observable

问题 I am trying to implement a navbar that shows different links based on whether or not a user is logged-in. I am using the angular2-jwt library which provides the tokenNotExpired() function. I have 2 routes, /home and /login . I have a navbar component which is outside of the <router-outlet> , which means it is initialized only once and not every time the route changes. After successful login, I am invoking router.navigate(['/home]) . The home and login both have checks for if a user is logged

问题 I'm having difficulty with a component that doesn't refresh upon log in. The component is navbar.component that contains links to my pages/components. On it, there is a "login" link that renders login.component on which I can provide username and password and click the login button. login.component uses user.service which calls the backend with the username and password provided by login.component, stores the received token and redirects to '/'. At this point, the "login" link on navbar

问题 I have a block of code where I'm calling observables in a chain like so: getData().flatMap(results => { return callNextDataMethod(results); } .flatMap(results2 => { // next operation and so forth }) Now, I understand that flatMap will allow me to pass the results of the previous observable to the next one. However what I need is to both do that as well as pass the results on the first. Let's assume that I do some cleanup, validation, etc on the data that comes back in getData and I want that

问题 I have a viewModel with an observableArray of objects with observable variables. My template shows the data with an edit button that hides the display elements and shows input elements with the values bound. You can start editing the data and then you have the option to cancel. I would like this cancel to revert to the unchanged version of the object. I have tried clone the object by doing something like this: viewModel.tempContact = jQuery.extend({}, contact); or viewModel.tempContact =

问题 I build a simple confirmation dialog service (Angular 2) with this method: confirm(body?: string, title?: string): Subject<void> { this.confirmation = new Subject<void>(); // ... show dialog here... "are you sure?" return this.confirmation; } _onYesClicked() { // ... closing the dialog this.confirmation.next(); this.confirmation.complete(); } _onNoClicked() { // ... closing the dialog this.confirmation.complete(); } Usage: confirmationService.confirm().subscribe(() => alert("CONFIRMED")); If

问题 I have a few observables. And I need to know which one triggered the subscribe. Observable.combineLatest( this.tournamentsService.getUpcoming(), this.favoriteService.getFavoriteTournaments(), this.teamsService.getTeamRanking(), (tournament, favorite, team) => { //what triggered combinelatest to run? }).subscribe() 回答1: Short answer is: You don't know. You could implement some workaround, however this is really ugly and I would recommend rethinking the usecase why you need this and maybe if

问题 I've started learning Knockout and I'm having some trouble filtering an observable array on a button click and displaying the results. This is my model: function Product(data) { this.id = data.id; this.name = data.name; this.price = data.price; this.description = data.desc; this.image = data.image; this.genre = data.genre; this.show = data.show; this.offer_desc = data.offer_desc; this.offer_id = data.offer_id; } function ProductModel() { var self = this; self.products = ko.observableArray([])

问题 I'm rookie in Angular 4 and I need some help. My code in console display error but in my template everything display correct. Could someone help me understand what happend? Error ERROR TypeError: Cannot read property 'Tytul' of undefined NewsDetailsComponent.html:7 ERROR CONTEXT DebugContext_ {view: Object, nodeIndex: 12, nodeDef: Object, elDef: Object, elView: Object} news.ts export interface News { Ident: number; Tytul: string; Tresc: string; Data: string; } news.service.ts import {

问题 I'm trying to wrap some listener-pattern based API to an Observable. My code roughly looks like following. def myObservable = Observable.create({ aSubscriber -> val listener = {event -> aSubscriber.onNext(event); } existingEventSource.addListener(listener) }) However, I want my observable to immediately remove the listener from the underlying existingEventSource when the observer calls subscription.unscribe(). How could I achieve this goal? 回答1: The Subscriber abstract class actually has a

问题 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: ... export class CarService{ ... getCars():Observable<any>{ return this.http.get("http://someurl/cars").map( res => res.json() ); } ... } If I try to write the tests in the following way I get the warning: 'SPEC HAS NO EXPECTATIONS': it('retrieves all the cars', inject( [CarService], ( carService ) => { carService.getCars().subscribe(