Angular constructor wait for observable. Testing service method returning observable with delay.
Angular constructor wait for observable. Modified the DEMO to show you how to do that.
Angular constructor wait for observable apiRoot + '/me'); } Jan 23, 2017 · I have an AuthGuard (used for routing) that implements CanActivate. getData() . Something like this: Jul 13, 2022 · Need some global service added in app. Jan 26, 2018 · I have a service used as a local data store to share data across the app. ts for store user info after login; in service add: loginned$ = new BehaviorSubject<boolean>(false); after calligc func login() on success add this. RxJS’ Observable with plain Promise so that I can use async and await and get a more intuitive code style. myObservable(). but when i call temp PO number create service it does not wait for response. storageSubject. asObservable(); announceMission(mission: string) { this Aug 22, 2018 · I tried it in Angular 6 and I was able to do it like: // dummy Observables let a = of([1]). This service makes a few rest calls in the beginning to initialize some data. Nov 27, 2017 · Below is my code, in the for loop I call the delete method, but I want to wait for funcion to finish, before call it again. routing. Ebook 1: Angular standalone components; Ebook 2: Learn Angular In 15 Easy Steps; Ebook 3: Practical Angular: Build 5 Apps From Scratch! Ebook 4: Build a Movies App with Angular 18 and Tailwind Feb 16, 2018 · I have a variable called loading ( and it's false in the beginning and it is a boolean variable ) and a button which its text depend on that variable. May 11, 2019 · I’m currently evaluating the pros ‘n’ cons of replacing Angular’s resp. newIds) is runned first and is always empty because the subscribe doesn't wait for response to come from the backend. I can't seem to get this to work and I think I'm just making some mistakes on how I'm implementing the Observable. If we subscribe to a successful result in the constructor, it will simply continue executing the rest of the code and initialize the user interface. r/Angular2 exists to help spread news, discuss current developments and help solve problems. toPromise(); }); } But i can tell you for sure that you can do a The Complete Book On Angular Testing. 1. Feel free to use it or not. skipUntil : ignore emitted items until another observable has emitted. In the below code, canActivate needs to return an observable boolean. The main problem is that to reload it I have to make a http call to get the new token and then I will re Router 4 should really support hot routes, that is views that are updated once the observable emits new data. Luckily this isn't needed because this. id = id; this. This is my Jsonreadservice. So, let’s bring them in! ngFor and Async Pipe. ionic/angular wait until service is ready. The methods like 'get' of the HTTPClientModule, return observable, which we can subscribe in the components, and notify view to update the DOM. A false boolean means either not allowed to access or refService call failed. ts: Mar 26, 2019 · You can't, a dispatch is a fire and forget that you can't wait on. What I did was to add the isLoginResolved to the state. json()) I want to replace it with ngrx effects and st May 25, 2020 · The call and subscription are asynchronous by design. This can be done by utilizing RxJS pipeable operators ('rxjs/operators') such as tap (for side effects like setting newAccessToken) and switchMap or mergeMap in combination with pipe(), returning an observable of type Observable<HttpEvent<any>> to satisfy the HttpInterceptor interface: Jul 19, 2020 · With Book class defined as: class Book { id: number; name: string; constructor(id: number, name: string) { this. Something like this should work: import 'rxjs/add/operator/share'; import 'rxjs/add/operator/map' import 'rxjs/add/operator/mergeMap' // Mar 27, 2018 · Generally I agree with this answer, however due to the use case I would recommend ngShow over ngIf. Oct 11, 2020 · I would say better to use an async pipe and let angular handle the unsubscribing. Then at some later time the data can be retrieved with a getter. subscribe(isLoggedIn => this. Aug 2, 2017 · Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. article in that The AsyncPipe subscribes to an observable or promise and returns the latest value it has emitted. authenticated$. Here how it works right now, I convert my promise to Observable: export class SomeS Sep 27, 2018 · In a component, I subscribe to two services. The problem is that both functions are being called at the same time so since the request of function 2 is the response of function 1, there's no response yet so the second one Feb 28, 2022 · The AsyncPipe subscribes to an observable or promise and returns the latest value it has emitted. React, Vue etc). Wait untill observable complete. I have an Angular2 directive, MyDirective and a service MyService The service makes an http call in its constructor to fetch Jul 11, 2017 · The solution I came up with is to use a shared observable, save the request as a hot observable that way when the report button is clicked it will wait for the request or immediately generate if the request is complete. Nov 10, 2017 · I'm using a Guard on an Angular application to resolve initial critical data. Yes the function inside subscribe will "wait" but other code inside ngOnInit but outside subscribe will not wait. 1- Your method is returning an array and you subscribed to it (although has async issue) 2- Method is returning array at the end and it happens before your promise result become ready The second and third test reveal an important limitation. Check code below. isLoggedIn$. EDIT: Regarding the fact that you're using Observable, you can use . module. The following example binds the time observable to the component's view. currentData. ts. This is something you must keep in mind when implementing asynchronous calls, regardless of whether they're in the constructor or not. import {Injectable} from 'angular2/core' import {Subject} from 'rxjs/Subject'; @Injectable() export class MissionService { private _missionAnnouncedSource = new Subject<string>(); missionAnnounced$ = this. This is my first project and I noticed my function doSomething() returns a value before it was properly calculated. In the past I have found it ok (when I had async await), So as an alternative, as I get a couple for values from the store via the selects, and then a promise from a service call, I just have all the observables (using the from for the service call) , and perhaps use combineLatest on them all? Jan 10, 2016 · Otherwise I have a promise to an observable, and I have to unwrap twice in each caller. main$. I'm working with Angular, I need to call a function (defined in a component) from a service. isLoggedIn = isLoggedIn) } Nov 26, 2021 · Use the Observable constructor to create an observable stream of any type. “from”:- Converts an array, promise, or iterable to an observable. Where this becomes a potential challenge is on the implementation of the constructor, because "super" is now a promise. I looked up async functions but I do not understand ho Jun 16, 2017 · "Use complex stream with nested actions", I don't find it is a "really complex" stream, it perfects fit my need where others don't really pleased me: 1: I can not maintain all that duplicated with no real "good" reasons. . name = name; } } I go ahead and create Jun 7, 2020 · But Angular is reactive, this means it’s all about Observables. I'm working on this project that uses ngrx and Angular 2 and RxJS Observables to replace this one that uses JQuery. A resolver returns an Observable. to Aug 23, 2024 · “of”: - Creates an observable from a set of values. Asking for help, clarification, or responding to other answers. After a successful or failed login/auto-login I set the property to true, because the login/auto-login happened. More importantly (which I know I did not mention), the purpose of the stateful information is to chain other observable information. service. What you need to do first is to convert your focus event to an observable using Observable. Nov 9, 2020 · First check if the user info is present. Basically, I'm trying to automatically renew an user login, given a valid token. An observable begins publishing values only when someone subscribes to it. routeSub = this. As ngIf will not post the tag to the DOM, which could cause un-desirable ssues with layout. That's how pages have worked I'm new to Angular so bear with me. zip operator: About zip operator. subscription. sub Oct 3, 2019 · I have an angular entity Z which one of its properties is a list of another entity Y, I need to delete entity Z and when I do it I need to delete the list of entity Y inside of it. canActivate(route: ActivatedRouteSnap Jul 6, 2018 · As @jfriend00 mentions in your comment discussions that this is a dupe of similar questions, whenever using asynchronous functions (Promise, Observable) you should bubble up the asynchronicity back to the call and . For this, we’ll introduce Observable of() from RxJS and demonstrate subscribing to an Observable stream via the async pipe and update our Aug 24, 2020 · I cannot say that this is wrong: ngOnInit(): void { // 🔹 mark the upper function with async this. However, I need it to wait (I know "wait" is a dirty word in front end) for the bearer token to come back from the server before it can return. I can't find a simple tutorial for Observable and its syntax. Max wrote a great article about this, which you may find here. CanActivate { constructor( public auth: AuthService In productService. Feb 28, 2017 · Maybe I'm missing something. The problem, that guard doesn't wait completio I am very new in Angular. Component. The operator take(1) makes the observable "cold" -- meaning it is completed after the first value is emitted. or look through asyn pipe sources and try to implement something simillar – Andrei Commented Sep 24, 2023 at 8:30 Oct 1, 2017 · I was trying to return result from FileReader and I found this implementation. Mar 5, 2020 · What can I do to make resolver wait until it gets images from the API. Oct 2, 2020 · Angular is Google's open source framework for crafting high-quality front-end web applications. In the AuthGuard you check the result of authenticated() method that will most probably return false as the user property is still not set. So you start be making a request to the currentConfig() and then switch to the next interceptor when the config is emitted. timer = timer(3000, 3000); this. I am receiving an order from a customer with PO number but some time customer order missing PO number so i just create temp PO number and fill it in form and receive order. authService. pipe(delay(1000)); let b = of([1, 2, 3]). Or wait for loading to finish if that's still in progress. Construction time is when 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 Sep 29, 2017 · Make the baseUrl into an Observable that you share() (so many calls can use the same result - it's making the observable hot) and use in your other calls. complete() May 13, 2017 · I need to check te back-end for authentication status, however te code completes before te observable return is finished. Feb 26, 2019 · There are two issues in your code. Subscribinglink. It checks for a logged in status, then gets an id from it if it exists and checks for a profile assigned to that id. @HereticMonkey yes it does, because it's framework specific, it's observables. Instead, when using Angular 2 RC, replace references to router with router-deprecated to continue using the beta router. ts, subscribe to the Observable<Article> returned from productService and set value for this. The Angular framework and tooling do not enforce this convention. subscribe() where currentData is from a BehaviorSubject private currentDataSource = new BehaviorSub Sep 18, 2019 · Angular has a very nice module HTTPClientModule. And the child component needs to know the length of the data in order to do something. This pattern of Angular development doesn’t follow an Observable data source pattern. In the check it calls a service to to get a value Sep 1, 2017 · I am trying to create a mock service as follows. But since it is outdated, I'm wondering how to implement the same using ES6 Promises or Rx Observables. The Angular testing environment does not run change detection synchronously when updates happen inside the test case that changed the component's title. subscribe((response => { payeeName = response })) Mar 30, 2022 · I had the same behaviour and managed to fix it. g. 100+ pages with more then 30 testing examples and secrets you need to know about testing Angular apps. It will always give the last value immediately after subscribtion, which can be more useful if you want the Mar 8, 2018 · I'm expecting Angular to wait until my loadConfig() function resolves before constructing other services, but it is not. the first one, this. app. You probably want to use the RxJS filter and take(1) operators. e. Testing service method returning observable with delay. The constructor does not block and wait for the call to finish before exiting the constructor. Share Improve this answer Dec 13, 2018 · You can use ng-busy (or basically any other npm component out there) for displaying a loading indicator in each http call (promise or observable in your case) in your app. However auth guard does not seem to wait for the request to finish and gets a boolean false as the predefined value of (isLoggedIn$ observable) auth guard. Jul 4, 2017 · async pipe need an Observable or a Promise from what I understood, that's why the only way to make it work was by creating a Promise; I didn't use the resolver approach because it's used when you arrive to the component through Angular's routing. timer. toPromise in order to work with ng-Busy. getFileTree(params. It look like this: Injectable() export class Nov 10, 2017 · The requirement is coming from the management b/c this is the way they always done switching between environments for the . 2. Oct 27, 2020 · you're mistaken that you'd put your code "after" the subscribe handler, you'd need to put it INSIDE of the subscribe handler, but regardless, you need to use a subject of some kind here, probably a ReplaySubject in this particular case Jun 1, 2019 · // Do not forget to unsubscribe. my service is like import { Injectable } from '@angular/core'; import { URLSearchParams } from '@angular/http'; import { Observable } from Jun 20, 2018 · Please use service as a singleton. getAll() Observable method is working, but it is being late. May 18, 2016 · The problem is that we convert observable into different type with . pipe(delay(2000)); let c = of([1 Dec 28, 2016 · Basically , create an observable , subscribe to it with delay and the with flatMap map it to a new observable and return that for subscribers. subscribe If you the ReadTableAsync() method returns an Observable, you first need to use the toPromise() method to return a promise from the observable before you can asynchronously await for it Share Improve this answer Jan 3, 2017 · I don't know how to make (3) wait until (2) has finished. html#34, a page will scroll to that point. wait until it completes then emit) Note that anything emitted from the observable passed to skipUntil will cancel the skipping, which is why we need to add last() - to wait for the stream to complete. flare = await this. timerObservable = this. _myFiscalDocumentsService. The Angular2-future way to implement this will be via the @Resolve decorator. subscribe(async (params) => { this. It turns out my question needed two important solutions to make it work as a proper stream of observable actions, which is what an effect requires as a return. take(1); } Edit: canActivate waits for the source observable to complete, and (most likely, I don't know what happens behind the scenes), the authenticated$ observable emits . Sep 7, 2016 · Seems like it's still being instantiated before parent component has the data. pipe( combineLatestWi Mar 2, 2016 · A constructor is a function that returns an object. Basically the console. getPerfisList to finish, iterate the response as this. Dec 3, 2019 · I need to wait for perfilService. skipUntil(sequence2 Apr 22, 2021 · In my app. http. subscribe it there. What you should do is use the async pipe in your component markup, and conditionally render buttons etc. This is built on the top of RxJS Observable package. intercept has to return next. Sep 15, 2021 · You probably want to use an Angular resolver here instead of a guard. Jul 11, 2017 · Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. But when cultures array is called, Configuration service returns empty cultures array. Since you are expecting exactly ONE event to happen you should use single() which will throw an exception if there is more than 1,while not throwing an exception when there is none. next(message); } StackBlitz example. Welcome! Members Online Oct 10, 2022 · There is a big difference between the constructor and the ngOnInit. Jan 5, 2016 · What is the correct way of unit testing a service returning an Observable result in Angular 2? Let's say we have a getCars method in a CarService service class Angular 12 added support for Observables, so this should no longer be an issue if you're using Angular 12 or newer. I have the following call in my data service: completedTasks(): Observable<Array<Todo>> { return this. For us, the most important thing is, the constructor is called when Angular constructs the components tree, while ngOnInit is run after the change detection when all bindings are updated. May 10, 2018 · Here's my Angular auth guard. If you pass an anchor id in a url like mypage. im Feb 11, 2019 · I have a timer in my main component of 3 seconds. x the behavior is different. you'll want to use a local subject to accomplish the goal as wanting to kick off each observable as it is selected and waiting for them all to be done complicates things a little (but not too much): Nov 6, 2020 · My router is like this const routes: Routes = [{ path: '', canActivate: [AuthGuard], resolve: { user: UserResolver, }, children: [{ path: 'home', canActivate Ask questions, find answers and collaborate at work with Stack Overflow for Teams. Use forkJoin to Wait for Multiple Observables to Complete. canActivate() { return this. resolver. Right now, Angular waits until data is received, shows page and then tries to get images of the post. I came up with following example (code is in Typescript): Dec 27, 2018 · I am facing issue with Observable. This component is part of a larger component and it's not instanced through routing like any other Oct 28, 2020 · What you should do instead is return the inner observable from the function, and subscribe where you actually need it. Dec 4, 2019 · I am trying my first Angular 8 Crud Web app and wrote a page to list some company names from WebApi My Service is correctly getting data and Iam able to print it on console //Service. Although I used a recommended workaraound from here it still is delayed and does not wait in execution. In short words: Make a new observable out of data from the original observable. The observable continuously updates the view with the current time. It produces cleaner code; lets consider the code where the subscribing is in the constructor Apr 23, 2020 · canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree } It can return a simple boolean or a Promise, or an Observable. Sep 5, 2019 · Subscribe to our Angular Newsletter and Get 4 Angular eBooks for Free. If async constructors were functions that returned promises of an object; this seems conceptually consistent. unsubscribe(); Oct 14, 2018 · I am having trouble emitting data from my observable using *ngFor. So yes and no. someService. Jan 4, 2020 · I have a service which loads some data in it's constructor with an Observable. subscribe - while we should not (it does not return observable). Also, rather than subscribing and setting values, you can just maintain an observable that has the values mapped in the object format you want to bind to the template. When a new value is emitted, the pipe marks the component to be checked for changes. handle(request). I can't for the life of me find a pattern that accomplishes this. @Injectable() export cl Sep 20, 2017 · right now I have a resolver calling standard service and returning an Observable: return this. myFirstService. map(data=> data. This means that if it changes, the observable will be emitted a new value and this will cause your component to re-render. Transformation Operators: — Change the data emitted by an You need to pull this out of your constructor, put it in a service that provides the stream, inject that service into your module/component through the ctor, then subscribe to that observable and mutate or pass that state as you need. One of our typical Sep 5, 2019 · Indeed, A and B are just interested on the calls they make, they don't need to know other stuff undergoing over the data service, this one should handle the requests along they come waiting for one to finish before triggering the next one Jan 23, 2019 · I want to delay this pipe to return value only after 2 seconds. The activated route should flow the data and if route change is needed it should happen after the observable has emitted the first value. See full list on dev. Provide details and share your research! But avoid …. ts routing = [{ path: '', component: AppCompo Oct 5, 2020 · The code you provided seems fine. Writing the problem statement. Oct 10, 2018 · I am new to Angular and I am stuck. In the service, have an observable as a variable. Mar 12, 2019 · 1. Router is not released for Angular 2 RC as of this edit. next(), not . _missionAnnouncedSource. Modified the DEMO to show you how to do that. 2: 👌. That "1-2-3" observable won't emit any numbers until you subscribe by calling the observable's subscribe() method. This is a feature, not a bug – Jun 18, 2016 · The problem is with your code. Feb 25, 2019 · I'm trying to implement a guard in my project, that should wait until ngrx-store's loading complete and after this check is user authenticated or not. loginService. It's built with Angular but the RxJS code isn't Angular specific and could be used with any front end framework (e. I read this Jun 28, 2016 · I don't know if I should post any code for this. log(value)); setTimeout(() => {// Do something with the subscription. Here are some examples of waiting for subscribe to finish in Angular: * **Waiting for a subscribe to finish before calling a function:** const subscription = observable. May 16, 2018 · HttpIntercept. When I reload a page, for Apr 5, 2022 · I've seen a few answers on SO regarding this same topic, but I believe in Angular 13. Jul 13, 2019 · in the use case described in your update, you'll still want to use a higher order observable, but forkjoin is not what you want. I'm trying to resolve the guard waiting for this two When I reload my page, it always goes to a blank page instead of the same page. Add observable to your component which emits after all the animations finish (you can listen to . Here it is in action: Jul 25, 2022 · the function inside the subscribe runs everytime the observable event fires but take(1) ensures only one event fires. When I duplicated angular/rxjs, async questions with that answer, people got confused and said thening the observable doesn't work; this is obvious for angular answerers but not to you apparently. params. Sep 2, 2016 · all you need to do is force the observable to update: canActivate(): Observable<boolean> { return this. store. Question: how to wait observable method until it completes? Dec 30, 2016 · I'm passing async data from a parent component to a child component. detectChanges() trick as you won't have a component to detect changes for. validaUsuariosPerfil. Read more about switchMap here. A subscriber function receives an Observer object, and can publish values to the observer's next() method. then or . It should return the data right away if it's present. ts export cl Feb 9, 2018 · I've been building a SPA with Angular 4 on the front end and ASP. We can rewrite your getUser function like below (note that there is no need for the imperative setUser-function) public getUser(): Observable<User> { return this. But I will if required. getMessage(). storage$: Observable<any>; newMessage(message: any) { this. Apr 24, 2022 · Other than using a truly old-fashioned call to XMLHttpRequest(), your best strategy is to wrap the Observable into a deadend angular method like a custom function, ngOnInit(), the component's constructor, or a routing guard and add on a callback method at the end of its data processing pipeline that jumps to your synchronous code. acronym = params. Try this For ex : I've an array payeeName = [ ] SomeFunc(){ // subscribing to an observable which makes http get call getPayee. user. ts Nov 12, 2015 · This is an example from Angular2 docs of how you can create and use your own Observables : . select('teams') is an observable. inside the timer I perform http call- constructor(){ this. After which the translations are probably already set, and they cannot be changed for some reason. For example, in the following code invoking in the constructor getProductById() that returns an Observable would be wrong as the property productId would be undefined: Jun 10, 2021 · Angular observable return undefined results. The problem is t Jan 29, 2024 · In the parent component, I've defined an Observable variable named results$, and in the view, it is utilized as follows: controller: this. subscribe(value => console. May 25, 2019 · The intercept function just needs to return an observable. The reason behind this is canActivate method which is checking for the user's permission gets invoked as soon as the user refreshes the page and it is not able to get user data immediately. get<User>(environment. Also i thought it was enough to give the credit in the answer but i Mar 10, 2022 · I'm trying to subscribe to an Observable and assign some data from the response, but somehow my code it's not waiting for the response. 3: I don't want to add this correlation logic which will require to manage their lifecycles. Could this be because the parent component is what's waiting for the resolver, not the child component? But the child component doesn't have a route associated with it, and the parent component is the one fetching the data, so I'm not sure how else to make it wait. usuarioperfilService. I have 3 files: WarningComponent (shows a warning modal (bootstrap)), modalService (this will open the modals) and votingComponent. However, when discussing how we should initialize them, colleagues and I came Sep 24, 2023 · return the observable from your pipe and then call the | async pipe to "unwrap" the observable. Jan 20, 2019 · I want to call a async function readUsers() within the constructor or ngOnInit(). There are lots of useful tutorials, just search for "Angular Resolver". A resolver ensures data is available and loaded before a route loads. @apricity @AgentME Actually you should NOT use either take(1) nor first()in cases like this. The constructor takes as its argument the subscriber function to run when the observable’s subscribe() method executes. name). Apr 16, 2019 · You would not subscribe() inside the interceptor, instead you would return an Observable<HttpEvent<any>>. export class StoragePipe implements PipeTransform { constructor(p Jan 8, 2023 · 2. That Dec 6, 2017 · However, to retrieve the translations using ‘ngx-translate’, we get an ‘Observable’ returned. You can't use "hot" observables (that emit multiple values) with guards, because the guard's subscription will keep waiting for the observable to complete. next(true); Angular: wait for Observable inside a function before returning result Hot Network Questions The British used to (still?) classify their guns by weight in pounds rather than caliber. name; // 🔹 now we can use await but we need to convert the observable to promise this. So I have implemented the Apr 27, 2017 · I have a directive that is creating in code an instance of component template he uses and set its innerHTml, which will change the tempalte dimension: var factory = this. Jul 31, 2023 · Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. My Angular application does a lot of Http Requests, so I'd like to display a spinner in order to notify the user that the application is working (and it's not "freeze"). The Service. getAllProductsFromACategory() replace subscribe with map so that the method returns Observable<Article> In constructor of product-list. Jan 26, 2018 · In DashboardComponent, cultures array is called from Configuration service. I have a company and a Project class, in the Project class there is a com Angular is Google's open source framework for crafting high-quality front-end web applications. 0. ngOnInit() { this. public makeRequest = (): Observable<any> => { return this. ts export function initializeConfig(config: AppConfig){ retu Mar 2, 2021 · Context: I have created a route guard on my Angular application. result$ = this. Oct 11, 2019 · Wrap your data myarray into Observable, the you will be able to use all Reactive Programming RxJS using pipe function, Operators Like map,filter,swichMap,etc Jul 9, 2021 · Hmm, ok. Lastly, since observables appear to be the norm in angular 2, I don't think I want to start wrapping observables in promises. If not then get the user info from ref service and return a new observable of type boolean. Which would result in an undifined. subscribe // because it consumes observable and returns ISusbcriber ); } Sep 19, 2020 · The example shows five observable values that get emitted in sequence, each waiting two seconds for a Promise to resolve. The test must call await fixture. firstObservable$. This is an extension to the scenario of testing service method returning observable with a delay. Apr 12, 2018 · ngOnInit() is used to make sure that the component's properties you use are already initialized. log(this. ngShow will apply and reserve the expected "real estate" on the DOM for the hidden tag, but will only populate once the data is ready. For maintainability and readability, it's usually best to follow the trailing $ to name observables. Please read the official documentation Jan 12, 2016 · EDIT: This answer works for Angular 2 BETA only. Oct 29, 2024 · Angularのエコシステムとの親和性: Angularはリアクティブプログラミングの思想に基づいて設計されており、Observableの使用が推奨されています。これにより、Angularの他の機能（例えばフォームやルーティング）との統合がスムーズに行えます。 The Angular framework and tooling do not enforce this convention. done event for all animations), and use it in the CanActivate guard. In the constructor of Configuration service cultureService. async constructor functions in TypeScript? How can I delay/wait with execution of my readUsers() function? Mar 2, 2023 · combineLatest works on the principle: When any observable emits a value, emit the last emitted value from each. When a guard is active on that route it activates the guard where it runs a check. Sep 23, 2019 · I resolved in this way, an if-else condition wasn't necessary. Sep 20, 2021 · I am implementing Angular strict mode in a project where observables are heavily used in the controllers and templates. Jun 28, 2019 · I have Angular Service which make some http requests, but I need to get headers for those requests from Promise. How the problem is that the child compon Nov 15, 2017 · You don't have to wait for it to resolve to be able to render your component that depends on what the resolved value is. For your use-case (pre-load some configuration data) it would be expected that the Observable used in APP_INITIALIZER would essentially do one thing then be done - in fact, this is exactly how it would work if you were to use a Promise . Here's the particular problem I'm trying to solve. Note: If you want the observable to have an initial value, you can use BehaviorSubject<any>. What would be the idyllic way to delay such observable pipe. If you want to wait for both of your observables to emit the values, you should use zip instead of combineLatest, I've modified your below create-session. GRAB YOUR FREE COPY Dec 1, 2022 · The APP_INITIALIZER expects either a Promise or an Observable, which satisfies the interface - a Subscriber does not, so yes this is a compliant solution. perfilData and then start to call this. On the version 4 of Angular I was duing it like this: // app. subscribe( // this is wrong, we cannot return . I wrote a method to do that for me like this: Aug 22, 2017 · I would use the Observable. Wait in the function that returns observable. fileTreeService. Jul 27, 2017 · Angular : Wait for an Observable to finish before returning the value. I highly recommend you Google angular antipatterns about shared state in rxjs observables. Oct 21, 2021 · Hi I am trying to check when a token is about to expire and reload it with the access token. Also, I don't think you need to convert the Observable to a Promise inside your LoginService. Net apps. fromEvent, then use the zip operator along with filter like this: Jan 14, 2019 · If you are trying to test a non-component Angular item (ie AuthGuard with Service dependencies), you won't be able to use the fixture. component. ts, I have the code in constructor to fetch the json file and then parse it's data to a variable which is further passed to the message module. isLoggedIn(); } My problem is, that the CanActivate-result depends on a http-get-result - the LoginService returns an Observable. last: emit last value from a sequence (i. Feb 13, 2020 · Learn how to display a loading spinner while waiting for data from an observable. This can be done by configuring service in provider list in the root module. route. whenStable to wait for another of change detection. NET Core 2 on the Backend. It actually causes a lot of trouble b/c of human factor but this is not the battle I want to fight now b/c being relatively new guy on the team. If you want all the animations in your component to finish before proceeding with the navigation, you should implement CanDeactivate guard. loginned$. subscription = this. constructor (private authService: AuthService, private router: Router) { this. Wait for providers constructor to be ready before using it. Try Teams for free Explore Teams Examples of waiting for subscribe to finish in Angular. Jul 12, 2018 · I need to wait until the getPermissions() observable is complete before calling the checkPermissions() method. The reason load_one works and load_two doesn't is that Angular 11 and older waits only for Promise s; not Observable s. 4 and 5: I love NgRx too much for that. scofhw syhvaf syivi set ghbt hvzvz dfrsvzcc ccmu wptvdyl nrvm