Adventures of an Android Developer in iOS Land

What happens when a seasoned Android developer finds herself having to learn iOS from the beginning over the course of a few months? This survival guide will discuss lessons learned, differences in developing in the two platforms, and tips and resources to help you transition from Android to iOS development.

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1. Adventures of an Android Developer in iOS Land An OS Survival Guide Yun Cheng
3. Guide to the guide Protip! Helpful links! Just me ranting...
4. XCode
5. Getting XCode Don’t download from App Store: Prevent accidental upgrades that you’re not ready for Install any version side-by-side you want Download from https://developer.apple.com/downloads/. Rename additional downloads.
6. Opening your project Open the .xcworkspace, not the .xcodeproj
7. A workspace is a collection of projects <- Open workspace Open project -> No pods Opening your project
8. XCode vs Android Studio Can’t navigate from Activity to layout Refactoring No safe delete feature Autocomplete Find matching brace Double click on brace to find its match. Be prepared to search in path (cmd+shift+F) a lot
9. Stuff you already know
10. Swift Optionals Know when to use • optional chaining • if let • guard let https://docs.swift.org/swift-book/LanguageGuide/TheBasic s.html#ID330 https://thatthinginswift.com/guard-statement-swift/
11. Lifecycle Methods onCreate onStart/onResume onPause onStop onDestroy viewDidLoad viewWillAppear viewWillDisappear viewDidDisappear
12. Protocols (i.e. interfaces) UIKit classes use delegates (e.g. UITableViewDelegate, UIPickerViewDelegate, UICollectionViewDelegate, etc) class MyViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource { //Override methods for UIPickerViewDelegate } class MyActivity : AppCompatActivity(), NumberPicker.OnValueChangeListener { //Override methods for NumberPicker.OnValueChangeListener }
13. Protocols (i.e. interfaces) cont. VC1 The delegate pattern in iOS is just using interfaces! VC1 : VC2Delegate { override func doTheThing(s: String) {} } v2Delegate.doTheThing(“MyValue”) Intent data = new Intent(); data.putExtra("myKey","myValue"); setResult(RESULT_OK,data); finish(); VC2
14. Layouts
15. Android Studio - visual layout editor vs xml Layout editor xml
16. Interface Builder Drag and drop xib files Storyboards - Can cover multiple screens - Navigation
18. Interface Builder 1) Hides information 2) Merge conflicts 3) Hard to review PRs Limit the scope of your storyboards!
19. Coding
20. Use Swift Cleaner syntax Type inference No need to create header files http://goshdarnblocksyntax.com http://goshdarnclosuresyntax.com
21. Swift Objective C interoperability Access ObjC in Swift: RunkeeperPro-Bridging-Header.h
22. Swift Objective C interoperability Access Swift in ObjC: Add @objc annotation to Swift method or class Add #import "Runkeeper-Swift.h" to top of ObjC file https://medium.com/@JoyceMatos/mix-and-match-objecti ve-c-and-swift-c6bceb7f81f3
23. Swift Objective C interoperability @objc static func launchAppOrStore(schemeString: String, appStore storeAppString: String) { ... } #import "Runkeeper-Swift.h" [[UrlOpener init] launchAppOrStoreWithSchemeString:(NSString * _Nonnull)kAsicsStudioScheme appStore:(NSString * _Nonnull)kAsicsStudioAppStoreUrl]; UrlOpener.swift : Invoke in ObjC:
24. Swift Objective C interoperability @objc static func launchAppOrStore(schemeString: String, appStore storeAppString: String) { ... } #import "Runkeeper-Swift.h" [[UrlOpener init] launchAppOrStoreWithSchemeString:(NSString * _Nonnull)kAsicsStudioScheme appStore:(NSString * _Nonnull)kAsicsStudioAppStoreUrl]; cmd+click on Runkeeper-Swift.h import statement to see renamed methods UrlOpener.swift: Invoke in ObjC:
25. Debugging Don’t use the variables view: -Not good with optional binding: if let nonOptionalThing = optionalThing {...} -Any thing derived from parent class doesn’t have those properties Use the lldb console to debug: po <object to inspect>
26. Libraries
27. CocoaPods Gradle equivalent Podfile Pods folder https://guides.cocoapods.org/using/pod-install-vs-update.ht ml
28. Mocking Reflection is not allowed in Swift No Mockito equivalent in Swift class MockRunningPacksManager: RunningPacksManager {} https://github.com/Brightify/Cuckoo https://www.swiftbysundell.com/posts/mocking-in-swift
29. After you’ve finished coding
30. Provisioning profiles Adds specific device IDs to a list of ones allowed to developer test your app TestFlight Don’t press fix it button for provisioning “Seek help ” - Jamie Hagemeister
31. Regression testing Test on a fewer devices and fewer OS High adoption rate of new versions of the OS
32. Submitting to App Store Must get Apple approval Takes about a day
33. You survived! @yuncheng13