How to change stored value in Value recipe of angular - javascript

From the angular documentation, I can see that a value recipe can be used to store some information that can be injected in different modules. So I wanted to use this for storing some user related configurations in my angular app.
What I am doing right now:
Set a value by default-
app.value('display', {
header: true,
switcher: true
})
I have a header and switcher in my views that I want to show or hide based on the value of header and switcher coming from above assignment.
This part of display and hiding works fine. What I want is that if some controller changes the value of header to false, header should then be hidden for that particular user. So from within my controller I just set the values to false. But on page refresh, these values are gone.
I am not sure what is going wrong here. Are we not supposed to change the value? If not, isn't that just a constant. In case we are not supposed to update values, what would be a better way to store some user related variables that will be available to entire app.

First make a factory like
(function() {
"use strict";
angular.module('dataModule',[])
.factory('datafactory',function(){
return {
};
});
})();
Now datafactory can be accessed any where in application just you need to inject this module in required module and factory in required controller
use like this
datafactory.myReusableVar ="something"
later on in someother controller
$scope.myLocalVar =datafactory.myReusableVar
//using session storage
var x ="value"// x can be any data type string,array, or object
sessionStorage.setItem("mySessionItem",x)
$scope.mysessionValue =sessionStorage.getItem("mySessionItem")

The problem is that on page refresh the current context is lost (including all the variables), you should resolve your issue by storing the data inside your browser's localStorge.
check this module
https://github.com/grevory/angular-local-storage

Related

Angular.copy keeps giving me the same object

I have an AngularJS application that manages badges. In the application is a form to set the badge # and the name of the person it is assigned to, etc. This gets stored in $scope.badge.
When the user submits the form, I want to add the new badge to a list of badges, which is displayed below the form.
Partial code looks like this:
var badge = angular.copy($scope.badge); // make a copy so we don't keep adding the same object
$scope.badgeList.push(badge);
The first time I run this code, it adds the badge as expected.
Any subsequent time I run this code, the next badge REPLACES the previous badge in the badgeList. In other words, if I add 5 badges, the badgeList still only has 1 object in it because it just keeps getting replaced.
I'm thinking that this may be happening because the same object keeps getting added? Maybe I'm wrong? I am using angular.copy to try and avoid that happening, but it doesn't seem to be working.
Any thoughts on this?
$scope.badgeList.push(($scope.badge);
console.log($scope.badgeList)
no need to use angular.copy since you are ultimately storing all the badges in an array
angular.copy is used when you want to make a clone of object and not update the existing object and the clone's change are not reflected in main object.
If you just want to maintain a list of badges you can execute this block of code
like this
function addBadges(){
$scope.badgeList.push(($scope.badge);
console.log($scope.badgeList)
}
If you are refreshing the controller then obviously the variable will be reset and for such a case you need to make use of angular services.
Create a service and inside the service you need to define getter and setter method that will help in data persistence
and your bages array if saved in service will persist till the application is in foreground.
You could do something like this.
function addBadges(){
//initialize if undefined or null
if(!$scope.badgeList){
$scope.badgeList = [];
}
//Check if badge does not exists in the list
if ($scope.badgeList.indexOf($scope.badge) === -1) {
//Add to badge list
$scope.badgeList.push($scope.badge);
}
}

Angular 2: Creating a global, settable, observable property?

I've got an Angular 2 app (using v2.1.0) with an authentication service to allow the user to login and logout of the app. I want to create a globally available boolean property that can be set when a user logs in or logs out so I can easily show and hide parts of the UI based on the state of the user. Something like isAuthenticated would be fine. However, I'm not entirely sure what the best method is to create a global class/service, or what the recommended method is. I found this question, which does address it, but all of the answers are from way before the final release came out, and I believe are outdated. Currently I have a property on every component where I need to keep track of the logged in state that goes back to the authentication service, but it seems inefficient to me:
IsAuthenticated: boolean = this.authService.isAuthenticated();
You can try use *ngIf to add or remove element | Visibility to hide or show element
<div *ngIf="IsAuthenticated">Content</div> //add or remove
<div [class.hidden]="!IsAuthenticated">Show with class</div> //show or hide
For more detail
https://angular.io/docs/ts/latest/guide/template-syntax.html#!#ngIf
Add a boolean property to your service and default it to false. When the user logs in set it to true. Create a function in your service to return the boolean. Then just call it like you call your login function.
Services are singletons and do just what you are asking for.
First you need to declare your authService on app.module provider. 1 instance of authService for all your application.
Next you can do that :
<a *ngIf="!authService.isAuthenticated()" [routerLink]="['/login']">Login</a>

How to inject state parameter automatically

Abstract
Hi, I'm using angular + ui-router in my project, I have huge amount of nested states and different views that in turn contain huge amount of different inputs, a user fills these inputs incrementally step by step.
The problem
Sometimes users require additional info that is located on the previous step, and browsers "back" button helps the user to sneak peek into that data, but as soon as the user presses it, the info he already entered is lost due to state transition, which is obviously a bad thing.
Strategy
In order to overcome described problem I have the following plan:
Associate each user's "navigation" (guess this is a proper term) with a random id
To prevent scope-inheritance-and-serialization issues, instead of putting viewmodel into $scope use ordinary javascript object that will be storing immediate values that are bound to UI.
Add watcher to look for changes on that "storage object"
As soon as the change spotted, serialize the object and persist it
Explanations
Why do we need a random parameter in URL?
We don't want to store all data in URL, since there might be quite some amount of data that wont fit into URL. So in order to provide the guarantees the URL won't break, we put only small random GUID/UUID into it that later allows obtaining the data associated with current "navigation" by this random GUID/UUID.
The storage
There are multitude of storage scenarios available out there: LocalStorage, IndexedDB, WebSQL, Session Storage, you name it, but due to their cross-tab, cross-browser, browser-specific nature it would be hard to manipulate and manage all of the data that gets into the storage. The implementation will be buggy / might require server-side support.
So the most elegant storage strategy for this scenario would be storing data in special window.name variable which is capable of storing data in-between requests. So the data is safe until you close your tab.
The Question
On behalf of everything written above, I have the root view called "view" that has a state parameter id (this is the random GUID/UUID)
$stateProvider.state('view', {
url: '/view/{id}',
controller: 'view',
templateUrl: 'views/view.html'
});
All of the other views derive from this view, is there way to make ui-sref directive to automatically inject a random GUID/UUID into id state parameter of my root view, instead of writing each time ui-sref's like:
<a ui-sref="view({id:guid()}).someNestedView({someNestedParam: getParam()})"
I would like to have something like:
<a ui-sref="view.someNestedView({someNestedParam: getParam()})"
The AOP and Decorator pattern are the answer. The comprehensive description could be found here:
Experiment: Decorating Directives by Jesus Rodriguez
Similar solution as described below, could be observed:
Changing the default behavior of $state.go() in ui.router to reload by default
How that would work? There is a link to working example
In this case, we do not solve from which source the random GUID comes from. Let's just have it in runtime:
var guidFromSomeSource = '70F81249-2487-47B8-9ADF-603F796FF999';
Now, we can inject an Decorator like this:
angular
.module('MyApp')
.config(function ($provide) {
$provide.decorator('$state', function ($delegate) {
// let's locally use 'state' name
var state = $delegate;
// let's extend this object with new function
// 'baseGo', which in fact, will keep the reference
// to the original 'go' function
state.baseGo = state.go;
// here comes our new 'go' decoration
var go = function (to, params, options) {
params = params || {};
// only in case of missing 'id'
// append our random/constant 'GUID'
if (angular.isUndefined(params.id)) {
params.id = guidFromSomeSource;
}
// return processing to the 'baseGo' - original
this.baseGo(to, params, options);
};
// assign new 'go', right now decorating the old 'go'
state.go = go;
return $delegate;
});
})
Code should be self explanatory, check it in action here

How to change the same values everywhere - in service , controllers, outside angular?

service implementation
myService = function()
{
this.config = {
show0: false,
show1: true,
role : -1,
id : -1;
};
};
in controller, I map the config values
$scope.config = myService.config; //I guess this by reference, isnt it???
in templates of these controllers for e.g. the $scope.config.show0 is used with for e.g. ng-model
Now outside angular in my threejs code
I get the service using injector which I have defined earlier and change some values depending on certain conditions
var service = window.my.injector.get('myService');
service.config.id = 1991;
Now this value is not immediately reflected in the HTMl template,
Source = {{config.id}} still renders as Source = -1
But when I click on some other button in the same template which is mapped to any other value in the same scope
Source = {{config.id}} still renders as 1991
How should I force this rerendering or refreshing in my non angular code soon after
var service = window.my.injector.get('myService');
service.config.id = 1991;
///do something to refresh that controller
Am I using the service wrong? How should I make this config available in angular controllers, templates and non angular code if not via a service?
Shouldnt changing the $scope.config properties values and changing the values outside angular by retrieving the service via injector change the values everywhere ?
This is because the angular digest cycle does not kick in from your threejs code. I am not sure where your three js code is, but try using $scope.$apply to kick in the digest cycle, and it should work fine.
If you can share a jsFiddle, I can have a better understanding on what you are trying to achieve, but the reason why this is not happening is, as I said, that the digest cycle does not kick in.

angularJs - won't show data until user types in search field

Final Solution? It looks like I had my routing and controllers a little confused. I had my routing in a file with my controller module. I moved my routeProvider into the main module, like in the tutorial example. My controller and my routeProvider where under the same module. Maybe that was confusing everything. So now I have the controller in it's own module, and the routeProvider is under the main module. That seems to have fixed the problem without needing to initialize the search field to force the bindings to update the data.
Update:
The solution to showing my data at the time the page loads was to use an older version of angularJs, or use ng-Init and initialize the search field to a blank space.
I'm getting JSON data from the firebase website to update a table. I have a search field that works. The data will not display in the table until I type something into the search field. I don't know why the data won't just display in the table as soon as the controller is done getting the data.
Note: The link to the backend data is now removed, I don't want to keep that database file there indefinitely.
Here is the link to the jsFiddle code:
Last Version jsFiddle
Here is code for the controller.
'use strict';
/* App Module */
// Create the module named 'testApp'
var testApp = angular.module('theTestApp', [
'ngRoute',
'testServices'
]);
'use strict';
/* Services */
var testServices = angular.module('testServices', []);
testServices.controller('CommonController',
// function($scope, $http, $route) {
function($scope, $http) {
//access the customInput property using $route.current
//var dbKey = $route.current.customInput;
var dbKey = 'test-a-db-12345';
var urlToDb = 'https://' + dbKey + '.firebaseio.com/rows/.json';
$http.get(urlToDb).success(function(data) {
$scope.UsedItems = data;
});
});
How do I get the data to display as soon as it's loaded?
Update 1: I'm assuming that the data is already there, but the event of typing something into the search field triggers the filter, and then the data shows up. It shows up filtered.
Update 2: I'm reading about $Watch There is constantly and event loop listening for events. When a key is pressed in the search box, the bindings {{name}} get updated if something has changed. In this case, the content of the search input field was changed. So the issue seems to have something to do with when the bindings get updated, not whether the data is getting retrieved.
Update 3:
This version of the code runs. It loads the data when the page is rendered. Here is a working example in jsBins.
Update 4:
As of angularJs version 1.2.0 the behavior changes. Versions 1.0.8, 1.0.7 will instantly display my data when the page loads, 1.2.0 will NOT! I just happened to be using jsBins which uses 1.0.7, and it started working. Didn't know why until I started comparing the differences. Hopefully, there is a way to make it work in newer versions.
jsBins Working Example
The problem is that theSearch.Txt is empty. And you are filtering by that. My guess is that Angular at that moment decides to not let anything through and thus doesn't display anything.
What you should do:
Initialize the variable with a space filled string. (i.e. ' ')
Here is a working jsFiddle.
I used ngInit here. But that is because you decided to link?? the controller instead of putting it into a script tag. I suggest that next time you rather take the additional effort into pasting it in, as using the ngInit directive makes me feel like using eval.
Try
$scope.$apply(function(){
$scope.UsedItems=data;
}

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