Ce qui suit viewDidLoadva (1) mis en deux endroits, (2) supprimer toutes les annotations précédentes, et (3) l' utilisateur d'appel des fonctions d'assistance définies (pour obtenir des points de route et de tracer le parcours).
-(void)viewDidLoad
{
[super viewDidLoad];
// Origin Location.
CLLocationCoordinate2D loc1;
loc1.latitude = 29.0167;
loc1.longitude = 77.3833;
Annotation *origin = [[Annotation alloc] initWithTitle:@"loc1" subTitle:@"Home1" andCoordinate:loc1];
[objMapView addAnnotation:origin];
// Destination Location.
CLLocationCoordinate2D loc2;
loc2.latitude = 19.076000;
loc2.longitude = 72.877670;
Annotation *destination = [[Annotation alloc] initWithTitle:@"loc2" subTitle:@"Home2" andCoordinate:loc2];
[objMapView addAnnotation:destination];
if(arrRoutePoints) // Remove all annotations
[objMapView removeAnnotations:[objMapView annotations]];
arrRoutePoints = [self getRoutePointFrom:origin to:destination];
[self drawRoute];
[self centerMap];
}
Ce qui suit est la MKMapViewDelegateméthode, qui tire overlay (iOS 4.0 et versions ultérieures).
/* MKMapViewDelegate Meth0d -- for viewForOverlay*/
- (MKOverlayView*)mapView:(MKMapView*)theMapView viewForOverlay:(id <MKOverlay>)overlay
{
MKPolylineView *view = [[MKPolylineView alloc] initWithPolyline:objPolyline];
view.fillColor = [UIColor blackColor];
view.strokeColor = [UIColor blackColor];
view.lineWidth = 4;
return view;
}
La fonction suivante obtenir à la fois les lieux et préparer URL pour obtenir tous les points de l'itinéraire. Et bien sûr, appellera stringWithURL.
/* This will get the route coordinates from the Google API. */
- (NSArray*)getRoutePointFrom:(Annotation *)origin to:(Annotation *)destination
{
NSString* saddr = [NSString stringWithFormat:@"%f,%f", origin.coordinate.latitude, origin.coordinate.longitude];
NSString* daddr = [NSString stringWithFormat:@"%f,%f", destination.coordinate.latitude, destination.coordinate.longitude];
NSString* apiUrlStr = [NSString stringWithFormat:@"http://maps.google.com/maps?output=dragdir&saddr=%@&daddr=%@", saddr, daddr];
NSURL* apiUrl = [NSURL URLWithString:apiUrlStr];
NSError *error;
NSString *apiResponse = [NSString stringWithContentsOfURL:apiUrl encoding:NSUTF8StringEncoding error:&error];
NSString* encodedPoints = [apiResponse stringByMatching:@"points:\\\"([^\\\"]*)\\\"" capture:1L];
return [self decodePolyLine:[encodedPoints mutableCopy]];
}
Le code suivant est la vraie magie (décodeur pour la réponse que nous avons obtenu de l'API). Je ne modifierait pas ce code à moins que je sais ce que je fais :)
- (NSMutableArray *)decodePolyLine:(NSMutableString *)encodedString
{
[encodedString replaceOccurrencesOfString:@"\\\\" withString:@"\\"
options:NSLiteralSearch
range:NSMakeRange(0, [encodedString length])];
NSInteger len = [encodedString length];
NSInteger index = 0;
NSMutableArray *array = [[NSMutableArray alloc] init];
NSInteger lat=0;
NSInteger lng=0;
while (index < len) {
NSInteger b;
NSInteger shift = 0;
NSInteger result = 0;
do {
b = [encodedString characterAtIndex:index++] - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
NSInteger dlat = ((result & 1) ? ~(result >> 1) : (result >> 1));
lat += dlat;
shift = 0;
result = 0;
do {
b = [encodedString characterAtIndex:index++] - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
NSInteger dlng = ((result & 1) ? ~(result >> 1) : (result >> 1));
lng += dlng;
NSNumber *latitude = [[NSNumber alloc] initWithFloat:lat * 1e-5];
NSNumber *longitude = [[NSNumber alloc] initWithFloat:lng * 1e-5];
printf("\n[%f,", [latitude doubleValue]);
printf("%f]", [longitude doubleValue]);
CLLocation *loc = [[CLLocation alloc] initWithLatitude:[latitude floatValue] longitude:[longitude floatValue]];
[array addObject:loc];
}
return array;
}
Cette fonction dessinera un itinéraire et ajoutera une superposition.
- (void)drawRoute
{
int numPoints = [arrRoutePoints count];
if (numPoints > 1)
{
CLLocationCoordinate2D* coords = malloc(numPoints * sizeof(CLLocationCoordinate2D));
for (int i = 0; i < numPoints; i++)
{
CLLocation* current = [arrRoutePoints objectAtIndex:i];
coords[i] = current.coordinate;
}
self.objPolyline = [MKPolyline polylineWithCoordinates:coords count:numPoints];
free(coords);
[objMapView addOverlay:objPolyline];
[objMapView setNeedsDisplay];
}
}
Le code suivant Centrer la carte.
- (void)centerMap
{
MKCoordinateRegion region;
CLLocationDegrees maxLat = -90;
CLLocationDegrees maxLon = -180;
CLLocationDegrees minLat = 90;
CLLocationDegrees minLon = 180;
for(int idx = 0; idx < arrRoutePoints.count; idx++)
{
CLLocation* currentLocation = [arrRoutePoints objectAtIndex:idx];
if(currentLocation.coordinate.latitude > maxLat)
maxLat = currentLocation.coordinate.latitude;
if(currentLocation.coordinate.latitude < minLat)
minLat = currentLocation.coordinate.latitude;
if(currentLocation.coordinate.longitude > maxLon)
maxLon = currentLocation.coordinate.longitude;
if(currentLocation.coordinate.longitude < minLon)
minLon = currentLocation.coordinate.longitude;
}
region.center.latitude = (maxLat + minLat) / 2;
region.center.longitude = (maxLon + minLon) / 2;
region.span.latitudeDelta = maxLat - minLat;
region.span.longitudeDelta = maxLon - minLon;
[objMapView setRegion:region animated:YES];
}
J'espère que cela aiderait quelqu'un.
