如何存储坐标- iOS

I have an iOS application which parses some data from a JSON feed. One of the bit of downloaded data is a set of coordinates. I am trying to get those coordinates and display them on a MapView in iOS. But I get the following error:

我有一个iOS应用程序，它解析JSON提要中的一些数据。下载的数据之一是一组坐标。我正在尝试获取这些坐标并在iOS的MapView上显示它们。但是我得到了以下错误:

initializing 'cllocationcoordinate2d' with an expression of incompatible type 'id'

初始化'cllocationcoordinate2d'与不兼容类型'id'的表达式

Here is my code:

这是我的代码:

    int choose = 4;
    NSArray *location_lat = [[[res objectForKey:@"data"] valueForKey:@"location"] valueForKey:@"latitude"];
    NSArray *location_long = [[[res objectForKey:@"data"] valueForKey:@"location"] valueForKey:@"longitude"];

    NSLog(@"\n\nLat:%f Lon:%f", [location_lat[choose] doubleValue], [location_long[choose] doubleValue]);

    CLLocationCoordinate2D lat = [location_lat[choose] doubleValue];
    CLLocationCoordinate2D lon = [location_long[choose] doubleValue];

    MKCoordinateRegion region = { {0.0, 0.0}, {0.0, 0.0} };
    region.center.latitude = lat;
    region.center.longitude = lon;
    region.span.longitudeDelta = 0.01f;
    region.span.latitudeDelta = 0.01f;
    [map setRegion:region animated: YES];

    ContentView *ann = [[ContentView alloc] init];
    ann.title = @"Current Location";
    ann.subtitle = @"";
    ann.coordinate = region.center;
    [map addAnnotation:ann];

I don't understand what I am doing wrong... Please help.

我不明白我做错了什么……请帮助。

Thanks, Dan.

谢谢你,丹。

2 个解决方案

#1

Latitude and longitude do not appear to be of type CLLocationCoordinate2D, it looks like they are doubles. Try this:

纬度和经度看起来不是CLLocationCoordinate2D类型，看起来它们是双精度的。试试这个:

double lat = [location_lat[choose] doubleValue];
double lon = [location_long[choose] doubleValue];

CLLocationCoordinate2D represents both latitude and longitude, so you can also do this:

CLLocationCoordinate2D同时表示纬度和经度，因此您还可以这样做:

CLLocationCoordinate2D center = CLLocationCoordinate2DMake([location_lat[choose] doubleValue], location_long[choose] doubleValue]);

MKCoordinateRegion region = { {0.0, 0.0}, {0.0, 0.0} };
region.center = center;

#2

Use this macro:

使用这个宏:

 CLLocationCoordinate2D cord = CLLocationCoordinate2DMake(x, y);

#1