如何顯示棉花糖的經度和緯度？

Question

我正在應用程序中以列表的形式顯示數據。當用戶點擊列表項時，會顯示特定列表項的詳細信息。直到現在我能夠顯示我的應用程序中的所有數據。但我在谷歌地圖中遇到問題，我必須顯示位置。當我的應用程序第一次啓動時，我可以看到地圖中的位置（Image），但是當我的應用程序第二次啓動時，我無法看到地圖中的位置（Image）。我完全陷入了這種困境，我沒有明白我做錯了什麼。請指導我解決這個問題。

的onCreate

mFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map); 
mFragment.getMapAsync(this); 

mGoogleApiClient = new GoogleApiClient.Builder(this) 
     .addApi(LocationServices.API) 
     .addConnectionCallbacks(this) 
     .addOnConnectionFailedListener(this) 
     .build(); 
mGoogleApiClient.connect(); 

mLocationRequest = new LocationRequest(); 
mLocationRequest.setInterval(5000); //5 seconds 
mLocationRequest.setFastestInterval(3000); //3 seconds 
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY); 

我這樣做是爲了在地圖上顯示的位置

@Override 
protected void onStart() { 
    super.onStart(); 
    mGoogleApiClient.connect(); 
} 

@Override 
protected void onResume() { 
    super.onResume(); 
    if(mGoogleApiClient.isConnected()){ 
     requestLocationUpdates(); 
    } 
} 

@Override 
protected void onStop() { 
    super.onStop(); 
    mGoogleApiClient.disconnect(); 
} 



@Override 
public void onMapReady(GoogleMap googleMap) { 




    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { 

      mGoogleMap = googleMap; 

      LatLng latlng = new LatLng(lat, lon); 
      mGoogleMap.addMarker(new MarkerOptions().position(latlng).title("Marker")); 
      mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(latlng)); 


    } else { 
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { 
      requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSION_FINE_LOCATION); 
     } 
    } 

} 

@Override 
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { 
    super.onRequestPermissionsResult(requestCode, permissions, grantResults); 
    switch (requestCode) { 
     case MY_PERMISSION_FINE_LOCATION: 
      if (grantResults[0] == PackageManager.PERMISSION_GRANTED) { 
       if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { 

        requestLocationUpdates(); 

       } 
      } else { 
       Toast.makeText(Property_Detail.this, "App Require Permission", Toast.LENGTH_SHORT).show(); 
       finish(); 
      } 

      break; 
    } 

} 


@Override 
public void onConnected(Bundle bundle) { 
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { 


    requestLocationUpdates(); 

    } 

} 

@Override 
public void onConnectionSuspended(int i) { 
    Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show(); 
} 
@Override 
public void onConnectionFailed(ConnectionResult connectionResult) { 
    Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show(); 
} 

private void requestLocationUpdates() { 

    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { 

     mGoogleMap.clear(); 
     latLng = new LatLng(lat, lon); 
     MarkerOptions markerOptions = new MarkerOptions(); 
     markerOptions.position(latLng); 
     markerOptions.title("Position"); 
     markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN)); 
     mCurrLocation = mGoogleMap.addMarker(markerOptions); 
    } 

} 


@Override 
public void onLocationChanged(Location location) { 


    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { 
     myLatitude = lat; 
     myLongitude = lon; 

    } 

} 

Answer 1

的地方在地圖上你的新經緯度撥打以上日誌或吐司準備和使用調試器時看到地圖所謂的位置的價值是什麼，我認爲你沒有加載地圖，每當你需要或刷新，有一種方法稱爲

打電話給你，只要你需要relo廣告

my_map_fragment.getMapAsync(this);