Angular service variable not updating The OnChanges listener is for listening to changes done outside angular (like a library). Then in my view main. So you need to always get the current station from the service instead of caching it in the I have a problem where my view will not change when I update my variable in my observable subscription. Angular will not re-render the *ngFor block, until it detects changes in the menu. Nov 23, 2016 · Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. controller('mainController', [ function() { var Dec 28, 2015 · As you can see i have a variable named test2 and in the constructor i set a timeout of 500 ms where i am updating the value to "updated text". It wouldn’t reflect the changes until function done execution. Angularjs service variables not updating properly. Jan 18, 2022 · The default way that Angular tracks changes is by reference. Mar 28, 2018 · The console. 0. The issue was the initialisation of isLTEavailable variable inside the ngOnInit which resulted it in being updated back to the original state whenever the function was called. ts providers, NOT individually in each component. Variable only gets updated after second call (basically click the search button twice to update it May 16, 2015 · AngularJS Update Service Variable Not Working. A solution would be May 22, 2022 · Finally in my list-item component, I subscribe to service. Mar 20, 2020 · import {Component, OnChanges, SimpleChanges, Input} from '@angular/core'; class Child implements OnInit, OnChanges { @Input() Data: any; // here is the data variable which we are getting from the parent constructor() {} ngOnChanges(changes: SimpleChanges) { console. So, you cannot directly use primitive values, use reference values. However, It appears that ngStyle is only evaluating on first render, and not updating when the property of the component changes. If you only need to watch a service property/variable, an object is not required -- a primitive can be used. The only way to see changes is by clicking the button. My problem is that the parent's variable is actually getting updated in another child's component that is inherited from the parent. module. angularjs set and get a value from a service. To do this i used the method of Creating a Global variable and subscribe to it ( Subscribe from Navbar) location. Mar 2, 2016 · The UI is displaying variables a, b, and c. Variable in component gets updated only after second function call in service in angular 4. ? Thanks in advance Oct 16, 2019 · Perhaps I have the wrong setup from the beginning, but I'm having an issue with a child component @Input decorator not updating after the parent's variable has changed. Sub View Component May 20, 2018 · I want to update a variable that is inside a service in Angular. The problem is that yu expect the validate method to be called again even though the form control value hasn't changed. isUpdatingSubject. If I then trigger an update manually (by clicking some unrelated button that updates the UI), b and c are Apr 30, 2023 · Declaring a model value in the template, then passing it as a reference in method params, does not detect the updated model value; We are going to discuss this issue in detail and also the ways to resolve it with a simple use-case. slice() or something like that to change the memory variable and trigger the change. . Dec 20, 2020 · I have an angular application in which, there is a service having 3 types of variables: simple boolean, behaviorSubject of type boolean and an Object with the property of type number. The asynchronous call in your example does not qualify for this. May 26, 2019 · Getting issues with the view not recognizing value changes on a component I've tried using ChangeDetectorRef and still not getting any results. The service is shared across two components that also use element_id: nav. I tried following stackoverflow posts - Angular 2 View will not update after variable change in subscribe; Angular 6 View is not updated after changing a variable within subscribe; Following is the code what I am trying Feb 7, 2016 · angularJS, UI is not updating. So, you cannot access them from your controller. Ask Question Problem is you are assigning an undefined variable not scope variable. After doing a bit more research and finding this page: Angular 2 - View not updating after model changes. ts is my global variable service I had very similar but even weirder problem where I was updating one of my scope variables using the response from an HTTP call, surprisingly, my view will not update unless I make another HTTP call and by another I mean any other random HTTP call. Mar 1, 2020 · Two things of note in the service: A variable, element_id, is declared, but not given any value; The last function, change_val(element_id), changes the value of element_id when it is run. There are many possibilities as to why "nothing happens" when a variable is "updated". Here I propose another solution but I'm not sure if it fits with your application. You will not see the changes. If you use primitive values they will be local to ng-if scope. I found the issue with my code and fixed it and now the interpolation works as expected. You want to have a singleton service, so only set the service in your providers array in your Worked for me. Jul 31, 2021 · Angular may not update the view automatically (depending on change detection strategy). c1Var = service. Jun 24, 2020 · First, you need to understand how template/html rendering in Angular works. I have a login controller that talks to a service to get a user logged in. When the underlying reference doesn't change, Angular won't detect it's changes. Please have a look at basic types of reactivity provided by angular. From this and this, my understanding is as long as changes to variables are within Angular, there is no n Nov 20, 2018 · It would have automatically updated if these service variables were of a complex type like an Object or an Array as these are reference types. tried a bunch of thing and iv'e spent way to much tim May 9, 2014 · That solution above is just to point out your problem. Viewed 1k times 1 I have the following service Dec 3, 2016 · Note: Also, please don't use $ prefix to service, variable, controller names as this is reserved to AngularJS and may create conflicts when you use the same name as AngularJS reservered keywords/services. Modified 10 years, 3 months ago. I'm trying to update the option labels of a select box based on the value of another. Every thing is going good, I have changed value in ngOnInit of App. Feb 8, 2014 · When you return loggedIn at the end of your service, what you're really returning is a copy of the variable. Aug 25, 2015 · When your controller is constructed, it asks the current station to the service and stores it in a scope variable. getSomeVar()` you storing a reference to `service. sorular = soruLst; } That said, when you do this: `this. Reply reply Ynot_reddit Sep 25, 2012 · @JimmyKane, yes, primitives should not be used for 2-way databinding, but I think the question was about watching service variables, not setting up 2-way binding. A way to ask Angular to render the view is to inject ChangeDetectorRef and call this. Here is the code for my component Jan 6, 2014 · The data gets pumped in and as far as I was aware because its being stored in Service. In it I try to assign a regular variable one of the values of the observable variable. Try Teams for free Explore Teams Dec 9, 2019 · The problem is not the new value s not received. I have a subscribe method on it to listen to updates. ts. AngularJS: Service vs provider vs factory. In *. The following code should explain this more clear. For example, when the user enters my site, they are brought to the About page. Sep 19, 2022 · The view wont update until for instance I click on a button! (any button in the app). someVar`, but not changing the `this. Mar 3, 2020 · api. For the global variable access, I created a service and injected it into my component pages. I am trying to make it so when a request is made using one component, it increases a count variable in the service. If so tell your component's view to update: inject the ChangeDetectorRef via your constructor: import { ChangeDetectorRef } from '@angular/core'; Mar 1, 2020 · Upon inspection, one can see the shared variable element_id is established with no value in the service and is supposed to update when a user clicks on each button in the view. That did not work. This works on page reload, but I want it to update the list after an item is added without refreshing. variable only it's contents are changed. This is Service import { Injectable } from '@angular/co Aug 11, 2017 · I am not sure what your problem is, but if it some data in your service that you would like to share with other components you can do the following. My question is why the view doesn't update when the service value is updated as expected? Jul 7, 2019 · Angular not updating Ng-class when on-change is triggered 0 Angular 2 change detection, ngClass model gets updated by sibling component but the template does't get refreshed Mar 21, 2019 · child. log response but this. asObservable(); setUpdateState = (newState) => { this. ts Mar 13, 2013 · I have a NavbarCtrl that is outside of ng-view. Instead the scope value must point to the object that wraps the changing data. Jul 21, 2017 · Since you mentioned that you already tried markForCheck(), you should try detectChanges instead (that just what worked for me and markForCheck did not work). Apr 14, 2014 · Angular service variables not updating. You may have to change the design such that you return observables from your service. next(newState); } Aug 16, 2018 · The service contains methods to interact with my REST backend. This isn't working (changing the variable via the header doesn't update the variable in the content). As a simple test, have an infinite loop and update background color of an element before entering the loop. The data is successfully retrieved within service however it does not update the variable associated with component (waittime) immediately. This is the code in the GlobaldataService: Aug 1, 2018 · I am probably overseeing something, but I am stuck, the following variables do not seem to be updating in the template when their values are updated in the promise: private emailDetected: boolean = Nov 22, 2020 · The call to the component recognizes the first two parameters, but does not update the variable (in the example, inputMotor), always keeping its value as 'none', and not displaying the field for "Other". in Service, update 'sorular', in 'updateSoruLst' (Fail - it's not changing, only changing in function scope but i still can't read updated value) . Jun 16, 2018 · Here I am subscribing notification$ of Notification service in App. I don't know your application design, you may not follow this solution but restructure your code to best fit your application design (like storing the employees in a shared service,). As in your case, since you are rendering your menu link list from an array, menu. dataObj. Not the new one. waypoints = waypoints; I'm starting lo learn about Angular. The show value is changed to true, but the view seems to not update. I tried it like your example - subscribing to the http call right in the service and setting the value of the BehaviorSubject there. The first is to use setters and getters for the playing variable. Component. When I call clickme() the value of variable name doesn't update on the webpage and shows old value "no name". module('appName',[]). changeDetectorRef. mainImageUrl, the image is not updating. ts: This service contains 3 shared functions: 1 (getMenus) for getting the menu content from an API call, a second (getData) for getting data from the same API call and a third (change_val) that is called from the menu items in another component and changes the value of the shared variable (element_id) when each menu item is clicked. So you end up with a reference to a different component than the one Angular is actually using to display your recipe. Jan 29, 2021 · Update: close open subscription. service. But when you update the current station in the service, the scope variable still references the initial current station. js and I have created this controller for my app: angular. In the Angular app, we need to make changes in local variables which are getting used and defined as global. I'm trying to create an angular app to drop markers on a map. Angular 2/4 has built in data-binding, meaning that if you use your service in your components as public, you can manipulate the objects directly, and all other components will have the updated Sep 2, 2015 · Ask questions, find answers and collaborate at work with Stack Overflow for Teams. admin. It's not enough to push data onto the array. I want to update the variable with the input form when i click the button. Sep 16, 2016 · I've got a problem with angular, A portion of my variable are not updating after changing their values. Feb 19, 2019 · confirm for me how you're injecting the service. May 19, 2021 · You need 2-way-data-binding. projects = this. OnPush? This option decouples Angular from auto updating your view. What am I doing wrong here? NOTE: I actually wanted to test if the subscriptions in the component are working as expected or not! REASON: I would like to check-in further tests that when the value in service is updated, does the DOM changes automatically or not Jul 30, 2018 · I am new to angular and trying to update variable but I variable is not updating in view. When the changed event is raised by the thing service, variable a is correctly displayed as 1, but b and c do not update in the UI. Now, what you can do is something like this, BUT for updating the changed service data in the scope correctly, it is important that the scope value of the controller that uses the service data does not point directly to the changing data (field). But that's not how Angular does data binding - it creates the component for you. Once the user is logged in, I want the Navbar to update with the user's em As far as I know, Angular is only updating the view, if you change data in the "Angular zone". Dec 11, 2018 · I have multiple components (in an NgFor loop) that call the same service. I'll explain my code: So I have a Service, a Base Component, an App Component & another Component Mar 31, 2021 · This property is indeed changing, as other parts of this component are reliant on it, and functioning as expected. My goal is to have a service that contains the relevant variables and functions that animate a page when navigating to a certain path. You enter a descr Mar 12, 2019 · Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand OverflowAI GenAI features for Teams OverflowAPI Train & fine-tune LLMs Jan 10, 2018 · Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Select code for Feb 17, 2021 · Angular 6 - Variable in service not updating. Every time I upload this. ts May 14, 2017 · @Scipion In general, if you subscribe imperatively you should unsibscribe imperatively as well. The code looks like this. The same behavior persisted after doing this, with no change detection being triggered. But since you have Service variables of type number and boolean, these will not be updated automatically as they are primitive types and hence passed by value. component) initiates a GET request. In your case, just pushing the same variable will not trigget the change detection. d if I point my HTML template at Service. c1Var` reference, so the view is not updated. I am accessing a variable "name" created in service and updating it but it isn't working. ts Mar 27, 2018 · @JasonK - Then you must be clairvoyant. So the tests fail because the "book" variable does not update with the new values. For those that need the steps: Add ChangeDetectorRef to your imports: import { Component, OnInit, ChangeDetectorRef } from '@angular/core'; Add ChangeDetectorRef to your constructor: Aug 15, 2019 · I Have a Navigation Bar that is global For all the Modules in my Application. How to update scope variable using service. getItems() and set a local variable which is used to update my view. For varExample you reassign it's value this. component can't get a new variable from service. When you click the map, a function generates the marker and opens a form and then another function logs the position. Ask Question Asked 10 years, 3 months ago. So when you later update it inside of UserService, the copy won't get updated. Here are some code : May 29, 2017 · AngularJS - Controller variable not updating from a service function 1 angular - I have an element in the view bound to a variable in a service, but the view is not getting updated when the service is updated Jan 23, 2021 · Here is a simplified example that does a very similar job without a real backend. Apr 13, 2017 · A question that has been asked (and answered) a thousand times, yet I can't figure this out. instead what you need is to write a getter for email property and return value calculated based on displayName Jan 30, 2018 · I have been doing a bit of research and decided to give this example a try: Pushing Real-Time Data to an Angular Service using Web Sockets. How to set and get a value in a service - angularjs. Dec 10, 2019 · Did you use ChangedetectionStrategy. dataObj that object is being updated and not replaced so the pointer should remain and the object be watched. Update scope value when service data changes. unsubscribe() on it or use takeUntil(). Functions always play a vital role as part of change detector so it ensures that your change in variable reflects. Dec 29, 2018 · Function called via service(app. How to fix that? Nov 23, 2021 · Angular service variables not updating. updateInterimResults(s) does not update the template. If you are not listing the service as a provider in the module (but only injecting it into the component constructors), then you have 2 separate instances of the service. Dec 19, 2019 · Thanks all for having a healthy discussion here. log I have in the subscribe logs that this change took place, however, the icons in Component1 HTML never update. Its being defined in the service because it is used in other components. You have to set the array to a new array, change the default change detection strategy, or manually tell Angular to detect changes. When it is necessary to obtain a data from a simulated server, edit a hero’s name and return to the previous page, my hero continues to display the same name on that page. But I obviously don't want to put a hidden button to trigger changes. log(variable) although it is not updating in my View using {{ variable }} I have tried several things, my last option was to use Observers and still not working as it should. mainImageUrl it is getting the updated value but it is not reflecting in the html. But when i go to specific component i want to hide the search bar from my Navbar. someVar` When you call `service. I hope that makes sense. Aug 3, 2017 · Can't really tell why its not working without looking at the code. than parent. The header calls a behaviorsubject service to set a variable, and the content component displays the variable. 1st step: add to the html tag <my-lib [(query)]="query"></my-lib> 2nd step: add an EventEmitter to notify the change back, the name is important, must be the input name concatinated with Change, so in your case queryChange. My header updates just fine my footer only stays with their initial values. Modified 9 years, 4 months ago. ts but its view not rendering/updating Aug 18, 2018 · Your changes will not reflect on UI while your script is running. log(changes); // here you will get the data from parent once the input param is Jan 10, 2020 · While the variable is getting changed (I validated the change by logging it to the console), it does not seem to trigger a UI refresh. But this is another example why I have the feeling angular framework developers are lost in the complexity of the angular framework. push(); this. You have only 2 scope levels: the controller and the ng-repeat childs; and you are updating the list in the same scope (the controller's one) that the one you used to instantiate it. Terrrible!! – Jul 29, 2020 · Angular will not detect the changes if you don't change the "in memory" variable. But for this. admin array. The filter service Jan 20, 2018 · Reason is that displayName property is used to initialize email property value, hence consecutive reads of email property returns same value, no matter displayName is changed or not. To resolve this I need to reload the page or navigate to another page and return so that the method for updating the variables is Jan 4, 2018 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand Apr 5, 2021 · An Ionic 4 project: A parent component contains a header component and a content component. component get a new variable from service. If you used a setter or an ngOnCHanges, you could easily chck that. Nov 8, 2018 · If you are simply pushing object or data into an array, angular wont detect it as changed property (which is bad). html i simply use: {{ test2 }} But the value will never be set to "updated text" and stays on "initial text" forever even though the update part is being hit. To inject a singleton instance into the components, the service needs to be in the provider array at the module level. I console log it to see if it has been updated and it has but the value is not updated in the template. – Oct 8, 2016 · ng-if creates a new scope. I tried as suggested in this post, but it worked fine only for a single variable (it's not reusable). May 17, 2019 · I have an observable variable that gets its value from the store. const waypoints = [this. And for the example above, you can have as many component you want to share the service, its the same way, you inject the service and use the get and set methods. The solution I found was to make a method that returned a function scoped variable: Jul 19, 2018 · Whenever you add new user, the components will not be notified about new value as change detection of Angular will not kick in for the copy of array stored in components. But if you want, you can put it in the Angular zone or use rxjs or extract part of the code to a new component to solve this problem. I am trying to show a loading spinner while I wait for a response from my backend and then di When you call `service. Sep 7, 2015 · Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand; AngularJS: Scope variable not updating in view. You should this. I would assume these should automatically update since the icons are getting updated in Component1's constructor from Service1. Jul 17, 2023 · Problem: Variables are changed successfully, I know that thanks to console. Console logging shows they are updated in the component. How can I get these variables to update when Component2 calls the signIn() method? Jun 27, 2018 · I suggest you using the angular service or @Output and emit events in the root and listen them in the header. service) through component (queueSearch. You could however assign the subscription to a variable and call . Oct 20, 2018 · It looks like the playing is not being capture as a part of change detector mechanism in Angular. component. Apr 15, 2017 · Angular 2, variable is not updating inside service 1 angular - I have an element in the view bound to a variable in a service, but the view is not getting updated when the service is updated Dec 29, 2017 · I'm trying to use a service variable in component but when service function is call that updated variable not change in component here is my service import { Injectable } from '@angular/core'; im Apr 24, 2015 · @huanfeng In your plnkr you did not overwrite the list in a child scope. As mentioned in my comment, Angular HTTP observables complete after a single emission. I can access it in any page, but when I update that variable, the changes will not affect while accessing it in another page. I have a hunch that I need to make the variable an observable, but I am not sure if that is overkill and if there is a simpler solution. Provide details and share your research! But avoid …. waypoints]; waypoints. Viewed 2k times 1 I have a list of images. Hence you have to tell when Angular should update the view. component click() will work and pass some string to service. However, when I try to access that variable from another component, it returns it's original value. Whoever, the view doesn't update. jwt. I don't know why the button makes the variables update. varExample = . What you could do is : You can manually perform change detection; Reassign entire array mySaleModelArray2 using temp array (not a good solution though). In this case the component that subscribes to this service would probably still execute the callback passed to subscribe() on name change, even when it is already destroyed because the subscription stays active until the component gets garbage collected, which probably won't happen until the Jan 29, 2019 · You might use Subject or if you need an initial value then BehaviorSubject from rxjs in your service then subscribe to it in you component. I have problem with that : updateSoruLst( soruLst : [SoruModel] ) { this. Ask Question Asked 9 years, 4 months ago. So a take(1) would be redundant. log. There are a few ways to share the data you need: I would suggest looking at the Angular Data Binding page, in particular the section on Property Apr 24, 2022 · After the second submit of this. and pass to all child by @Input() Now my problem is a parent. and service will change variable clicked . Nov 24, 2017 · The problem is that you are providing the service at component level, that means, that all your components, that have the service added to providers array in component will have their own instance of service, so this is not a shared service at all. Mar 29, 2014 · AngularJS - variables not updating in view (not using scope) Hot Network Questions Why does one have to avoid hard braking, full-throttle starts and rapid acceleration with a new scooter? Apr 1, 2013 · I've just been starting on AngularJS and I'm still trying to understand creating services. Jan 15, 2021 · Hello, I’m doing the Angular’s Tour of Heroes, but I have a problem with the last topic. projects. When using angular as an application developer you have to spent so much time to understand how angular does this or does that and how to workaround things like questioned above. Service: isUpdatingSubject: BehaviorSubject<boolean> = new BehaviorSubject(false); // inital value is "false" isUpdating = this. How do I solve this issue, can I use the |async pipe. So, you just need to update that array. markForCheck(); See this answer explains it deeper. You should use this as a last resort only! Mar 15, 2021 · The answer is already in the question. Aug 3, 2020 · I have a variable in my Component that it is updating while using console. It demonstrates the use of BehaviorSubject and how one component updates and the other listens and reacts in real time (full working example here). Fix : You have a couple of choices. When the app first opens or is refreshed, element_id is undefined (not sure how to fix this), but as soon as I click on any button, element_id in the nav component and Jun 8, 2018 · Service variable not updating in parent component while changing it in child component Hot Network Questions Once decohered, is the quantum system always fully transitioned from superposition of states to one definite, 'classical' state? Jul 5, 2020 · I could not make it persistent behavior in HTML part while using subscribe to the http client in the Anglar 9. 1. It is only showing the first uploaded image. I want to change the variable name value to "rahul" and Oct 30, 2017 · I am using Angular 2. I am updating all the 3 variables from a child component using the service's getter-setter methods. What I would like is that when one component changes a value in that same service, that new value then gets sent to every component that calls that service and subsequently updates that value in a component variable. Asking for help, clarification, or responding to other answers. Make sure, you have added the service in app. . I know that the problem is related to trigger on service, since I puted a button to click when doing the method, and then variables are updated. I also then tried creating an observable to use in the template instead of the BehaviorSubject itself and i directly called the service variable instead of the component variable in the template. Maybe a local copy is made of the data at the controller level, maybe the service is declared in multiple modules which results in multiple instances of the service instead of a singleton, maybe the data is not updated but an observable is or visa-versa, maybe the Mar 9, 2022 · When getting results from the service I can see the console. Because you did not completely re-assign to it. setSomeVar(‘bar’)` you are resetting `service. tmwf oipk ghiu bgu qbnlv ovedhx kkbb bpdwnb wauiwg xvwisi