playground 正确使用姿势

playground是用于swift学习和交互简化的工具，无需编码知识即可学习，然而你需要懂得这个工具的几个地方

• 控制台程序
• UI程序
• 访问source文件

控制台应用

打开Xcode创建PlayGround工程

var str = "ttt"
print(str)

控制台效果图

在右侧即可显示结果

UI程序

• import PlaygroundSupport
• AssistentEditor

AssisentEditor在这里

let containerView = UIView(frame:CGRect(x:0.0, y:0.0, width:375.0, height:667.0))

containerView.backgroundColor = UIColor.white

let contentView = UIView(frame:CGRect(x:0, y:0, width:100, height:100))

contentView.backgroundColor = UIColor.yellow

containerView.addSubview(contentView)

contentView.center = containerView.center

UIView.animate(withDuration:0.2, animations: {
    
    contentView.transform = CGAffineTransform(scaleX:0.8, y:0.8)
    
}) { (result) in
    
    UIView.animate(withDuration:1, animations: {
        
        contentView.transform=CGAffineTransform(scaleX:4, y:4)
        
        contentView.alpha=0
        
    })
    
    
}

PlaygroundPage.current.liveView = containerView

UI效果图.jpg

访问source文件

• 打开Navigator
• 在Sources文件夹里面写入文件
• swift文件内的class需要为public包括暴露的方法，因为这里会当做你不同模块处理

打开Navigator后可以看到Sources.jpg

//只需要在playground里面加入一句话
PlaygroundPage.current.liveView=ButtonViewController()

//sources 下的swift文件  

import Foundation

import UIKit


public class ButtonViewController : UIViewController {
    
    var counter = 0
    
    var label : UILabel!
    var button : UIButton!
    var starButton : UIButton!
    
    public override func loadView() {
        
        // UI
        
        let view = UIView()
        view.backgroundColor = .white
        
        label = UILabel()
        
        button = UIButton(type: .system)
        button.setTitle("Increment", for: .normal)
        button.tintColor = .red
        button.addTarget(self, action: #selector(updateView), for: .touchUpInside)
        
        starButton = UIButton(type: .system)
        starButton.setTitle("Star",for:.normal)
        starButton.addTarget(self, action: #selector(toggleStarred), for: .touchUpInside)
        
        view.addSubview(label)
        view.addSubview(button)
        view.addSubview(starButton)
        
        // Layout
        
        label.translatesAutoresizingMaskIntoConstraints = false
        button.translatesAutoresizingMaskIntoConstraints = false
        starButton.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            label.topAnchor.constraint(equalTo: view.topAnchor, constant: 20),
            label.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20),
            
            button.leadingAnchor.constraint(equalTo: label.trailingAnchor, constant: 20),
            button.firstBaselineAnchor.constraint(equalTo: label.firstBaselineAnchor),
            
            starButton.topAnchor.constraint(equalTo: view.topAnchor, constant: 20),
            starButton.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20)
            ])
        
        self.view = view
        
        self.starred = false
        updateView()
    }
    
    @objc func updateView() {
        counter += 1
        label.text = "Counter: \(counter)"
    }
    
    @objc func toggleStarred() {
        self.starred = !self.starred
    }
    
    var starred = false {
        didSet {
            starButton.tintColor = starred ? .orange : .gray
        }
    }
    
}

popo_2017-12-14 20-33-16.jpg