有关Aviary SDK的问题

在ios中使用Aviary SDK,我按照教程中的步骤进行，但是在调用Viewdidload中的方法：

- (void)displayEditorForImage:(UIImage *)imageToEdit
{
    AFPhotoEditorController *editorController = [[AFPhotoEditorController alloc] initWithImage:imageToEdit];
    [editorController setDelegate:self];
    [self presentViewController:editorController animated:YES completion:nil];
}

报出了如下警告：

Warning: Attempt to present <AFSDKViewController: 0x7e1aeb0> on <ViewController: 0x7934af0> whose view is not in the window hierarchy!