如何让用户从Apple照片库中选择照片?我们如何显示系统相机UI以允许用户拍照?
答案 0 :(得分:8)
编辑:2016年3月15日 - 这是我之前答案的快速版本,如果您正在寻找您将在下面找到的objective-c版本。
- SWIFT -
首先符合UIImagePickerControllerDelegate协议和UINavigationControllerDelegate协议
class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate
启动图像选择器
func actionLaunchCamera()
{
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera)
{
let imagePicker:UIImagePickerController = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerControllerSourceType.Camera
imagePicker.allowsEditing = true
self.presentViewController(imagePicker, animated: true, completion: nil)
}
else
{
let alert:UIAlertController = UIAlertController(title: "Camera Unavailable", message: "Unable to find a camera on this device", preferredStyle: UIAlertControllerStyle.Alert)
self.presentViewController(alert, animated: true, completion: nil)
}
}
实现UIImagePickerDelegate协议的委托方法
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject])
{
// create a filepath with the current date/time as the image name
let savePath:String = self.documentsPath()! + "/" + self.presentDateTimeString() + ".png"
// try to get our edited image if there is one, as well as the original image
let editedImg:UIImage? = info[UIImagePickerControllerEditedImage] as? UIImage
let originalImg:UIImage? = info[UIImagePickerControllerOriginalImage] as? UIImage
// create our image data with the edited img if we have one, else use the original image
let imgData:NSData = editedImg == nil ? UIImagePNGRepresentation(editedImg!)! : UIImagePNGRepresentation(originalImg!)!
// write the image data to file
imgData.writeToFile(savePath, atomically: true)
// dismiss the picker
self.dismissViewControllerAnimated(true, completion: nil)
}
func imagePickerControllerDidCancel(picker: UIImagePickerController)
{
// picker cancelled, dismiss picker view controller
self.dismissViewControllerAnimated(true, completion: nil)
}
// added these methods simply for convenience/completeness
func documentsPath() ->String?
{
// fetch our paths
let paths = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)
if paths.count > 0
{
// return our docs directory path if we have one
let docsDir = paths[0]
return docsDir
}
return nil
}
func presentDateTimeString() ->String
{
// setup date formatter
let dateFormatter:NSDateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "dd-MM-yyyy HH:mm:ss"
// get current date
let now:NSDate = NSDate()
// generate date string from now
let theDateTime = dateFormatter.stringFromDate(now)
return theDateTime
}
- 目标-C -
编辑:更新以在尝试启动相机之前检查相机是否可用。还添加了代码,显示如何将png照片保存到应用程序沙箱中的文档文件夹。
尝试一下(假设使用ARC)。
在.h文件中符合委托协议:
@interface MyViewController : UIViewController <UINavigationControllerDelegate,UIImagePickerControllerDelegate>
在.m文件中启动图像选择器(相机):
-(void)actionLaunchAppCamera
{
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{
UIImagePickerController *imagePicker = [[UIImagePickerController alloc]init];
imagePicker.delegate = self;
imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
imagePicker.allowsEditing = YES;
[self presentModalViewController:imagePicker animated:YES];
}else{
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Camera Unavailable"
message:@"Unable to find a camera on your device."
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil, nil];
[alert show];
alert = nil;
}
}
然后实现委托协议来处理用户取消事件或保存/编辑/等照片。
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
//This creates a filepath with the current date/time as the name to save the image
NSString *presentTimeStamp = [Utilities getPresentDateTime];
NSString *fileSavePath = [Utilities documentsPath:presentTimeStamp];
fileSavePath = [fileSavePath stringByAppendingString:@".png"];
//This checks to see if the image was edited, if it was it saves the edited version as a .png
if ([info objectForKey:UIImagePickerControllerEditedImage]) {
//save the edited image
NSData *imgPngData = UIImagePNGRepresentation([info objectForKey:UIImagePickerControllerEditedImage]);
[imgPngData writeToFile:fileSavePath atomically:YES];
}else{
//save the original image
NSData *imgPngData = UIImagePNGRepresentation([info objectForKey:UIImagePickerControllerOriginalImage]);
[imgPngData writeToFile:fileSavePath atomically:YES];
}
[self dismissModalViewControllerAnimated:YES];
}
-(void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
[self dismissModalViewControllerAnimated:YES];
}
还加入编辑: 以下是用于获取文档路径和当前日期/时间的实用程序类的方法
+(NSString *)documentsPath:(NSString *)fileName {
NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
return [documentsDirectory stringByAppendingPathComponent:fileName];
}
+(NSString *)getPresentDateTime{
NSDateFormatter *dateTimeFormat = [[NSDateFormatter alloc] init];
[dateTimeFormat setDateFormat:@"dd-MM-yyyy HH:mm:ss"];
NSDate *now = [[NSDate alloc] init];
NSString *theDateTime = [dateTimeFormat stringFromDate:now];
dateTimeFormat = nil;
now = nil;
return theDateTime;
}
答案 1 :(得分:5)
您需要使用UIImagePickerController。
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
您必须实现UIImagePickerControllerDelegate
方法imagePickerController:didFinishPickingMediaWithInfo:
,然后使用NSFileManager方法将UIImage存储到您想要的任何文件名。
答案 2 :(得分:1)
这是digitalHound的答案的更新版本,适用于Swift 3.
动作启动相机功能:
func actionLaunchCamera()
{
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.camera)
{
let imagePicker:UIImagePickerController = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = UIImagePickerControllerSourceType.camera
imagePicker.allowsEditing = true
self.present(imagePicker, animated: true, completion: nil)
}
else
{
let alert:UIAlertController = UIAlertController(title: "Camera Unavailable", message: "Unable to find a camera on this device", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Dismiss", style: .default, handler: nil))
alert.view.tintColor = UIColor(red:0.37, green:0.66, blue:0.44, alpha:1.0)
self.present(alert, animated: true, completion: nil)
}
}
代表职能:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
// create a filepath with the current date/time as the image name
let savePath:URL = URL(fileURLWithPath: self.documentsPath()! + "/" + self.presentDateTimeString() + ".png")
// try to get our edited image if there is one, as well as the original image
let editedImg:UIImage? = info[UIImagePickerControllerEditedImage] as? UIImage
let originalImg:UIImage? = info[UIImagePickerControllerOriginalImage] as? UIImage
// create our image data with the edited img if we have one, else use the original image
let imgData:Data = editedImg == nil ? UIImagePNGRepresentation(editedImg!)! : UIImagePNGRepresentation(originalImg!)! as Data
// write the image data to file
try! imgData.write(to: savePath, options: [])
// dismiss the picker
self.dismiss(animated: true, completion: nil)
}
func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
// picker cancelled, dismiss picker view controller
self.dismiss(animated: true, completion: nil)
}
// added these methods simply for convenience/completeness
func documentsPath() ->String?
{
// fetch our paths
let paths = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)
if paths.count > 0
{
// return our docs directory path if we have one
let docsDir = paths[0]
return docsDir
}
return nil
}
func presentDateTimeString() ->String
{
// setup date formatter
let dateFormatter:DateFormatter = DateFormatter()
dateFormatter.dateFormat = "dd-MM-yyyy HH:mm:ss"
// get current date
let now:Date = Date()
// generate date string from now
let theDateTime = dateFormatter.string(from: now)
return theDateTime
}
这对我有用。
答案 3 :(得分:1)
步骤1:确认UIImagePickerControllerDelegate ,UINavigationControllerDelegate
步骤2:(iOS 10+)将此项添加为info.plist文件的密钥
密钥:隐私 - 相机使用说明
值:#Your message
第3步: 这在你的@IBAction
中 if UIImagePickerController.isSourceTypeAvailable(.camera) {
var imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.sourceType = .camera
imagePicker.allowsEditing = false
self.present(imagePicker, animated: true, completion: nil)
}
答案 4 :(得分:0)
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
此代码将触发设备相机..
答案 5 :(得分:0)
//适用于打开图库
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePickerController.delegate = self;
if([[[UIDevice currentDevice] systemVersion] floatValue]>=8.0)
{
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
[self presentViewController:imagePickerController animated:YES completion:nil];
}];
}
else{
[self presentViewController:imagePickerController animated:YES completion:nil];
}
//适用于打开相机
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{
UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.modalPresentationStyle = UIModalPresentationFullScreen;
imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
imagePickerController.delegate = self;
if([[[UIDevice currentDevice] systemVersion] floatValue]>=8.0)
{
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
[self presentViewController:imagePickerController animated:YES completion:nil];
}];
}
else{
[self presentViewController:imagePickerController animated:YES completion:nil];
}
}
答案 6 :(得分:0)
我为需要立即集成此功能的用户创建了此library。您还可以使用一行代码将过滤器应用于图像,只需编写:-
let picker = PickerController()
picker.applyFilter = true // to apply filter after selecting the picture by default false
picker.selectImage(self){ image in
// Use the picture
}