Book Image

Mastering Swift 2

By : Jon Hoffman
Book Image

Mastering Swift 2

By: Jon Hoffman

Overview of this book

<p><span id="description" class="sugar_field">At their Worldwide Developer’s conference (WWDC) in 2015, Apple announced Swift 2, a major update to the innovative programming language they first unveiled to the world the year before. Swift 2 features exciting enhancements to the original iteration of Swift, acting, as Apple put it themselves as “a successor to the C and Objective-C languages.” – This book demonstrates how to get the most from these new features, and gives you the skills and knowledge you need to develop dynamic iOS and OS X applications.<br /> </span></p> <p><span id="description" class="sugar_field">Learn how to harness the newest features of Swift 2 todevelop advanced applications on a wide range of platforms with this cutting-edge development guide. Exploring and demonstrating how to tackle advanced topics such as Objective-C interoperability, ARC, closures, and concurrency, you’ll develop your Swift expertise and become even more fluent in this vital and innovative language. With examples that demonstrate how to put the concepts into practice, and design patterns and best practices, you’ll be writing better iOS and OSX applications in with a new level of sophistication and control.</span></p>
Table of Contents (24 chapters)
Mastering Swift 2
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Free Chapter
1
Taking the First Steps with Swift
2
Learning about Variables, Constants, Strings, and Operators
Index

XML and manually building XML documents


Since we are unable to use the NSXMLNode, NSXMLDocument, and NSXMLElement classes in iOS projects, we generally need to manually build the XML string or use third-party libraries. This method is error-prone and it requires us to have a very good knowledge of how XML documents are built but, if we are careful, we can create simple XML documents this way.

Let's see how to manually create an XML document. For this, we will create a function named builXMLString(), which takes an array of Book objects as its only parameter. We will also create a helper class named getElementString() that will create a string representation of an XML element. The getElementString() function will accept two elements: the element name and value. Let's have a look at the following code:

func buildXMLString(books: [Book]?) -> String {
  var xmlString = ""
  if let myBooks = books {
    xmlString = "<\(DocTags.BOOKS_TAG)>"
    for book in myBooks {
      xmlString += ...