OS X开发.第一章,1.14, NSStepper

1.14 NSStepper
NSStepper是Cocoa中提供的步进器控件。每次控件的点击事件对应着值增加或减少。NSStepper还可与NSTextField等控件使用协议来完成实时事件回调。

1.14.1 基本声明

class WidgetController: NSViewController{
    
    
    
    var mView: NSView!

    var stepper: NSStepper!
  
    override func loadView() {
    
    
        self.view = NSView(frame: NSRect(x: 0, y: 0, width: 500, height: 300))
    }
 
    private func initView(){
    
    
        mView = NSView(frame: NSRect(x: 0, y: 0, width: self.view.frame.width, height: self.view.frame.height))
        
        stepper = NSStepper()
        stepper.frame = NSRect(x: self.view.frame.width / 2, y: 175, width: 25, height: 27)
        stepper.maxValue = 10
        stepper.minValue = 0
        stepper.increment = 1
        stepper.intValue = 3
        stepper.target = self
        stepper.action = #selector(stepperListener)
        
        self.view.addSubview(stepper)
    }
    
    private func initConfig(){
    
    
        self.title = "NSWidget-Family"
    }

    override func viewDidLoad() {
    
    
        super.viewDidLoad()
        // Do view setup here.
        
        initView()
        initConfig()
    }

    @objc func stepperListener(){
    
    
        print("------> STEPPER VALUE:\(stepper.intValue)")
    }
}

说明：maxValue决定了最大值，minValue决定了最小值，increment决定每次递增值，intValue可用于当前值的获取与设置。

运行图：