Current Location not auto display to the textview

问题

Currently I want to get the user current location of latitude and longitude but my code can get until I pressed the send button in the emulator setting but what I want is to auto get the location and set it to the textview so what should I do? Anyone please advice me to solve this problem please because I really not familiar with the location code.

Here's my code

package com.example.rex.ota30;

import android.*;
import android.Manifest;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.provider.Settings;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;

import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

import static com.example.rex.ota30.R.id.textView;

public class Search extends AppCompatActivity implements LocationListener {

private FirebaseDatabase db;
private DatabaseReference sref, lref;
private TextView searchun, searchlo, searchla;
private String un, la, lo;
private LocationManager lm;
private LocationListener ll;

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

    db = FirebaseDatabase.getInstance();

    sref = db.getReference("users");
    lref = db.getReference("userslocation");

    searchun = (TextView) findViewById(R.id.sun);
    Intent i = this.getIntent();
    un = i.getStringExtra("username");
    searchun.setText(un);

    searchlo = (TextView) findViewById(R.id.slo);
    searchla = (TextView) findViewById(R.id.sla);

    lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

        return;
    }
    lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, (LocationListener) this);
}

@Override
public void onLocationChanged(Location location) {

    la = String.valueOf(location.getLatitude());
    searchla.setText(la);

    lo = String.valueOf(location.getLongitude());
    searchlo.setText(lo);

    lref.child(un).child("latitude").setValue(la);
    lref.child(un).child("longitude").setValue(lo);
}

@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");
}
}

Here's the sample of the getting location.

回答1:

OnLocationChanged is only called when the location has changed.
So the location is displayed in the Textview only when the send button is pressed.
If you want to display the location from the beginning, try this

protected void onCreate(Bundle savedInstanceState) {
  ...
  lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, (LocationListener) this);
  ...
  // add code
  Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
  la = String.valueOf(location.getLatitude());
  searchla.setText(la);

  lo = String.valueOf(location.getLongitude());
  searchlo.setText(lo);
}

回答2:

import android.content.pm.PackageManager;
import android.location.Location;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
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.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 OnMapReadyCallback,
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener,
        GoogleMap.OnMarkerDragListener,
        GoogleMap.OnMapLongClickListener,
        GoogleMap.OnMarkerClickListener,
        View.OnClickListener {

    private static final String TAG = "MapsActivity";
    private GoogleMap mMap;
    private double longitude;
    private double latitude;
    private GoogleApiClient googleApiClient;


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

        // 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);

        //Initializing googleApiClient
        googleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }


    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
       // googleMapOptions.mapType(googleMap.MAP_TYPE_HYBRID)
                    //    .compassEnabled(true);

        // Add a marker in Sydney and move the camera
        LatLng india = new LatLng(-34, 151);
        mMap.addMarker(new MarkerOptions().position(india).title("Marker in India"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(india));
        mMap.setOnMarkerDragListener(this);
        mMap.setOnMapLongClickListener(this);
    }

    //Getting current location
    private void getCurrentLocation() {
        mMap.clear();
        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
            //    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;
        }
        Location location = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);
        if (location != null) {
            //Getting longitude and latitude
            longitude = location.getLongitude();
            latitude = location.getLatitude();

            //moving the map to location
            moveMap();
        }
    }

    private void moveMap() {
        /**
         * Creating the latlng object to store lat, long coordinates
         * adding marker to map
         * move the camera with animation
         */
        LatLng latLng = new LatLng(latitude, longitude);
        mMap.addMarker(new MarkerOptions()
                .position(latLng)
                .draggable(true)
                .title("Marker in India"));

        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        mMap.animateCamera(CameraUpdateFactory.zoomTo(15));
        mMap.getUiSettings().setZoomControlsEnabled(true);


    }

    @Override
    public void onClick(View view) {
        Log.v(TAG,"view click event");
    }

    @Override
    public void onConnected(@Nullable Bundle bundle) {
        getCurrentLocation();
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

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

    }

    @Override
    public void onMapLongClick(LatLng latLng) {
        // mMap.clear();
        mMap.addMarker(new MarkerOptions().position(latLng).draggable(true));
    }

    @Override
    public void onMarkerDragStart(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerDragStart", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onMarkerDrag(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerDrag", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onMarkerDragEnd(Marker marker) {
        // getting the Co-ordinates
        latitude = marker.getPosition().latitude;
        longitude = marker.getPosition().longitude;

        //move to current position
        moveMap();
    }

    @Override
    protected void onStart() {
        googleApiClient.connect();
        super.onStart();
    }

    @Override
    protected void onStop() {
        googleApiClient.disconnect();
        super.onStop();
    }


    @Override
    public boolean onMarkerClick(Marker marker) {
        Toast.makeText(MapsActivity.this, "onMarkerClick", Toast.LENGTH_SHORT).show();
        return true;
    }

}

来源：https://stackoverflow.com/questions/46293122/current-location-not-auto-display-to-the-textview

标签

android

location

locationmanager