从核心数据调用坐标

Question

我一直在尝试调用我已经存储到数据库中的地方的经度和纬度。我已经将存储类型设置为double。

在第一个视图控制器，我试图推坐标，并在日志中工作正常。

-(IBAction) mapsend:(id)sender 
{ 
    DiscoverAllMapViewController *fvController = [[DiscoverAllMapViewController alloc] initWithNibName:@"DiscoverAllMapViewController" bundle:nil]; 
    [self.navigationController pushViewController:fvController animated:YES]; 
    double dx = [wher.latx doubleValue]; 
    double dy = [wher.longy doubleValue]; 

    fvController.latx =[NSString stringWithFormat:@"%f",dx]; 
    fvController.longy =[NSString stringWithFormat:@"%f",dy]; 
    NSLog(@"checking latx :%@",fvController.latx); 
    [fvController release]; 
} 

现在在DisplayAllMapViewController，日志似乎总是为空。我试着将解析实例设置为NSString，NSNumber，double，但它仍然不发送任何值。

-(void)loadOurAnnotations 
{ 
    CLLocationCoordinate2D workingCoordinate; 
    MKCoordinateSpan span = {0.2, 0.2}; 
    double xx = [latx doubleValue]; 
    double yy = [longy doubleValue]; 
    NSLog(@"check latx :%f",xx); 
    workingCoordinate.latitude = xx; 
    workingCoordinate.longitude = yy; 
    MKCoordinateRegion region = {workingCoordinate, span}; 
    DiscoverAllMapAnnotation *appleStore1 = [[DiscoverAllMapAnnotation alloc] init]; 
    [appleStore1 setCoordinate:workingCoordinate]; 
    [appleStore1 setTitle:@"Kota Kinabalu"]; 
    [appleStore1 setSubtitle:@"BOMB!!!!!"]; 
    [appleStore1 setAnnotationType:DiscoverAllMapAnnotationType1]; 

    mapView.showsUserLocation=TRUE; 
    [mapView addAnnotation:appleStore1]; 
    [mapView setRegion:region]; 
    [appleStore1 release]; 


} 

请看看..谢谢

Answer 1

的DiscoverAllMapViewController的viewDidLoad只要你做pushViewController情况是你设置了latx和longy属性之前。

将pushViewController拨到后的属性被设置（就在fvController release之前）。