Question

我正在尝试制作一款可以跟踪我的自行车GPS位置的应用。首先，我一直在尝试阅读自己手机的GPS位置。每当我尝试启动下面的片段时，我的应用都会崩溃。我为应用程序添加了一个Google API密钥，并将行“”放在我的清单文件中。调试此问题有哪些好方法？我是Android Studio的新手，所以我很乐意听到任何反馈。

//FindBikeFragment.java

import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.google.android.gms.location.FusedLocationProviderClient;
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.MarkerOptions;


/**
 * A simple {@link Fragment} subclass.
 */
public class FindBikeFragment extends Fragment implements OnMapReadyCallback {

    /**
     * GoogleMaps object
     */
    private GoogleMap mMap;
    /**
     * Provides the entry point to the Fused Location Provider API.
     */
    private FusedLocationProviderClient mFusedLocationClient;
    /**
     * Represents a geographical location.
     */
    protected Location mLastLocation;


    public FindBikeFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View v = inflater.inflate(R.layout.fragment_find_bike, container, false);
        return v;
    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map1);
        mapFragment.getMapAsync(this);
    }


    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        mFusedLocationClient = LocationServices.getFusedLocationProviderClient(getActivity());

        if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getContext(), 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.
            mLastLocation = mFusedLocationClient.getLastLocation().getResult();
            LatLng pp = new LatLng(mLastLocation.getLatitude(), mLastLocation.getLongitude());
            MarkerOptions option = new MarkerOptions();
            option.position(pp).title("Some City");
            mMap.addMarker(option);
            mMap.moveCamera(CameraUpdateFactory.newLatLng(pp));
            return;
        }
    }
}

Answer 1

您需要将GoogleApiClient用于FusedLocationApi.Here是一个正常工作的代码

    protected synchronized void buildGoogleApiClient() {
         mGoogleApiClient = new GoogleApiClient.Builder(this)
        .addConnectionCallbacks(this)
        .addOnConnectionFailedListener(this)
        .addApi(LocationServices.API)
        .build();}

    return;
}

在onCreate（）上调用buildGoogleApiClient方法。并实现所需的接口。 GoogleApiClient.ConnectionCallbacks，GoogleApiClient.OnConnectionFailedListener， LocationListener的

 @Override
public void onConnected(@Nullable Bundle bundle) {
    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 mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
            mGoogleApiClient);
    if (mLastLocation != null) {
        //place marker at current position
        // Log.e("x", mLastLocation.getLongitude() + "");
        //Log.e("y", mLastLocation.getLatitude() + "");
        currentLocation = mLastLocation;


    }

    LocationRequest mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(5000); //5 seconds
    mLocationRequest.setFastestInterval(5000); //3 seconds
    mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
    mLocationRequest.setSmallestDisplacement(50F); //1/10 meter

    LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}

@Override
public void onConnectionSuspended(int i) {

}

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

}

@Override
public void onLocationChanged(Location location) {

    currentLocation = location;

}

并定义此参数

private GoogleApiClient mGoogleApiClient;
private Location currentLocation;

顺便说一句，如果您使用的是Android 6.x或7.x版本。您需要在运行时授予权限。检查here

Answer 2

@FnR你正在谈论旧版本的融合位置，一个新的版本出现在游戏服务的版本11中，它应该更简单，看看这里：{{3} }

我遇到了同样的问题，新的fusedlocationapi和地图活动之间似乎存在冲突。我能够在没有地图的空活动中使用这种新技术获取当前位置，但地图活动中使用的完全相同的代码会返回空结果。

谷歌甚至没有用地图提供任何这方面的例子，这很疯狂，因为获得该位置的时间是99％加上地图

Android应用随FusedLocationProvider

2 个答案: