如何獲取當前在谷歌地圖上的位置在android

Question

在這個我的代碼我不明白我在我的代碼中犯了什麼錯誤。我沒有得到具有針點圖像的地圖視圖上的當前位置。如何獲取緯度並通過地理點。然後傳遞價值OverlayItem ..

public class HelloGoogleMaps2 extends MapActivity implements LocationListener{ 

private LocationManager locationManager; 
private String provider; 
int lat; 
int lng; 
MyLocationOverlay myLocOverlay; 
@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.main); 

    MapView mapView = (MapView) findViewById(R.id.mapview);  
    mapView.setBuiltInZoomControls(true); 

    // Get the location manager 
    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
    // Define the criteria how to select the locatioin provider -> use 
    // default 
    Criteria criteria = new Criteria(); 
    provider = locationManager.getBestProvider(criteria, true); 
    Location location = locationManager.getLastKnownLocation(provider); 

    Log.d("provider ","Provider "+provider); 
    Log.d("provider ","Provider "+provider); 
    Log.d("provider ","Provider "+provider); 
    Log.d("location","Location "+location); 

    Log.d("location","Location "+location);   

    Log.d("location","Location "+location); 
    // Initialize the location fields 
    if (location != null) { 
     System.out.println("Provider " + provider + " has been selected."); 
     onLocationChanged(location); 
    } else { 
     //latituteField.setText("Location not available"); 
    // longitudeField.setText("Location not available"); 
    } 


    List<Overlay> mapOverlays = mapView.getOverlays(); 

    myLocOverlay = new MyLocationOverlay(this, mapView); 
    mapOverlays.add(myLocOverlay); 
    myLocOverlay.enableMyLocation(); 
    GeoPoint point = new GeoPoint(lat, lng); 
    //  mc.setCenter(point); 
    //  mapView.invalidate(); 

    Drawable drawable = this.getResources().getDrawable(R.drawable.ic_launcher); 
    HelloItemizedOverlay itemizedoverlay = new HelloItemizedOverlay(drawable); 

     GeoPoint point = new GeoPoint(lat,lng); 
OverlayItem overlayitem = new OverlayItem(point, "Hola, Mundo!", "I'm in Mexico City!"); 


itemizedoverlay.addOverlay(overlayitem); 
mapOverlays.add(itemizedoverlay); 
} 


@Override 
protected boolean isRouteDisplayed() { 
    // TODO Auto-generated method stub 
    return false; 
} 

protected void onResume() { 
     super.onResume(); 
     locationManager.requestLocationUpdates(provider, 400, 1, this); 
     } 

     /* Remove the locationlistener updates when Activity is paused */ 
     // 
     protected void onPause() { 
     super.onPause(); 
     locationManager.removeUpdates(this); 
     } 

     // 
     public void onLocationChanged(Location location) { 
     lat = (int) (location.getLatitude()* 1E6); 
     lng = (int) (location.getLongitude()* 1E6); 
     // latituteField.setText(String.valueOf(lat)); 
     // longitudeField.setText(String.valueOf(lng)); 
     } 

     // 
     public void onStatusChanged(String provider, int status, Bundle extras) { 
     // TODO Auto-generated method stub 

     } 

     // 
     public void onProviderEnabled(String provider) { 
     Toast.makeText(this, "Enabled new provider " + provider, 
      Toast.LENGTH_SHORT).show(); 

     } 

     // 
     public void onProviderDisabled(String provider) { 
     Toast.makeText(this, "Disabled provider " + provider, 
      Toast.LENGTH_SHORT).show(); 
     } 

}

Answer 1

參考這個鏈接，並按照它將同樣的步驟給出了結果：googlemaps for current location

Answer 2

我會建議MyLocationOverlay。

疊印在地圖上繪製用戶的當前位置（和精度），和/或一個羅盤玫瑰插圖。子語句可以覆蓋dispatchTap（）來處理當前位置上的點擊。
你會想從你的活動的Activity.onResume（）方法調用enableMyLocation（）和/或enableCompass（），很可能使這個疊加的特點。請記住在您的Activity的Activity.onPause（）方法中調用相應的disableMyLocation（）和/或disableCompass（）以在後臺關閉更新。
（可選）構造函數還可以使用MapController並通過在地圖偏離時平移地圖來顯示「我的位置」點，並在位置或方向發生更改時通過View來查看View.postInvalidate（）。
runnables可以在runOnFirstFix（java.lang.Runnable）中提供，以便在我們修復後立即運行。 （例如，這可能會在地圖中心，並放大顯示的位置）

你可以找到MyLocationOverlay一個很好的教程here

Answer 3

正確的代碼是這樣的，但也添加uses-permissio，Internet，ACCESS_COARSE_LOCATION，ACCESS_FINE_LOCATION和WRITE_EXTERNAL_STORAGE .user-library。

public class GoogleMapActivity extends MapActivity implements LocationListener { 
    private final static String TAG = GoogleMapActivity.class.getSimpleName(); 
private MyItemizedOverlay itemizedOverlay; 

double lat; 
double lng; 
private String provider; 
private LocationManager locationManager; 

private MapView mapview; 

Drawable drawable; 



boolean sat = true; 
boolean dra = true; 

private MapController controller; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    // fetch the map view from the layout 
    mapview = (MapView) findViewById(R.id.mapview); 

    // make available zoom controls 
    mapview.setBuiltInZoomControls(false); 

    // Use the location manager through GPS 

    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
    Criteria criteria = new Criteria(); 
    provider = locationManager.getBestProvider(criteria, false); 
    Location location = locationManager.getLastKnownLocation(provider); 

    if (location != null) { 
     System.out.println("Provider " + provider + " has been selected."); 
     lat = (double) (location.getLatitude()); 
     lng = (double) (location.getLongitude()); 

     Log.i(TAG, "Lattitude:" + lat); 
     Log.i(TAG, "Longitude:" + lng); 
     Toast.makeText(
       this, 
       "Current location:\nLatitude: " + lat + "\n" 
         + "Longitude: " + lng, Toast.LENGTH_LONG).show(); 
     // create geo point 
     GeoPoint point = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6)); 

     // get the MapController object 
     controller = mapview.getController(); 

     // animate to the desired point 
     controller.animateTo(point); 

     // set the map zoom to 13 
     // zoom 1 is top world view 
     controller.setZoom(13); 

     // invalidate the map in order to show changes 
     mapview.invalidate(); 

     drawable = this.getResources().getDrawable(R.drawable.ic_launcher); 
     OverlayItem overlayItem = new OverlayItem(point, "", ""); 
     itemizedOverlay = new MyItemizedOverlay(drawable, this); 
     itemizedOverlay.addOverlay(overlayItem); 
     mapview.getOverlays().add(itemizedOverlay); 
     mapview.invalidate(); 
    } else { 

     System.out.println("Location not avilable"); 
    } 

    // when the current location is found – stop listening for updates 
    // (preserves battery) 
    locationManager.removeUpdates(this); 

} 

@Override 
protected boolean isRouteDisplayed() { 
    return false; 

} 

@Override 
protected void onResume() { 
    super.onResume(); 
    locationManager.requestLocationUpdates(provider, 400, 1, this); 
} 

/* Remove the locationlistener updates when Activity is paused */ 
@Override 
protected void onPause() { 
    super.onPause(); 
    locationManager.removeUpdates(this); 
} 

public void onProviderDisabled(String provider) { 
    Toast.makeText(this, "Disabled provider " + provider, 
      Toast.LENGTH_SHORT).show(); 
} 

public void onProviderEnabled(String provider) { 
    Toast.makeText(this, "Enabled new provider " + provider, 
      Toast.LENGTH_SHORT).show(); 
} 

public void onStatusChanged(String provider, int status, Bundle extras) { 

} 

public void onLocationChanged(Location location) { 

} 

public MapView getMapView() { 
    return this.mapview; 
} 


    } 

'//這裏是另一個項目覆蓋的

public class MyItemizedOverlay extends ItemizedOverlay<OverlayItem> 
    { 



    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>(); 


    public MyItemizedOverlay(Drawable defaultMarker, Context ctx){ 
     super(boundCenterBottom(defaultMarker)); 

    } 

    public void addOverlay(OverlayItem overlay) { 
     mOverlays.add(overlay); 
     populate(); 
    } 

    public void clear() { 
     mOverlays.clear(); 
     populate(); 
    } 

    @Override 
    protected OverlayItem createItem(int i) { 
     return mOverlays.get(i); 
    } 

    @Override 
    public int size() { 
     return mOverlays.size(); 
    } 

    @Override 
    protected boolean onTap(int index) { 
     return true; 
    } 

}