Question

I am using google api V3 in my iOS App,
I requested to google api direction service, by http GET method, I got a very large json response, I got many alternate routes from origin to destination, now I want to show the route of each alternative on map, how should I done this ? is there any need to integrate google sdk in iOS, or can i use webView only, please help me, and suggest the simplest way.
Thanks in advance

Answer 1

you do not need to include any google SDK to draw the route over map. Look at the following classes.

MKPolyline

MKPolyLineview

The google map api Direction service will give you the legs(coordinates) to draw the route between two specific points.

As you already have the json response from the Direction api now you have to parse the json and get all the legs point from the json to create Coordinate array.

Jsonkit for parsing

These points may be or mostly encripted. How to decode the Google Directions API polylines field into lat long points in objective-C for iPhone?

If you have the coordinates array then first you have to create a CLLocationCoordinate2D array like following:

CLLocationCoordinate2D *pointArr        =       malloc(sizeof(CLLocationCoordinate2D) * [your_CoordinateArray count]);

for(int i = 0; i < [your_CoordinateArray count]; i++){
  pointArr[i]       =      [your_CoordinateArray objectAtIndex:i];
}

Then you have to add the polyline to your map

 MKPolyline *line                        = [MKPolyline polylineWithCoordinates:pointArr count:[your_CoordinateArray count]];

    if (nil != line)
    {
        [your_Map addOverlay:line];

    }

Then you have to implement the following map delegate:

- (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay
{       

MKOverlayView* overlayView = nil;

lineView                    =       [[MKPolylineView alloc] initWithPolyline:overlay];// lineView is an ivar, object of MKPolylineView
lineView.fillColor          =       [UIColor greenColor];
lineView.strokeColor        =       [UIColor greenColor];

lineView.lineWidth          =       10.0;
lineView.alpha              =       0.9;
overlayView                 =       lineView;

return overlayView;
}    

Now, if you want to show two different routes between two points then you have to create two different array of coordinates and apply the above method for both Arrays

Hope this will help you.