ios - 警告 : Attempt to present uiimagepickercontroller while a presentation is in progress

Question

关闭相机后。它给了我这个警告:在演示过程中尝试继续演示!

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

我不知道这是不是个大问题。

更多代码:

- (void) viewWillAppear:(BOOL)animated
{
    [self takePicture];
}


- (void) takePicture
{
    UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
        [imagePickerController setSourceType:UIImagePickerControllerSourceTypeCamera];
    } else
        [imagePickerController setSourceType:UIImagePickerControllerSourceTypePhotoLibrary];

    imagePickerController.delegate = self;
    [self presentViewController:imagePickerController animated:YES completion:nil];
}


- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    [self dismissViewControllerAnimated:NO completion:nil];
}

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
    [self dismissViewControllerAnimated:NO completion:nil];
}

顺便说一句，“dismissModalViewController”已被弃用。

修复: 一旦有新 View ，将调用 ViewWillAppear。这就是问题所在

Answer 1

您不应该从 viewWillAppear 中呈现任何 Controller ，因为当前 View Controller 的呈现尚未完成。

从 viewDidAppear 调用 takePicture 因为 viewDidAppear 将在 Controller 呈现完成后被调用。

- (void)viewDidAppear:(BOOL)animated{
    [super viewDidAppear:animated];
    [self takePicture];
}

希望对您有所帮助。