拍摄照片或从照片库中选择照片后，UIImageView 未使用新图像更新答案

【问题标题】：UIImageView not updating with new image after picture taken or picture chosen from photo library拍摄照片或从照片库中选择照片后，UIImageView 未使用新图像更新
【发布时间】：2017-04-11 03:21:24
【问题描述】：

在我拍照或从我的照片库中选择一张图片后，我试图在 UIImageView 中填充图像。

这是处理相机和照片库激活的代码：

@IBAction func activateCmera(_ sender: Any) {
    if (UIImagePickerController.isSourceTypeAvailable(.camera)) {
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .camera
        imagePicker.allowsEditing = false
        self.present(imagePicker, animated: true, completion: nil)
    }
}


@IBAction func activatePhotoLib(_ sender: Any) {
    if (UIImagePickerController.isSourceTypeAvailable(.photoLibrary)) {
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .photoLibrary
        imagePicker.allowsEditing = false
        self.present(imagePicker, animated: true, completion: nil)
    }
}

这是在 UIImageView 中填充图像的代码：

@IBOutlet weak var imageView: UIImageView!

func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
    let image = info[UIImagePickerControllerOriginalImage] as! UIImage
    self.imageView.contentMode = .scaleAspectFit
    self.imageView.image = image
    self.dismiss(animated: true, completion: nil);
}

目前，在我用相机拍照或从照片库中选择图像后，我被重定向到应用程序的初始视图，而 UIImageView 空间没有随照片更新。

感谢任何帮助！

【问题讨论】：

标签： ios swift image uiimageview

【解决方案1】：

我遇到了同样的问题。显然 imagePickerController 函数自上次回答以来又发生了变化。我不得不稍微改变一下函数以使用 Swift 5.4：

/ Doesn't work
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// Does work
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {

info 参数现在需要一个 UIImagePickerController InfoKeys 字典。

【讨论】：

【解决方案2】：

**你需要像全局对象一样保存 UIImagePickerController，之后，你需要把这段代码推送到你的动作函数上 **

@objc func getImage() {

    imagePicker.sourceType = UIImagePickerControllerSourceType.photoLibrary

    imagePicker.allowsEditing = false

    imagePicker.modalPresentationStyle = .overCurrentContext

    present(imagePicker, animated: true)

}

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

    if let image = info[UIImagePickerControllerOriginalImage] as? UIImage {
    imageView.image = image
 }

self.dismiss(animated: true, completion: nil);

}

【讨论】：

【解决方案3】：

这似乎是与 XCode 未能解释 imagePickerController 函数语法已更改（自 Swift 3 起）有关的问题。你会在网上找到这两种编写函数的方法。您还可以在 XCode 中同时使用这两者而不会出现任何错误。但只有第二个才能真正正确地获取图像。

(Option 1 - doesn't work, but XCode doesn't flag it):
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) { }

(Option 2 - this is the right syntax!):
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) { }

【讨论】：

【解决方案4】：

在Swift 3 中，您需要通过在keys 下方添加plist 来获得访问photoLibrary 的权限，并且您需要使用正确的delegate 方法。

将UIImagePickerControllerDelegate& UINavigationControllerDelegate 添加到您的class 并将imagePicker delegate 设置为viewDidLoad 并尝试以下代码。

    let imagePicker = UIImagePickerController()

    @IBAction func activatePhotoLib(_ sender: UIButton) { 
    if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.photoLibrary) {
        imagePicker.delegate = self
        imagePicker.sourceType = UIImagePickerControllerSourceType.photoLibrary;
        imagePicker.allowsEditing = false
        self.present(imagePicker, animated: true, completion: nil)
       } 
     }

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    if let image = info[UIImagePickerControllerOriginalImage] as? UIImage {
        imageView.image = image
     }
    picker.dismiss(animated: true, completion: nil);
    }

输出：updated

【讨论】：