Swift UIButton、UIImageView、元组、流程控制、标签

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创建UIButton、UIImageView

let btn = UIButton()
btn.frame = CGRectMake(100, 100, 100, 100)
btn.backgroundColor = UIColor.redColor()
self.view.addSubview(btn)

let imageView = UIImageView()
imageView.image = UIImage(named: "image")
imageView.frame = CGRectMake(100, 200, 100, 100)
self.view.addSubview(imageView)

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元组

//类似 结构体和数组 的结合
let point = (x:10,y:20)
        
point.x//设值point.x = 30
point.y//取值
        
point.0
point.1
print(point)//(10, 20)

let (x,y) = (10,20)
let point1 = (x,y)
print("point1 \(point1)")//(10, 20)

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流程控制

for _ in 1...5{
            
     //不需要用到变量i时，用下划线_进行忽略，避免不必要的浪费
      print("111")
}

//0..<5 --- [0,5)
for i in 0..<5{
    print(i)
}

let pointa = (10,-10)
switch pointa {
case let(x,y) where x==y:
    print("x==y")
case let(x,y) where x == -y:
    print("x==-y")
default:
    print("不在这两条线上")
}

---

标签 out

out:
for _ in 1...2 {
     for _ in 1...3 {
          print("做俯卧撑")
          //break //退出本循环
          break out//退出到外面out循环
     }
     print("休息一次")
}