I'm diving into the world of RxJS and trying to grasp its concepts. During some testing, I encountered a puzzling issue that has me stumped.
Below is the snippet in question :
let item = { id: 1, name: 'chair' };
const asyncItem = timer(2000).pipe(() => of(item));
asyncItem.subscribe(data=>console.log(data))
I anticipated seeing item displayed in the console after a 2-second delay, but strangely it appears instantly. Where am I going wrong? Grateful for any insights. Thanks.
If you want to trigger an emission after a certain number of seconds, make sure to utilize the delay operators instead of using timer.
To achieve this, modify your code as follows:
const asyncProduct = of(product).delay(2000)
asyncProduct.subscribe(data => console.log(data))
UPDATE:
You can also opt for the timer operator within a pipe, combined with another operator like shown below:
timer(2000).pipe(
switchMap(() => of(product))
).subscribe(data => console.log(data))
By following this approach, the value will be emitted after 2 seconds, helping you accomplish your desired outcome. This presents an alternative method compared to the initial example provided earlier.
I have been working with Angular 9+ along with karma test runner and jasmine test framework for my unit tests. My focus is on unit testing only the app component which includes dependency injection: app.component.ts import { Component, EmbeddedViewRef } ...
Currently, I am developing a component using Angular 5 and Ionic 4. My objective is to include a Refresher event to hide the refresh spinner whenever the user triggers the final function to conceal the spinner. Provided below is an excerpt of my code: e ...
While learning about TypeScript, I encountered some confusion regarding how it handles const variables. Let's consider a scenario where I define an interface for a number: interface MyNumber { value: number; } If I then create a constant MyNumbe ...
The following code snippet showcases Service 1, specifically the uploadAttachment method which executes an http post call. This method is invoked from Service 2. However, in Service 2, the instance of Service 1 is consistently undefined, resulting in a fai ...
Implementing basic collapse in Angular using ElementRef has proven to be a challenge for me, especially when dealing with HTML content within an ngFor loop. I need to pass the index value to the click event so it can retrieve the ID of the element. Check ...
Is it possible to notify users that both passwords should match and they need to enter at least 8 characters after typing? There is currently an issue where a notification appears for entering less than 8 characters, but the password reset still proceeds ...
Can anyone assist me in understanding why this code is not functioning correctly? Here's what my index.ts file in Hapi.js looks like: import { Server, Request, ResponseToolkit } from '@hapi/hapi'; import * as Loki from 'lokijs'; ...
Upon encountering this code snippet: import { useState } from "preact/hooks"; export default function Test() { const [state, setState] = useState(null); setState('string'); } An error is thrown: Argument of type 'string' ...
Suppose I receive a string containing special characters that needs to be transformed using filter/pipe, with the additional requirement of capitalizing the first letter of each word. For instance, transforming "@!₪ test stri&!ng₪" into "Test Stri ...
Is there a way to preview a file in the browser before downloading it in NodeJS? This would allow users to make sure they are choosing the correct file to download. Currently, I have this code for downloading a file: app.get("/download/file", (req, res) = ...
Is there a simple method to centralize and share one node_modules folder among all Angular projects, thereby preventing the need to download the same dependencies each time we start a new project? If so, is this approach recommended (what are the pros and ...
I am currently working on building an Angular 4 app with server-side rendering and language-specific route paths. I am using Angular CLI version 1.5.0-rc1 for this project. While everything seems to be functioning fine, I am facing a problem with incorpor ...
Looking to pass an i18n translate service key as a parameter function on an HTML component. Attempted the following, but instead of getting the text, it's returning the key value. Created a variable assigned with the title in the component.ts file. ...
tag, I have created an API parent class where all the necessary methods are implemented for server communication. The ApiService class is injected with Http and MdSnackBar services to handle HTTP requests and display snack bar messages. The get() method ...
Is there a way to delay the subscribe function until my logic is complete and the transform method has updated the keys object? transform(value: any, args:string) : any { let keys = []; this.http.get('src/app/enum-data/enum.json').subsc ...
Manipulating the DOM programmatically is recommended using Angular's Renderer2. Within my directive, I extract some text from el.nativeElement.innerText, modify it, and aim to append it to my element: const text = renderer.createText(`${el.innerTex ...
I attempted to test out a couple of templates which turned out to be unsuccessful: https://github.com/asadsahi/AspNetCoreSpa https://github.com/MarkPieszak/aspnetcore-angular2-universal Unfortunately, neither of them worked properly for me. I'm cu ...
Currently encountering an issue while trying to integrate firebase-admin into my angular project. Despite my efforts, I am unable to resolve the error that keeps popping up (refer to the screenshot below). https://i.stack.imgur.com/kdCoo.png I attempted ...
I have a unique challenge where I am trying to style a checkbox as a button by placing it inside its label. <label> <input type="checkbox" name="..."> </label> My goal is to toggle the parent label's class based on whether the che ...
Im currently working on developing a unique custom validator for the datepicker feature within a reactive form group. Within my code file, specifically the .ts file: form: FormGroup; constructor( private fb: FormBuilder, ...