiple controllers on the page if you decide to build the views within a page to be portable.
If you have one controller that shares the functionality needed for disparate parts of a page and later decide to move one part of the view to another route/state/view then you'll need to piece apart the controller. I don't think there are any hard rules really but if your controller is more than 100 lines you're probably making it responsible for too much and should "promote" some things to be handled by providers and/or start splitting things up a bit more.
The answer would be dependent on your page requirement. Having multiple controllers can easily be done.. But issues pop-up when you wanted to have page flows.
Controllers are just a part of AngularJS.. Usage of services, factories and filters is a recommended way of splitting your code along with controllers. If multiple controllers per page becomes imperative.. try utilizing directives. Also consider using Views provider by UI router.
I use multiple controllers when my page has got multiple pop-ups with complex functionality and i want separate controllers for them so that logic behind each-pop is in its own controller.
Similarly, I create separate controllers for sidebars and header and footers on the same page.
These are few examples which comes in my mind when using multiple controllers on same page makes sense.
But as others have mentioned, you should use providers and services/factory for splitting your code.
I have a site that is developed by multiple developers that has multiple pages. Each "page" initializes angular by calling angular.module(etc).
My question is, all pages share some modules, and some pages use specific modules. What is the best practice to achieve this? Do I trust that developers will insert the correct modules that will be needed across the site (i.e. Google Analytics) or do I create one call that is shared my all pages that loads ALL the modules. And is there a way to do both? Such as, initilize the modules that are needed across all the pages and then, load specific modules dynamically on their respective pages.
I would make one global module that is loaded by each individual app, much like modules like 'ngAnimate' are loaded... the global module could then initialize functionality common to all pages, such as Google analytics.
This requires some policing on all developers involved, but this is a good practice via code reviews, etc.
example page:
angular.module('individualPage', [
'globalModule',
'customPageModule'
]).config(
// etc
);
global module:
angular.module('globalModule', [
'googleAnalytics'
]).config(
// etc
);
I have a site that is developed by multiple developers that has multiple pages. Each "page" initializes angular by calling angular.module(etc).
My question is:
All pages share some modules, and some pages use specific modules. What is the best practice to achieve this?
I do not know the best practice when dealing with multiple pages.
IMHO, creating multiple pages is a BAD practice nowadays. I think of
web applications(SPAs) that have different views and states not web
sites with disjointed pages. So if you choose to go the
SPA(single page application) way, you can load all you core/common
modules before the application bootstraps. Views/pages that need
specific modules can lazy load them using something like
oclazyload.
Do I trust that developers will insert the correct modules that will be needed across the site (i.e. Google Analytics) or do I create one call that is shared my all pages that loads ALL the modules.
I can't say much about the question of trust as I do not know your
developers well enough. In general, developers are never to be
trusted, they will do anything that seems to work, high five
themselves and call it a day. The idea is to "Trust but verify", you
don't have to wire tap their phones or read their emails but never
ever take your eyes off the main git or svn repository. Anywhere, If
you were to use oclazyload as I suggested above for a SPA, you would
only need to worry about dynamically loading 'view/page' specific
modules which the developers can configure themselves.
And is there a way to do both? Such as, initilize the modules that are needed across all the pages and then, load specific modules dynamically on their respective pages.
Yes, yes, there is ... SPA approach that I have already outlined
above. I would also recommend using angular-ui-router for the
states and views approach. The idea is to design your application
whilst thinking of it as a desktop or mobile thick client that has
state transitions and so forth.
I have a site that is developed by multiple developers that has multiple pages.
Each "page" initialises angular by calling angular.module(etc).
My question is, all pages share some modules, and some pages use specific modules.
What is the best practice to achieve this?
Do I trust that developers will insert the correct modules that will be needed across the site (i.e. Google Analytics)
or do I create one call that is shared my all pages that loads ALL the modules.
And is there a way to do both?
Such as, initialise the modules that are needed across all the pages and then, load specific modules dynamically on their respective pages.
I would start off by defining what a page is.
Are you talking about a SPA or a more traditional setup a la client transitions between pages with a regular <a href="/page"> and
the server serves the client a piece of HTML?
If the latter is true, then I would urge you to reconsider your underlying approach to your Angular application.
The best (or rather, preferred) way of doing things would be to serve the client a single piece of HTML, and then
transition between pages (from now on I will refer to them as states), by using either ngRoute, angular router (2), or
better yet - ui-router.
For the remainder of my answer I am going to assume that you are in fact working with a SPA.
What is the best practice to achieve this?
As it stands, I would go out on a limb and say that there is no best practice defined for the case you present.
There are a ton of ways to do it, none of which have been officially recommended by the core development team / community standard as far as I'm concerned.
You could go with webpack-angularjs-lazyload, requirejs (angular-requirejs-seed), requirejs (angularAMD), SystemJS among others. Pick your poison of preference!
Do I trust that developers will insert the correct modules that will be needed across the site (i.e. Google Analytics)
or do I create one call that is shared my all pages that loads ALL the modules.
If code contained in an angular.module is required across the site, I would attach it to the main application module.
Such as:
/** Define core functionality that _is_ essential to the application running as expected **/
angular.module('core-module', [ 'route-definitions', 'http-interceptors', 'google-analytics' ]);
/** Inject the core functionality into a bundle module **/
angular.module('main-bundle-module', [ 'core-module' ]);
/** Bootstrap the bundle module as your application **/
angular.bootstrap(/* DOM element */, ['main-bundle-module']);
Now, whenever someone creates a new module for a specific state, they will need to inject said module into the main-bundle-module (barring lazy loaded modules).
As such, the core functionality will always be supplied and available, in your case Google Analytics. In a sense, you just tore down
the trust barrier.
Taking a step back, lets for a moment assume that you are not working with a SPA - and you are in fact re-initialising the
angular application on each page transition (bad move). How would you ensure that the required functionality is always present?
Decorating the angular.module method.
Note: This is not officially supported, be wary of what you are doing. Also it defeats the purpose of modularisation in my opinion, but I'll
showcase the way(s) of doing it.
You could go two ways here I reckon:
Kill the execution of JS if the required module is not a part of the developers module definition.
"Bad cop."
This would catch the 'untrusted developer' in his/her tracks during development, so as to ensure they are following the project standard.
Assist the 'untrusted developer' by automating the task of requiring the module.
"Good cop." (well, sort of...)
This would ensure that the required module is always present, albeit in every module.
"Good Cop"
(function(angular) {
// The always required module(s).
var ALWAYS_REQUIRED = ['cs.core'];
// Keep a reference to the original angular.module function.
var originalFn = angular.module;
// Keep track of registered modules.
var registered = {};
angular.module = function (name, dependencies, configFunction) {
var loaded;
// Ensure that we are always working with an array of dependencies.
dependencies = dependencies || [];
// If the module has not already been registered
if (!registered[name]) {
// Ensure that the required modules are available.
ALWAYS_REQUIRED.forEach(function (required) {
if (dependencies.indexOf(required) === -1) {
dependencies.push(required);
}
});
// Register the module and store it in the registered object for future reference.
loaded = registered[name] = original(name, dependencies, configFunction);
} else {
// Do not re-register the module, simply load it as per 'angular.module('name_of_module')';
loaded = original(name);
}
// Return the loaded module.
return loaded;
};
})(angular);
"Bad Cop"
(function(angular) {
var ALWAYS_REQUIRED = ['cs.core'];
var originalFn = angular.module;
angular.module = function (name, dependencies, configFunction) {
ALWAYS_REQUIRED.forEach(function (required) {
if (dependencies.indexOf(required) === -1) {
throw new Error('You need to add ' + required + ' to ' + name + '\'s module dependencies!');
}
});
return originalFn(name, dependencies, configFunction);
};
})(angular);
That's two ways of killing the trust issue, but in doing so we've introduced code that;
Is not very pretty.
Is definitely not very well tested / battle proven.
Kills modularisation to boot.
And is there a way to do both?
Such as, initialise the modules that are needed across all the pages and then, load specific modules dynamically on their respective pages.
I would say the best way to do so is to:
Take the steps necessary to convert to a SPA.
Write some documentation for all your developers so as to bring them up to speed on the requirements of the project.
Create a standalone module containing the required core functionality and attach it to your ng-app/angular.bootstrap module.
Get ui-router, ui-router-extras and ocLazyLoad to allow for lazy loaded module/state/component definitions.
Have a look at some of the following links for inspiration/ideas on what fits your specific project:
ocLazyLoad-SystemJS-Router by #lookfirst
ng-jspm-seed#futureStateConfig by #kasperlewau
ocLazyLoad#with-your-router
ocLazyLoad+requirejs plunker
webpack vs browserify #stackoverflow
angular + webpack slides
tl;dr
Convert to a SPA.
Bootstrap the application with core functionality supplied.
Write some documentation for untrusted developers.
Better yet, build trust. :)
Lazy load state-specific modules when needed.
You can try browserify to load and build your javascript in single file.
With this you can easy minify the javascript code, and also you can load nodejs modules like events and more, but this is not your question about.
I am building a large application with Web API and AngularJs. I built the secure web api with authentication and claim-based authorizations. One requirement is that different users can view different modules on the same template.
I am new to AngularJs. I did the authentication in client side with the tokens. Also, in web api, I created a service to get all the permission given a user id. The response is a list of resource(contoller)/action(method) pairs. How do I implement the correct layout based on authorization rules on client side? Does that solely rely on web api permissions response and show/hide (ng-hide/ng-show) content based on the permissions?
Is this a good approach? What other modules/directives do I need to look into? Such as the loader for not loading the nested route until user request the parent route.
To add complexity, this site also need to work in bi-lingual. I think ng-translate. I mentioned this because it may open up another discussion on whether this may favor MVC instead of AngularJs. But the preference is Angular if the above two problem can be resolved.
All the authentication & authorisation & validation should be done server-side. You can adjust the user interface based on the roles/claims the server tells the browser the current user has.
One way to do this is to create something like a roles/userprofile controller, which will respond with a list of roles the current user has. On the client side you’ll probably want something you can inject everywhere, so you’re able to determine user interface behaviour.
myApp.factory(‘myUser’, function(Roles, $q) {
// Create a promise to inform other folks when we’re done.
var defer = $q.defer();
// For this example I’m using ngResource
Role.query({
/*
No params — let the server figure out who you ‘really’ are.
Depending on WebApi configuration this might just be
as simple as this.User (in context of the controller).
*/
}, function(roles) {
var user = {
roles: roles,
isInRole: function(role) {
return user.roles.indexOf(role) !== -1;
}
};
defer.resolve(user);
});
return defer;
});
Because the factory above is returning a promise we can enforce that myUser is resolved before a certain route/controller instance is created. One little trick I use is to gather all my route definitions in one object, loop through them with an angular.forEach and add a resolve.myUser property to each of them. You can use this to pre-load/initialize other stuff too.
Now inject the myUser anywhere you like:
myApp.controller(‘MyController’, function($scope, myUser) {
// Expose it on the current scope
$scope.myUser = myUser;
});
… and in your markup …
<div class=“my-content-thingy”>
<p>Lorem del ipsum …</p>
<button class=“btn” ng-if=“myUser.isInRole(‘content-editor’)”></button>
</div>
Note: You’ll probably want to use ng-if and not ng-show; the latter keeps the element in the DOM.
Just keep in mind that you don’t authenticate anything on the client side; that all done server side. A simple way is to place Authorize attributes on the appropriate controller actions.
Hope this helps.
A proper approach is to build AngularJS routing configuration as per Authorization on the server. This should be build just after the user is authorized and before the AngularJS app is initialized. That way the authorized user sees a "complete" app based on his roles etc. Using ng-show/ng-hide is not a good way to do it. Also each view should be doing only one thing. So load separate views based on the task that needs to be completed.
Regarding multi language support, this is independent of Authorization. Some time ago, I wrote a custom AngularJS filter that used the jQuery i18next plugin. It was a pretty simple implementation.
However you can now use https://github.com/i18next/ng-i18next
(Sorry for misunderstanding the problem).
I think that using ng-hide/show is not much of a problem. At the end of the day, the user does not have access to the data. I think it should rely on the api permissions + show/hide of presentation. Depends on the complexity you want... You can use MVC with angularjs since it's a large application.
I am working on a small piece of an angular project and need to define some constants that are derived from values in a database. I have a REST endpoint that delivers the data I need, but I can't figure out how to load the values before the app gets automatically bootstrapped.
I cannot modify the application to a manual-bootstrapping process. Typically a resolve would be used upon navigation, but I have other components (like modals) that use the constants that aren't necessarily part of any route.
What would be ideal would be some sort of "resolve", but at the application layer. I do have the ability to load npm and bower packages, but anything that changes to a 'manual' bootstrapping method isn't allowed.
In that case I can recommend you to use a $rootScope. I don't understand very well your needs, but everything that is stored in $rootScope will be available in all views. Just fill it with your REST service inside the first or main view of your app. Although, it is important to understand that if you refresh you page, the $rootScope will be as well refreshed, this is, all of your REST calls will be launched again. (Navigating inside angular views is NOT refreshing the page unless you ask for it using window.reload() or similar; it is just the same page with a new controller)
To avoid this last behavior (page refresh) you could also use local Storage, which is basically a small amount of memory inside your browser where you can save any data that you want to keep regardless of your page refreshes. I used in one of my projects this library: https://github.com/grevory/angular-local-storage
It was useful for saving permanent stuff until user logs out.
Hope it helps! And sorry if I am answering something not useful for you
Cheers
It seems that the only way to effectively load some values from a service prior to the app starting is to make the service-call to and then manually bootstrap the app. The idea of an app-wide "resolve" doesn't seem to exist.