ios - 使用未声明的标识符 'startCameraControllerFromViewController'

Question

我有一个打开相机应用程序的按钮，以便用户可以将其保存为 UIImage。我收到使用未声明的标识符错误，但我不知道为什么。任何帮助，将不胜感激。

#pragma mark - Camera Button

- (IBAction)cameraButton:(id)sender {
    [self startCameraControllerFromViewController:self usingDelegate:self];
}


#pragma mark - Save picture callbacks

- (void) image:(UIImage *) image didFinishSavingWithError:(NSError *)error contextInfo:(void *) contextInfo {
    if(error) {



#pragma mark - Get picture by taking picture

- (BOOL) startCameraControllerFromViewController: (UIViewController*) controller usingDelegate: (id <UIImagePickerControllerDelegate, UINavigationControllerDelegate>) delegate {
    if (([UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypeCamera] == NO) || (delegate == nil) || (controller == nil))
        return NO;

    UIImagePickerController *cameraUI = [[UIImagePickerController alloc] init];
    cameraUI.sourceType = UIImagePickerControllerSourceTypeCamera;

    cameraUI.delegate = delegate;
    [controller presentViewController:cameraUI animated:YES completion:nil];
    return YES;
}

- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    UIImage * image = info[UIImagePickerControllerOriginalImage];
    _label.text = [NSString stringWithFormat:@"Have image: %d x %d", (int) image.size.width, (int) image.size.height];
    _imageView.image = image;
    [self dismissViewControllerAnimated:YES completion:nil];
}

- (void) imagePickerControllerDidCancel:(UIImagePickerController *)picker {
    [self dismissViewControllerAnimated:YES completion:nil];
}

    }
}

@end

Answer 1

看起来只是一个语法错误:

- (void) image:(UIImage *) image didFinishSavingWithError:(NSError *)error contextInfo:(void *) contextInfo {
    if(error) {



#pragma mark - Get picture by taking picture

永远不要关闭 if 语句两边的大括号。

将其更改为:

- (void) image:(UIImage *) image didFinishSavingWithError:(NSError *)error contextInfo:(void *) contextInfo {
    if(error) {
        NSLog(@"Error saving image: %@", error);
    }
}

#pragma mark - Get picture by taking picture