how can i getCurrent location and display also cit

问题:

i am new in android create current location and display its city name

i Have No idea About code so give some example to create current location and display also city name thnks in advance

回答1:

Use this code to get location name from latitude and longitude:

Geocoder geocoder;
        List<Address> addresses;
        geocoder = new Geocoder(context, Locale.getDefault());
            try {
                addresses = geocoder.getFromLocation(lat, lng, 1);
                if(addresses.size()>0)
                {
                String cityName = addresses.get(0).getAddressLine(0);
                 String stateName = addresses.get(0).getAddressLine(1);
                 //Toast.makeText(getApplicationContext(),stateName , 1).show();
                 String countryName = addresses.get(0).getAddressLine(2);
                 }
            }catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

for getting latitude and longitude of current location use following steps:

• Create new class in your project name it GPSTracker.java

• copy and paste code below into it

  public class GPSTracker extends Service implements LocationListener {

  private final Context mContext;
  
  // flag for GPS status
  boolean isGPSEnabled = false;
  
  // flag for network status
  boolean isNetworkEnabled = false;
  
  // flag for GPS status
  boolean canGetLocation = false;
  
   Location location; // location
    double latitude=0;// latitude
     double longitude=0; // longitude
  
  // The minimum distance to change Updates in meters
  private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
  
  // The minimum time between updates in milliseconds
  private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
  
  // Declaring a Location Manager
  protected LocationManager locationManager;
  
  public GPSTracker(Context context) {
      this.mContext = context;
      getLocation();
  }
  
  public Location getLocation() {
      try {
          locationManager = (LocationManager) mContext
                  .getSystemService(LOCATION_SERVICE);
  
          // getting GPS status
          isGPSEnabled = locationManager
                  .isProviderEnabled(LocationManager.GPS_PROVIDER);
  
          // getting network status
          isNetworkEnabled = locationManager
                  .isProviderEnabled(LocationManager.NETWORK_PROVIDER);
  
          if (!isGPSEnabled && !isNetworkEnabled) {
              // no network provider is enabled
          } else {
              this.canGetLocation = true;
              // First get location from Network Provider
              if (isNetworkEnabled) {
                  locationManager.requestLocationUpdates(
                          LocationManager.NETWORK_PROVIDER,
                          MIN_TIME_BW_UPDATES,
                          MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                  Log.d("Network", "Network");
                  if (locationManager != null) {
                      location = locationManager
                              .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                      Log.v("location ",""+location);
  
  
                      if (location != null) {
                          latitude = location.getLatitude();
                          longitude = location.getLongitude();
                      }
                  }
              }
              // if GPS Enabled get lat/long using GPS Services
              if (isGPSEnabled) {
                  if (location == null) {
                      locationManager.requestLocationUpdates(
                              LocationManager.GPS_PROVIDER,
                              MIN_TIME_BW_UPDATES,
                              MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                      Log.d("GPS Enabled", "GPS Enabled");
                      if (locationManager != null) {
                          location = locationManager
                                  .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                          Log.v("location ",""+location);
  
  
                          if (location != null) {
                              latitude = location.getLatitude();
                              longitude = location.getLongitude();
                          }
                      }
                  }
              }
          }
  
      } catch (Exception e) {
          e.printStackTrace();
      }
  
      return location;
  }
  
  /**
   * Stop using GPS listener
   * Calling this function will stop using GPS in your app
   * */
  public void stopUsingGPS(){
      if(locationManager != null){
          locationManager.removeUpdates(GPSTracker.this);
      }      
  }
  
  /**
   * Function to get latitude
   * */
  public  double getLatitude(){
      if(location != null){
          latitude = location.getLatitude();
      }
  
      // return latitude
      return latitude;
  }
  
  /**
   * Function to get longitude
   * */
  public  double getLongitude(){
      if(location != null){
          longitude = location.getLongitude();
      }
  
      // return longitude
      return longitude;
  }
  
  /**
   * Function to check GPS/wifi enabled
   * @return boolean
   * */
  public boolean canGetLocation() {
      return this.canGetLocation;
  }
  

  @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

  }

  @Override public IBinder onBind(Intent arg0) { // TODO Auto-generated method stub return null; } }

• Now where you want to get latitude and longitude use this code:

  GPSTracker mTracker = new GPSTracker(MyActivity.this); double lat = mTracker.getLatitude(); double lng = mTracker.getLongitude();

回答2:

public class MainActivity extends FragmentActivity implements
GooglePlayServicesClient.ConnectionCallbacks,
GooglePlayServicesClient.OnConnectionFailedListener
{
   LocationClient mLocationClient;
private TextView addressLabel;
private TextView locationLabel;
private Button getLocationBtn;
private Button disconnectBtn;
private Button connectBtn;

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

  locationLabel = (TextView) findViewById(R.id.locationLabel);
  addressLabel = (TextView) findViewById(R.id.addressLabel);
  getLocationBtn = (Button) findViewById(R.id.getLocation);

  getLocationBtn.setOnClickListener(new View.OnClickListener() {
     public void onClick(View view) {
        displayCurrentLocation();
     }
  });
  disconnectBtn = (Button) findViewById(R.id.disconnect);  
  disconnectBtn.setOnClickListener(new View.OnClickListener() {
     public void onClick(View view) {
        mLocationClient.disconnect();
        locationLabel.setText("Got disconnected....");
     }
  });
  connectBtn = (Button) findViewById(R.id.connect);  
  connectBtn.setOnClickListener(new View.OnClickListener() {
     public void onClick(View view) {
        mLocationClient.connect();
        locationLabel.setText("Got connected....");
     }
  });   
  // Create the LocationRequest object
   mLocationClient = new LocationClient(this, this, this);  
 }  
 @Override
 protected void onStart() {
  super.onStart();
  // Connect the client.
  mLocationClient.connect();
  locationLabel.setText("Got connected....");
}
@Override
protected void onStop() {
  // Disconnect the client.
  mLocationClient.disconnect();
  super.onStop();
  locationLabel.setText("Got disconnected....");
  }
  @Override
  public void onConnected(Bundle dataBundle) {
  // Display the connection status
  Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show();
}
@Override
public void onDisconnected() {
  // Display the connection status
  Toast.makeText(this, "Disconnected. Please re-connect.",
  Toast.LENGTH_SHORT).show();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
  // Display the error code on failure
  Toast.makeText(this, "Connection Failure : " + 
  connectionResult.getErrorCode(),
  Toast.LENGTH_SHORT).show();
}
public void displayCurrentLocation() {
  // Get the current location's latitude & longitude
  Location currentLocation = mLocationClient.getLastLocation();
  String msg = "Current Location: " +
  Double.toString(currentLocation.getLatitude()) + "," +
  Double.toString(currentLocation.getLongitude());

  // Display the current location in the UI
  locationLabel.setText(msg);

  // To display the current address in the UI
  (new GetAddressTask(this)).execute(currentLocation);
 }
/*
 * Following is a subclass of AsyncTask which has been used to get
 * address corresponding to the given latitude & longitude.
 */
 private class GetAddressTask extends AsyncTask<Location, Void, String>{
  Context mContext;
  public GetAddressTask(Context context) {
     super();
     mContext = context;
  }

  /*
   * When the task finishes, onPostExecute() displays the address. 
   */
  @Override
  protected void onPostExecute(String address) {
     // Display the current address in the UI
     addressLabel.setText(address);
  }
  @Override
  protected String doInBackground(Location... params) {
     Geocoder geocoder =
     new Geocoder(mContext, Locale.getDefault());
     // Get the current location from the input parameter list
     Location loc = params[0];
     // Create a list to contain the result address
     List<Address> addresses = null;
     try {
        addresses = geocoder.getFromLocation(loc.getLatitude(),
        loc.getLongitude(), 1);
     } catch (IOException e1) {
        Log.e("LocationSampleActivity", 
        "IO Exception in getFromLocation()");
        e1.printStackTrace();
        return ("IO Exception trying to get address");
     } catch (IllegalArgumentException e2) {
        // Error message to post in the log
        String errorString = "Illegal arguments " +
        Double.toString(loc.getLatitude()) +
        " , " +
        Double.toString(loc.getLongitude()) +
        " passed to address service";
        Log.e("LocationSampleActivity", errorString);
        e2.printStackTrace();
        return errorString;
     }
     // If the reverse geocode returned an address
     if (addresses != null && addresses.size() > 0) {
        // Get the first address
        Address address = addresses.get(0);
        /*
        * Format the first line of address (if available),
        * city, and country name.
        */
        String addressText = String.format(
        "%s, %s, %s",
        // If there's a street address, add it
        address.getMaxAddressLineIndex() > 0 ?
        address.getAddressLine(0) : "",
        // Locality is usually a city
        address.getLocality(),
        // The country of the address
        address.getCountryName());
        // Return the text
        return addressText;
     } else {
        return "No address found";
     }
  }
}// AsyncTask class
}

Refrence link http://www.tutorialspoint.com/android/android_location_based_services.htm