ios - 在 iOS 的另一个 View 中打开相机

Question

如何从我的 MainController.m 类中调用此方法并将图像传递给我的 MainController

CameraController.m

- (void) openCamera {
       UIImagePickerController *picker = [[UIImagePickerController alloc]init];
       picker.delegate = self;
       picker.sourcetype = UIImagePickerContrllerSourceTypeCamera;
       [self presentViewContrller:picker animated:YES completion:nil];

}

我还是 iOS 开发的新手，是否可以使用委托(delegate)？

编辑:CameraController 没有 Nib 。

Answer 1

在 CameraController.h 中添加这些行:

@protocol CameraControllerDelegate <NSObject>
- (void)didFinishCapturingImage:(UIImage*)image;
@end

并在 CameraController 类中添加一个属性(在 CameraController.h 中)

@property (nonatomic, strong) id<CameraControllerDelegate> delegate;

在MainController.h中，在接口(interface)实现中添加协议(protocol)；像这样:

@interface MainController : NSObject <CameraControllerDelegate>

在从 MainController.m 呈现/推送 CameraController 之前，添加以下行:

cameraController.delegate = self;

在MainController.m中实现didFinishCapturingImage方法。

- (void)didFinishCapturingImage:(UIImage*)image {
    //your logic
} 

在 Image Picker Controller Delegate 中，添加这一行:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    [picker dismissViewControllerAnimated:YES completion: Nil];
    UIImage *image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
    //this will send delegate callback to MainController
    [self.delegate didFinishCapturingImage:image];
}

编辑:第二个解决方案:

在 CameraController.h 中创建一个属性以保留 MainController 对象的实例:

@property (nonatomic, strong) MainController *mainController;

将 self 分配给 CameraController 实例的属性 mainController，您在其中使用 CameraController:

cameraController.mainController = self;

编辑你的openCamera方法:

- (void) openCamera {
       UIImagePickerController *picker = [[UIImagePickerController alloc]init];
       picker.delegate = self.mainController; //important line
       picker.sourcetype = UIImagePickerContrllerSourceTypeCamera;
       [self.mainController presentViewContrller:picker animated:YES completion:nil];
}

并在MainController.m

中实现以下方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    //your logic
}

不要忘记在 MainController.h 中包含 UIImagePickerControllerDelegate。

无需创建协议(protocol)和实现协议(protocol)方法..