Book Image

React Native By Example

By : Richard Kho
Book Image

React Native By Example

By: Richard Kho

Overview of this book

React Native's ability to build performant mobile applications with JavaScript has resulted in its popularity amongst developers. Developers now have the luxury to create incredible mobile experiences that look and feel native to their platforms with the comfort of a well-known language and the popular React.js library. This book will show you how to build your own native mobile applications for the iOS and Android platforms while leveraging the finesse and simplicity of JavaScript and React. Throughout the book you will build three projects, each of increasing complexity. You will also link up with the third-party Facebook SDK, convert an app to support the Redux architecture, and learn the process involved in making your apps available for sale on the iOS App Store and Google Play. At the end of this book, you will have learned and implemented a wide breadth of core APIs and components found in the React Native framework that are necessary in creating great mobile experiences.
Table of Contents (17 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback

Creating a login prompt

The first thing we should do is think about how our app will behave. When it's launched, we should check for an available access token using the FBSDK AccessToken API. If it's not available, then our user isn't logged in and we should show them the Log In button, just like we required a budget in our previous project, Expense.

If/when the user is logged in, we should grab their feed data, load it into the component state, and then log it to the console to show that we have it.

The first thing we should do is modify the App component so that:

  • On the componentWillMount event, we use the AccessToken API's getCurrentAccessToken method to check and see whether the user is logged in.
    • If the user is not logged in, we should alert the user that they are not logged in. In the next section, we will replace this part with the login screen that we will create.
    • If the user is logged in, we should call the getFeed method of graphMethods.
  • Also, it should no longer render the LoginButton...