iphone - Objective-C 类引用 : Symbols not found error

Question

我已经在这个 iPhone 应用程序上工作了一段时间，我已经完全完成并开始工作了。我正在扩展的项目是从我的教授也授予我访问权限的在线颠覆存储库下载的。我不小心没有下载“根”副本或类似的东西，所以我无法向存储库提交任何更改。在导师的帮助下，我今天下载了根副本并将我所有的类(class)文件添加到其中，以便我可以提交更改。但是，我现在遇到了 3 个我以前从未见过的奇怪错误:

undefined symbol :

"_OBJC_CLASS_$_mapListViewController", referenced from: objc-class-ref-to-mapListViewController in mapViewController.o

"_OBJC_CLASS_$_mapParser", referenced from: objc-class-ref-to-mapParser in mapViewController.o

"_OBJC_CLASS_$_mapTabViewController", referenced from: objc-class-ref-to-mapTabViewController in mapViewController.o

ld: symbol(s) not found collect2: ld returned 1 exit status

这正是我收到的错误消息。我没有更改今天早上完全运行的版本的任何代码。有什么建议吗？ mapViewController 文件似乎是导致问题的原因，所以这里也是:

#import "mapViewController.h"
#import "locationDetailViewController.h"
#import "DPUAnnotation.h"
#import "mapParser.h"
#import "mapListViewController.h"
#import "mapTabViewController.h"

@implementation mapViewController
@synthesize locationManager, mapView, mapAnnotations, mParser, mapListView, tabView;

@class DPUAnnotation;

+ (CGFloat)annotationPadding;
{
    return 10.0f;
}
+ (CGFloat)calloutHeight;
{
    return 40.0f;
}

- (void)gotoLocation
{
    // start off by default at DePauw campus
    MKCoordinateRegion newRegion;
    newRegion.center.latitude = 39.639348;
    newRegion.center.longitude = -86.861231;
    newRegion.span.latitudeDelta = 0.006776;
    newRegion.span.longitudeDelta = 0.006291;

    [self.mapView setRegion:newRegion animated:YES];
}

- (void)viewDidLoad {

    self.title = @"Map";
    mapView.mapType = MKMapTypeHybrid;
    mapView.showsUserLocation = YES;

    mapListView = [[mapListViewController alloc] initWithNibName:@"mapListView" bundle:nil];
    tabView = [[mapTabViewController alloc] initWithNibName:@"mapTabViewController" bundle:nil];

    if (mapAnnotations == nil)
    {
        self.mapAnnotations = [NSMutableArray array];
    } 
    else 
    {
        [mapAnnotations removeAllObjects];
    }

    UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"btn_home.png"] style:UIBarButtonItemStyleBordered target:self action:@selector(mainpageClicked)];
    [self.navigationItem setLeftBarButtonItem:backButton];

    UIBarButtonItem *mapListButton = [[UIBarButtonItem alloc] initWithTitle:@"Building List" style:UIBarButtonItemStylePlain target:self action:@selector(pushMapList)];
    [self.navigationItem setRightBarButtonItem: mapListButton];

    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyBest;
    [locationManager startUpdatingLocation];

    [self gotoLocation];

    self.mParser = [[[mapParser alloc] init] autorelease];
    self.mParser.delegate = self;
    [self.mParser start];

    [super viewDidLoad];
}

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

- (void)dealloc 
{
    [mapView release];
    [locationManager release];
    [mapAnnotations release];

    [super dealloc];
}

/*
 * Returns the User to the main Application Page
 */
- (IBAction)mainpageClicked
{
    NSLog(@"Return To Main page Clicked");
    [self.parentViewController dismissModalViewControllerAnimated:YES];
    [self.navigationController release];
}

- (IBAction) pushMapList
{   
    tabView = [[mapTabViewController alloc] initWithNibName:@"mapTabViewController" bundle:nil];
    tabView.mapAnnotations2 = mapAnnotations;
    [self.navigationController pushViewController:tabView animated:YES];
    [tabView release];
}

- (IBAction)addAnnotation
{   
    [self.mapView removeAnnotations:self.mapView.annotations];

    for (int i = 0; i < [mapAnnotations count]; i++)
        [mapView addAnnotation:[mapAnnotations objectAtIndex:i]];
    NSLog(@"BLAH BLAH BLAH PLEASE PRINT");
    if([mapAnnotations count] == 0)
        NSLog(@"array is empty");
}

- (void)showDetails:(id)sender
{
    NSInteger selectedIndex = [sender tag];
    DPUAnnotation *selectedObject = [mapAnnotations objectAtIndex:selectedIndex];

    [self.navigationController setToolbarHidden:YES animated:NO];

    NSURL *url = [NSURL URLWithString: selectedObject.url];

    locationDetailViewController *locationDetailView;
    locationDetailView = [[locationDetailViewController alloc] initWithNibName:@"mapDetailView" bundle:nil];
    [self.navigationController pushViewController:locationDetailView animated:YES];
    [locationDetailView.webView loadRequest: [NSURLRequest requestWithURL:url]];
    [locationDetailView release];

    [selectedObject release];
}

- (MKAnnotationView *)mapView:(MKMapView *)theMapView viewForAnnotation:(id <MKAnnotation>)annotation
{   
    // if it's the user location, just return nil.
    if ([annotation isKindOfClass:[MKUserLocation class]])
        return nil;

    if([[annotation subtitle] isEqualToString:@"Academic"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *academicImage = [UIImage imageNamed:@"academic.png"];

            CGRect resizeRect;

            resizeRect.size = academicImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [academicImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    else if([[annotation subtitle] isEqualToString:@"Administrative"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *administrativeImage = [UIImage imageNamed:@"administrative.png"];

            CGRect resizeRect;

            resizeRect.size = administrativeImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [administrativeImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    else if([[annotation subtitle] isEqualToString:@"University Housing"] || [[annotation subtitle] isEqualToString:@"Residence Halls"] || [[annotation subtitle] isEqualToString:@"University Duplexes"] || [[annotation subtitle] isEqualToString:@"Greek Housing"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *housingImage = [UIImage imageNamed:@"housing.png"];

            CGRect resizeRect;

            resizeRect.size = housingImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [housingImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    else if([[annotation subtitle] isEqualToString:@"Other"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *otherImage = [UIImage imageNamed:@"other.png"];

            CGRect resizeRect;

            resizeRect.size = otherImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [otherImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    else if([[annotation subtitle] isEqualToString:@"Fields"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *athleticsImage = [UIImage imageNamed:@"athletics.png"];

            CGRect resizeRect;

            resizeRect.size = athleticsImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [athleticsImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    else if([[annotation subtitle] isEqualToString:@"Landmarks"])
    {
        // try to dequeue an existing pin view first
        static NSString* annotationIdentifier = @"annotationIdentifier";
        MKPinAnnotationView* pinView = (MKPinAnnotationView *)[theMapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier];

        if (!pinView)
        {
            MKAnnotationView *annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation
                                                                             reuseIdentifier:annotationIdentifier] autorelease];
            annotationView.canShowCallout = YES;

            UIImage *landmarkImage = [UIImage imageNamed:@"landmark.png"];

            CGRect resizeRect;

            resizeRect.size = landmarkImage.size;
            CGSize maxSize = CGRectInset(self.view.bounds,
                                         [mapViewController annotationPadding],
                                         [mapViewController annotationPadding]).size;
            maxSize.height -= self.navigationController.navigationBar.frame.size.height + [mapViewController calloutHeight];
            if (resizeRect.size.width > maxSize.width)
                resizeRect.size = CGSizeMake(maxSize.width, resizeRect.size.height / resizeRect.size.width * maxSize.width);
            if (resizeRect.size.height > maxSize.height)
                resizeRect.size = CGSizeMake(resizeRect.size.width / resizeRect.size.height * maxSize.height, maxSize.height);

            resizeRect.origin = (CGPoint){0.0f, 0.0f};
            UIGraphicsBeginImageContext(resizeRect.size);
            [landmarkImage drawInRect:resizeRect];
            UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

            annotationView.image = resizedImage;
            annotationView.opaque = NO;

            UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            NSInteger annotationValue = [self.mapAnnotations indexOfObject:annotation];
            rightButton.tag = annotationValue;
            [rightButton addTarget:self action:@selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
            annotationView.rightCalloutAccessoryView = rightButton;

            return annotationView;
        }
        else
        {
            pinView.annotation = annotation;
        }
        return pinView;
    }

    return nil;
}

#pragma mark <mapParser> Implementation

- (void)parser:(NSXMLParser *)parser didFailWithError:(NSError *)parseError {

}

- (void)parserDidEndParsingData:(mapParser *)parser
{
    [self addAnnotation];

    tabView.mapAnnotations2 = mapAnnotations;

    self.mParser = nil;
    [mParser release];
}

- (void)parser:(mapParser *)parser didParseItem:(NSArray *)parsedItem
{
    NSLog(@"Did Parse Map Item");

    [self.mapAnnotations addObjectsFromArray:parsedItem];
}

- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error {}
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark {}

@end

Answer 1

您的项目文件中很可能缺少这三个类。检查 XCode 项目中的 Classes 组，看看这三个文件是否存在。如果没有，则右键单击“类”组，然后单击“添加”>“现有文件”以添加它们。

如果将文件添加到项目中，请确保将这些缺失类的实现 (.m) 文件添加到已编译的源代码中。要检查这一点，请展开组 Targets > your application target > Compile Sources，然后查看文件是否存在。如果没有，请右键单击“编译源代码”，然后转到 Add > Existing Files 添加它们。另一种可能更快的方法是为每个缺失的类选择 .m 文件，然后查看是否选中了最右侧的靶心复选框。如果没有，则检查它，它会自动添加到编译源中。