Question

在尝试呈现联系人编辑器VC时，我收到错误消息

Warning: Attempt to present <UINavigationController: 0x15fe273f0> on <UINavigationController: 0x15fe0e730> while a presentation is in progress!

我相信这是因为我的UIImagePickerController仍然有效。

这是我的didFinish方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    UIImage *image = info[UIImagePickerControllerOriginalImage];
animated:YES];
    [picker dismissViewControllerAnimated:YES completion:NULL];
    [self scanWithImage:image];

}

正如您所看到的那样，第二条消息应该忽略VC，但它不会消失，并且它会一直持续到应用程序执行结束。

scanWithImage:最终调用showNewPersonViewController就是这个方法：

-(void)showNewPersonViewController
{
    ABNewPersonViewController *picker = [[ABNewPersonViewController alloc] init];
    picker.displayedPerson = _person;
    picker.newPersonViewDelegate = self;

    UINavigationController *navigation = [[UINavigationController alloc] initWithRootViewController:picker];
    // Change status bar back to black due to white contact creation.
    [UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleDefault;

    [self presentViewController:navigation animated:YES completion:nil];
}

在该方法的最后一行，我收到错误消息，然后应用程序完成执行并返回主VC。

如何避免这种情况并正确显示联系人创建VC？

Answer 1

让我们试试：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
  UIImage *image = info[UIImagePickerControllerOriginalImage];
  // I think picker should change to self == this class dismisses, not picker dismisses
  [self dismissViewControllerAnimated:YES completion:nil];
 }

 // should implement [self scanWithImage:image]; in parent class which contains VC has pickerView. 
 // Because after dismissing, VC which contains picker is dealloc, how can you call [self presentViewController:navigation animated:YES completion:nil];

我认为这可以帮到你

Answer 2

我认为你在动画中同时呈现两个VC。在呈现或解除时将VC的一个动画设置为NO，并查看警告是否消失。

我不是100％肯定，但是如果你想要两个动画，你应该在第一个完成块上运行第二个动画，或者使用计时器来延迟第二个视图控制器的导航开始。

警告：尝试出席

2 个答案: