.statement h4 Live Examples p. If you want to skip to the working examples you can check out these links on Plunker. TypeScript Example or ES5 Example. .l-main-section h2#section-displaying-controller-properties Displaying controller properties p. Let's walk through how we'd display a property, a list of properties, and then conditionally show content based on state. We'll end up with a UI that looks like this: figure.image-display img(src='displaying-data-example1.png') .l-main-section h2#section-create-an-entry-point Create an entry point p Open your favorite editor and create a show-properties.html file with the content: code-example(language="html" escape="html"). p | The <display> component here acts as the site where you'll insert your application. | We'll assume a structure like this for the rest of the examples here and just focus on the parts that | are different. .l-main-section h2#section-showing-properties-with-interpolation Showing properties with interpolation p.text-body | The simple method for binding text into templates is through interpolation where you put the name of a property | inside {{ }}. p To see this working, create another file, show-properties.js, and add the following: code-tabs code-pane(language="javascript" name="ES5" format="linenums" escape="html"). // ES5 function DisplayComponent() { this.myName = "Alice"; } DisplayComponent.annotations = [ new angular.Component({ selector: "display" }), new angular.View({ template:

My name: {{ myName }}

, directives: [angular.For, angular.If] }) ]; code-pane(language="javascript" name="TypeScript" format="linenums" escape="html"). // TypeScript import {Component, View, bootstrap, For} from 'angular2/angular2'; @Component({ selector: 'display' }) @View({ template: `<p>My name: {{ myName }}</p>`, directives: [For] }) class DisplayComponent { myName: string; todos: Array<string> constructor() { this.myName = "Alice"; } } p. You've just defined a component that encompases a view and controller for the app. The view defines a template: code-example(language="html" escape="html").

My name: {{ myName }}

p. Angular will automatically pull the value of myName and insert it into the browser and update it whenever it changes without work on your part. p. One thing to notice here is that though you've written your DisplayComponent class, you haven't called new to create one anywhere. By associating your class with elements named 'display' in the DOM, Angular knows to automatically call new on DisplayComponent and bind its properties to that part of the template. p. When you're building templates, data bindings like these have access to the same scope of properties as your controller class does. Here, your class is the DisplayComponent that has just one property, myName. .callout.is-helpful header Note p. While you've used template: to specify an inline view, for larger templates you'd want to move them to a separate file and load them with templateUrl: instead. p So you can see Angular dynamically update content, add a line after code-example(language="html" escape="html").

My name: {{ myName }}

p to this: pre.prettyprint.lang-html code. <p>Current time: {{ time }}</p> p. Then give the DisplayComponent a starting value for time and a call to update time via setInterval. pre.prettyprint.lang-javascript code. setInterval(function () { this.time = (new Date()).toString(); }.bind(this), 1000); p Reload the page in your browser and you'll now see the seconds updating automatically. .l-main-section h2#Create-an-array Create an array property and use For on the view p Moving up from a single property, create an array to display as a list. code-tabs code-pane(language="javascript" name="ES5" format="linenums" escape="html"). //ES5 function DisplayComponent() { this.myName = "Alice"; this.names = ["Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } code-pane(language="javascript" name="TypeScript" format="linenums" escape="html"). //Typescript constructor() { this.myName = "Alice"; this.names = ["Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } p. You can then use this array in your template with the for directive to create copies of DOM elements with one for each item in the array. code-tabs code-pane(language="javascript" name="ES5" format="linenums"). //ES5 template: '<p>My name: {{ myName }}</p>' + '<p>Friends:</p>' + '<ul>' + '<li *for="#name of names">' + '{{ name }}' + '</li>' + '</ul>', code-pane(language="javascript" name="TypeScript" format="linenums"). //Typescript template: ` <p>My name: {{ myName }}</p> <p>Friends:</p> <ul> <li *for="#name of names"> {{ name }} </li> </ul> `, p. To make this work, you'll also need to add the angular.For directive used by the template so that Angular knows to include it: code-tabs code-pane(language="javascript" name="ES5" format="linenums"). //ES5 directives: [angular.For] code-pane(language="javascript" name="TypeScript" format="linenums"). //Typescript import {Component, View, bootstrap, For} from ... directives: [For] p Reload and you've got your list of friends! p. Again, Angular will mirror changes you make to this list over in the DOM. Add a new item and it appears in your list. Delete one and Angular deletes the <li>. Reorder items and Angular makes the corresponding reorder of the DOM list. p Let's look at the few lines that do the work again: pre.prettyprint.lang-html code. //HTML <li *for="#name of names"> {{ name }} </li> p The way to read this is: ul li. *for : create a DOM element for each item in an iterable like an array li #name : refer to individual values of the iterable as 'name' li of names : the iterable to use is called 'names' in the current controller p Using this syntax, you can build UI lists from any iterable object. .l-main-section h2#Create-a-class Create a class for the array property and inject into component p. Before we get too much further, we should mention that putting our model (array) directly in our controller isn't proper form. We should separate the concerns by having another class serve the role of model and inject it into the controller. p Make a FriendsService class to provide the model with the list of friends. pre.prettyprint.lang-javascript code. function FriendsService() { this.names = ["Alice", "Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } p. Replace the current list of friends in DisplayComponent by passing in the FriendsService and setting the list of names in DisplayComponent to the names provided by the service you passed in. pre.prettyprint.lang-javascript code. function DisplayComponent(friends) { this.myName = "Alice"; this.names = friends.names; } p And then make FriendsService available to dependency injection pre.prettyprint.lang-javascript code. DisplayComponent.annotations = [ new angular.Component({ selector: "display", injectables: [FriendsService] }), ... DisplayComponent.parameters = [[FriendsService]]; .callout.is-helpful header ES5 Note p. The dependency injection syntax here is using the low-level API and is...well...not very nice. We're working on sugaring the syntax to match the way it works in Angular 1. Expect this to change soon. .code-box pre.prettyprint.lang-javascript(data-name="es5") code. //ES5 function FriendsService() { this.names = ["Alice", "Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } function DisplayComponent(friends) { this.myName = "Alice"; this.names = friends.names; } DisplayComponent.annotations = [ new angular.Component({ selector: "display", injectables: [FriendsService] }), new angular.View({ template: '{{ myName }} <ul> <li *for="#name of names">{{ name }}</li> </ul>', directives: [angular.For, angular.If] }) ]; DisplayComponent.parameters = [[FriendsService]]; document.addEventListener("DOMContentLoaded", function() { angular.bootstrap(DisplayComponent); }); pre.prettyprint.lang-typescript(data-name="typescript") code. //TypeScript import {Component, View, bootstrap, For} from ... directives: [For] .l-main-section h2#Conditionally-displaying-data-with-If Conditionally displaying data with If p. Lastly, before we move on, let's handle showing parts of our UI conditionally with If. The If directive adds or removes elements from the DOM based on the expression you provide. p See it in action by adding a paragraph at the end of your template pre.prettyprint.lang-html code. <p *if="names.length > 3">You have many friends!</p> p You'll also need to add the If directive so Angular knows to include it. .code-box pre.prettyprint.lang-javascript(data-name="es5") code. //ES5 directives: [angular.For, angular.If] pre.prettyprint.lang-typescript(data-name="typescript") code. //Typescript import {Component, View, bootstrap, For, If} from ... directives: [For, If] p. As there are currently 5 items it the list, you'll see the message congratulating you on your many friends. Remove two items from the list, reload your browser, and see that the message no longer displays. .code-box pre.prettyprint.lang-javascript(data-name="es5") code. //ES5 function DisplayComponent() { this.myName = "Alice"; this.names = ["Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } DisplayComponent.annotations = [ new angular.Component({ selector: "display" }), new angular.View({ template: '<p>My name: {{ myName }}</p>' + '<p>Friends:</p>' + '<ul>' + '<li *for="#name of names">' + '{{ name }}' + '</li>' + '</ul>' + '<p *if="names.length > 3">You have many friends!</p>', directives: [angular.For, angular.If] }) ]; pre.prettyprint.lang-typescript(data-name="typescript") code. //TypeScript import {Component, View, bootstrap, For, If} from 'angular2/angular2'; @Component({ selector: 'display' }) @View({ template: ` <p>My name: {{ myName }}</p> <p>Friends:</p> <ul> <li *for="#name of names"> {{ name }} </li> </ul> <p *if="names.length > 3">You have many friends!</p> `, directives: [For, If] }) class DisplayComponent { myName: string; todos: Array; constructor() { this.myName = "Alice"; this.names = ["Aarav", "Martín", "Shannon", "Ariana", "Kai"]; } }