DAY 30『 从相簿选取照片（ 有裁剪照片功能 ） 』ImagePicker - Part2

在 @IBAction 里

1. 令 vc 为 UIImagePickerController
   let vc = UIImagePickerController()
2. 新增相簿权限
   vc.sourceType = .photoLibrary // 相簿
3. 设定委任
   vc.delegate = self
4. 允许用户编辑选定的图像或影像
   vc.allowsEditing = true
5. 设定跳页
   present(vc, animated: true)

到这边会报错是正常的，因为没给它 UIImagePickerControllerDelegate
因此在专案里用 extension 去写委任

extension MainVC: UIImagePickerControllerDelegate, UINavigationControllerDelegate{
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let image = info[UIImagePickerController.InfoKey(rawValue: "UIImagePickerControllerEditedImage") ] as? UIImage{
            imageView.image = image
        }
        picker.dismiss(animated: true, completion: nil)
    }
    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        picker.dismiss(animated: true, completion: nil)
    }
}

附上完整程序码

import UIKit

class MainVC: UIViewController {

    @IBOutlet weak var imageView: UIImageView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.navigationController?.setNavigationBarHidden(true, animated: false)
    }
    @IBAction func didTapButton(_:UIButton) {
        let vc = UIImagePickerController()
        vc.sourceType = .photoLibrary
        vc.delegate = self
        vc.allowsEditing = true
        present(vc, animated: true)
    }
}

extension MainVC: UIImagePickerControllerDelegate, UINavigationControllerDelegate{
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let image = info[UIImagePickerController.InfoKey(rawValue: "UIImagePickerControllerEditedImage") ] as? UIImage{
            imageView.image = image
        }
        picker.dismiss(animated: true, completion: nil)
    }
    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        picker.dismiss(animated: true, completion: nil)
    }
}

这样就完成从相簿选取照片的实作了！

#完赛心得

13th铁人赛到今天完赛了，终於完成连续30天的自我挑战！透过铁人赛，让自己从最基本的说明介绍开始，更扎实地打好基本功，也更了解那些官方文件未提及的面向。这30天记录了使用 swift 开发实作的过程，希望自己在完赛後，也能持续使用 swift 开发更多实作。感谢各位邦友收看!