Software architect. Web Development, build apps with Angular, TypeScript, JavaScript, and NestJS
Reading Time: 4 minutesIntroduction I wrote the simple Pokemon application in Angular 15 and RxJS to display image URLs of a specific Pokemon. In this use case, I would like to replace RxJS with Angular signals to simplify reactive codes. When code refactoring completes, ngOnInit method does not have any RxJs code and can delete. Moreover, ViewChild is … Read more
Reading Time: 3 minutesIntroduction This post wants to illustrate how to use switchMap operator to cancel previous HTTP requests and retrieve the latest Pokemon by an id. It is an important technique to preserve scarce network resource on a device such as mobile phone that has limited data plan. It also improves performance because the application does not … Read more
Reading Time: 4 minutesIntroduction This post wants to illustrate how powerful RxJS is when building a reactive user interface in Angular. The application is consisted of a group of buttons that can increment and decrement Pokemon id. When button click occurs, the observable emits the new id and renders the images of the new Pokemon. Bootstrap AppComponent In … Read more
Reading Time: 4 minutesIntroduction This is day 20 of Wes Bos’s JavaScript 30 challenge where I build a speech detection application using RxJS, Angular standalone components and Web Speech API. Angular not only can call it’s own APIs to render components but it can also interact with Web Speech API to guess what I spoke in English and … Read more
Reading Time: 7 minutesIntroduction This is day 29 of Wes Bos’s JavaScript 30 challenge where I build a countdown timer using RxJS, standalone components and standalone directive in Angular 15. Create a new Angular project Bootstrap AppComponent First, I convert AppComponent into standalone component such that I can bootstrap AppComponent and inject providers in main.ts. In Component decorator, … Read more
Reading Time: 5 minutesIntroduction This is day 6 of Wes Bos’s JavaScript 30 challenge where I create real-time search input box to filter out cities and states in the USA. This is a challenge for me because I had to rewrite the original real-time search using Angular and adopting the styles of the framework. In the tutorial, I … Read more
Reading Time: 4 minutesIntroduction This is day 2 of Wes Bos’s JavaScript 30 challenge where I create an analog clock that displays the current time of the day. In the tutorial, I created the components using RxJS, custom operators, Angular standalone components and removed the NgModules. In this blog post, I describe how to create an observable that … Read more
Reading Time: 7 minutesIntroduction This is day 1 of Wes Bos’s JavaScript 30 challenge where I create a drum kit to play sounds when keys are pressed. In the tutorial, I created the components using RxJS, Angular standalone components and removed the NgModules. In this blog post, I describe how the drum component (parent) uses RxJS fromEvent to … Read more