ios - MKDirectionsResponse 对象给出空值

Question

响应对象为 null，代码未执行。

MKPlacemark *source=[[MKPlacemark alloc]initWithCoordinate:sourceloc addressDictionary:[NSDictionary dictionaryWithObjectsAndKeys:@"",@"", nil]];  

MKPlacemark *source=[[MKPlacemark alloc]initWithCoordinate:sourceloc addressDictionary:[NSDictionary dictionaryWithObjectsAndKeys:@"",@"", nil]];

MKMapItem *srcmapItem=[[MKMapItem alloc]initWithPlacemark:source];

 [srcmapItem setName:@""];

MKPlacemark *destination=[[MKPlacemark alloc]initWithCoordinate:destinationloc addressDictionary:[NSDictionary dictionaryWithObjectsAndKeys:@"",@"", nil]];
MKMapItem *desmapItem=[[MKMapItem alloc]initWithPlacemark:destination];
 [desmapItem setName:@""];

MKDirectionsRequest *request=[[MKDirectionsRequest alloc]init];

 [request setSource:srcmapItem];
 [request setDestination:desmapItem];
 [request setTransportType:MKDirectionsTransportTypeWalking];

MKDirections *direction = [[MKDirections alloc]initWithRequest:request];

 [direction calculateDirectionsWithCompletionHandler:^(MKDirectionsResponse *response, NSError *error) {

    NSLog(@"response = %@",response);
    NSArray *arrRoutes = [response routes];

    [arrRoutes enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

        MKRoute *rout = obj;

        MKPolyline *line = [rout polyline];
        [self.routeMap addOverlay:line];
        NSLog(@"Rout Name : %@",rout.name);
        NSLog(@"Total Distance (in Meters) :%f",rout.distance);

        NSArray *steps = [rout steps];

        NSLog(@"Total Steps : %lu",(unsigned long)[steps count]);

        [steps enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
            NSLog(@"Rout Instruction : %@",[obj instructions]);
            NSLog(@"Rout Distance : %f",[obj distance]);
        }];
    }];
}];

Answer 1

苹果官方中的Directions Feature Availability list

https://www.apple.com/in/ios/feature-availability/#maps-directions

因此根据苹果文档，此功能在印度不可用。这是获得 NULL 响应的唯一原因。

您可以使用谷歌地图但有一些限制，Google Maps Geocoding API 具有以下限制。

https://developers.google.com/maps/documentation/geocoding/usage-limits

其他替代解决方案是使用其他开源。