Ios 显示从当前点到从阵列中获取的所需点的直线路线的步骤

我想在我的应用程序中创建一个功能，通过该功能，我可以从当前位置到所需坐标（即浮点值）绘制一条线。请向我推荐最有效的方法。

我已经得到了所有ios问题的答案，如下所示

//要使用地理编码器显示方向…* -（无效）显示方向：（id）发件人

{
    NSString *deviceVersion   = [[UIDevice currentDevice] systemVersion];
    NSLog(@"My Device version is :%@ ",deviceVersion);


    //*********  For ios 6 supporting devices  *********
    if ([deviceVersion isEqualToString:@"6.0"])
    {

        Class itemClass = [MKMapItem class];
        if (itemClass && [itemClass respondsToSelector:@selector(openMapsWithItems:launchOptions:)]) {

            CLGeocoder *geocoder = [[CLGeocoder alloc] init];
            CLLocation *newLocation = [[CLLocation alloc]initWithLatitude:getLatitude
                                                                longitude:getLongitude];

            [geocoder reverseGeocodeLocation:newLocation
                           completionHandler:^(NSArray *placemarks, NSError *error) {

                               MKPlacemark *placeMark = [[MKPlacemark alloc] initWithPlacemark:[placemarks objectAtIndex:0]];

                               MKMapItem *mapItem = [[MKMapItem alloc]initWithPlacemark:placeMark];

                               MKMapItem *mapItem2 = [MKMapItem mapItemForCurrentLocation];

                               NSArray *mapItems = @[mapItem, mapItem2];

                               NSDictionary *options = @{
                           MKLaunchOptionsDirectionsModeKey:MKLaunchOptionsDirectionsModeDriving,
                           MKLaunchOptionsMapTypeKey:
                               [NSNumber numberWithInteger:MKMapTypeStandard],
                           MKLaunchOptionsShowsTrafficKey:@YES
                               };

                               [MKMapItem openMapsWithItems:mapItems launchOptions:options];

                           }         ];
        }
        else
        {
            UIAlertView *errorAlert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Failed to Get Your Location"delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
            [errorAlert show];

        }
    }
    //*********  For other ios supporting devices  *********
    else {

        MKCoordinateRegion region = { {0.0, 0.0 }, { 0.0, 0.0 } };
        region.center.latitude = getLatitude;
        region.center.longitude = getLongitude;

        MKCoordinateRegion currentRegion = { {0.0, 0.0 }, { 0.0, 0.0 } };
        currentRegion.center.latitude = currentLatitude;
        currentRegion.center.longitude = currentLongitude;

        region.span.longitudeDelta = 4.0f;
        region.span.latitudeDelta = 4.0f;
        currentRegion.span.longitudeDelta = 4.0f;
        currentRegion.span.latitudeDelta = 4.0f;

        CLLocationCoordinate2D start = { currentRegion.center.latitude, currentRegion.center.longitude };
        CLLocationCoordinate2D destination = { region.center.latitude, region.center.longitude };

        NSString *googleMapsURLString = [NSString stringWithFormat:@"http://maps.google.com/?saddr=%1.6f,%1.6f&daddr=%1.6f,%1.6f",start.latitude, start.longitude, destination.latitude, destination.longitude];

        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:googleMapsURLString]];

    }

}