在Google Maps HTML中简单添加kml层

Question

My first question regarding google maps API. What this code does is that it directs us to a location on a map. The problem is I'm trying to add google objects like polylines to it but I can't see them on the webpage.

1.Why I can't see the polyline drawn?

How to add 1. polylines 2.kml layers 3.xml data from separate file into the button from the code below.

    <!--
        var mapa;       // obiekt globalny
        var dymek;      // okno z informacjami
        var geokoder    = new google.maps.Geocoder();

        var rozmiar             = new google.maps.Size(32,32);
        var rozmiar_cien        = new google.maps.Size(59,32);
        var punkt_startowy      = new google.maps.Point(0,0);
        var punkt_zaczepienia   = new google.maps.Point(16,16);
        var ikona               = new google.maps.MarkerImage("http://maps.google.com/mapfiles/kml/pal3/icon52.png", rozmiar, punkt_startowy, punkt_zaczepienia);
        var cien                = new google.maps.MarkerImage("http://maps.google.com/mapfiles/kml/pal3/icon52s.png", rozmiar_cien, punkt_startowy, punkt_zaczepienia);
        var wskaznik            = new google.maps.Marker({icon: ikona, shadow: cien});

        function mapaStart()
        {
            var wspolrzedne = new google.maps.LatLng(37.7671, -122.4206);
            var opcjeMapy = {
                zoom: 15,
                center: wspolrzedne,
                mapTypeId: google.maps.MapTypeId.ROADMAP,
                disableDefaultUI: true
            };
            mapa = new google.maps.Map(document.getElementById("mapka"), opcjeMapy);
            dymek = new google.maps.InfoWindow();

            // Creating an array that will contain the points for the polyline 
            var route = [     
                new google.maps.LatLng(37.7671, -122.4206),       
                new google.maps.LatLng(34.0485, -118.2568)    
            ];          // Creating the polyline object 

            var polyline = new google.maps.Polyline({
                path: route, strokeColor: "#ff0000",
                strokeOpacity: 0.6,      
                strokeWeight: 5     });        
            // Adding the polyline to the map 
            polyline.setMap(map);      



            geokoder.geocode({address: 'Szczecin, Krzywoustego 23'}, obslugaGeokodowania);



        }


        function skoczDoAdresu(adres)
        {
            wskaznik.setMap(null);
            geokoder.geocode({address: adres}, function(wyniki, status)
            {
                if(status == google.maps.GeocoderStatus.OK)
                {
                    mapa.setCenter(wyniki[0].geometry.location);
                    wskaznik.setPosition(wyniki[0].geometry.location);
                    wskaznik.setMap(mapa);
                    dymek.open(mapa, wskaznik);
                    dymek.setContent('<strong>Poszukiwany adres</strong><br />'+adres);
                }
                else
                {
                    alert("Nie znalazłem podanego adresu!");
                }
            });
        }

        function obslugaGeokodowania(wyniki, status)
        {

        }

    -->
</script>

Answer 1

You can't see the polyline because "map" is not defined in this line:

// Adding the polyline to the map 
polyline.setMap(map);    

Your javascript console should tell you that, the google.maps.Map object is called "mapa"