每次打开网易邮箱大师进来第一个界面就是解锁，这种设计很好的保护用户的隐私。手势解锁也是一种很好的密码方式，今天小编就介绍一下这个手势解锁。
先看下效果，我在网易邮箱大师的bandle里没有找到解锁相关的图片，感觉有可能是自己画的，这里我的图片是东凑西凑的，大家凑合看吧。

效果

思路

创建按钮

  func initButtons() {
        
        let btnW: CGFloat = 80
        let rowCount: CGFloat = 3
        let gap = (self.frame.width - btnW * rowCount) / (rowCount + 1)
        for i in 0 ..< 9 {
            let list = CGFloat(i % 3 ) // 列
            let row = CGFloat( i / 3 ) // 行
            let button = UIButton()
            button.frame = CGRectMake((btnW + gap) * list + gap, (btnW + gap) * row + 20 + topLabel.frame.maxY , btnW, btnW)
            button.tag = i
            button.setBackgroundImage(UIImage(named: "handle_normal"), forState: .Normal)
            button.setBackgroundImage(UIImage(named: "handle_selected"), forState: .Selected)
            button.userInteractionEnabled = false
            self.addSubview(button)
        }
        
    }

设置起点和按钮选中状态

  override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        
        guard result else {
            return
        }
        
        let point = pointWithTouch(touches)
        if let btn = buttonWithPoint(point) {
            if !btn.selected {
                btn.selected = true
                buttons.append(btn)
            }
        }
    }

移动中添加轨迹上的按钮到数组，并且不能重复添加，最后调用self.setNeedsDisplay()绘制轨迹

   override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
        guard result else {
            return
        }
        let point = pointWithTouch(touches)
        movePoint = point
        if let btn = buttonWithPoint(point) {
            if !btn.selected {
                btn.selected = true
                if !buttons.contains(btn) {
                    buttons.append(btn)
                }
            }
        }
        self.setNeedsDisplay()
    }

结束后记录按钮的顺序，并保存到本地，最后清空数组重新绘制一下

    override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
        guard result else {
            return
        }
        var str = ""
        for button in buttons {
            button.selected = false
            str += String(button.tag)
        }
        
        if handleResult(str) {
            result = true
            buttons.removeAll()
            self.setNeedsDisplay()
            handleBlock?(result: true)
        }else {
            for button in buttons {
                button.setBackgroundImage(UIImage(named: "handle_warning"), forState: .Normal)
            }
            result = false
            self.setNeedsDisplay()
            addAnimation()
            dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
                Int64(2.0 * Double(NSEC_PER_SEC))), dispatch_get_main_queue()) { () -> Void in
                    self.result = true
                    for button in self.buttons {
                        button.setBackgroundImage(UIImage(named: "handle_normal"), forState: .Normal)
                    }
                    self.buttons.removeAll()
                    self.setNeedsDisplay()
            }
            handleBlock?(result: false)
        }
    }

drawRect方法主要是绘制轨迹和设置按钮状态

    // 绘制轨迹
    override func drawRect(rect: CGRect) {
        if self.buttons.count == 0 {
            return
        }
        let path = UIBezierPath()
        for i in 0 ..< self.buttons.count {
            let button = buttons[i]
            if i == 0 {
                path.moveToPoint(button.center)
            }else {
                path.addLineToPoint(button.center)
            }
        }
        path.addLineToPoint(movePoint)
        path.lineWidth = 8
        if result {
            UIColor.greenColor().set()
        }else {
            UIColor.redColor().set()
        }
        path.lineJoinStyle = .Round
        path.stroke()
    }

以上是主要代码，欢迎大家指出错误
在这里下载代码，欢迎大家Star。