我目前的目标是将LatLng发送到Firebase。我确实做到了这一点，但我现在遇到的问题是，在对Firebase进行了几次更新之后，我的位置字段开始超快速地接收更新，这反过来又滞后于我的应用程序并且还增加了我的手机温度。
如何在没有应用程序延迟的情况下每分钟两次向firebase发送位置更新？
我使用onLocationChanged(Location)方法将位置更新发送到Firebase。
这是我的Mapfragment类。
import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Build;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;
import com.firebase.client.DataSnapshot;
import com.firebase.client.Firebase;
import com.firebase.client.FirebaseError;
import com.firebase.client.ValueEventListener;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
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.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.mycompany.neighbors.MainActivity;
import com.mycompany.neighbors.R;
import com.mycompany.neighbors.User;
/**
* Created by joshua on 5/25/2016.
*/
public class MapFragment extends Fragment implements OnMapReadyCallback,LocationListener, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener{
private GoogleApiClient mGoogleApiClient;
private final String FIREBASE_URL = "MY_URL";
private static final int MY_PERMISSIONS_REQUEST_FINE_LOCATION = 101;
SupportMapFragment mSupportMapFragment;
private GoogleMap maps;
private boolean permissionIsGranted = false;
private LatLng mLatLng;
private User mApplicationUser;
private static String mApplicationUserUID;
public static MapFragment newInstance(int index){
MapFragment mapFragment = new MapFragment();
Bundle args = new Bundle();
args.putInt("index",index);
mapFragment.setArguments(args);
return mapFragment;
}
private void createMap(){
mSupportMapFragment = SupportMapFragment.newInstance();
FragmentManager fm = getFragmentManager();
mSupportMapFragment.getMapAsync(this);
if(!mSupportMapFragment.isAdded())
fm.beginTransaction().add(R.id.map_frag,mSupportMapFragment).commit();
else if(mSupportMapFragment.isAdded())
fm.beginTransaction().hide(mSupportMapFragment).commit();
else
fm.beginTransaction().show(mSupportMapFragment).commit();
}
private void requestLocationUpdates() {
LocationRequest mLocationRequest = new LocationRequest();
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setInterval(60000);
if (ActivityCompat.checkSelfPermission(getContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getContext(), android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSIONS_REQUEST_FINE_LOCATION);
}
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
/////////////////////////////////////////OVERRIDE METHODS////////////////////////////////////////////////////////////
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View v = inflater.inflate(R.layout.fragment_map,container,false);
mApplicationUserUID = MainActivity.getUID();
mGoogleApiClient = new GoogleApiClient.Builder(getActivity())
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
createMap();
return v;
}
////////////////////////////////////////LIFECYCLE METHODS///////////////////////////////////////////////////////////
@Override
public void onStart(){
super.onStart();
mGoogleApiClient.connect();
}
@Override
public void onResume(){
super.onResume();
if(permissionIsGranted){
if(mGoogleApiClient.isConnected()){
requestLocationUpdates();
}
}
}
@Override
public void onStop(){
if(permissionIsGranted){
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient,this);
mGoogleApiClient.disconnect();
}
super.onStop();
}
///////////////////////LIFECYCLE METHODS//////////////////////////////////////////////
@Override
public void onMapReady(GoogleMap googleMap) {
maps = googleMap;
}
@Override
public void onConnected(@Nullable Bundle bundle) {
Log.d("TAG_JOSH", "onConnected");
requestLocationUpdates();
}
@Override
public void onConnectionSuspended(int i) {
Log.d("TAG_JOSH", "Connection suspended");
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
Log.d("TAG_JOSH", "Connection failed");
}
@Override
public void onLocationChanged(final Location location) {
Log.d("TAG_JOSH","Latitude: " +Double.toString(location.getLatitude()));
final LatLng coordinates = new LatLng(location.getLatitude(),location.getLongitude());
final Firebase userRef = new Firebase("MY_URL");
userRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
userRef.setValue(coordinates);
}
@Override
public void onCancelled(FirebaseError firebaseError) {
}
});
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults){
super.onRequestPermissionsResult(requestCode,permissions,grantResults);
switch(requestCode){
case MY_PERMISSIONS_REQUEST_FINE_LOCATION:
if(grantResults[0] == PackageManager.PERMISSION_GRANTED){
//Permission granted
permissionIsGranted = true;
} else{
//Permission denied
permissionIsGranted = false;
Toast.makeText(getContext(),"This app requires location permissions", Toast.LENGTH_SHORT).show();
}
break;
}
}
/////////////////////////////////////////OVERRIDE METHODS////////////////////////////////////////////////////////////
}
答案 0 :(得分：0)
如果您尝试每分钟发送一次您的位置，则需要删除Firebase内onLocationChanged内发送位置更新的部分内容。
添加CountDownTimer并触发，以便在每30秒过后发送一次位置更新。
所以你需要做这样的事情。
取两个全局变量
private Location currentLocation;
private Location previousLocation;
现在你的onCreateView内部会声明一个像这样的计时器。
new CountDownTimer(30000, 1000) { // 30 seconds timer
public void onTick(long millisUntilFinished) {
// Do nothing
}
public void onFinish() {
// Send location update to firebase here if the previous location sent to server and the current location is not the same.
final LatLng coordinates = new LatLng(currentLocation.getLatitude(),currentLocation.getLongitude());
if(currentLocation == previousLocation) return; // Pseudo code
final Firebase userRef = new Firebase("MY_URL");
userRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
userRef.setValue(coordinates);
}
@Override
public void onCancelled(FirebaseError firebaseError) {
}
});
// Now start the timer from here again.
this.start(); // Pseudo code.
}
}.start();
在onLocationChanged功能中，只需像这样更新currentLocation
@Override
public void onLocationChanged(final Location location) {
currentLocation = location; // Update the current location here
}