josephzhang23

import UIKit

func sizeHeightWithText(labelText: String,
                        fontSize: CGFloat,
                        textAttributes: [String : AnyObject]) -> CGRect {
    
    return labelText.boundingRect(
        with: CGSize(width:fontSize, height:480),
        options: NSStringDrawingOptions.usesLineFragmentOrigin,
        attributes: textAttributes, context: nil)

josephzhang23

let fontSize: CGFloat = 22.0

func sizeHeightWithText(labelText: NSString,
    fontSize: CGFloat,
    textAttributes: [String : Any]) -> CGRect {
        
    return labelText.boundingRect(
        with: CGSize(width:fontSize, height:480),
            options: NSStringDrawingOptions.usesLineFragmentOrigin,
            attributes: textAttributes, context: nil)

josephzhang23

func swapTwoValues<Joseph>(_ a: inout Joseph, _ b: inout Joseph) {
    let temporaryA = a
    a = b
    b = temporaryA
}

var someInt = 3
var anotherInt = 107
swapTwoValues(&someInt, &anotherInt)
print("someInt 现在是\(someInt)，anotherInt 现在是 \(anotherInt)")

josephzhang23

func swapTwoInts(_ a: inout Int, _ b: inout Int) {
    let temporaryA = a
    a = b
    b = temporaryA
}

var someInt = 3
var anotherInt = 107
swapTwoInts(&someInt, &anotherInt)
print("someInt 现在是 \(someInt)，anotherInt 现在是 \(anotherInt)")

josephzhang23

protocol ManagedObjectContextSettable: class {
    var managedObjectContext: NSManagedObjectContext! { get set }
}

josephzhang23

let nickName: String? = nil
let fullName: String = "John Appleseed"
let informalGreeting = "Hi \(nickName ?? fullName)"

josephzhang23

func objectAtIndexPath(indexPath: NSIndexPath) -> Object {
    guard let result = fetchedResultsController.objectAtIndexPath(indexPath)
        as? Object else
    {
        fatalError("Unexpected object at \(indexPath)")
    }
    return result
}

josephzhang23

-(void) callMe { 
  //...
}
-(void) callMeWithParam:(id)obj {
  //...
  
 }
 
 SEL someMethod = @selector(callMe);
 SEL anotherMethod = @selector(callMeWithParam:);

josephzhang23

func addTo(_ adder: Int) -> (Int) -> Int {
    return {
        num in
        return num + adder
    }
}

let addTwo = addTo(2) //addTwo:Int -> Int
let result = addTwo(6) //result = 8

josephzhang23

override func didReceiveMemoryWarning() {
  super.didReceiveMemoryWarning()
  
  // 在这里销毁所有可以被重建的资源
}