我在android studio中的位置问题

Question

晚上好大家我想告诉你我的问题，所以我希望在谷歌地图中我的android出现了我的当前位置的按钮，但当我在我的真实手机（三星SM-J730G android 7.0 api 24）中尝试它小按钮没有出现（我没有在模拟器中尝试它导致我也不工作）。所以我想知道问题是什么，请朋友们帮助我，感谢您的帮助，代码是：

public class MapFragment extends Fragment implements View.OnClickListener {


private View rootView;
private MapView mapView;
private GoogleMap mMap;
private FloatingActionButton fab;


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


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    this.rootView = inflater.inflate(R.layout.fragment_map, container, false);
    this.fab = (FloatingActionButton) rootView.findViewById(R.id.fab);
    return rootView;
}


 @Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
    this.fab.setOnClickListener(this);
    this.mapView = (MapView) this.rootView.findViewById(R.id.map);
    if (mapView != null) {
        this.mapView.onCreate(null);
        this.mapView.onResume();
        this.mapView.getMapAsync(new OnMapReadyCallback() {
            @Override
            public void onMapReady(GoogleMap googleMap) {
                mMap = googleMap;
                if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    return;
                }
                mMap.setMyLocationEnabled(true); //I DONT KNOW WHY IT DOES NOT WORK


                  }
              });

    }



    super.onViewCreated(view, savedInstanceState);
}

哦，顺便说一下我把它和它一起去了

 if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    return;   //is entrying here and i donw know why if i have the perssions in the manifest the accces_fine_location and acces_coarse_location
                }
                mMap.setMyLocationEnabled(true);   


please somebody help me thanks you

Answer 1

您只检查了运行时权限，如果没有提供您没有请求权限。更新下面的代码和onRequestPermissionsResult检查是否提供了权限从那里设置mMap.setMyLocationEnabled(true);

     @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        this.fab.setOnClickListener(this);
        this.mapView = (MapView) this.rootView.findViewById(R.id.map);
        if (mapView != null) {
           his.mapView.getMapAsync(new OnMapReadyCallback() {
                @Override
                public void onMapReady(GoogleMap googleMap) {
                    mMap = googleMap;
                    if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

  ActivityCompat.requestPermissions(context, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, 101);
                        return;
                    }
                    mMap.setMyLocationEnabled(true); //I DONT KNOW WHY IT DOES NOT WORK


                      }
                  });

        }

在许可结果上

@Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == 101) {
  f (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
mMap.setMyLocationEnabled(true);  }
  }                 
}

Answer 2

此外，它有助于确保在使用地图时始终启用GPS。