使用 Geofence 获取用户的坐标将不起作用

Question

我想要做的是在应用加载时获取用户位置，然后在单击按钮时，我希望应用检查用户的距离是否在我所需位置的半径范围内，然后它会做某事

位置是我遇到的问题...我正在尝试以最简单的方式获取用户的位置，因为我只需要它来检查用户是否在或 "around" 位置

这是我获取用户位置的代码（符合要求但应用程序崩溃）：

if (ContextCompat.checkSelfPermission(this,
    Manifest.permission.READ_CONTACTS)
    != PackageManager.PERMISSION_GRANTED) {

    LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

    Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);


    double longitude = location.getLongitude();
    double latitude = location.getLatitude();

    List<Geofence> mGeofenceList = new ArrayList<Geofence>();

    mGeofenceList.add(new Geofence.Builder()
        .setRequestId("Request ID")
        .setCircularRegion(latitude, longitude, 480f)
        .setExpirationDuration(300000) // duration is in millis (5mins)
        .setTransitionTypes(Geofence.GEOFENCE_TRANSITION_ENTER | Geofence.GEOFENCE_TRANSITION_EXIT)
        .build());
}

Answer 1

尝试像下面这样使用位置侦听器。

public class MainActivity extends Activity implements LocationListener{
protected LocationManager locationManager;
protected LocationListener locationListener;
protected Context context;
TextView txtLat;
String lat;
String provider;
protected String latitude,longitude; 
protected boolean gps_enabled,network_enabled;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txtLat = (TextView) findViewById(R.id.textview1);

locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
}
@Override
public void onLocationChanged(Location location) {
txtLat = (TextView) findViewById(R.id.textview1);
double lat = location.getLatitude(); 
double longi = location.getLongitude();
txtLat.setText("Latitude:" + location.getLatitude() + ", Longitude:" +    location.getLongitude());
}

@Override
public void onProviderDisabled(String provider) {
Log.d("Latitude","disable");
}

@Override
public void onProviderEnabled(String provider) {
Log.d("Latitude","enable");
}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Log.d("Latitude","status");
}
}

权限：

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

您将在 onLocationChanged() 方法中获取当前经纬度值。将此纬度和经度值添加到您的 mGeofenceList 列表中。

使用 Geofence 获取用户的坐标将不起作用

Getting the user's coordinates using Geofence will not work

java

android

location

geofencing