Swift – UIImagePickerController – 如何使用它？
我正在努力去理解它是如何工作的，但是对我来说这很难。 =）我有1个视图，有一个button和一个小的ImageView区域预览。 该button触发imagepickercontroller，和UIView将显示选定的图像。 没有错误，但图像不显示在UIImageView区域。
var imagePicker = UIImagePickerController() @IBOutlet var imagePreview : UIImageView @IBAction func AddImageButton(sender : AnyObject) { imagePicker.modalPresentationStyle = UIModalPresentationStyle.CurrentContext imagePicker.delegate = self self.presentModalViewController(imagePicker, animated: true) } func imagePickerController(picker: UIImagePickerController!, didFinishPickingMediaWithInfo info:NSDictionary!) { var tempImage:UIImage = info[UIImagePickerControllerOriginalImage] as UIImage imagePreview.image = tempImage self.dismissModalViewControllerAnimated(true) } func imagePickerControllerDidCancel(picker: UIImagePickerController!) { self.dismissModalViewControllerAnimated(true) } 您正在抓取一个名为UIImagePickerControllerOriginalImage的UIImage并且不存在这样的图像。 你打算用editingInfo字典中的键UIImagePickerControllerOriginalImage来获取UIImage ：
let tempImage = editingInfo[UIImagePickerControllerOriginalImage] as UIImage
import MobileCoreServices class SecondViewController: UIViewController,UINavigationControllerDelegate, UIImagePickerControllerDelegate { @IBOutlet var img:UIImageView!=nil override func viewDidLoad() { super.viewDidLoad() } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() } @IBAction func buttonTapped(AnyObject) { if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.PhotoLibrary){ println("Button capture") var imag = UIImagePickerController() imag.delegate = self imag.sourceType = UIImagePickerControllerSourceType.PhotoLibrary; //imag.mediaTypes = [kUTTypeImage]; imag.allowsEditing = false self.presentViewController(imag, animated: true, completion: nil) } } func imagePickerController(picker: UIImagePickerController!, didFinishPickingImage image: UIImage!, editingInfo: NSDictionary!) { let selectedImage : UIImage = image //var tempImage:UIImage = editingInfo[UIImagePickerControllerOriginalImage] as UIImage img.image=selectedImage self.dismissViewControllerAnimated(true, completion: nil) } }
细节
xCode 8.3，swift 3.1
码
ImagePicker
import AVFoundation import Photos class ImagePicker: NSObject { var controller = UIImagePickerController() var selectedImage: UIImage? var delegate: ImagePickerDelegate? = nil override init() { super.init() controller.sourceType = .photoLibrary controller.delegate = self } func dismiss() { controller.dismiss(animated: true, completion: nil) } } extension ImagePicker { func cameraAsscessRequest() { if AVCaptureDevice.authorizationStatus(forMediaType: AVMediaTypeVideo) == AVAuthorizationStatus.authorized { delegate?.imagePickerDelegate(canUseCamera: true, delegatedForm: self) } else { AVCaptureDevice.requestAccess(forMediaType: AVMediaTypeVideo) { granted -> Void in self.delegate?.imagePickerDelegate(canUseCamera: granted, delegatedForm: self) } } } func galleryAsscessRequest() { PHPhotoLibrary.requestAuthorization { [weak self] result in if let _self = self { var access = false if result == .authorized { access = true } _self.delegate?.imagePickerDelegate(canUseGallery: access, delegatedForm: _self) } } } } extension ImagePicker: UIImagePickerControllerDelegate, UINavigationControllerDelegate { func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) { let imageName = "img_\(Date().timeIntervalSince1970)" if let image = info[UIImagePickerControllerEditedImage] as? UIImage { delegate?.imagePickerDelegate(didSelect: image, imageName: imageName, delegatedForm: self) } else if let image = info[UIImagePickerControllerOriginalImage] as? UIImage { delegate?.imagePickerDelegate(didSelect: image, imageName: imageName, delegatedForm: self) } else{ print("Something went wrong") } } func imagePickerControllerDidCancel(_ picker: UIImagePickerController) { delegate?.imagePickerDelegate(didCancel: self) } }
ImagePickerDelegate
import UIKit protocol ImagePickerDelegate { func imagePickerDelegate(canUseCamera accessIsAllowed:Bool, delegatedForm: ImagePicker) func imagePickerDelegate(canUseGallery accessIsAllowed:Bool, delegatedForm: ImagePicker) func imagePickerDelegate(didSelect image: UIImage, imageName:String, delegatedForm: ImagePicker) func imagePickerDelegate(didCancel delegatedForm: ImagePicker) } extension ImagePickerDelegate { func imagePickerDelegate(canUseCamera accessIsAllowed:Bool, delegatedForm: ImagePicker) {} func imagePickerDelegate(canUseGallery accessIsAllowed:Bool, delegatedForm: ImagePicker) {} }
用法
的Info.plist
加：
<key>NSPhotoLibraryUsageDescription</key> <string>bla-bla-bla</string> <key>NSCameraUsageDescription</key> <string>bla-bla-bla</string>
视图控制器
import UIKit class ViewController: UIViewController { fileprivate var imagePicker = ImagePicker() @IBOutlet weak var imageView: UIImageView! override func viewDidLoad() { super.viewDidLoad() imagePicker.delegate = self } fileprivate func presentImagePicker(sourceType: UIImagePickerControllerSourceType) { imagePicker.controller.sourceType = sourceType DispatchQueue.main.async { self.present(self.imagePicker.controller, animated: true, completion: nil) } } @IBAction func presentPickerAndRequestPermission(_ sender: UIButton) { presentImagePicker(sourceType: .savedPhotosAlbum) } @IBAction func requestPermissionAndPresentPicker(_ sender: UIButton) { imagePicker.galleryAsscessRequest() } @IBAction func cameraButtonTapped(_ sender: Any) { imagePicker.cameraAsscessRequest() } } extension ViewController: ImagePickerDelegate { func imagePickerDelegate(didSelect image: UIImage, imageName:String, delegatedForm: ImagePicker) { imageView.image = image imagePicker.dismiss() } func imagePickerDelegate(didCancel delegatedForm: ImagePicker) { imagePicker.dismiss() } func imagePickerDelegate(canUseGallery accessIsAllowed: Bool, delegatedForm: ImagePicker) { if accessIsAllowed { presentImagePicker(sourceType: .photoLibrary) } } func imagePickerDelegate(canUseCamera accessIsAllowed: Bool, delegatedForm: ImagePicker) { if accessIsAllowed { // works only on real device (crash on simulator) presentImagePicker(sourceType: .camera) } } }
Main.storyboard
<?xml version="1.0" encoding="UTF-8"?> <document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="12118" systemVersion="16E195" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES" initialViewController="8h3-th-UId"> <device id="retina4_7" orientation="portrait"> <adaptation id="fullscreen"/> </device> <dependencies> <deployment identifier="iOS"/> <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12086"/> <capability name="Constraints to layout margins" minToolsVersion="6.0"/> <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/> </dependencies> <scenes> <!--View Controller--> <scene sceneID="tne-QT-ifu"> <objects> <viewController id="BYZ-38-t0r" customClass="ViewController" customModule="stackoverflow_43425753" customModuleProvider="target" sceneMemberID="viewController"> <layoutGuides> <viewControllerLayoutGuide type="top" id="y3c-jy-aDJ"/> <viewControllerLayoutGuide type="bottom" id="wfy-db-euE"/> </layoutGuides> <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC"> <rect key="frame" x="0.0" y="0.0" width="375" height="667"/> <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/> <subviews> <imageView clipsSubviews="YES" userInteractionEnabled="NO" contentMode="scaleAspectFill" horizontalHuggingPriority="251" verticalHuggingPriority="251" translatesAutoresizingMaskIntoConstraints="NO" id="lOV-da-uaY"> <rect key="frame" x="67" y="269" width="240" height="128"/> <color key="backgroundColor" white="0.66666666666666663" alpha="1" colorSpace="calibratedWhite"/> <constraints> <constraint firstAttribute="height" constant="128" id="iv7-J9-AJp"/> <constraint firstAttribute="width" constant="240" id="pOJ-T3-hG6"/> </constraints> </imageView> <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="f1v-ZZ-Ymw"> <rect key="frame" x="16" y="231" width="343" height="30"/> <state key="normal" title="Request permission before present picker"/> <connections> <action selector="requestPermissionAndPresentPicker:" destination="BYZ-38-t0r" eventType="touchUpInside" id="lyc-yI-9TS"/> </connections> </button> <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="41F-AZ-10t"> <rect key="frame" x="16" y="193" width="343" height="30"/> <state key="normal" title="Present picker before request permission"/> <connections> <action selector="presentPickerAndRequestPermission:" destination="BYZ-38-t0r" eventType="touchUpInside" id="Wfy-u3-9Xi"/> </connections> </button> </subviews> <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/> <constraints> <constraint firstItem="f1v-ZZ-Ymw" firstAttribute="top" secondItem="41F-AZ-10t" secondAttribute="bottom" constant="8" symbolic="YES" id="H79-n9-dbA"/> <constraint firstItem="lOV-da-uaY" firstAttribute="top" secondItem="f1v-ZZ-Ymw" secondAttribute="bottom" constant="8" symbolic="YES" id="QEf-Il-7CA"/> <constraint firstItem="41F-AZ-10t" firstAttribute="leading" secondItem="f1v-ZZ-Ymw" secondAttribute="leading" id="T9O-9X-o17"/> <constraint firstItem="f1v-ZZ-Ymw" firstAttribute="centerX" secondItem="lOV-da-uaY" secondAttribute="centerX" id="YEX-d4-Ktl"/> <constraint firstItem="41F-AZ-10t" firstAttribute="trailing" secondItem="f1v-ZZ-Ymw" secondAttribute="trailing" id="b0d-Z3-EPR"/> <constraint firstItem="lOV-da-uaY" firstAttribute="centerX" secondItem="8bC-Xf-vdC" secondAttribute="centerX" id="fjW-qF-w9E"/> <constraint firstItem="lOV-da-uaY" firstAttribute="centerY" secondItem="8bC-Xf-vdC" secondAttribute="centerY" id="paK-zP-Zny"/> <constraint firstItem="41F-AZ-10t" firstAttribute="leading" secondItem="8bC-Xf-vdC" secondAttribute="leadingMargin" id="wOA-e7-6ND"/> </constraints> </view> <navigationItem key="navigationItem" id="O38-0b-A9f"> <barButtonItem key="leftBarButtonItem" systemItem="camera" id="T6B-k6-KJ9"> <connections> <action selector="cameraButtonTapped:" destination="BYZ-38-t0r" id="OBY-pO-8HL"/> </connections> </barButtonItem> </navigationItem> <connections> <outlet property="imageView" destination="lOV-da-uaY" id="EYi-qU-noP"/> </connections> </viewController> <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/> </objects> <point key="canvasLocation" x="1013.6" y="-579.76011994002999"/> </scene> <!--Navigation Controller--> <scene sceneID="BZr-BH-sMY"> <objects> <navigationController automaticallyAdjustsScrollViewInsets="NO" id="8h3-th-UId" sceneMemberID="viewController"> <toolbarItems/> <navigationBar key="navigationBar" contentMode="scaleToFill" id="J5d-TE-5r7"> <rect key="frame" x="0.0" y="0.0" width="375" height="44"/> <autoresizingMask key="autoresizingMask"/> </navigationBar> <nil name="viewControllers"/> <connections> <segue destination="BYZ-38-t0r" kind="relationship" relationship="rootViewController" id="UWM-bm-ZNP"/> </connections> </navigationController> <placeholder placeholderIdentifier="IBFirstResponder" id="Hzd-Nh-WhC" userLabel="First Responder" sceneMemberID="firstResponder"/> </objects> <point key="canvasLocation" x="125.59999999999999" y="-578.86056971514245"/> </scene> </scenes> </document>
结果
尝试这个：
func imagePickerController(picker: UIImagePickerController!, didFinishPickingMediaWithInfo info:NSDictionary!) { let tempImage = info[UIImagePickerControllerOriginalImage] as! UIImage imagePreview.image = tempImage
或者你也可以使用? 代替! 。