A JavaScript framework for creating ambitious web applications.

ember

Learn Ember

In this lesson we will create an `updateContent` method that sets the value of our `content` property to the current epoch timestamp. We need to call `toString()` on the `Date.now()` method in order to make TypeScript happy.

```
updateContent() {
  this.content = Date.now().toString()
}
```

We create a constructor that takes the options parameter, call `super(options)` and call into our `this.updateContent()` method.

```
constructor(options) {
  super(options)
  this.updateContent()
}
```

When we refresh our page we can see that the value of `content` is set to the epoch timestamp. 

To make the content really dynamic we use `setInterval()` to call into `updateContent` each second: `setInterval(() => this.updateContent(), 1000)`.

When we save our file we see that our content does not get updated anymore and when we check the console we see that we get an error telling us that: The 'content' property on the my-component component was changed after it had been rendered. The error also informs us that we should Use the @tracked decorator to mark this as a tracked property.

We add the @tracked decorator to our property, we import tracked from @glimmer/component and we refresh the page. We verify that `content` gets updated each second.

We change our `updateContent` to add our the timestamp to the array. When we use `this.items.push(this.content)` to achieve this we see that the list does not get updated. This is because the `@tracked` decorator only tracks the re-assignment of properties.

The way to get this working is by re-assigning our `items` array inside `updateContent`. We assign a new array, de-structure the current items array and add the new content.

```
this.items = [...this.items, this.content]
```



Use dynamic data in a GlimmerJS component

In this lesson we will use the ember cli to generate a new component. Running `ember g glimmer-component my-component` generates the template and component class. We change the content of our component and add it to the main template in order to show it on the page.

Create a new GlimmerJS component

In this lesson we will add a variable called `content` to our component class, initialize it as a string and display the variable in our class using the double curly braces syntax, which is the handlebars expression for expressions, `{ {content }}`. 

After this we create a new class variable called `items`, initialize it as an array with strings. To display this list in our template we add a `<ul></ul>` and inside this unordered list we use the handlebars `each` helper to display the list items.

And inside our each statement we will print a `<li>` tag and render `{{ item}}` inside it.

```
<ul>
  {{#each items key="@index" as |item| }}
    <li>{{item}}</li> 
  {{/each}}
</ul>
```



Use template variables in a GlimmerJS component

[GlimmerJS](https://glimmerjs.com/) is a UI component library built by the Ember.js team. It is fast and lightweight and uses a combination of TypeScript and Handlebars to build the components.   

In this lesson we will use the Ember CLI to initialize a new GlimmerJS project.

We will start by installing Ember CLI globally by running `npm install -g ember-cli/ember-cli`.

Next we will use the `ember` command to create our new project by running `ember new egghead-glimmer -b @glimmer/blueprint` . 

When our project is created we `cd` into the project directory and start the development server. We will view the page in the browser and change the base template.

Initialize a project using Glimmer.js

<p>Today Joel catches up with Iheanyi Ekechukwu. Iheanyi is a Product Engineer currently working at DigitalOcean. He previously worked at IBM on Watson. They also talk about Iheanyi's education, stack, and side projects</p><p>Iheanyi started out majoring in Computer Engineering, but switched to Computer Science after he figured out hardware just wasn't for him. He now lives and works in Brooklyn and spends most of his time coding (though he always brings his design skills to the table).</p><p>Iheanyi's design comes from a dual degree program at Notre Dame, the college where he graduated. He noticed a lot of subpar interfaces coming from pure programmers, and he was frustrated with that, so he took his school's opportunity to learn design and apply it to his work. Even if he isn't a designer, he uses his skills daily to communicate with designers and make whatever he works on that much better.</p><p>Iheanyi started using Ember back during college. He was frustrated by his school's class search interface, and he set out to improve it. Ember and Rails were like a match made in heaven for him, Ember having been authored by ex-Rails core team member, Yehuda Katz.</p><p>Joel discusses with Iheanyi what he's currently using in his work. They get into GO, and how Iheanyi has enjoyed working with a statically typed language when doing back-end work. Not having to worry about full test coverage when refactoring has been great!</p><p>Lastly, they talk about the various side projects Iheanyi has going. Such as Interface Lovers, a blog where top designers are interviewed and share their work music playlists. Also, Seeker, a job-board app that allows you to connect your strip account to it and have companies submit jobs.</p><hr /><h3>Transcript</h3><p><a href="https://egghead.simplecast.com/episodes/47aebd17/transcript">"Iheanyi Ekechukwu on education, programming, and managing side projects" Transcript</a></p><h3>Resources</h3><ul><li><a href="https://seeker.company">seeker</a></li><li><a href="https://interfacelovers.com/">Interface Lovers</a></li><li><a href="http://creative.black/">Creative Black</a></li><li><a href="https://www.ibmchefwatson.com/">Chef Watson</a></li></ul><h3>Iheanyi Ekechukwu</h3><ul><li><a href="https://iheanyi.com/">Website</a></li><li><a href="http://www.twoblacknerds.com/">Podcast</a></li><li><a href="https://twitter.com/kwuchu">Twitter</a></li><li><a href="https://github.com/iheanyi">Github</a></li><li><a href="https://egghead.io/instructors/iheanyi-ekechukwu">egghead.io</a></li></ul><h3>Joel Hooks:</h3><ul><li><a href="https://twitter.com/jhooks">Twitter</a></li><li><a href="https://joelhooks.com/">Website</a></li></ul>

Today Joel catches up with Iheanyi Ekechukwu. Iheanyi is a Product Engineer currently working at DigitalOcean. He previously worked at IBM on Watson. They also talk about Iheanyi's education, stack, and side projects

Topics

Instructors

Content Type

Ember.js

Use dynamic data in a GlimmerJS component

Create a new GlimmerJS component

Use template variables in a GlimmerJS component

Initialize a project using Glimmer.js

Iheanyi Ekechukwu on education, programming, and managing side projects