swift是对OC语法的简化，使用函数式编码方式，编码更简洁灵活。使用let来声明常量，var来声明变量。一些类方法的调用可以直接使用点来获取类方法，省去类名，编译器会自动识别对应的类。下面是对一些控件的初始化及展示的写法。
import UIKit import WebKit import MapKit class ViewController: UIViewController,UITableViewDelegate,UITableViewDataSource,UICollectionViewDelegate,UICollectionViewDataSource,UIPickerViewDelegate,UIPickerViewDataSource { override func viewDidLoad() { super.viewDidLoad() //1、UIButton let button = UIButton.init(type: UIButton.ButtonType.custom) button.frame = CGRect(x: 100, y: 60, width: 100, height: 40) button.backgroundColor = .red button.setTitle("按钮", for: .normal) button.titleLabel?.textColor = .white button.addTarget(self, action: #selector(btn(button:)), for: .touchUpInside) self.view.addSubview(button) self.setTitle(view: button) //2、UILabel let label = UILabel.init(frame: CGRect(x: 100, y: 110, width: 100, height: 40)); label.text = "这是个label" label.backgroundColor = .gray label.textColor = .white label.textAlignment = .center self.view.addSubview(label) self.setTitle(view: label) //3、UIView let view = UIView.init(frame: CGRect(x: 100, y: 160, width: 100, height: 50)) view.backgroundColor = .yellow view.layer.cornerRadius = 5.0 view.isUserInteractionEnabled = true let tap = UITapGestureRecognizer.init(target: self, action: #selector(tap(tap:))) view.addGestureRecognizer(tap) self.view.addSubview(view) self.setTitle(view: view) //4、UIImageView let imageview = UIImageView.init(frame: CGRect(x: 100, y: 220, width: 100, height: 100)) imageview.image = UIImage.init(named: "hibo.jpg") self.view.addSubview(imageview) self.setTitle(view: imageview) //5、UITextField let textfield = UITextField.init(frame: CGRect(x: 100, y: 330, width: 100, height: 40)) textfield.borderStyle = .roundedRect textfield.placeholder = "请输入内容" textfield.clearButtonMode = .whileEditing self.view.addSubview(textfield) self.setTitle(view: textfield) //6、UITextView let textview = UITextView.init(frame: CGRect(x: 100, y: 380, width: 100, height: 50)) textview.backgroundColor = .init(red: 0.8, green: 0.8, blue: 0.8, alpha: 1) textview.text = "我再textview中显示" self.view.addSubview(textview) self.setTitle(view: textview) //7、UIAlertController let alertBtn = UIButton.init(type: UIButton.ButtonType.custom) alertBtn.frame = CGRect(x: 100, y: 440, width: 100, height: 40) alertBtn.backgroundColor = UIColor.red alertBtn.setTitle("弹框", for: .normal) alertBtn.titleLabel?.textColor = .white alertBtn.addTarget(self, action: #selector(alert), for: .touchUpInside) self.view.addSubview(alertBtn) self.setTitle(view: alertBtn) //8、UISwitch let swc = UISwitch.init(frame: CGRect(x: 100, y: 490, width: 100, height: 40)) swc.isOn = true self.view.addSubview(swc) self.setTitle(view: swc) //9、UIProgressView let progress = UIProgressView.init(frame: CGRect(x: 100, y: 560, width: 100, height: 40)) progress.progress = 0.5 self.view.addSubview(progress) self.setTitle(view: progress) //10、UISlider let slider = UISlider.init(frame: CGRect(x: 100, y: 600, width: 100, height: 40)) slider.value = 0.6 self.view.addSubview(slider) self.setTitle(view: slider) //11、UIPickerView let datePic = UIPickerView.init(frame: CGRect(x: 100, y: 660, width: 100, height: 120)) datePic.delegate = self datePic.dataSource = self self.view.addSubview(datePic) self.setTitle(view: datePic) //12、MKMapView let map = MKMapView.init(frame: CGRect(x: 300, y: button.frame.origin.y, width: 100, height: 100)) map.showsUserLocation = true map.mapType = .satellite self.view.addSubview(map) self.setTitle(view:map) //13、UITableView let tableview = UITableView.init(frame: CGRect(x: 300, y: map.frame.origin.y+map.frame.size.height+10, width: 100, height: 100), style: .plain) tableview.delegate = self tableview.dataSource = self tableview.register(UITableViewCell.self, forCellReuseIdentifier: "cell") self.view.addSubview(tableview) self.setTitle(view:tableview) //14、UICollectionView let layout = UICollectionViewFlowLayout.init() layout.itemSize = CGSize(width: 30, height: 30) layout.minimumLineSpacing = 5//设置最小行间距 layout.minimumInteritemSpacing = 0//设置最小列间距 let collection = UICollectionView.init(frame: CGRect(x: 300, y: tableview.frame.origin.y+tableview.frame.size.height+10, width: 100, height: 100), collectionViewLayout: layout) collection.delegate = self collection.dataSource = self collection.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "collection") self.view.addSubview(collection) self.setTitle(view:collection) //15、WKWebView let webview = WKWebView.init(frame: CGRect(x: 300, y: collection.frame.origin.y+collection.frame.size.height+10, width: 100, height: 240), configuration: WKWebViewConfiguration.init()) webview.backgroundColor = .gray webview.load(URLRequest.init(url: URL.init(string: "https://www.baidu.com")!)) self.view.addSubview(webview) self.setTitle(view: webview) } //设置标题 @objc func setTitle(view:UIView){ let label = UILabel.init(frame: CGRect(x: view.frame.origin.x-90, y: view.frame.origin.y, width: 90, height: 30)) label.font = .systemFont(ofSize: 12) label.numberOfLines = 0 label.text = NSStringFromClass(view.classForCoder)+"：" self.view.addSubview(label) } //点击时间带参数方法 @objc func btn(button:UIButton){ print(button); print("点击了按钮") } //手势事件 @objc func tap(tap:UITapGestureRecognizer){ print(tap) } //弹框 @objc func alert(){ //UIAlertController let alert = UIAlertController.init(title: "提示", message: "message", preferredStyle: .alert) alert .addAction(UIAlertAction.init(title: "取消", style: .cancel, handler: { (UIAlertAction) in print("取消") })) alert.addAction(UIAlertAction.init(title: "确定", style: .default, handler: { (UIAlertAction) in print("确定") })) self.present(alert, animated: true) {print("弹出")} } //UIPickerView func numberOfComponents(in pickerView: UIPickerView) -> Int { return 2; } func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int { return 10 } func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? { return "hibo" } func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView { let label = UILabel.init(frame: CGRect(x: 0, y: 0, width: 50, height: 30)) label.text = "hibo" return label } //tableview func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { return 100 } func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { let cell = tableView.dequeueReusableCell(withIdentifier: "cell") cell?.textLabel?.text = "row:"+indexPath.row.description return cell! } //collectionview func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return 10 } func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collection", for: indexPath) cell.backgroundColor = .red return cell } }运行结果：
通过上面的练习，就已经熟悉了Swift语法了，可以搭建项目了。
