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Monday, 12 February, 2018 UTC
Testing Reducers in NGRX Store
Next in this series, we’re going to learn how to test Reducers in NGRX Store. In the previous testing post we explored Testing Actions. As we know, Reducers are just pure functions. This makes it extremely easy to test your reducers - which control state ... moreFriday, 9 February, 2018 UTC
Testing Actions in NGRX Store
In this small NGRX Store testing series, we’re going to learn how to test Actions, Reducers and Selectors. Let’s begin with Actions, of more specifically Action Creators and how to test them. Table of contents Testing Actions What we’ll test Spec File ... moreThursday, 18 January, 2018 UTC
Angular Classes with NgClass
With Angular, we have many approaches to adding, removing, toggling classes. We can choose single classes and bind a property, or we can use the awesome NgClass directive from Angular. In this post, we’ll explore class bindings, and also Angular’s NgClass ... moreSunday, 14 January, 2018 UTC
Typing Arrays in TypeScript
There are many ways we can type a property to declare to TypeScript something is an array, or contains an array of “something”. We have generic types, array types and type assertions. For the purposes of this article, we’ll simply use a TypeScript class ... moreSaturday, 13 January, 2018 UTC
Step by Step Custom Pipes in Angular
Angular has many Pipes built-in, but they only take us so far. Ideally we’d like to extend our applications by creating custom Pipes. Custom Pipes (previously Filters in AngularJS) allow us to essentially create a pure function, which accepts an input ... moreFriday, 12 January, 2018 UTC
Handling Observables with NgIf and the Async Pipe
Dealing with async operations with the async pipe takes care of subscribing to Observable streams/async stuff like Promises for us. There are a few common gotchas when dealing with purely cold Observables that somewhat pull in data (over perhaps, Http). ... moreThursday, 11 January, 2018 UTC
Angular's NgIf, Else, Then - Explained
Using the ngIf directive allows us to simply toggle content based on a conditional. But is it as simple as we think? Not quite, the directive has a heap of helpful syntaxes that can help us deal with conditionals far better, and also asynchronous objects ... moreTuesday, 9 January, 2018 UTC
Introduction to TypeScript
Since its inception, JavaScript has experienced monumental growth - especially in recent years. The language has expanded its application domain far beyond the browser. It is now used to power backends, create hybrid mobile applications, architect cloud ... moreFriday, 22 December, 2017 UTC
Classes vs Interfaces in TypeScript
Classes and interfaces are powerful structures that facilitate not just object-oriented programming but also type-checking in TypeScript. A class is a blueprint from which we can create objects that share the same configuration - properties and methods. ... moreWednesday, 20 December, 2017 UTC
NGRX Store: Understanding State Selectors
Selectors are pure functions that take slices of state as arguments and return some state data that we can pass to our components. To better understand what selectors are and what they do, it helps see ngrx state as a data structure - a tree that can ... moreSaturday, 16 December, 2017 UTC
NGRX Store: Actions versus Action Creators
Actions in the Redux paradigm are the initiators of the one-way dataflow process for state management. Once an action is triggered, or rather dispatched, the process is kicked off for new state to be composed - which is typically composed by the payload ... moreThursday, 14 December, 2017 UTC
Finally understand Redux by building your own Store
Redux is an interesting pattern, and at its core a very simple one - but why does it feel complex to understand? In this post, we’re going to dive into Redux by assembling our own custom Store, written in TypeScript. Table of contents Terminology Actions ... moreTuesday, 26 September, 2017 UTC
Exploring set(), get() and Object.defineProperty() in TypeScript
When working with Javascript or TypeScript, you may have seen the set and get keywords being thrown around in various blogs or codebases - and they’re extremely useful for parsing or modifying data that’s about to be set on a particular object. In this ... moreThursday, 24 August, 2017 UTC
Preloading ngrx/store with Route Guards
Using ngrx/store (and some love for ngrx/effects) is definitely a great step for my productivity when managing state in Angular, and I want to share a small setup that’ll allow you to preload data as normal with a Route Guard. The interesting thing is ... moreMonday, 17 July, 2017 UTC
Lazy loading: code splitting NgModules with Webpack
Let’s talk about code splitting in Angular, lazy-loading and a sprinkle of Webpack. Code splitting allows us to essentially break our codebase down into smaller chunks and serve those chunks on demand, which we call “lazy loading”. So, let’s learn how ... moreWednesday, 17 May, 2017 UTC
RxJS: Observables, observers and operators introduction
RxJS is an incredible tool for reactive programming, and today we’re going to dive a little deeper into what Observables and observers are - as well as learn how to create our own operators. If you’ve used RxJS before and want to understand some of the ... moreTuesday, 11 April, 2017 UTC
Introducing ngErrors, declarative form errors for Angular
I’ve been working on an open source project to bring better validation to Angular’s reactive forms. In this post we’ll take a look at how to use it, why I created it and the problems it aims to solve. Go to GitHub repo Table of contents What is ngErrors? ... moreMonday, 6 March, 2017 UTC
Angular constructor versus ngOnInit
Angular has many lifecycle hooks, as well as a constructor . In this post, we’ll quickly cover the differences between the ngOnInit lifecycle hook which has been the source of some confusion for those getting started with Angular. So, why do we need ... moreWednesday, 22 February, 2017 UTC
Getting started with Angular's component Router
Angular’s component router acts as the main hub of any application, it loads the relevant components relevant to the route requested, as well as dealing with fetching the relevant data for that particular route. This allows us to control different routes, ... moreWednesday, 1 February, 2017 UTC
Angular ngFor, <template> and the compiler
Angular ngFor is a built-in Directive that allows us to iterate over a collection. This collection is typically an array, however can be “array-like”. To demonstrate this, we’ll be using Rx.Observable.of() to initialise our collection with an Observable ... moreThursday, 26 January, 2017 UTC
A deep dive on Angular decorators
Decorators are a core concept when developing with Angular 2 and above. There’s also an official TC39 proposal, currently at Stage-2, so expect decorators to become a core language feature soon in JavaScript as well. Back to Angular, the internal codebase ... moreTuesday, 24 January, 2017 UTC
Mastering Angular dependency injection with @Inject, @Injectable, tokens and providers
Providers in Angular are key to how we develop our applications, and injecting dependencies can be done in various ways. In this post, we’re going to debunk some terminology behind the @Inject() and @Injectable() decorators and explore the use cases ... moreFriday, 20 January, 2017 UTC
Should you learn Angular 1.x or 2?
A question that I’m frequently asked, “should I learn Angular 1 or 2?”. I hope this post offers some insight, help and guidance into answering that question for you. No one can answer it directly, because it’s specific to yourself, so here are some thoughts. ... moreTuesday, 20 December, 2016 UTC
TypeScript: the missing introduction
The following is a guest post by James Henry (@MrJamesHenry). I am a member of the ESLint Core Team, and a TypeScript evangelist. I am working with Todd on UltimateAngular to bring you more award-winning Angular and TypeScript courses. The purpose of ... moreWednesday, 14 December, 2016 UTC
Building Tesla's battery range calculator with Angular 2 reactive forms
In this epic tutorial, we’re going to build some advanced Angular 2 components that rebuild Tesla’s battery range calculator and then compile it to AoT and deploy on GitHub pages. We’ll be using the reactive forms API as well and building custom form ... moreTuesday, 6 December, 2016 UTC
Angular 1.6 is here, this is what you need to know
Angular 1.6 is in the final release candidate stage and is coming this week. Here’s the low down on what to expect for the component method changes as well as an amazing new ngModelOptions feature. The purpose of this article is to focus on the most ... moreFriday, 18 November, 2016 UTC
Dynamic page titles in Angular 2 with router events
Updating page titles in Angular 1.x was a little problematic and typically was done via a global $rootScope property that listened for route change events to fetch the current route and map across a static page title. In Angular 2, the solution is far ... moreWednesday, 16 November, 2016 UTC
Updating Angular 2 Forms with patchValue or setValue
Setting model values in Angular 2 can be done in a few different ways, however with reactive forms things are extremely easy to do with the new form APIs. In this post we’ll dig a little deeper as to the differences between patchValue and setValue in ... moreThursday, 10 November, 2016 UTC
Please stop worrying about Angular 3
Another Angular version planned already? Whaaaat? Didn’t Angular 2 just ship? Why Angular 3? What? Why? First off, there is no massive rewrite, and won’t be for Angular 3. Secondly, let me explain the future of Angular 2 and what Angular 3, Angular 4 ... moreFriday, 4 November, 2016 UTC