如何让用户从相机胶卷或照片库中挑选照片？

Question

我正在制作一个小照片编辑应用程序以获得乐趣.用户必须从相机胶卷中选择一张照片,然后将其导入进行修改.

这通常如何工作？我见过许多应用程序允许使用标准控制器看起来总是一样的.

是否也可以直接访问该库或自定义该控制器的外观？

我应该从哪里开始寻找？

Answer 1

最简单的方法是在简单的alertView中使用UIImagePickerController.

例如,您希望有人点按他们的个人资料照片,并能够从他们的相机或照片库中设置新图像.

@IBAction func btnProfilePicTap(sender: AnyObject) {
    let picker = UIImagePickerController()
    picker.delegate = self
    let alert = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
    alert.addAction(UIAlertAction(title: "Camera", style: .Default, handler: {
        action in
        picker.sourceType = .Camera
        self.presentViewController(picker, animated: true, completion: nil)
    }))
    alert.addAction(UIAlertAction(title: "Photo Library", style: .Default, handler: {
        action in
        picker.sourceType = .PhotoLibrary
        self.presentViewController(picker, animated: true, completion: nil)
    }))
    alert.addAction(UIAlertAction(title: "Cancel", style: .Cancel, handler: nil))
    self.presentViewController(alert, animated: true, completion: nil)
}

然后只需添加代理即可完成.

extension ProfileViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate {

    func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
        //use image here!
        dismissViewControllerAnimated(true, completion: nil)
    }

    func imagePickerControllerDidCancel(picker: UIImagePickerController) {
        dismissViewControllerAnimated(true, completion: nil)
    }

}

对不起,这个例子很快,但我希望它仍然有帮助.

Answer 2

我致力于一个允许用户选择个人形象的应用程序.我有两个UIButtons可以帮助用户选择一张图片,无论是来自相机还是图书馆.它是这样的:

- (void)camera {
if(![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]){
    return;
}
UIImagePickerController *picker = [[[UIImagePickerController alloc] init] autorelease];
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
//Permetto la modifica delle foto
picker.allowsEditing = YES;
//Imposto il delegato
[picker setDelegate:self];

[self presentModalViewController:picker animated:YES];
}
- (void)library {
//Inizializzo la classe per la gestione della libreria immagine
UIImagePickerController *picker = [[[UIImagePickerController alloc] init] autorelease];
picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
//Permetto la modifica delle foto
picker.allowsEditing = YES;
//Imposto il delegato
[picker setDelegate:self];

[self presentModalViewController:picker animated:YES];
}

你必须实现UIImagePickerControllerDelegate:

@interface PickPictureViewController : UIViewController <UIImagePickerControllerDelegate>

@implementation PickPictureViewController

#pragma mark UIImagePickerController Delegate
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
UIImage *pickedImage = [info objectForKey:UIImagePickerControllerEditedImage];
if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
    UIImageWriteToSavedPhotosAlbum(pickedImage, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
}
[self dismissModalViewControllerAnimated:YES];
}
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker{
[self dismissModalViewControllerAnimated:YES];
}
- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{}

希望能帮助到你!;)

Answer 3

这个答案仅适用于物理设备!

访问摄像头:

- (void)takePhoto {

UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;

[self presentViewController:picker animated:YES completion:NULL];

}

访问相机胶卷:

- (void)selectPhoto {

UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

[self presentViewController:picker animated:YES completion:NULL];


}

实现UIImagePickerController的委托方法:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

UIImage *chosenImage = info[UIImagePickerControllerEditedImage];
self.imageView.image = chosenImage;

[picker dismissViewControllerAnimated:YES completion:NULL];

}

还有这个:

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {

[picker dismissViewControllerAnimated:YES completion:NULL];

}

另请查看此链接的更多信息

Answer 4

SWIFT 2.0

感谢William T.这对我的UITapGestureRecognizer有用

func selectPhoto(tap: UITapGestureRecognizer) {
    let picker = UIImagePickerController()
    picker.delegate = self
    let alert = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
    alert.addAction(UIAlertAction(title: "Camera", style: .Default, handler: {
        action in
        picker.sourceType = .Camera
        picker.allowsEditing = true
        self.presentViewController(picker, animated: true, completion: nil)
    }))
    alert.addAction(UIAlertAction(title: "Photo Library", style: .Default, handler: {
        action in
        picker.sourceType = .PhotoLibrary
        picker.allowsEditing = true
        self.presentViewController(picker, animated: true, completion: nil)
    }))
    alert.addAction(UIAlertAction(title: "Cancel", style: .Cancel, handler: nil))
    self.presentViewController(alert, animated: true, completion: nil)
}

我添加了以下内容,让我在选择.Camera和.PhotoLibrary之后编辑照片:

picker.allowsEditing = true