Create MKMapView without adding to view

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I need to create a map, add an overlay to it and save it as image. I don't have any problem to do this BUT the thing is I need to do it without showing the map on screen. In fact, it must be done in a class that inherits from NSObject to be called from AppDelegate

I'm creating a map like this:

//Create map
    self.mapView = MKMapView(frame: CGRectMake(0.0, 0.0, 260.0, 260.0))
    self.mapView.delegate = self

And after doing overlay stuff (creating a route) I'm trying to get the image like this:

dispatch_async(dispatch_get_main_queue())
                {
                    self.mapView.addOverlay(route!)
                    self.mapView.setVisibleMapRect(boundingRegion!, animated: false)

                    UIGraphicsBeginImageContext(self.mapView.bounds.size);
                    self.mapView.layer.renderInContext(UIGraphicsGetCurrentContext())
                    var mapImage = UIGraphicsGetImageFromCurrentImageContext()

                    if mapImage != nil
                    {
                        var data = UIImageJPEGRepresentation(mapImage,0.8)
                        //Continue saving data to documents folder

But I always get an empty image with the "Legal" text. I suppose the problem is that the map is never really rendered on a view and therefore the current context is empty. Is even possible to create a map like this and create the resulting image? Is there any way to specify a valid "context" to do this job?

Thx

asked 1 min ago

rmvz3

138

Create MKMapView without adding to view