未定义的声明错误

Question

我想开发一个iPhone应用程序，它给出了当前的经纬度值，并且出现了一些名为“未定义声明”的错误。请你帮我整理一下。提前致谢。

#import "LoginViewController.h" 
//#import <CoreLocation/CoreLocation.h> 

@interface LoginViewController() 

@end 

@implementation LoginViewController 
@synthesize locationManager; 
- (void)dealloc 
{ 
    // [super dealloc]; 
} 

- (void)didReceiveMemoryWarning 
{ 
    [super didReceiveMemoryWarning]; 
    // Dispose of any resources that can be recreated. 
} 

- (void)viewDidUnload 
{ 
    [super viewDidUnload]; 
    // Do any additional setup after loading the view, typically from a nib. 
} 

- (IBAction)Button:(id)sender 
{ 
    locationManager = [[CLLocationManager alloc] init]; 
    locationManager.delegate = self; 
    locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters; 
    locationManager.distanceFilter = kCLDistanceFilterNone; 
    [locationManager startUpdatingLocation]; 
    CLLocation *location = [locationManager location]; 
    CLLocationCoordinate2D coordinate = [location coordinate]; 
    NSString *latitude = [NSString stringWithFormat:@"%f", coordinate.latitude]; 
    NSString *longitude = [NSString stringWithFormat:@"%f", coordinate.longitude]; 
    NSLog(@"dLatitude : %@", latitude); 
    NSLog(@"dLongitude : %@", longitude); 
    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(50, 40, 250, 50)]; 
    UILabel *myLabel = [[UILabel alloc] initWithFrame:CGRectMake(50, 80, 200, 50)]; 
    UILabel *myLabel1 = [[UILabel alloc] initWithFrame:CGRectMake(50, 120, 200, 100)]; 
    myLabel.textColor = [UIColor blackColor]; 
    myLabel1.textColor = [UIColor blackColor]; 

    label.backgroundColor = [UIColor clearColor]; 
    myLabel.backgroundColor = [UIColor clearColor]; 
    myLabel1.backgroundColor = [UIColor clearColor]; 
    [myLabel setText:latitude]; 
    [myLabel1 setText:longitude]; 
    label.text = @"Current Latitude and Longitude"; 
    [self.view addSubview:label]; 
    [self.view addSubview:myLabel]; 
    [self.view addSubview:myLabel1]; 
} 
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation 
{ 
    return (interfaceOrientation == UIInterfaceOrientationPortrait); <---GETTING ERROR HERE 

} 

@end 

Answer 1

应该

return (toInterfaceOrientation == UIInterfaceOrientationPortrait);