java - 设置 setMylocationenable(true) 时无法获取谷歌地图 fragment 中的 Activity 上下文

Question

尝试影响 fragment 中的当前位置。在获得许可的同时，不停止获取 Activity 上下文。我在其他 fragment 中获取 Activity 上下文，但不知道为什么它显示错误

mMap.setMyLocationEnabled(true);

请帮忙

古尔 map fragment :

package com.example.mudasir.login.fragments;    

import android.Manifest;
import android.app.ProgressDialog;
import android.content.pm.PackageManager;
import android.content.res.Resources;
import android.location.Address;
import android.location.Geocoder;
import android.os.AsyncTask;
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 android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.example.mudasir.login.R;
import com.google.android.gms.maps.CameraUpdate;
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.LatLngBounds;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

import java.io.IOException;
import java.util.List;


/**
 * A simple {@link Fragment} subclass.
 */
public class LocatorsFragment extends Fragment implements OnMapReadyCallback, View.OnClickListener {

    private GoogleMap mMap;
    private Button btnShowroom;
    private Button btnService;
    private Button btnParts;
    private Button btnGas;
    private Button btnAtm;
    private Button btnSearch;
    private EditText searchQuery;


    Resources stringArrayResource;
    private String[] showroomAddresses;
    private String[] serviceAddresses;
    private String[] partsAddresses;
    private String searchQueryString;
    private android.location.Address address = null;
    List<Address> addressList = null;

    LatLng latLng;
    Geocoder geocoder;
    Marker marker;
    LatLngBounds bounds;
    CameraUpdate cu;
    ProgressDialog dialog;
    boolean flag = false;

    public LocatorsFragment() {
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_maps_, container, false);
        initUI(view);
        return view;
    }

    private void initUI(View view) {
        btnShowroom = (Button) view.findViewById(R.id.btn_showroom);
        btnService = (Button) view.findViewById(R.id.btn_service);
        btnParts = (Button) view.findViewById(R.id.btn_parts);
        btnGas = (Button) view.findViewById(R.id.btn_gas);
        btnAtm = (Button) view.findViewById(R.id.btn_atm);
        btnSearch = (Button) view.findViewById(R.id.btn_search);
        searchQuery = (EditText) view.findViewById(R.id.editext_search);

        btnShowroom.setOnClickListener(this);
        btnService.setOnClickListener(this);
        btnParts.setOnClickListener(this);
        btnGas.setOnClickListener(this);
        btnAtm.setOnClickListener(this);
        btnSearch.setOnClickListener(this);

        stringArrayResource = getActivity().getResources();
        showroomAddresses = stringArrayResource.getStringArray(R.array.showroom_array);
        serviceAddresses = stringArrayResource.getStringArray(R.array.service_array);
        partsAddresses = stringArrayResource.getStringArray(R.array.parts_array);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.maps);
        mapFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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.
        }
        mMap.setMyLocationEnabled(true);
    }

    public void render_Map(String[] addresses,LatLngBounds.Builder builder)
    {
        //mMap.clear();
        geocoder = new Geocoder(getActivity());
        for (int i = 0; i < 5; i++) {
            try {
                addressList = geocoder.getFromLocationName(addresses[i], 1);
            } catch (IOException e) {
                e.printStackTrace();
            }
            address = addressList.get(0);
            latLng = new LatLng(address.getLatitude(), address.getLongitude());
            marker = mMap.addMarker(new MarkerOptions().position(latLng).title(addresses[i]));
            builder.include(marker.getPosition());
        }

        bounds = builder.build();
        int padding = 0;
        cu = CameraUpdateFactory.newLatLngBounds(bounds, padding);
        mMap.animateCamera(cu);
    }
    @Override
    public void onClick(View view) {
        switch(view.getId()) {
            case R.id.btn_showroom:

            //new ShowProgressBar().execute("abc",null,null);

                LatLngBounds.Builder builder1 = new LatLngBounds.Builder();
                render_Map(showroomAddresses,builder1);
                flag = true;
             //   dialog.cancel();
                break;

            case R.id.btn_service:

                LatLngBounds.Builder builder2 = new LatLngBounds.Builder();
                render_Map(serviceAddresses,builder2);
                break;

            case R.id.btn_parts:

                LatLngBounds.Builder builder3 = new LatLngBounds.Builder();
                render_Map(partsAddresses,builder3);
                break;

            case R.id.btn_gas:

                Toast.makeText(getActivity(),getString(R.string.in_progress_text), Toast.LENGTH_SHORT).show();
                break;

            case R.id.btn_atm:

                Toast.makeText(getActivity(),getString(R.string.in_progress_text), Toast.LENGTH_SHORT).show();
                break;

            case R.id.btn_search:

                searchQueryString = searchQuery.getText().toString();
                List<Address> addressList1 = null;

                if(searchQueryString != null && !searchQueryString.equals(""))
                {
                    geocoder = new Geocoder(getContext());
                    try {
                        addressList1 = geocoder.getFromLocationName(searchQueryString, 1);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                    address = addressList1.get(0);
                    latLng = new LatLng(address.getLatitude(), address.getLongitude());
                    mMap.addMarker(new MarkerOptions().position(latLng).title(searchQueryString));
                    mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
                }
                else
                    Toast.makeText(getActivity(),getString(R.string.missing_search_query_error_message), Toast.LENGTH_SHORT).show();
                break;

        }
    }


    private class ShowProgressBar extends AsyncTask<String, Void, Void> {

        @Override
        protected void onPreExecute() {
            dialog = ProgressDialog.show(getActivity(), "",
                    "Loading. Please wait...", true);
        }

        @Override
        protected Void doInBackground(String... strings) {

        while (!flag == true)
        {
        }
            return null;
        }

        @Override

        protected void onPostExecute(Void aVoid) {
            super.onPostExecute(aVoid);
            dialog.dismiss();

        }
    }
}

Error Message: Error:(110, 180) error: incompatible types: LocatorsFragment cannot be converted to Context

Answer 1

您正在提供 this 而不是 getActivity()。在 onMapReady() 中正确如下:

@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;
    if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), 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.
    }
    mMap.setMyLocationEnabled(true);
}