Question

我正在使用底部导航的片段中使用mapbox，当我退出并恢复应用程序时，或者当我快速更改选项卡时，应用程序崩溃。这是我得到的错误

10-07 22:20:36.046 21867-21886/com.dropexpress.driver.dropexpressdriver E/Mbgl-FileSource: Failed to read the storage key: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.os.Bundle.getBoolean(java.lang.String, boolean)' on a null object reference at com.mapbox.mapboxsdk.storage.FileSource.getCachePath(FileSource.java:88) at com.mapbox.mapboxsdk.storage.FileSource$FileDirsPathsTask.doInBackground(FileSource.java:165) at com.mapbox.mapboxsdk.storage.FileSource$FileDirsPathsTask.doInBackground(FileSource.java:155) at android.os.AsyncTask$2.call(AsyncTask.java:304) at java.util.concurrent.FutureTask.run(FutureTask.java:237) at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607) at java.lang.Thread.run(Thread.java:761) 当我退出应用并恢复运行，或者当我快速更改选项卡时，使用底部导航时，以下代码始终失败。

复制步骤

这是我的片段代码

package com.dropexpress.driver.dropexpressdriver.fragments;
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import com.dropexpress.driver.dropexpressdriver.R;
import com.mapbox.mapboxsdk.Mapbox;
import com.mapbox.mapboxsdk.maps.MapView;
    public class HomeFragment extends Fragment {
    private MapView mapView;
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    private String mParam1;
    private String mParam2;

    private OnFragmentInteractionListener mListener;

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

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment HomeFragment.
     */
    // TODO: Rename and change types and number of parameters
    public static HomeFragment newInstance(String param1, String param2) {
        HomeFragment fragment = new HomeFragment();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment

        View view = inflater.inflate(R.layout.fragment_home, container, false);
        Mapbox.getInstance(requireActivity(), "pk.eyJ1Ijoic3ludGF4bHRkIiwiYSI6ImNqaDJxNnhzbDAwNnMyeHF3dGlqODZsYjcifQ.pcz6BWpzCHeZ6hQg4AH9ww");
        mapView = (MapView) view.findViewById(R.id.mapView);
        mapView.onCreate(savedInstanceState);

        return  view;
    }

    // TODO: Rename method, update argument and hook method into UI event
    public void onButtonPressed(Uri uri) {
        if (mListener != null) {
            mListener.onFragmentInteraction(uri);
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }

    /**
     * This interface must be implemented by activities that contain this
     * fragment to allow an interaction in this fragment to be communicated
     * to the activity and potentially other fragments contained in that
     * activity.
     * <p>
     * See the Android Training lesson <a href=
     * "http://developer.android.com/training/basics/fragments/communicating.html"
     * >Communicating with Other Fragments</a> for more information.
     */
    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        void onFragmentInteraction(Uri uri);
    }
    @Override
    public void onResume() {
        super.onResume();
        mapView.onResume();
    }

    @Override
    public void onPause() {
        super.onPause();
        mapView.onPause();
    }

    @Override
    public void onStop() {
        super.onStop();
        mapView.onStop();
    }

    @Override
    public void onLowMemory() {
        super.onLowMemory();
        mapView.onLowMemory();
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        mapView.onSaveInstanceState(outState);
    }

}

Android版本： 5.0 + 设备型号：摩托罗拉g5 Mapbox SDK版本： 6.5.0

Answer 1

在扩大布局之前，先放置Mapbox.getInstance。

  Mapbox.getInstance(requireActivity(),"Your Map Key");
  View view = inflater.inflate(R.layout.fragment_home, container, false);
  mapView = (MapView) view.findViewById(R.id.mapView);
  mapView.onCreate(savedInstanceState);

希望对您有帮助。

Answer 2

我在github中打开了此问题，您可以在此处查看他们的回复

https://github.com/mapbox/mapbox-gl-native/issues/13044#issuecomment-427861016

这是他们的回应：

我发现提供的代码有2个问题：

您没有呼叫MapView#onDestroy，必须从您片段的#onDestroyView进行呼叫。应该从片段的MapView#onCreate而不是#onViewCreated调用#onCreateView。

我应用了更改并成功了！

如何在片段中成功实现android mapbox android sdk

复制步骤

2 个答案: