我尝试按照 Apple 的建议将 ViewController 更改为将设备方向从纵向更改为横向。执行代码时，我总是收到错误消息：
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Application tried to present a nil modal view controller on target.
我只是无法弄清楚问题是什么。这是执行终止的部分（PortraitViewController 的一部分）：
- (void)updateLandscapeView
{
UIDeviceOrientation deviceOrientation = [UIDevice currentDevice].orientation;
if (UIDeviceOrientationIsLandscape(deviceOrientation) && self.presentedViewController == nil){
if (!self.resultViewLandscapeViewController){
[self.storyboard instantiateViewControllerWithIdentifier:@"LandscapeViewController"];
NSLog(@"LandscapeView initiated"); //this is called when device is turned
}
[self presentViewController:self.resultViewLandscapeViewController animated:YES completion:NULL];
//after the code above the execution is interrupted and the error message is thrown
}
else if (deviceOrientation == UIDeviceOrientationPortrait && self.presentedViewController != nil){
[self dismissViewControllerAnimated:YES completion:NULL];
}
}