Display multiple locations on google map. IOS/Objective-C

Question

I'm using google maps sdks to display locations on IOS app that i'm working on. Displaying single location works fine, but when i try to display multiple locations on a single map it gives a white screen. I have a restaurantsData object that consists of information pertaining to an array of restaurants (along with latitude and longitude for each). Now when try below code it gives a white screen. This is my first time using Google maps for IOS, please help me out.

Restaurant *res = [[Restaurant alloc] init];

for (res in _restaurantData) {
    GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude: [res.objectLocation.lat doubleValue]
                                                            longitude: [res.objectLocation.lng doubleValue] zoom: 5];

    GMSMapView *mapView = [GMSMapView mapWithFrame:CGRectZero camera:camera];

    GMSMarker *marker = [ [GMSMarker alloc] init];
    marker.position = CLLocationCoordinate2DMake([res.objectLocation.lat doubleValue], [res.objectLocation.lng doubleValue]);
    marker.appearAnimation = kGMSMarkerAnimationPop;
    marker.icon = [UIImage imageNamed:@"fork_filled"];
    marker.map = mapView;
}

Answer 1

Your loop must be like

for (Restaurant *res in _restaurantData) {
    GMSMarker *marker = [ [GMSMarker alloc] init];
    marker.position = CLLocationCoordinate2DMake([res.objectLocation.lat doubleValue], [res.objectLocation.lng doubleValue]);
    marker.appearAnimation = kGMSMarkerAnimationPop;
    marker.icon = [UIImage imageNamed:@"fork_filled"];
    marker.map = mapView;
}