我正在尝试一个简单的相机应用程序来练习。遵循以下示例:iOS 6 App 和 iOS 4 App

我的代码是这样的:

ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UINavigationControllerDelegate, UIImagePickerControllerDelegate>
{
    UIButton *button;
    UIImageView *imageView;
}
@property (nonatomic, retain) IBOutlet UIImageView *imageView;
- (IBAction)useCamera;
- (IBAction)useCameraRoll;
@end

ViewController.m

#import "ViewController.h"
#import <MobileCoreServices/MobileCoreServices.h>

@interface ViewController ()

@end

@implementation ViewController

@synthesize imageView;


- (void) alertView:(UIAlertView *)alert clickedButtonAtIndex:(NSInteger)buttonIndex
{
    // After saving iamge, dismiss camera
    [self dismissViewControllerAnimated:YES completion:NULL];
}

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    UIAlertView *alert;

    // Unable to save the image
    if (error)
        alert = [[UIAlertView alloc] initWithTitle:@"Error"
                                           message:@"Unable to save image to Photo Album."
                                          delegate:self cancelButtonTitle:@"Ok"
                                 otherButtonTitles:nil];
    else // All is well
        alert = [[UIAlertView alloc] initWithTitle:@"Success"
                                           message:@"Image saved to Photo Album."
                                          delegate:self cancelButtonTitle:@"Ok"
                                 otherButtonTitles:nil];


    [alert show];
}

- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    // Access the uncropped image from info dictionary
    UIImage *image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];

    // Save image
    UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

}

- (id)init
{
    if (self = [super init])
    {
        self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
        self.view.backgroundColor = [UIColor grayColor];

        // Button to activate camera
        button = [[UIButton alloc] initWithFrame:CGRectMake(80, 55, 162, 53)];
        [button setBackgroundImage:[UIImage imageNamed:@"Camera.png"] forState:UIControlStateNormal];
        [button addTarget:self action:@selector(buttonPressed:) forControlEvents: UIControlEventTouchUpInside];
        [self.view addSubview:button];
    }

    return self;  
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
- (IBAction)useCamera
{
    if ([UIImagePickerController isSourceTypeAvailable:
         UIImagePickerControllerSourceTypeCamera])
    {
        UIImagePickerController *imagePicker =
        [[UIImagePickerController alloc] init];
        imagePicker.delegate = self;
        imagePicker.sourceType =
        UIImagePickerControllerSourceTypeCamera;
        imagePicker.mediaTypes = [NSArray arrayWithObjects:
                                  (NSString *) kUTTypeImage,
                                  nil];
        imagePicker.allowsEditing = NO;
        [self presentViewController:imagePicker animated:YES completion:nil];

    }
}

- (IBAction)useCameraRoll
{
    if ([UIImagePickerController isSourceTypeAvailable:
         UIImagePickerControllerSourceTypeSavedPhotosAlbum])
    {
        UIImagePickerController *imagePicker =
        [[UIImagePickerController alloc] init];
        imagePicker.delegate = self;
        imagePicker.sourceType =
        UIImagePickerControllerSourceTypePhotoLibrary;
        imagePicker.mediaTypes = [NSArray arrayWithObjects:
                                  (NSString *) kUTTypeImage,
                                  nil];
        imagePicker.allowsEditing = NO;
        [self presentViewController:imagePicker animated:YES completion:nil];
    }
}

@end

我的问题 我喜欢从应用程序本身访问相机。发生的事情是，当我单击 useCamera 按钮时，它会打开相机并拍摄图像。它有可能从应用程序本身做到这一点吗？对不起，如果这是一个愚蠢的问题。如果我做错了什么，请指出我。

最佳答案

是的，使用 UIImagePickerController class .

单击相机按钮时，显示 UIImagePickerController 的实例。此外，由于某些 iOS 设备(例如原始 iPad 或某些较旧的 iPod touch)没有相机，因此我不建议使用单独的按钮/方法来拍摄新照片而不是使用已保存照片中的照片。使用一个按钮并使用类中的可用方法根据设备的功能设置其源类型。这可能需要重新考虑您的应用程序的设计，但它也更有可能通过 Apple 的 UI 检查，因为他们可能不会批准具有专门用于拍照但可以在没有相机的设备上运行的按钮的应用程序。

一旦用户拍摄了新照片或从相机胶卷中选择了照片，使用 UIImagePickerControllerDelegate class 中的 imagePickerController:didFinishPickingMediaWithInfo: 方法将用户的选择传递给您的代码。

UIImagePickerController 的实例设计为在使用相机时在所有 iOS 设备上以模态方式呈现。请记住，顾名思义，它们是 Controller 而不是 View ，因此它们不应用作 UIView 的 subview 。虽然您可以在展示方式上发挥创意，但几乎肯定会产生一些副作用，并且会进一步增加 Apple 拒绝它的可能性。它只是看起来像它正在退出应用程序来拍照，但因为你是从你的应用程序中展示 Controller ，它仍然是它的一部分。 Apple 不允许直接访问相机硬件，这正是他们创建此类的原因。

关于iphone - 从应用程序本身访问相机，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13234904/