Book Image

Swift 2 By Example

By : Giordano Scalzo
Book Image

Swift 2 By Example

By: Giordano Scalzo

Overview of this book

Swift is no longer the unripe language it was when launched by Apple at WWDC14, now it’s a powerful and ready-for-production programming language that has empowered most new released apps. Swift is a user-friendly language with a smooth learning curve; it is safe, robust, and really flexible. Swift 2 is more powerful than ever; it introduces new ways to solve old problems, more robust error handling, and a new programming paradigm that favours composition over inheritance. Swift 2 by Example is a fast-paced, practical guide to help you learn how to develop iOS apps using Swift. Through the development of seven different iOS apps and one server app, you’ll find out how to use either the right feature of the language or the right tool to solve a given problem. We begin by introducing you to the latest features of Swift 2, further kick-starting your app development journey by building a guessing game app, followed by a memory game. It doesn’t end there, with a few more apps in store for you: a to-do list, a beautiful weather app, two games: Flappy Swift and Cube Runner, and finally an ecommerce app to top everything off. By the end of the book, you’ll be able to build well-designed apps, effectively use AutoLayout, develop videogames, and build server apps.
Table of Contents (18 chapters)
Swift 2 By Example
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Free Chapter
1
Welcome to the World of Swift
2
Building a Guess the Number App
Index

Downloading the background image


Before moving on to downloading the actual forecast, we'll introduce the topic of networking downloading a geo-localized background image.

Searching in Flickr

To get an image, we'll use the API of Flickr, a famous image-hosting website, using a convenient Pod. First of all, we override the viewWillAppear function in PrettyWeatherApp so that a new image will be downloaded every time View Controller appears:

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    
    let lat:Double = 48.8567
    let lon:Double = 2.3508

    FlickrDatastore().retrieveImageAtLat(lat, lon: lon){ image in
        self.render(image)
    }
}

To implement the searching feature, we set a dummy value using the coordinates of Paris. Then, we create a new file named FlickrDatastore:

import FlickrKit

class FlickrDatastore {
    private let OBJECTIVE_FLICKR_API_KEY = "CREATE_API_KEY"
    private let OBJECTIVE_FLICKR_API_SHARED_SECRET = "CREATE_SHARED_SECRET"
...