使用UIImagePickerController拍摄两张照片

Question

在我的应用程序中，我正在使用UIImagePickerController拍照，当拍照时，应用程序会显示另一个视图控制器，我可以在其中向用户添加农场。在这个视图控制器中，我会给用户重新拍照的机会，所以我创建了一个按钮来调用UIImagePickerController，我使用了以下代码：

- (IBAction)buttonRetakePic:(UIBarButtonItem *)sender {
    UIImagePickerController *picker = [[UIImagePickerController alloc]init];
    picker.delegate = self;
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    picker.cameraDevice = UIImagePickerControllerCameraDeviceFront;
    [self presentViewController:picker animated:YES completion:nil];
}
#pragma mark imagePicker delegate
- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    NSError *error;
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *imagePath = [documentsDirectory stringByAppendingPathComponent:@"/Immagini"];
    if (![[NSFileManager defaultManager] fileExistsAtPath:imagePath]) {
        [[NSFileManager defaultManager] createDirectoryAtPath:imagePath withIntermediateDirectories:NO attributes:nil error:&error];
    }
    NSArray *fileList = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:imagePath error:nil];
    long count = [fileList count];
    NSString *filename = [NSString stringWithFormat:@"Nivea_%ld.jpg", count++];
    NSString *imagePathWithFileName = [imagePath stringByAppendingPathComponent:filename];
    [[NSUserDefaults standardUserDefaults]setObject:filename forKey:@"Filename"];
    [[NSUserDefaults standardUserDefaults] synchronize];
    UIImage *picture = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
    NSData *thumbData = UIImageJPEGRepresentation(picture, 1);
    [thumbData writeToFile:imagePathWithFileName atomically:YES];
    UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    UIViewController *vc = [storyBoard instantiateViewControllerWithIdentifier:@"Picture"];
    [[[[UIApplication sharedApplication] delegate] window] setRootViewController:vc];
}

但当我按下按钮Back时，它会向我显示带有旧照片的UIImagePickerController，我可以在看不到相机上发生了什么的情况下拍照。为什么它不起作用？怎么了？还有其他方法可以重拍照片吗？感谢

Answer 1

首先关闭之前提供的imagePickerController。然后在完成时尝试呈现新的imagePickerController。

Answer 2

您只是在调用UIImagePicker，它不会打开新的。您将不得不放弃已收到的数据。或者重新加载数据。