Alexander Nekrasov - Swift Recipes for iOS Developers: Real-Life Code from App Store Apps

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The answer depends on your current level of knowledge on Swift.

You know the answers? Then youre good to go!

The simplest way to try Swift code is a Playground. You can create one in Xcode instead of a project. A Playground can contain one or more files; you can declare classes, variables, constants, and functions there. Basically, its the same as a project, except that it wont compile into an executable. In a Swift Playground, you can run code without an iOS device or simulator, and youll see the content of all variables without setting breakpoints.

If youre at the beginning of your Swift learning journey, it will be better for you to type the code instead of copying and pasting it. While typing, youre actively learning.

If you know other programming languages already, it will be much easier. But even if thats not the case, Swift is not a bad option to start with.

If you already know Swift but havent written your own app yet, try to do so. Think of this: Which app would you like to have on your iPhone or iPad? It doesnt matter if such app already exists make your own version of it! You can even publish it on the App Store in the end. Unless you violate some of their rules, theres no problem in it. Make it free, get feedback from users, fix bugs, and upload updates.

You can use recipes from this book without any limitations, but dont forget that programming is more of an art than a science. Modify the code for yourself; make it yours. While its still better to read from beginning to end, its not a requirement. Be creative, find the recipes you need now, and use them. Its important that you understand what you use, and for this reason, each recipe has an explanation.

If youre an experienced developer, you can simply pick code snippets from GitHub. You know what to do. If something doesnt work for you or you know a better way of implementing a feature, send your feedback to swiftrecipes@foxicorn.com . It will be highly appreciated!

The purpose of this book is to give you good code snippets that you can use in your projects or modify for your own needs. But what is good code and whats the difference between good and bad code?

Looking at the second code snippet, a programmer (including yourself) will tell what it is instantly. And that it will work faster and consume less memory as well. Swift may optimize the first function to work without temporary variables, but it will remain a bad code nonetheless.

As you can see, even though the first code snippet works, its not readable, its not optimal, it uses an unnecessary optional variable. For such a small function, it may not be critical, but if the function was at least 1520 lines long, it would end up being nonunderstandable code, and you would end up rewriting it instead of reusing it when you need it in the future.

Well-written code doesnt require many comments. Sometimes, comments are necessary, but the code should be as self-explanatory as possible. If the code is understandable for other programmers without comments, its probably well-written code.