如何在 Swift 中从相机或照片库加载图像 [关闭]

Posted 2023-02-23

【中文标题】如何在 Swift 中从相机或照片库加载图像 [关闭]

【英文标题】：How to load image from camera or photo library in Swift [closed]

【发布时间】：2016-10-01 23:20:17

【问题描述】：

例如，您如何使用相机拍照或从照片库中选择图像以便能够将其显示在 imageView 中？

对此的任何帮助将不胜感激。

【问题讨论】：

我已经为你发布了一个答案，但是你得到了所有的反对，因为这不是“为你编码”的网站。您必须提供代码，我们正在帮助您查找错误并改进您的代码。所以下一次，如果你遇到困难，请尝试谷歌解决方案并获得帮助。现在：我已经为您发布了一个功能齐全的选项。玩得开心

我知道这不是人们为我工作的地方，我只是想知道我可以从哪里开始。我不希望任何人为我写出来，尽管我很欣赏你发布的答案。

我不想冒犯你或任何朋友。只是想告诉你，为什么你的票数都被否决了。你得到了我的支持，所以它不会变得太糟糕，如果我的工作对你有帮助，我很高兴回答你的问题，以便你检查它。如果您需要进一步的帮助，请告诉我。

【参考方案1】：

Swift 5+ 的完整更新，包括 Github Repo

首先，我们要将所有内容组织到一个专门的类中。

import MobileCoreServices
import UIKit

class CameraProvider: NSObject 

    enum PhotoLibraryTypes 
        case photoLibrary, savedPhotosAlbum
        var casted: UIImagePickerController.SourceType 
            switch self 
            case .photoLibrary: return UIImagePickerController.SourceType.photoLibrary
            case .savedPhotosAlbum: return UIImagePickerController.SourceType.savedPhotosAlbum
            
        
    

    public typealias SourceType = UIImagePickerController.SourceType
    public typealias ImagePicker = UIImagePickerController
    public typealias Delegate = UINavigationControllerDelegate & UIImagePickerControllerDelegate

    private let delegate: Delegate

    init(delegate: Delegate) 
        self.delegate = delegate
    

    // MARK: - Public

    public func getImagePicker(source: PhotoLibraryTypes,
                               canEditPhotos: Bool = true,
                               onlyImages: Bool = false) throws -> ImagePicker 

        do 
            return try getBaseController(
                source: source.casted,
                allowsEditing: canEditPhotos,
                onlyImages: onlyImages
            )
         catch 
            throw error
        
    

    public func getCamera(canEditPhotos: Bool = true,
                          onlyImages: Bool = false) throws -> ImagePicker 

        do 
            let picker = try getBaseController(
                source: .camera,
                allowsEditing: canEditPhotos,
                onlyImages: onlyImages
            )

            if UIImagePickerController.isCameraDeviceAvailable(.rear) 
                picker.cameraDevice = .rear
             else if UIImagePickerController.isCameraDeviceAvailable(.front) 
                picker.cameraDevice = .front
             else 
                throw "No known camera type available"
            

            picker.showsCameraControls = true
            return picker
         catch 
            throw error
        
    

    // MARK: - Private

    private func getBaseController(source: SourceType,
                                   allowsEditing: Bool,
                                   onlyImages: Bool) throws -> ImagePicker 

        guard UIImagePickerController.isSourceTypeAvailable(source) else 
            throw "Requested source not available"
        

        let picker = UIImagePickerController()
        let imageType = kUTTypeImage as String
        picker.sourceType = source
        picker.allowsEditing = allowsEditing
        picker.delegate = self.delegate

        if onlyImages,
           let mediaTypes = UIImagePickerController.availableMediaTypes(for: source),
           mediaTypes.contains(imageType)
            picker.mediaTypes = [imageType]
        

        return picker
    


extension String: LocalizedError 
    public var errorDescription: String?  return self 

最后我们调用我们的CameraProvider如下。

import UIKit

class ViewController: UIViewController 
    override func viewDidAppear(_ animated: Bool) 
        super.viewDidAppear(animated)
        let provider = CameraProvider(delegate: self)

        do 
            let picker = try provider.getImagePicker(source: .photoLibrary)
            present(picker, animated: true)
         catch 
            NSLog("Error: \(error.localizedDescription)")
        
    


extension ViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate 

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) 
        let image = (
            info[UIImagePickerController.InfoKey.editedImage] as? UIImage ??
            info[UIImagePickerController.InfoKey.originalImage] as? UIImage
        )
        picker.dismiss(animated: true, completion: nil)
    

【讨论】：

很好的回答大卫谢谢分享

好吧，不客气

您的代码运行良好，但使用 canEdit 从库加载时除外：当我选择图像时它会崩溃

非常有用的答案。谢谢你。但我猜有一个小错误。您在 getPhotoLibraryOn 中检查了两次 isPhotoLibraryAvailable。第二个应该是 isSavedPhotoAlbumAvailable。

太棒了！完美运行。谢谢你