小编Can*_*nis的帖子

我无法在MapKit中的地图上显示MKAnnotationViews.我正在使用iOS 7,现在已经在论坛和网络上搜索了几个小时,尝试了不同的示例和设置.

下面我有最基本的设置(我认为)使其工作.该应用程序包含一个ViewController,其工具栏顶部有一个按钮,其余的是MapView.该按钮触发方法zoomToUser:(UIBarButtonItem*)sender.右键单击并检查我的网点和代表似乎是正确的.我有一些NSLog语句被触发输出一些调试信息.

首先是VC:

#import "ViewController.h"
#import "Data.h"

@interface ViewController () <MKMapViewDelegate>
@property (weak, nonatomic) IBOutlet MKMapView *mapView;
- (IBAction)zoomToUser:(UIBarButtonItem *)sender;
@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.mapView.showsUserLocation = YES;
    Data *ann = [[Data alloc] init];
    [self.mapView addAnnotation:ann];
}

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

-(IBAction)zoomToUser:(UIBarButtonItem *)sender
{
    MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(self.mapView.userLocation.coordinate, 2000, 2000);
    NSLog(@"region: %f x %f",self.mapView.userLocation.coordinate.latitude,self.mapView.userLocation.coordinate.longitude);
    [self.mapView setRegion:region animated:YES ];
    NSArray *arr = self.mapView.annotations;
    for(int i = 0, max = arr.count; i < max; i++) …