Swift ImagePickerController didFinishPickingMediaWithInfo 未触发
Swift ImagePickerController didFinishPickingMediaWithInfo not fired
我使用 ImagePickerController
来获取个人资料图片。用户有一个按钮。该按钮触发 CamRoll 功能。单击该按钮时,会出现正常的 ImagePickerViewController
,但不会调用 didFinishPickingMediaWithInfo
。在 Swift/Xcode 的早期版本中,调用了相同的代码。这是我的代码。
import UIKit
class AnnonseViewController: UIViewController, UIImagePickerControllerDelegate {
@IBOutlet var Image: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func CamRoll(_ sender: Any) {
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerControllerSourceType.photoLibrary
self.present(imagePicker, animated: true, completion: nil)
}
private func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [AnyHashable: Any]) {
var image = info[UIImagePickerControllerOriginalImage] as! UIImage
let imageSize = image.size
let width = imageSize.width
let height = imageSize.height
if width != height {
let newDimensions = min(width,height)
let widthOffset = (width - newDimensions) / 2
let heightOffset = (height - newDimensions) / 2
UIGraphicsBeginImageContextWithOptions(CGSize(width: newDimensions, height: newDimensions), false, 0.0)
image.draw(at: CGPoint(x: -widthOffset, y: -heightOffset), blendMode: .copy, alpha: 1.0)
image = UIGraphicsGetImageFromCurrentImageContext()! as UIImage
UIGraphicsEndImageContext()
}
UIGraphicsBeginImageContext(CGSize(width: 150, height: 150))
_ = UIGraphicsGetCurrentContext()
image.draw(in: CGRect(x: 0, y: 0, width: 150, height: 150))
let smallImage = UIGraphicsGetImageFromCurrentImageContext()
Image.image = smallImage
picker.dismiss(animated: true, completion: nil)
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
picker.dismiss(animated: true, completion: nil)
}
}
为什么没有调用代码?
UIImagePickerControllerDelegate
in Swift 3 for imagePickerController(_:didFinishPickingMediaWithInfo:)
的正确委托方法如下。
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
}
您可以在 UIImagePickerControllerDelegate
上查看 Apple Documentations 了解更多详情。
在 Swift 4 中,该方法再次具有不同的签名,将 String 替换为 UIImagePickerController.InfoKey:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]){
}
我使用 ImagePickerController
来获取个人资料图片。用户有一个按钮。该按钮触发 CamRoll 功能。单击该按钮时,会出现正常的 ImagePickerViewController
,但不会调用 didFinishPickingMediaWithInfo
。在 Swift/Xcode 的早期版本中,调用了相同的代码。这是我的代码。
import UIKit
class AnnonseViewController: UIViewController, UIImagePickerControllerDelegate {
@IBOutlet var Image: UIImageView!
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func CamRoll(_ sender: Any) {
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerControllerSourceType.photoLibrary
self.present(imagePicker, animated: true, completion: nil)
}
private func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [AnyHashable: Any]) {
var image = info[UIImagePickerControllerOriginalImage] as! UIImage
let imageSize = image.size
let width = imageSize.width
let height = imageSize.height
if width != height {
let newDimensions = min(width,height)
let widthOffset = (width - newDimensions) / 2
let heightOffset = (height - newDimensions) / 2
UIGraphicsBeginImageContextWithOptions(CGSize(width: newDimensions, height: newDimensions), false, 0.0)
image.draw(at: CGPoint(x: -widthOffset, y: -heightOffset), blendMode: .copy, alpha: 1.0)
image = UIGraphicsGetImageFromCurrentImageContext()! as UIImage
UIGraphicsEndImageContext()
}
UIGraphicsBeginImageContext(CGSize(width: 150, height: 150))
_ = UIGraphicsGetCurrentContext()
image.draw(in: CGRect(x: 0, y: 0, width: 150, height: 150))
let smallImage = UIGraphicsGetImageFromCurrentImageContext()
Image.image = smallImage
picker.dismiss(animated: true, completion: nil)
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
picker.dismiss(animated: true, completion: nil)
}
}
为什么没有调用代码?
UIImagePickerControllerDelegate
in Swift 3 for imagePickerController(_:didFinishPickingMediaWithInfo:)
的正确委托方法如下。
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
}
您可以在 UIImagePickerControllerDelegate
上查看 Apple Documentations 了解更多详情。
在 Swift 4 中,该方法再次具有不同的签名,将 String 替换为 UIImagePickerController.InfoKey:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]){
}