Convert MKMapRect to CLRegion aka convert visible region of mapview to CLRegion

convert.m

- (CLLocationDistance)getDistanceFrom:(CLLocationCoordinate2D)start to:(CLLocationCoordinate2D)end
{
	CLLocation *startLoc = [[CLLocation alloc] initWithLatitude:start.latitude longitude:start.longitude];
	CLLocation *endLoc = [[CLLocation alloc] initWithLatitude:end.latitude longitude:end.longitude];
	CLLocationDistance retVal = [startLoc distanceFromLocation:endLoc];
	[startLoc release];
	[endLoc release];

	return retVal;
}

- (void) convert
{    
    MKMapRect mRect = self.mapview.visibleMapRect;
    MKMapPoint neMapPoint = MKMapPointMake(MKMapRectGetMaxX(mRect), mRect.origin.y);
    MKMapPoint swMapPoint = MKMapPointMake(mRect.origin.x, MKMapRectGetMaxY(mRect));
    CLLocationCoordinate2D neCoord = MKCoordinateForMapPoint(neMapPoint);
    CLLocationCoordinate2D swCoord = MKCoordinateForMapPoint(swMapPoint);
    CLLocationDistance diameter = [self getDistanceFrom:neCoord to:swCoord];
    
    CLRegion *region = [[CLRegion alloc] initCircularRegionWithCenter: mapview_.centerCoordinate radius:(diameter/2) identifier:@"mapWindow"];
    
    //Now we can geocode an address inside the map's visible view...
    //CLGeocoder *geocoder = [[CLGeocoder alloc] init];
    //[geocoder geocodeAddressString:theSearchBar.text inRegion:region completionHandler:^(NSArray *placemarks, NSError *error) {}
}