如何在选项卡式活动中实现自定义列表视图适配器？

Question

我正在尝试在youtube视频播放应用的标签式活动中实现自定义列表视图。我无法在片段java类中调用自定义listview适配器。我试图将getActivity（）传递给自定义适配器，但应用程序崩溃了。如果有人知道解决方案，请帮助我。

java类如下：

HomeFragment.java

package layout;

import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import java.util.ArrayList;
import java.util.List;

import in.testapp.app1.R;

    public class HomeFragment extends Fragment {
        static class Adapter extends FragmentPagerAdapter {
            private final List<Fragment> mFragmentList = new ArrayList();
            private final List<String> mFragmentTitleList = new ArrayList();

            public Adapter(FragmentManager manager) {
                super(manager);
            }

            public Fragment getItem(int position) {
                return (Fragment) this.mFragmentList.get(position);
            }

            public int getCount() {
                return this.mFragmentList.size();
            }

            public void addFragment(Fragment fragment, String title) {
                this.mFragmentList.add(fragment);
                this.mFragmentTitleList.add(title);
            }

            public CharSequence getPageTitle(int position) {
                return (CharSequence) this.mFragmentTitleList.get(position);
            }
        }

        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setRetainInstance(true);
        }

        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            View view = inflater.inflate(R.layout.fragment_home, container, false);
            ViewPager viewPager = (ViewPager) view.findViewById(R.id.viewpager);
            setupViewPager(viewPager);
            ((TabLayout) view.findViewById(R.id.tablayout)).setupWithViewPager(viewPager);
            return view;
        }

        private void setupViewPager(ViewPager viewPager) {
            Adapter adapter = new Adapter(getChildFragmentManager());
            adapter.addFragment(new YouTubeFragment(), "Tab 1");
            adapter.addFragment(new SecondFragment(), "Tab 2");
            viewPager.setAdapter(adapter);
        }
    }

YouTubeFragment.java

package layout;

import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings.PluginState;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.Toast;

import com.android.volley.DefaultRetryPolicy;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.RetryPolicy;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;

import in.testapp.app1.AppUtils;
import in.testapp.app1.ChannelActivity;
import in.testapp.app1.CustomListAdapter;
import in.testapp.app1.R;
import in.testapp.app1.VideoDetails;

public class YouTubeFragment extends Fragment {
    String TAG="MainActivity2";
    ListView lvVideo;
    ArrayList<VideoDetails> videoDetailsArrayList;
    CustomListAdapter customListAdapter;
    //{youtube_api_key} is replaced by actual key
    String URL="https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UC5Eg6bkwsdCd-ZlcB3nt1dg&maxResults=25&key={youtube_api_key}";

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_you_tube, container, false);
        lvVideo=(ListView)view.findViewById(R.id.videoList);
        videoDetailsArrayList=new ArrayList<>();

        //App crashes here in the beolw line
        customListAdapter=new CustomListAdapter(getActivity(),videoDetailsArrayList);
        //App crashes here in the above line

        showVideo();
        return view;
    }
    private void showVideo() {
        RequestQueue requestQueue= Volley.newRequestQueue(getContext());
        StringRequest stringRequest=new StringRequest(Request.Method.GET, URL, new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                try {
                    JSONObject jsonObject=new JSONObject(response);
                    JSONArray jsonArray=jsonObject.getJSONArray("items");
                    for(int i=1;i<jsonArray.length();i++){
                        JSONObject jsonObject1 = jsonArray.getJSONObject(i);
                        JSONObject jsonVideoId=jsonObject1.getJSONObject("id");
                        JSONObject jsonsnippet= jsonObject1.getJSONObject("snippet");
                        JSONObject jsonObjectdefault = jsonsnippet.getJSONObject("thumbnails").getJSONObject("medium");
                        VideoDetails videoDetails=new VideoDetails();

                        String videoid=jsonVideoId.getString("videoId");

                        Log.e(TAG," New Video Id" +videoid);
                        videoDetails.setURL(jsonObjectdefault.getString("url"));
                        videoDetails.setVideoName(jsonsnippet.getString("title"));
                        videoDetails.setVideoDesc(jsonsnippet.getString("description"));
                        videoDetails.setVideoId(videoid);

                        videoDetailsArrayList.add(videoDetails);
                    }
                    lvVideo.setAdapter(customListAdapter);
                    customListAdapter.notifyDataSetChanged();
                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                error.printStackTrace();
            }
        });
        int socketTimeout = 30000;
        RetryPolicy policy = new DefaultRetryPolicy(socketTimeout, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
        stringRequest.setRetryPolicy(policy);
        requestQueue.add(stringRequest);

    }
}

CustomListAdapter.java

package in.testapp.app1;
import android.app.Activity;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.NetworkImageView;
import java.util.ArrayList;
public class CustomListAdapter extends BaseAdapter {
    Activity activity;
    ImageLoader imageLoader = AppController.getInstance().getImageLoader();
    private LayoutInflater inflater;
    ArrayList<VideoDetails> singletons;
    public CustomListAdapter(Activity activity, ArrayList<VideoDetails> singletons) {
        this.activity = activity;
        this.singletons = singletons;
    }
    public int getCount() {
        return this.singletons.size();
    }
    public Object getItem(int i) {
        return this.singletons.get(i);
    }
    public long getItemId(int i) {
        return (long) i;
    }
    public View getView(int i, View convertView, ViewGroup viewGroup) {
        if (this.inflater == null) {
            this.inflater = (LayoutInflater) this.activity.getLayoutInflater();
                   // getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        }
        if (convertView == null) {
            convertView = this.inflater.inflate(R.layout.videolist, null);
        }
        if (this.imageLoader == null) {
            this.imageLoader = AppController.getInstance().getImageLoader();
        }
        NetworkImageView networkImageView = (NetworkImageView) convertView.findViewById(R.id.video_image);
        final TextView imgtitle = (TextView) convertView.findViewById(R.id.video_title);
        final TextView imgdesc = (TextView) convertView.findViewById(R.id.video_descriptio);
        final TextView tvURL=(TextView)convertView.findViewById(R.id.tv_url);
        final  TextView tvVideoID=(TextView)convertView.findViewById(R.id.tv_videoId);
       ((LinearLayout) convertView.findViewById(R.id.asser)).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent=new Intent(view.getContext(), VideoActivity.class);
                intent.putExtra("videoId",tvVideoID.getText().toString());
                view.getContext().startActivity(intent);
            }
        });
        VideoDetails singleton = (VideoDetails) this.singletons.get(i);
        networkImageView.setImageUrl(singleton.getURL(), this.imageLoader);
        tvVideoID.setText(singleton.getVideoId());
        imgtitle.setText(singleton.getVideoName());
        imgdesc.setText(singleton.getVideoDesc());
        return convertView;
    }
}

VideoDeatils.java

package in.testapp.app1;

public class VideoDetails {
    String VideoName;
    String VideoDesc;
    String URL;
    String VideoId;


public void setVideoName(String VideoName){
    this.VideoName=VideoName;
}

public String getVideoName(){
    return VideoName;
}

public void setVideoDesc(String VideoDesc){
    this.VideoDesc=VideoDesc;
}

public String getVideoDesc(){
    return VideoDesc;
}

public void setURL(String URL){
    this.URL=URL;
}

public String getURL(){
    return URL;
}

public void setVideoId(String VideoId){
    this.VideoId=VideoId;
}
public String getVideoId(){
    return VideoId;
}

}