Efficient_Interactions_with_Frameworks.md

WWDC 2017

Table of Contents

• Efficient Interactions with Frameworks
  • Improvements in Foundation
  • Data
  • Bridges and how they affect your app
  • Strings, range, and text
  • Best practices & tips

Efficient Interactions with Frameworks

Session video and resources: https://developer.apple.com/videos/play/wwdc2017/244/

Improvements in Foundation

• NSCalendar
• Internet locking improvements
• NSOperation and NSOperationQueue
• Copy on write collections - return copy NSMutableArray as NSArray

Data

• Subscripting Data is faster - indices
• malloc/free is not needed Data(count:250) implements
• ranges -subdata

Bridges and how they affect your app

• Toll-free bridging
  • From a CF type to a NS Type
  • From a NS type to a CF Type
  • Zero cost at cast
  • Extra cost at usage
• Swift bridging
• Costs are on the usage
• CFArrayGetCount((CFArrayRef(array))

Strings, range, and text

• NSTextStorage -> NSMutableAttirutedString

var text = textView.textStorage.string // cost of copy
var text = textView.textStorage.mutableString // NO cost of copy <— USE THIS ONE FOR NOW (apple is working on a solution for future)

• NSAttributedString- NSRange without casting String - NSString
• NSRegularExpression - Range for UTF16-UTF8 without casting

Best practices & tips

• Autolayout practices
• Set rendering for attributed strings
• Specify alignment and writing direction if known.
• baseWritingDirection = .leftToRight
• Use clip line breaking mode