标签一直显示 plist 中的最后一项

Question

我正在构建一个 iPhone 应用程序，而我的标签一直在抓取我 plist 中的最后一项。应用程序的第一部分显示带有注释的地图。注释——纬度和经度以及标题也都是从同一个 plist 中提取的。

这是我的代码：

 #import "myMapViewController.h"
    #import "MapViewAnnotation.h"

    @interface myMapViewController ()
    @property NSArray *states;
    //@property NSString *nameString;
    //@property NSString *zipString;
    //@property NSString *subtitleString;
   //@property NSString *zipString;
    @end

    @implementation myMapViewController

    @synthesize mapView;



    - (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    //self.mapView.showsUserLocation = YES;  //showsUserLocation = YES;
    self.mapView.delegate = self;
    [self.mapView setUserTrackingMode:MKUserTrackingModeFollow animated: YES];
    [self.mapView addAnnotations:[self createAnnotations]];

    //[self zoomToLocation];
}

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

- (NSMutableArray *)createAnnotations
{
    NSMutableArray *annotations = [[NSMutableArray alloc] init];

    NSString *path = [[NSBundle mainBundle]pathForResource:@"States" ofType:@"plist"];
    NSArray *rootLevel = [[NSMutableArray alloc]initWithContentsOfFile:path];

    int count = rootLevel.count;

    for (int i = 0; i < count; i++){

        NSDictionary *secondLevel = [rootLevel objectAtIndex:i];
        // NSArray *state = [secondLevel valueForKey:@"State"];
        NSArray *stores = [secondLevel valueForKey:@"Stores"];


        for (NSDictionary *row in stores) {
            NSString *latitude = [row objectForKey:@"Latitude"];
            NSString *longitude = [row objectForKey:@"Longitude"];
            NSString *title = [row objectForKey:@"Name"];

            NSString *nameString = [row objectForKey:@"Number"];
            NSString *zipString = [row objectForKey:@"Zip"];
            NSString *subtitle = [row objectForKey:@"Address1"];

            //Create coordinates from the latitude and longitude values
            CLLocationCoordinate2D coord;
            coord.latitude = latitude.doubleValue;
            coord.longitude = longitude.doubleValue;

            MapViewAnnotation *annotation = [[MapViewAnnotation alloc] initWithTitle:title AndCoordinate:coord AndZipString:zipString AndNameString:nameString AndSubSubtitle:subtitle];

            [annotations addObject:annotation];

            //set label


        }
    }
    return annotations;
}

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if([[segue identifier] isEqualToString:@"showStoreDetails"])
    {



        MKAnnotationView *annotationView = sender;
        id<MKAnnotation> ann = annotationView.annotation;
       [segue.destinationViewController setNameString:ann.title];
       [segue.destinationViewController setZipString:ann.title];
        NSLog(@"log %@", annotationView.annotation.subtitle);

    }
}

- (MKAnnotationView *)mapView:(MKMapView *)sender viewForAnnotation:(id < MKAnnotation >)annotation
{
    static NSString *reuseId = @"StandardPin";

    MKPinAnnotationView *aView = (MKPinAnnotationView *)[sender
                                                         dequeueReusableAnnotationViewWithIdentifier:reuseId];

    if (annotation == mapView.userLocation){
        return nil; //default to blue dot
    }

    if (aView == nil)
    {
        aView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation
                                                reuseIdentifier:reuseId];
        aView.rightCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
        aView.canShowCallout = YES;
        //aView.animatesDrop = YES;
    }

    aView.annotation = annotation;
    return aView;
}

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view
calloutAccessoryControlTapped:(UIControl *)control
{
    [self performSegueWithIdentifier:@"showStoreDetails" sender:view];
    NSLog(@"accessory button tapped for annotation %@", view.annotation.title);

}

- (void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views {
    for(MKAnnotationView *annotationView in views) {
        if(annotationView.annotation == mv.userLocation) {
            MKCoordinateRegion region;
            MKCoordinateSpan span;

            span.latitudeDelta=0.7;
            span.longitudeDelta=0.7;

            CLLocationCoordinate2D location=mv.userLocation.coordinate;

            region.span=span;
            region.center=location;

            [mv setRegion:region animated:TRUE];
            [mv regionThatFits:region];
        }
    }
}

@end

Answer 1

问题似乎是在prepareForSegue 中，您将self.nameString 发送到destinationViewController，但该变量仅包含读取的最后一项。

请注意，在calloutAccessoryControlTapped 中，您调用performSegueWithIdentifier 时将sender 作为view（即所选注释的视图）但在prepareForSegue ，您没有使用sender。

您应该在prepareForSegue 中使用sender 而不是self.nameString。

有关详细示例，请参阅MKAnnotationView Push to View Controller when DetailDesclosure Button is Clicked。

prepareForSegue 中的更新代码可能如下所示：

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if([[segue identifier] isEqualToString:@"showStoreDetails"])
    {
        MKAnnotationView *annotationView = sender;
        id<MKAnnotation> ann = annotationView.annotation;
        [segue.destinationViewController setNameString:ann.title];
    }
}

Answer 2

这很简单。您的内部循环负责将文本分配给标签。这两个循环遍历所有记录并不断将名称分配给 nameString 删除第一个记录的标签

self.nameString = nameString;

因此只存储最后一个字符串。

希望这会有所帮助。

谢谢， 库纳尔

Answer 3

看起来您实际上并没有为MapViewAnnotation 对象提供该位置的标签。

当您遍历 plist 中的数据时，标签上唯一发生的事情是将其设置为 self.nameString，这将不断被循环的每次迭代覆盖。

不确定您的代码到底想做什么，但看起来您对 name 值做得不够，无法实现您想要的。

Answer 4

当您遍历您的 plist 时，您需要一个数组来存储您的 namestring 而不是简单的 self.namestring NSString。