从 Plist 加载注释到地图视图不起作用

Question

嘿伙计们，所以我可以从找到的源代码中显示注释（2）

但是，我从 plist 加载注释信息并将其正确加载（通过调试器确认）到 mapView 中，但由于某种原因，当我在模拟器中运行应用程序时，注释拒绝显示。这是相关代码：

注释标头：

#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>

@interface ArboretumAnnotation : NSObject <MKAnnotation> {
    NSString *title;
    NSString *subtitle;
    UIImage *image;

    CLLocationCoordinate2D coordinate;

}

@property (nonatomic, retain) NSString *title;
@property (nonatomic, retain) NSString *subtitle;
@property (nonatomic, retain) UIImage *image;

@property (nonatomic) CLLocationCoordinate2D coordinate;

@end

注释实现：

#import "ArboretumAnnotation.h"


@implementation ArboretumAnnotation

@synthesize title;
@synthesize subtitle;
@synthesize image;
@synthesize coordinate;

-(id)init{
    self = [super init];
    if(!self)
        return nil;

    self.title = nil;
    self.subtitle = nil;
    self.image = nil;

    return self;
}

-(id)initWithCoordinate:(CLLocationCoordinate2D)inCoord{
    self = [self init];
    self.coordinate = inCoord;
    return self;
}
@end

MapViewController 标头：

#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>


@interface MapViewController : UIViewController <MKMapViewDelegate> {
    MKMapView *mapView;
}

@property (nonatomic, retain) IBOutlet MKMapView *mapView;

- (void)showCurrentLocationButtonTapped:(id)sender;
- (void)loadAnnotations; //helper function that loads all overlay data from plist
- (void)loadOverlays; //helper function that loads all overlay data from plist
- (void)handleGesture:(UILongPressGestureRecognizer *)gestureRecognizer;

@end

MapViewController 实现：

#import "MapViewController.h"
#import "MKMapView+ZoomLevel.h"
#import "ArboretumRegionOverlay.h"
#import "ArboretumAnnotation.h"
#import "ArboretumAnnotationView.h"
#import "LocationDetailViewController.h"


#define UCD_LATITUDE 38.531728
#define UCD_LONGITUDE -121.755327

@implementation MapViewController

@synthesize mapView;


// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];
    //mapView = [[MKMapView alloc] initWithFrame:self.view.bounds];
    mapView.delegate = self;

    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Location Info" style:UIBarButtonItemStylePlain target:self action:nil];
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:100 target:self action:@selector(showCurrentLocationButtonTapped:)];


    [self loadAnnotations];

    [self loadOverlays];
    [mapView setNeedsDisplay];

    /*
    //TEST LOAD AN ANNOTATION
    //MKPointAnnotation *testAnnot = [[MKPointAnnotation alloc] init];
    ArboretumAnnotation *arboAnnot = [[ArboretumAnnotation alloc] init];
    CLLocationCoordinate2D workingCoord;
    workingCoord.latitude = 38.529977;
    workingCoord.longitude = -121.76;
    [arboAnnot setCoordinate:workingCoord];
    [arboAnnot setTitle:@"Test Title"];
    [arboAnnot setSubtitle:@"Test Subtitle"];
    [mapView addAnnotation:arboAnnot];
    [arboAnnot release];

    ArboretumAnnotation *arboAnnot2 = [[ArboretumAnnotation alloc] init];
    CLLocationCoordinate2D workingCoord2;
    workingCoord2.latitude = 38.531594;
    workingCoord2.longitude = -121.762129;
    [arboAnnot2 setCoordinate:workingCoord2];
    [arboAnnot2 setTitle:@"Test A really really really really long title Title2"];
    [arboAnnot2 setSubtitle:@"Test A really really really really long sub Subtitle2"];
    [mapView addAnnotation:arboAnnot2];
    [arboAnnot2 release];
    */

    //detects press gestures used for producing region overlay callout
    UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc] 
                                          initWithTarget:self action:@selector(handleGesture:)];
    lpgr.minimumPressDuration = 0.3;  //user must press for 1 second
    //[mapView addGestureRecognizer:lpgr];
    [lpgr release];


    //initialize the map view (location and zoom)
    CLLocationCoordinate2D centerCoord = { UCD_LATITUDE, UCD_LONGITUDE };
    [mapView setCenterCoordinate:centerCoord zoomLevel:13 animated:NO];
}

- (void)showCurrentLocationButtonTapped:(id)sender {
    NSLog(@"Showing current location.");

    if ([mapView showsUserLocation] == NO) {
        [mapView setShowsUserLocation:YES];
    }
    [mapView setCenterCoordinate:mapView.centerCoordinate zoomLevel:13 animated:YES];

}

- (void)loadAnnotations{
    //retrieve path of plist file and populate relevant types with its information
    NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"ArboretumGardens" ofType:@"plist"];
    NSDictionary *rootOfArboDataPlistDict = [[NSDictionary alloc] initWithContentsOfFile:plistPath];
    NSMutableArray *arboAnnotations = [[NSMutableArray alloc] init];

    for (NSString *key in rootOfArboDataPlistDict) {

        NSMutableDictionary *arboDict = [rootOfArboDataPlistDict objectForKey:key];

        //array containing annotation information: latitude, longitude, title, subtitle(see PermitData.plist)
        NSArray *annotationsArray = [arboDict objectForKey:@"annotations"];

        CLLocationCoordinate2D workingCoordinate;
        //loop through annotations array, creating parking annotations filled with the information found in the plist
        for(NSDictionary *annotationContainerDict in annotationsArray){

            ArboretumAnnotation *arboAnnot = [[ArboretumAnnotation alloc] init];
            workingCoordinate.latitude = [[annotationContainerDict objectForKey:@"latitude"] doubleValue];
            workingCoordinate.longitude = [[annotationContainerDict objectForKey:@"longitude"] doubleValue];
            [arboAnnot setCoordinate:workingCoordinate];
            [arboAnnot setTitle:[annotationContainerDict objectForKey:@"title"]];
            [arboAnnot setSubtitle:[annotationContainerDict objectForKey:@"subtitle"]];
            [arboAnnotations addObject:arboAnnot];
            [arboAnnot release];
        }//for
    }//for
    [mapView addAnnotations:arboAnnotations];
    [arboAnnotations release];
}

//...

- (ArboretumAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{
    if ([annotation isKindOfClass:MKUserLocation.class]) {
        //it's the built-in user location annotation(blue dot)
        return nil;
    }

    NSString *annotIdentifier = @"annotation";

    MKPinAnnotationView *recycledAnnotationView = (MKPinAnnotationView *)[self.mapView dequeueReusableAnnotationViewWithIdentifier:annotIdentifier];
    if (!recycledAnnotationView) {
        MKPinAnnotationView* customPinView = [[[MKPinAnnotationView alloc]
                                               initWithAnnotation:annotation reuseIdentifier:annotIdentifier] autorelease];

        UIImage *iconImage = [UIImage imageNamed:@"arboretum.png"];

        CGRect resizeRect;

        resizeRect.size = iconImage.size;
        CGSize maxSize = CGRectInset(self.view.bounds,
                                     10.0f,
                                     10.0f).size;
        maxSize.height -= self.navigationController.navigationBar.frame.size.height + 40.0f;
        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);

        customPinView.image = iconImage;
        //customPinView.image.frame = CGRectMake(kBorder, kBorder, kWidth - 2 * kBorder, kWidth - 2 * kBorder);
        customPinView.opaque = NO;
        //customPinView.pinColor = MKPinAnnotationColorPurple;
        customPinView.canShowCallout = YES;

        //display a disclosure icon on the right side of each annotation's callout
        UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
        customPinView.rightCalloutAccessoryView = rightButton;

        return customPinView;
    } else {
        recycledAnnotationView.annotation = annotation;
    }

    return recycledAnnotationView;

}

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (void)dealloc {
    [super dealloc];
}


@end

提前致谢！

Answer 1

事实证明，问题出在我检索坐标数据的方式上。我无意中交换了经度和纬度，这些点不会在全球地图上的任何点显示。编译器没有发出警告或错误，所以它没有被注意到......所以是的，对我来说非常尴尬，但这就是你学习的方式，对吗？

Answer 2

我不知道这是否是问题所在，但

不应该

 self = [self init];

是问题

self = [super init];