如何使用谷歌地图计算用户的精确距离？

Question

我有两个疑惑，因为今天只有我开始在谷歌做项目地图中的第一个疑问是

1. 如何使用谷歌地图时，通过计算用户行进的距离？

像出租车应用程序是如何计算的距离，现在让我解释一下我的问题深入关于这个问题，我已经签入和地图退房按钮时，用户点击签入按钮，我将采取精确的纬度和长该用户在用户结帐时，我将取出经纬度，并从他检出的地方开始，在我将此源latlong和目标latlong发送到google api后，这将返回公里。但是，我需要的是他旅行的任何地方，他可能会走多余的公里我需要计算，我怎么能做到这一点。

1. 我的第二个疑问是我的Google地图需要很长时间来绘制我的地图中的蓝色标记，它显示在通知栏中搜索gps我如何实现这一目标？

下面是我完整的代码

VisitTravel.java

public class VisitTravel extends FragmentActivity implements OnMapReadyCallback, 
GoogleApiClient.ConnectionCallbacks, 
    GoogleApiClient.OnConnectionFailedListener, 
    LocationListener { 
    private List <LatLng> obj; 
    private GoogleMap mGoogleMap; 
    private Double latitue, longtitue, Start_lat, Start_long; 
    private SupportMapFragment mapFrag; 
    private LocationRequest mLocationRequest; 
    private GoogleApiClient mGoogleApiClient; 
    private Location mLastLocation; 
    private ImageView cancel_bottomsheet; 
    protected static final int REQUEST_CHECK_SETTINGS = 0x1; 

    private Bundle bundle; 
    private ProgressDialog progressDialog; 
    private String Checkin, parsedDistance, duration, JsonResponse; 
    private VisitDAO visitDAO; 
    private Long primaryID; 
    private ArrayList <LatLng> points; 
    private Integer id, flag, incidentid, userid; 
    private TextView heading, duration_textview, dot_source, destination, distance; 
    private PowerManager.WakeLock wakeLock; 
    private BottomSheetBehavior bottomSheetBehavior; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_visit_travel); 
     // Obtain the SupportMapFragment and get notified when the map is ready to be used. 
     mapFrag = (SupportMapFragment) getSupportFragmentManager() 
     .findFragmentById(R.id.map); 
     mapFrag.getMapAsync(this); 
     InternetCheck internetCheck = new InternetCheck(); 
     boolean check = internetCheck.isNetworkAvailable(VisitTravel.this); 
     if (!check) { 
     showAlertDialog(); 
     } else { 
     createLocationRequest(); 
     buildGoogleApiClient(); 
     Settingsapi(); 
     progressDialog = new ProgressDialog(VisitTravel.this); 
     // polylineOptions = new PolylineOptions(); 
     cancel_bottomsheet = (ImageView) findViewById(R.id.cancel); 
     heading = (TextView) findViewById(R.id.heading); 
     dot_source = (TextView) findViewById(R.id.dot_source); 
     distance = (TextView) findViewById(R.id.distance); 
     duration_textview = (TextView) findViewById(R.id.duration); 
     destination = (TextView) findViewById(R.id.destination); 
     progressDialog.setMessage("Fetching Location Updates"); 
     progressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER); 
     progressDialog.show(); 
     View bottomSheet = findViewById(R.id.bottom_sheet); 
     LoginDAO loginobj = new LoginDAO(this); 
     userid = loginobj.getUserID(); 
     bottomSheetBehavior = BottomSheetBehavior.from(bottomSheet); 
     bottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN); 
     cancel_bottomsheet.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
      bottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN); 
      } 
     }); 
     bundle = getIntent().getExtras(); 
     if (bundle != null) { 
      flag = bundle.getInt("flag"); 
      latitue = bundle.getDouble("destination_lat"); 
      longtitue = bundle.getDouble("destination_long"); 
      incidentid = bundle.getInt("incidentid"); 
      if (flag == 1) { 

      } else { 
      // time = bundle.getString("checkin"); 
      id = bundle.getInt("id"); 
      incidentid = bundle.getInt("incidentid"); 
      Start_lat = bundle.getDouble("lat"); 
      Checkin = bundle.getString("checkin"); 
      Start_long = bundle.getDouble("long"); 
      String address = bundle.getString("startaddress"); 
      String distance = bundle.getString("estimateddistance"); 
      setBottomSheet(address, distance); 
      } 
     } 
     obj = new ArrayList < >(); 
     final FloatingActionButton startfab = (FloatingActionButton) findViewById(R.id.start); 
     final FloatingActionButton stopfab = (FloatingActionButton) findViewById(R.id.stopfab); 
     PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE); 
     wakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, 
      "WakelockTag"); 
     wakeLock.acquire(); 
     visitDAO = new VisitDAO(getApplicationContext()); 
     if (flag == 2) { 
      startfab.setVisibility(View.INVISIBLE); 
     } 
     startfab.setBackgroundResource(R.drawable.ic_play_circle_outline_black_24dp); 
     final SharedPreferences preferences = getSharedPreferences("lat_long", Context.MODE_PRIVATE); 
     startfab.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       if (mLastLocation != null) { 
       String checkin_to_server = dateFormat.format(new Date()); 
       Date date = null; 
       try { 
        date = dateFormat.parse(checkin_to_server); 
       } catch (ParseException e) { 
        e.printStackTrace(); 
       } 

       String checkin_view = dateview.format(date); 
       double startinglat = mLastLocation.getLatitude(); 
       double startinglong = mLastLocation.getLongitude(); 
       //  String addres=address(startinglat,startinglong); 
       String jsonresponse = null; 
       try { 
        jsonresponse = new GetDistance().execute(startinglat, startinglong, 12.951601, 80.184641).get(); 
       } catch (InterruptedException e) { 
        e.printStackTrace(); 
       } catch (ExecutionException e) { 
        e.printStackTrace(); 
       } 
       ParserTask parserTask = new ParserTask(); 
       if (jsonresponse != null) { 
        Log.d("responsejson", jsonresponse); 
        parserTask.execute(jsonresponse); 
       } 
       JSONObject jsonObject = null; 
       try { 
        jsonObject = new JSONObject(jsonresponse); 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 

       //Here il save the userlocation in db 
       } catch (JSONException e) { 
       e.printStackTrace(); 
       } 
      } else { 
       Toast.makeText(getApplicationContext(), "Please Wait Till We Recieve Location Updates", Toast.LENGTH_SHORT).show(); 

      } 

      } 
     }); 
     stopfab.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      if (mLastLocation != null) { 
      double lat = mLastLocation.getLatitude(); 
      double longt = mLastLocation.getLongitude(); 
      String startlat = preferences.getString("startlat", ""); 
      Log.d("startlat", startlat); 
      String startlong = preferences.getString("startlong", ""); 
      // Calculating distance 
      String distance = getKilometer(Double.valueOf(startlat), Double.valueOf(startlong), lat, longt); 
      Intent intent = new Intent(VisitTravel.this, IncidentView.class); 
      setResult(RESULT_OK, intent); 
      finish(); 
      } else { 
      Toast.makeText(getApplicationContext(), "Please Wait Fetching Location", Toast.LENGTH_SHORT).show(); 
      } 
     } 
     }); 
    } 
    } 

@Override 
public void onStart() { 
    super.onStart(); 
    Log.d("start", "onStart fired .............."); 
    mGoogleApiClient.connect(); 
} 

private void showAlertDialog() { 
    AlertDialog.Builder builder = new AlertDialog.Builder(VisitTravel.this); 
    builder.setTitle("Network Connectivity") 
    .setMessage("Please Check Your Network Connectivity") 
    .setCancelable(false) 
    .setNegativeButton("Close", new DialogInterface.OnClickListener() { 
     public void onClick(DialogInterface dialog, int id) { 
     Intent intent = new Intent(getApplicationContext(), IncidentView.class); 
     setResult(RESULT_OK, intent); 
     finish(); 
     } 
    }); 
    AlertDialog alert = builder.create(); 
    alert.show(); 
} 

@Override 
public void onPause() { 
    super.onPause(); 
    // progressDialog.dismiss(); 
    if (wakeLock.isHeld()) { 
    wakeLock.release(); 
    } 
    //stop location updates when Activity is no longer active 
    if (mGoogleApiClient.isConnected()) { 
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this); 
    mGoogleApiClient.disconnect(); 
    } 
} 

@Override 
public void onMapReady(GoogleMap googleMap) { 
    mGoogleMap = googleMap; 
    mGoogleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL); 
    map_marker_End(12.951601, 80.184641, "Destination"); 
    if (flag == 2) { 
    map_marker_start(Start_lat, Start_long, Checkin); 
    } 
    //Initialize Google Play Services 
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { 
    if (ContextCompat.checkSelfPermission(this, 
     android.Manifest.permission.ACCESS_FINE_LOCATION) == 
     PackageManager.PERMISSION_GRANTED) { 
     //Location Permission already granted 
     createLocationRequest(); 
     buildGoogleApiClient(); 
     mGoogleMap.setMyLocationEnabled(true); 
    } else { 
     //Request Location Permission 
     checkLocationPermission(); 
    } 
    } else { 
    buildGoogleApiClient(); 
    mGoogleMap.setMyLocationEnabled(true); 
    } 

} 

protected synchronized void buildGoogleApiClient() { 

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

} 

protected void createLocationRequest() { 
    mLocationRequest = new LocationRequest(); 
    mLocationRequest.setInterval(1000 * 10); 
    mLocationRequest.setFastestInterval(1000 * 5); 
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY); 
} 

@Override 
public void onConnected(Bundle bundle) { 

    startLocationUpdates(); 
} 

protected void startLocationUpdates() { 
    if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
    // TODO: Consider calling 
    Toast.makeText(this, "LocationNotUpdated", Toast.LENGTH_SHORT).show(); 
    ActivityCompat.requestPermissions(VisitTravel.this, 
     new String[] { 
     android.Manifest.permission 
      .ACCESS_COARSE_LOCATION, Manifest.permission.ACCESS_FINE_LOCATION 
     }, 
     20); 

    } else { 
    if (mGoogleApiClient.isConnected()) { 
     LocationServices.FusedLocationApi.requestLocationUpdates(
     mGoogleApiClient, mLocationRequest, this); 
     Log.d("Loc", "Location update started ..............: "); 
     //  Toast.makeText(this, "LocationUpdatedStart", Toast.LENGTH_SHORT).show(); 
    } 
    } 
} 

@Override 
public void onConnectionSuspended(int i) {} 

@Override 
public void onConnectionFailed(ConnectionResult connectionResult) { 

} 


public void map_marker_start(Double lat, Double longt, String title) { 
    MarkerOptions markerOptions = new MarkerOptions(); 
    LatLng latLng = new LatLng(lat, longt); 
    Log.d("lat", String.valueOf(latLng.longitude)); 
    markerOptions.position(latLng); 
    markerOptions.title(title); 
    markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED)); 
    mGoogleMap.addMarker(markerOptions).showInfoWindow(); 

} 

public void map_marker_End(Double lat, Double longt, String title) { 
    final MarkerOptions markerOptions_end = new MarkerOptions(); 
    LatLng latLng = new LatLng(lat, longt); 
    Log.d("lat", String.valueOf(latLng.longitude)); 
    markerOptions_end.position(latLng); 
    markerOptions_end.title(title); 
    markerOptions_end.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN)); 
    mGoogleMap.addMarker(markerOptions_end).showInfoWindow(); 
    mGoogleMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() { 
    @Override 
    public boolean onMarkerClick(Marker marker) { 
     String title = marker.getTitle(); 
     if (title.equals("Destination")) { 
     dot_source.setText("\u2022"); 
     bottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED); 
     heading.setText("TEST"); 
     duration_textview.setText("Duration:" + " " + duration); 
     return true; 
     } else { 
     bottomSheetBehavior.setState(BottomSheetBehavior.STATE_HIDDEN); 
     return true; 

     } 

    } 
    }); 

} 

@Override 
public void onLocationChanged(Location location) { 
    mLastLocation = location; 
    PolylineOptions polylineOptions = new PolylineOptions(); 
    Log.d("location", mLastLocation.toString()); 
    LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude()); 
    obj.add(latLng); 
    polylineOptions.addAll(obj); 
    polylineOptions.width(9); 
    polylineOptions.color(Color.parseColor("#2196f3")); 
    mGoogleMap.addPolyline(polylineOptions); 
    progressDialog.dismiss(); 
    mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
    CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(
    latLng, 12); 
    mGoogleMap.animateCamera(cameraUpdate); 
} 

public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99; 

private void checkLocationPermission() { 
    if (ContextCompat.checkSelfPermission(VisitTravel.this, android.Manifest.permission.ACCESS_FINE_LOCATION) != 
    PackageManager.PERMISSION_GRANTED) { 

    // Should we show an explanation? 
    if (ActivityCompat.shouldShowRequestPermissionRationale(this, 
     android.Manifest.permission.ACCESS_FINE_LOCATION)) { 

     // Show an explanation to the user *asynchronously* -- don't block 
     // this thread waiting for the user's response! After the user 
     // sees the explanation, try again to request the permission. 
     new AlertDialog.Builder(this) 
     .setTitle("Location Permission Needed") 
     .setMessage("This app needs the Location permission, please accept to use location functionality") 
     .setPositiveButton("OK", new DialogInterface.OnClickListener() { 
      @Override 
      public void onClick(DialogInterface dialogInterface, int i) { 
      //Prompt the user once explanation has been shown 
      ActivityCompat.requestPermissions(VisitTravel.this, 
       new String[] { 
       android.Manifest.permission.ACCESS_FINE_LOCATION 
       }, 
       MY_PERMISSIONS_REQUEST_LOCATION); 
      } 
     }) 
     .create() 
     .show(); 


    } else { 
     // No explanation needed, we can request the permission. 
     ActivityCompat.requestPermissions(this, 
     new String[] { 
      android.Manifest.permission.ACCESS_FINE_LOCATION 
     }, 
     MY_PERMISSIONS_REQUEST_LOCATION); 
    } 
    } 
} 

@Override 
public void onRequestPermissionsResult(int requestCode, 
    String permissions[], int[] grantResults) { 
    switch (requestCode) { 
    case MY_PERMISSIONS_REQUEST_LOCATION: 
     { 
     // If request is cancelled, the result arrays are empty. 
     if (grantResults.length > 0 && 
      grantResults[0] == PackageManager.PERMISSION_GRANTED) { 

      // permission was granted, yay! Do the 
      // location-related task you need to do. 
      if (ContextCompat.checkSelfPermission(this, 
       android.Manifest.permission.ACCESS_FINE_LOCATION) == 
      PackageManager.PERMISSION_GRANTED) { 

      if (mGoogleApiClient == null) { 
       buildGoogleApiClient(); 
      } 
      createLocationRequest(); 
      /// buildGoogleApiClient(); 
      // Settingsapi(); 
      mGoogleMap.setMyLocationEnabled(true); 
      } 

     } else { 

      // permission denied, boo! Disable the 
      // functionality that depends on this permission. 
      Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show(); 
     } 
     return; 
     } 

     // other 'case' lines to check for other 
     // permissions this app might request 
    } 
} 



public String getKilometer(final double lat1, final double lon1, final double lat2, final double lon2) { 
    Thread thread = new Thread(new Runnable() { 
    @Override 
    public void run() { 
     try { 
     URL url = new URL("http://maps.googleapis.com/maps/api/directions/json?origin=" + lat1 + "," + lon1 + "&destination=" + lat2 + "," + lon2 + "&sensor=false&units=metric&mode=driving"); 
     final HttpURLConnection conn = (HttpURLConnection) url.openConnection(); 
     conn.setRequestMethod("POST"); 
     InputStream in = new BufferedInputStream(conn.getInputStream()); 
     StringBuilder buffer = new StringBuilder(); 
     BufferedReader reader = null; 
     reader = new BufferedReader(new InputStreamReader(in)); 
     String inputLine; 
     while ((inputLine = reader.readLine()) != null) 
      buffer.append(inputLine + "\n"); 
     if (buffer.length() == 0) { 
      // Stream was empty. No point in parsing. 
      Log.e("empty", "empty"); 
     } 
     JsonResponse = buffer.toString(); 
     Log.d("response", JsonResponse); 
     JSONObject jsonObject = new JSONObject(JsonResponse); 
     JSONArray array = jsonObject.getJSONArray("routes"); 
     JSONObject routes = array.getJSONObject(0); 
     JSONArray legs = routes.getJSONArray("legs"); 
     JSONObject steps = legs.getJSONObject(0); 
     JSONObject distance = steps.getJSONObject("distance"); 
     parsedDistance = distance.getString("text"); 


     } catch (ProtocolException e) { 
     e.printStackTrace(); 
     } catch (MalformedURLException e) { 
     e.printStackTrace(); 
     } catch (IOException e) { 
     e.printStackTrace(); 
     } catch (JSONException e) { 
     e.printStackTrace(); 
     } 
    } 
    }); 
    thread.start(); 
    try { 
    thread.join(); 
    } catch (InterruptedException e) { 
    e.printStackTrace(); 
    } 
    return parsedDistance; 
} 



@Override 
protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
    switch (requestCode) { 
    // Check for the integer request code originally supplied to startResolutionForResult(). 
    case REQUEST_CHECK_SETTINGS: 
     switch (resultCode) { 
     case Activity.RESULT_OK: 
      startLocationUpdates(); 
      break; 
     case Activity.RESULT_CANCELED: 
      Intent intent = new Intent(this, Incident.class); 
      startActivity(intent); 
      break; 
     } 
     break; 
    } 
} 


@Override 
protected void onStop() { 
    super.onStop(); 
    if (wakeLock.isHeld()) { 
    wakeLock.release(); 
    } 

} 




@Override 
public void onBackPressed() { 
    super.onBackPressed(); 
    Intent intent = new Intent(this, IncidentView.class); 
    if (mGoogleApiClient.isConnected()) { 
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this); 
    mGoogleApiClient.disconnect(); 
    } 
    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK); 
    setResult(RESULT_OK, intent); 
    finish(); 
} 
} 

搜查了很多，没有得到适当的方式开始吗？任何帮助都很有价值。

- 谢谢！

Answer 1

这工作对我来说：

定期捕获经度和纬度，并存储。计算并累加每个存储值之间的距离。