位置更改了问题

Question

我正在开发一个应用程序，它可以查找用户的位置并定位在接入点和信号区域附近。

当我通过按钮手动请求位置更新时，它只是不调用回调函数。

这是我的活动：

public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener, OnMapReadyCallback, LocationListener{
//LOG tag
private static final String LOG = MainActivity.class.getSimpleName();
private static final String DEBUG = "Debugging MainActivity:";
private static final String TEST = "Test";
private static final float ZOOM_LEVEL = 15.5f;
//The map
private GoogleMap mGmap;
private LocationManager mLocationManager;
private Location mLocation;
private WifiManager mWifiManager;
private BroadcastReceiver mBroadcastReceiver;
private List<ScanResult> mResultList;
private String mProvider;
private Criteria mCriteria;
//Controller
private AccessPointController mController;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Toolbar
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
mController = new AccessPointController();
startReceivingLocationUpdates();
mCriteria = new Criteria();
mCriteria.setAccuracy(Criteria.ACCURACY_COARSE);
mCriteria.setPowerRequirement(Criteria.POWER_MEDIUM);
mProvider = mLocationManager.getBestProvider(mCriteria, false);
Log.i(DEBUG, mProvider);
mBroadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context c, Intent intent) {
if(intent.getAction() == WifiManager.SCAN_RESULTS_AVAILABLE_ACTION) {
mResultList = mWifiManager.getScanResults();
mController.setApList(mResultList);
}
}
};
mWifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
registerReceiver(mBroadcastReceiver, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
mWifiManager.startScan();
//Map handling
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
private void startReceivingLocationUpdates() {
if(mLocationManager == null) {
mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
}
}
@Override
public void onLocationChanged(Location location) {
Log.i(DEBUG, "onLocationChanged");
mLocation = new Location(location);
mController.setCurrentPosition(mLocation);
Log.i(DEBUG, "setted new position");
mController.showOnMap(mGmap);
mGmap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(mLocation.getLatitude(), mLocation.getLongitude()), ZOOM_LEVEL));
}
@Override
protected void onResume() {
super.onResume();
try {
mLocationManager.requestSingleUpdate(mProvider, this, null);
} catch(SecurityException e) {
System.out.println("OnResume Error: " + e.getMessage());
}
}
@Override
protected void onPause() {
super.onPause();
mLocationManager.removeUpdates(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
Log.i(DEBUG, "onMapReady");
mGmap = googleMap;
try {
mLocation = mLocationManager.getLastKnownLocation(mProvider);
mController.setCurrentPosition(mLocation);
} catch(SecurityException e) {
e.printStackTrace();
}
mGmap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(mLocation.getLatitude(), mLocation.getLongitude()), ZOOM_LEVEL));
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_explore) {
try {
if(mLocationManager != null) {
try {
Log.i(DEBUG, "manual update request");
mLocationManager.requestSingleUpdate(mProvider, this, null);
} catch (SecurityException e) {
Toast.makeText(this, "Failed to request location updates, ignore: " + e.getMessage(), Toast.LENGTH_SHORT).show();
} catch (IllegalArgumentException e) {
Toast.makeText(this, "Provider does not exist: " + e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
} catch (SecurityException e) {
e.printStackTrace();
}
} else if (id == R.id.nav_open_networks) {
Toast.makeText(this, "Open network pressed", Toast.LENGTH_SHORT).show();
} else if (id == R.id.nav_closed_networks) {
Toast.makeText(this, "Closed network pressed", Toast.LENGTH_SHORT).show();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}

}

基本上，当用户按下浏览按钮时，应用程序应该找到用户并在地图上显示他。

这是日志猫：

/调试主活动：： 网络

/调试主活动：： onMapReady

/调试控制器：：设置位置

/调试主活动：：手动更新请求

和/调试主活动：： onLocationChanged 永远不会显示。

我还尝试使用变量作为位置侦听器，它不起作用。 是的，我在清单中的权限很好。

我真的不明白我做错了什么。

Answer 1

由于映射是异步加载的，因此要求在onMapReady((方法中执行操作还为时过早。

将 LocationManager 方法替换为 FusedLocation 方法允许我等到建立连接，然后进行计算。