我正在开发一个应用程序，我想在地图中显示我当前的位置，它显示但如果我更改位置显示以前的位置请告诉我我的代码错误
我的代码
public class GetLatLongForTPActivity extends FragmentActivity implements LocationListener{
GoogleMap _googleMap;
static final LatLng SEC = new LatLng(17.433189,78.502223);
static final LatLng Safilguda = new LatLng(17.464166,78.536156);
static final LatLng Fathe = new LatLng(17.455932,78.450132);
LatLng myPosition;
LatLongDetails latLongDetails = new LatLongDetails();;
private EditText timeEdit;
private Button submitBtn;
private Button cancelBtn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_get_lat_long_for_tp);
timeEdit = (EditText)findViewById(R.id.timeId);
submitBtn = (Button)findViewById(R.id.subId);
/*Intent intent = getIntent();
String anotherLAT=intent.getStringExtra("LAT");
String anotherLNG=intent.getStringExtra("LNG");
*/
ArrayList<HashMap<String, String>> arl = (ArrayList<HashMap<String, String>>)
getIntent().getSerializableExtra("arrayList");
Log.e(" NEW LATLONG1",arl.get(0).toString());
Log.e(" NEW LATLONG2",arl.get(1).toString());
Log.e(" NEW LATLONG3",arl.get(2).toString());
_googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(
R.id.map)).getMap();
if(_googleMap==null){
Toast.makeText(getApplicationContext(), "Google Map Not Available", Toast.LENGTH_LONG).show();
}
LocationManager locationManger = (LocationManager)getSystemService(LOCATION_SERVICE);
Criteria criteria=new Criteria();
Marker perth = _googleMap.addMarker(new MarkerOptions()
.position(SEC)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE))
.flat(true));
/*Marker Safilg = _googleMap.addMarker(new MarkerOptions()
.position(Safilguda)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE))
.flat(true));
Marker Saf = _googleMap.addMarker(new MarkerOptions()
.position(Fathe)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE))
.flat(true));*/
String provider = locationManger.getBestProvider(criteria, true);
Location location = locationManger.getLastKnownLocation(provider);
if(location!=null){
double latitude = location.getLatitude();
double langitude = location.getLongitude();
latLongDetails.setLat(latitude);
latLongDetails.setLongi(langitude);
Log.e("lat",""+ latLongDetails.getLat());
Log.e("long", ""+latLongDetails.getLongi());
LatLng latlang = new LatLng(latitude, langitude);
LatLngBounds curScreen = _googleMap.getProjection().getVisibleRegion().latLngBounds;
curScreen.contains(latlang);
myPosition = new LatLng(latitude, langitude);
_googleMap.moveCamera(CameraUpdateFactory.newLatLng(myPosition));
_googleMap.addMarker(new MarkerOptions().position(myPosition).title("start"));
//_googleMap.setOnMarkerClickListener(GetLatLongForTPActivity.this);
submitBtn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
String
clreatime=timeEdit.getText().toString().trim();
latLongDetails.setClearTime(clreatime);
Log.e("time",
latLongDetails.getClearTime());
new
SendLatLongValAsync(GetLatLongForTPActivity.this).execute(latLongDetails);
}
});
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
//getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
答案 0 :(得分：2)
设置您的Activity，如下所示：
public class BasicMapActivity_new extends FragmentActivity implements LocationListener {
private GoogleMap mMap;
private LocationManager locationManager;
private String provider;
Double Latitude,longitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.basic_demo);
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map2)).getMap();
mMap.setMyLocationEnabled(true);
LocationManager service = (LocationManager) getSystemService(LOCATION_SERVICE);
boolean enabledGPS = service
.isProviderEnabled(LocationManager.GPS_PROVIDER);
boolean enabledWiFi = service
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!enabledGPS) {
Toast.makeText(BasicMapActivity_new.this, "GPS signal not found", Toast.LENGTH_LONG).show();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
else if(!enabledWiFi){
Toast.makeText(BasicMapActivity_new.this, "Network signal not found", Toast.LENGTH_LONG).show();
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
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, false);
Location location = locationManager.getLastKnownLocation(provider);
// Initialize the location fields
if (location != null) {
onLocationChanged(location);
} else {
//do something
}
setUpMap();
}
@Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
@Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
setUpMapIfNeeded();
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map2))
.getMap();
mMap.setMyLocationEnabled(true);
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
private void setUpMap() {
mMap.getUiSettings().setCompassEnabled(true);
mMap.getUiSettings().setTiltGesturesEnabled(true);
mMap.getUiSettings().setRotateGesturesEnabled(true);
mMap.getUiSettings().setScrollGesturesEnabled(true);
mMap.getUiSettings().setZoomControlsEnabled(true);
mMap.getUiSettings().setZoomGesturesEnabled(true);
}
Marker startPerc=null;
Location old_one;
@Override
public void onLocationChanged(Location location) {
double lat = location.getLatitude();
double lng = location.getLongitude();
LatLng coordinate = new LatLng(lat, lng)
startPerc = mMap.addMarker(new MarkerOptions()
.position(coordinate)
.title("Current Location")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_BLUE)));
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 18.0f))
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
不要忘记在manifest.xml文件
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
答案 1 :(得分：1)
您在获取位置详细信息时使用了getLastKnownLocation()方法。此方法始终返回最后知道的坐标。因此，我建议您在代码中对此行Location location = locationManger.getLastKnownLocation(provider);进行评论。然后它会正常运行。
答案 2 :(得分：0)
要更新您的位置，您必须将位置监听器注册到位置管理员。并使用覆盖方法onLocationChanged（）来获取最新位置。 请参阅http://developer.android.com/guide/topics/location/strategies.html