It simplifies user interactions and makes interfaces fully responsive to any data source changes. Knockout provides a simple two-way binding mechanism to link a data model to an UI, thus making synchronization between them a breeze. As you will see if you want to get the most benefits you should use them together. In this tutorial, we start with the core concepts and capabilities of Knockout. Before we go through the code examples, first you may need to grasp some basic concepts.
In this pattern your application is split into three parts:. This can be data entered by users or JSON data fetched from a web server. A view that serves as a connector and communication layer between Model and View. It holds data and operations for manipulating this data and display it in the UI.
Every time when data model is changed corresponded UI parts updates, reflecting these changes. View Model in your application is represented by JavaScript code. A view that refers to all UI elements in your application.
It is a representation of the structure and appearance for given UI. The view is responsible for displaying data and accepting user input. Declarative Bindings: These allow you to connect parts of your UI to your data model in a simple and convenient way.
With declarative bindings even if you change the DOM all bound pieces stay connected. Dependency Tracking: Thankfully to the bindings and special type of variables called observables every time when your model data has changed all parts associated with it automatically being updated. No need to worry about adding event handlers and listeners. All that extra work is performed internally by Knockout and observables, which notify listeners when underlying values have changed. Templating: This comes in handy when your application becomes more complex and you need a way to display a rich structure of view model data, thus keeping your code simple.
Knockout has a native, built-in template engine which you can use right away. But if you want, a third-party template engine, like jquery.
When we go through the tutorial and the code examples everything will become clearer. To keep your code separate from your presentation is better to create a JavaScript file to hold all application code. And because we will use jQuery in some cases you need to reference it too. This is considered as best practice but for training purpose and to make things easier you can put the JavaScript code in the same document by either including it in the head tag or place it bellow your markup.
So in order to take effect Knockout has to be activated by inserting ko. Also if you use external JavaScript file or your script is placed in the head tag of your document you need to wrap the Knockout code in a jQuery ready function in order to work properly.
Here is the basic template to start:. Calling the ko. You can even provide a DOM element if you only want to bind this view model to one part of your overall UI. The first parameter says what view model object you want to use with the declarative bindings it activates. The second parameter is optional and it defines which part of the document you want to search for data-bind attributes. Upload eBook. Privacy Policy.
New eBooks. Search Engine. Learn how to knock out your next app in no time with KnockoutJS. Overview Learn how to develop a deployable app as the author walks you through each step Understand how to customize and extend KnockoutJS to take your app to the next level Great examples showing how KnockoutJS can simplify your code and make it more robust In Detail Knockout is a JavaScript library that allows developers to create rich, responsive display and editor user interfaces with a clean underlying data model.
The "KnockoutJS Starter" guide pulls from real-world professional app development experiences and brings those to readers in a way that is easy to understand. It works through practical examples in order to showcase both the power of the KnockoutJS library, and illustrate best practices when developing apps.
The guide starts off by working through a real-life app, and then breaks down the patterns and components for the reader to easily understand and reference. Working through the examples, the reader will see strategies for building out an easy-to-maintain application structure and grasp best-practices for separating business logic from user interface code.
Concepts such as retrieving data, building custom user-interface components, and avoiding common mistakes are explained in detail so that the reader can quickly become a pro. All in all the "KnockoutJS Starter" guide will empower readers with the knowledge they need to take their development skills to another level with KnockoutJS. What you will learn from this book Learn about the Model-View-ViewModel pattern with practical examples Find out why data binding is so useful when building applications Explore the core library objects and components that KnockoutJS has to offer Discover how to leverage KnockoutJS to solve most of your common development needs Build practical project structures and learn how to organize a maintainable code base Understand how KnockoutJS's observables and bindings work under-the-hood Create your own custom bindings Practice pro debugging and development techniques Approach It's a Starter guide which will get you started quickly with the main features of KnockoutJS and take you through it.
Who this book is written for The "KnockoutJS Starter" guide is for anyone who is curious if KnockoutJS can add to their application development practice. It is written so that novice developers can easily follow along, but is advanced enough that even seasoned developers can glean useful and practical knowledge. KnockoutJS Web Development.
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