title: CLPlacemark multiple places
body: <p>i use below code to search places on map but every time i search a new pin added to the map, i want when i search a place ,remove previous pin and add new pin</p>
  
  <pre><code>-(void)searchBarSearchButtonClicked:(UISearchBar *)searchBar{
  [self.searchMap resignFirstResponder];
  
  //inistantiate geoLocation
  CLGeocoder *geocoder=[[CLGeocoder alloc]init];
  [geocoder geocodeAddressString:self.searchMap.text completionHandler:^(NSArray *placemarks, NSError *error) {
  
      //Mark location and center
      CLPlacemark *placemark=[placemarks lastObject];
      if(placemark){
      MKCoordinateRegion region;
  
      CLLocationCoordinate2D newlocation=[placemark.location coordinate];
      region.center=[(CLCircularRegion *)placemark.region center];
  
      // Drop pin
  
  
      NSString *address=[NSString stringWithFormat:@"%@", ABCreateStringWithAddressDictionary(placemark.addressDictionary, NO)];
      MKPointAnnotation *annotation=[[MKPointAnnotation alloc]init];
      [annotation setCoordinate:newlocation];
      [annotation setTitle:address];
      [self.mapview addAnnotation:annotation];
  
      //scroll to search result
      MKMapRect mr=[self.mapview visibleMapRect];
      MKMapPoint pt=MKMapPointForCoordinate([annotation coordinate]);
      mr.origin.x=pt.x-mr.size.width*0.5;
      mr.origin.y=pt.y-mr.size.height*0.5;
      [self.mapview setVisibleMapRect:mr animated:YES];
  
      aLng=newlocation.longitude;
      aLat=newlocation.longitude;
          searchMap.text=address;}
  }];
  }
  </code></pre>