Question

我正在处理UITableView，其中必须通过StoryBoard将数据从一个视图传递到另一个视图。数据现在正在通过故事板现在我想在第二个ViewController上传递的数据显示在UIMapView

上

我正在分享我的代码第一个VC的.h文件

{
    UITableView * addresstable;
    NSArray * addresses;


    NSString *localStringValue;
}

第一个VC的.m文件

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

    NSUInteger row = [indexPath row];
    NSString *value = [addresses objectAtIndex:row];

    localStringValue = [tableView cellForRowAtIndexPath:indexPath].textLabel.text;
    NSLog(@"ID is Here: %@", value);



    UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    detailmapViewController *vc = [mainStoryboard instantiateViewControllerWithIdentifier:@"detailmapViewController"];
    [self presentModalViewController:vc animated:YES];


    vc.PassID=value; ///assign the value after presenting
}

第二个视图的

.h文件

{
    UILabel *addresslbl;

    NSString *PassID;
}

@property(nonatomic,retain)IBOutlet UILabel* addresslbl;
@property (weak, nonatomic) IBOutlet MKMapView *mapvw;
@property (strong, nonatomic) IBOutlet CLLocationManager *locationManger;


@property (nonatomic, retain) NSString *PassID;

第二个视图的.m文件

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    addresslbl.text=PassID;
    NSLog(@"Label is Here %@",self.PassID);

}

我还希望在MAP上显示第二个VC标签的值，因为我使用了所有框架和委托文件但我不知道如何调用地图的标签文字值因为我使用以下代码

self.mapvw.delegate=self;

    NSString *location =  //---> how to put label value here <---

    CLGeocoder *geocoder = [[CLGeocoder alloc] init];
    [geocoder geocodeAddressString:location
                 completionHandler:^(NSArray* placemarks, NSError* error){
                     if (placemarks && placemarks.count > 0) {
                         CLPlacemark *topResult = [placemarks objectAtIndex:0];
                         MKPlacemark *placemark = [[MKPlacemark alloc] initWithPlacemark:topResult];

                         MKCoordinateRegion region = self.mapvw.region;
                         region.center = [(CLCircularRegion *)placemark.region center]; //placemark.region.center;
                         region.span.longitudeDelta /= 1800.0;
                         region.span.latitudeDelta /= 1800.0;

                         [self.mapvw setRegion:region animated:YES];
                         [self.mapvw addAnnotation:placemark];
                     }
                 }
     ];

Answer 1

问题是，您要在显示viewcontroller之后的值分配值。所以，它不会得到价值。

试试这个

UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
    detailmapViewController *vc = [mainStoryboard instantiateViewControllerWithIdentifier:@"detailmapViewController"];

vc.PassID=value;

[self presentModalViewController:vc animated:YES];

对于您的第二个问题，为什么不简单地将PassID值直接分配给location字符串

NSString *location = self.PassID;

或

NSString *location = addresslbl.text;

IOS：如何在UIMapView上显示标签文本值

1 个答案: