如何使一个简单的跟踪android应用程序使用android工作室

我想做一个简单的位置跟踪应用程序我尝试了很多方法，但没有任何工作。我认为onLocationChanged没有被调用。如何使一个简单的跟踪android应用程序使用android工作室

这里是我的代码：

@Override 
public void onLocationChanged(Location location) { 
    Log.d("test", "onLocationChanged Called"); 
    double latitude = location.getLatitude(); 
    double longitude = location.getLongitude(); 
    LatLng latLng = new LatLng(latitude, longitude); 
    gMap.addMarker(new MarkerOptions().position(latLng)); 
    gMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
    gMap.animateCamera(CameraUpdateFactory.zoomTo(15)); 
    Log.d("location", "Latitude:" + latitude + ", Longitude:" + longitude); 
}

来源

2017-04-10 Chandan Kumar

您是否在追踪之前请求'ACCESS_FINE_LOCATION'权限？ – dewarder

是.................................. @ Google –

@ChandanKumar公共资源很多。请做一个研究，并回来一个很好的解释。 http://stackoverflow.com/help/how-to-ask – Stallion

这里是我的全部代码来运行应用程序。刚刚作出新的项目，然后选择地图项目，将谷歌控制台上的项目和密钥添加到您的项目：

添加权限来体现：

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

Java代码：

package com.bluebirds.avinash.uberdemo; 

import android.Manifest; 
import android.content.pm.PackageManager; 
import android.graphics.Point; 
import android.location.Location; 
import android.os.Bundle; 
import android.os.Handler; 
import android.os.Message; 
import android.os.SystemClock; 
import android.support.annotation.NonNull; 
import android.support.annotation.Nullable; 
import android.support.v4.app.ActivityCompat; 
import android.support.v4.app.FragmentActivity; 
import android.support.v4.content.ContextCompat; 
import android.util.Log; 
import android.view.animation.Interpolator; 
import android.view.animation.LinearInterpolator; 
import android.widget.Button; 
import android.widget.TextView; 

import com.google.android.gms.common.ConnectionResult; 
import com.google.android.gms.common.api.GoogleApiClient; 
import com.google.android.gms.common.api.PendingResult; 
import com.google.android.gms.common.api.Status; 
import com.google.android.gms.location.LocationListener; 
import com.google.android.gms.location.LocationRequest; 
import com.google.android.gms.location.LocationServices; 
import com.google.android.gms.maps.CameraUpdateFactory; 
import com.google.android.gms.maps.GoogleMap; 
import com.google.android.gms.maps.OnMapReadyCallback; 
import com.google.android.gms.maps.Projection; 
import com.google.android.gms.maps.SupportMapFragment; 
import com.google.android.gms.maps.model.LatLng; 
import com.google.android.gms.maps.model.Marker; 
import com.google.android.gms.maps.model.MarkerOptions; 

public class MapsActivity extends FragmentActivity implements LocationListener, 
     OnMapReadyCallback, GoogleApiClient 
       .ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener { 

    private GoogleMap mMap; 
    private final int MY_LOCATION_REQUEST_CODE = 100; 
    private Handler handler; 
    private Marker m; 
// private GoogleApiClient googleApiClient; 

    public final static int SENDING = 1; 
    public final static int CONNECTING = 2; 
    public final static int ERROR = 3; 
    public final static int SENT = 4; 
    public final static int SHUTDOWN = 5; 

    private static final String TAG = "LocationActivity"; 
    private static final long INTERVAL = 1000 * 10; 
    private static final long FASTEST_INTERVAL = 1000 * 5; 
    Button btnFusedLocation; 
    TextView tvLocation; 
    LocationRequest mLocationRequest; 
    GoogleApiClient mGoogleApiClient; 
    Location mCurrentLocation; 
    String mLastUpdateTime; 
    private Location previousLocation; 

    protected void createLocationRequest() { 
     mLocationRequest = new LocationRequest(); 
     mLocationRequest.setInterval(INTERVAL); 
     mLocationRequest.setFastestInterval(FASTEST_INTERVAL); 
     mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY); 
    } 

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

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

     // Obtain the SupportMapFragment and get notified when the map is ready to be used. 
     SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() 
       .findFragmentById(R.id.map); 
     mapFragment.getMapAsync(this); 

     handler = new Handler() { 
      @Override 
      public void handleMessage(Message msg) { 
       switch (msg.what) { 

        case SENDING: 

         break; 

       } 

      } 
     }; 
    } 


    /** 
    * Manipulates the map once available. 
    * This callback is triggered when the map is ready to be used. 
    * This is where we can add markers or lines, add listeners or move the camera. In this case, 
    * we just add a marker near Sydney, Australia. 
    * If Google Play services is not installed on the device, the user will be prompted to install 
    * it inside the SupportMapFragment. This method will only be triggered once the user has 
    * installed Google Play services and returned to the app. 
    */ 
    @Override 
    public void onMapReady(GoogleMap googleMap) { 
     mMap = googleMap; 

     // Add a marker in Sydney and move the camera 
     LatLng sydney = new LatLng(-34, 151); 

     m = mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in " + 
       "Sydney")); 
     mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney)); 


     if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) 
       == PackageManager.PERMISSION_GRANTED) { 
      mMap.setMyLocationEnabled(true); 
     } else { 
      // Show rationale and request permission. 
     } 


    } 


    public void rotateMarker(final Marker marker, final float toRotation, final float st) { 
     final Handler handler = new Handler(); 
     final long start = SystemClock.uptimeMillis(); 
     final float startRotation = st; 
     final long duration = 1555; 

     final Interpolator interpolator = new LinearInterpolator(); 

     handler.post(new Runnable() { 
      @Override 
      public void run() { 
       long elapsed = SystemClock.uptimeMillis() - start; 
       float t = interpolator.getInterpolation((float) elapsed/duration); 

       float rot = t * toRotation + (1 - t) * startRotation; 

       marker.setRotation(-rot > 180 ? rot/2 : rot); 
       if (t < 1.0) { 
        // Post again 16ms later. 
        handler.postDelayed(this, 16); 
       } 
      } 
     }); 
    } 


    public void animateMarker(final LatLng toPosition, final boolean hideMarke) { 
     final Handler handler = new Handler(); 
     final long start = SystemClock.uptimeMillis(); 
     Projection proj = mMap.getProjection(); 
     Point startPoint = proj.toScreenLocation(m.getPosition()); 
     final LatLng startLatLng = proj.fromScreenLocation(startPoint); 
     final long duration = 5000; 

     final Interpolator interpolator = new LinearInterpolator(); 

     handler.post(new Runnable() { 
      @Override 
      public void run() { 
       long elapsed = SystemClock.uptimeMillis() - start; 
       float t = interpolator.getInterpolation((float) elapsed 
         /duration); 
       double lng = t * toPosition.longitude + (1 - t) 
         * startLatLng.longitude; 
       double lat = t * toPosition.latitude + (1 - t) 
         * startLatLng.latitude; 
       m.setPosition(new LatLng(lat, lng)); 

       if (t < 1.0) { 
        // Post again 16ms later. 
        handler.postDelayed(this, 16); 
       } else { 
        if (hideMarke) { 
         m.setVisible(false); 
        } else { 
         m.setVisible(true); 
        } 
       } 
      } 
     }); 
    } 

    private double bearingBetweenLocations(LatLng latLng1, LatLng latLng2) { 

     double PI = 3.14159; 
     double lat1 = latLng1.latitude * PI/180; 
     double long1 = latLng1.longitude * PI/180; 
     double lat2 = latLng2.latitude * PI/180; 
     double long2 = latLng2.longitude * PI/180; 

     double dLon = (long2 - long1); 

     double y = Math.sin(dLon) * Math.cos(lat2); 
     double x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) 
       * Math.cos(lat2) * Math.cos(dLon); 

     double brng = Math.atan2(y, x); 

     brng = Math.toDegrees(brng); 
     brng = (brng + 360) % 360; 

     return brng; 
    } 


    /* @Override 
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] 
      grantResults) { 
     if (requestCode == MY_LOCATION_REQUEST_CODE) { 
      if (permissions.length == 1 && 
        permissions[0] == Manifest.permission.ACCESS_FINE_LOCATION && 
        grantResults[0] == PackageManager.PERMISSION_GRANTED) { 
       mMap.setMyLocationEnabled(true); 
      } else { 
       // Permission was denied. Display an error message. 
      } 
     } 
    }*/ 

    @Override 
    public void onConnected(@Nullable Bundle bundle) { 

     Log.d(TAG, "onConnected - isConnected ...............: " + mGoogleApiClient.isConnected()); 
     startLocationUpdates(); 
    } 

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

    @Override 
    protected void onStop() { 
     super.onStop(); 

     mGoogleApiClient.disconnect(); 
     Log.d(TAG, "isConnected ...............: " + mGoogleApiClient.isConnected()); 
    } 

    @Override 
    public void onConnectionSuspended(int i) { 

    } 

    @Override 
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) { 

    } 

    protected void startLocationUpdates() { 
     if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != 
       PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 
       Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
      // TODO: Consider calling 
      // ActivityCompat#requestPermissions 
      // here to request the missing permissions, and then overriding 
      // public void onRequestPermissionsResult(int requestCode, String[] permissions, 
      //           int[] grantResults) 
      // to handle the case where the user grants the permission. See the documentation 
      // for ActivityCompat#requestPermissions for more details. 
      return; 
     } 
     PendingResult<Status> pendingResult = LocationServices.FusedLocationApi 
       .requestLocationUpdates(mGoogleApiClient, mLocationRequest, this); 
     Log.d(TAG, "Location update started ..............: "); 
    } 

    LatLng previouslatLng; 

    @Override 
    public void onLocationChanged(Location location) { 
     previouslatLng = new LatLng(location.getLatitude(), location.getLongitude()); 

     double rota = 0.0; 
     double startrota = 0.0; 
     if (previousLocation != null) { 

      rota = bearingBetweenLocations(previouslatLng, new LatLng(location.getLatitude 
        (), location.getLongitude())); 
     } 


     rotateMarker(m, (float) rota, (float) startrota); 


     previousLocation = location; 
     Log.d(TAG, "Firing onLocationChanged.........................."); 
     Log.d(TAG, "lat :" + location.getLatitude() + "long :" + location.getLongitude()); 
     Log.d(TAG, "bearing :" + location.getBearing()); 

     animateMarker(new LatLng(location.getLatitude(), location.getLongitude()), false); 
//  new ServerConnAsync(handler, MapsActivity.this,location).execute(); 


    } 

    @Override 
    protected void onPause() { 
     super.onPause(); 
     stopLocationUpdates(); 
    } 

    protected void stopLocationUpdates() { 
     LocationServices.FusedLocationApi.removeLocationUpdates(
       mGoogleApiClient, this); 
     Log.d(TAG, "Location update stopped ......................."); 
    } 

    @Override 
    public void onResume() { 
     super.onResume(); 
     if (mGoogleApiClient.isConnected()) { 
      startLocationUpdates(); 
      Log.d(TAG, "Location update resumed ....................."); 
     } 
    } 
}

XML活动：

<fragment android:id="@+id/map" 
      android:name="com.google.android.gms.maps.SupportMapFragment" 
      xmlns:android="http://schemas.android.com/apk/res/android" 
      xmlns:map="http://schemas.android.com/apk/res-auto" 
      xmlns:tools="http://schemas.android.com/tools" 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      tools:context="com.bluebirds.avinash.uberdemo.MapsActivity"/>

来源

2017-04-10 09:08:50

这只是在悉尼展示一个标记。 –

您的位置服务。或下载fakelocation应用程序。打开你的模拟位置。移动您的当前位置，您将看到标记正在根据您的位置移动。 –

以此作为参考项目： - http://www.vogella.com/tutorials/AndroidLocationAPI/article.html

来源

2017-04-10 09:11:32 Hangman

onLocationChanged未调用 –

仔细复制代码。本教程100％正确。 – Hangman

我是复制粘贴专家 –

如何使一个简单的跟踪android应用程序使用android工作室

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