如何在我的代码中使用分页，我的应用程序在滚动recyclerview时崩溃了？

Question

我试图在我的应用程序中显示JSON响应，在我的应用程序中显示图标和标题，我使用了recyclerview在cardview上垂直列出项目。但我的应用程序崩溃，而我向下滚动，我谷歌一些sollution它说使用分页。我从不使用分页。帮助我解决问题

 class ListSourceViewHolder extends RecyclerView.ViewHolder implements 
    View.OnClickListener
    {
    ItemClickListener itemClickListener;
    TextView source_title;
    CircleImageView source_image;
    public ListSourceViewHolder(View itemView) {
        super(itemView);
        source_image=(CircleImageView)itemView.findViewById(R.id.source_image);
        source_title=(TextView) itemView.findViewById(R.id.source_name);
        itemView.setOnClickListener(this);
    }

    public void setItemClickListener(ItemClickListener itemClickListener) {
        this.itemClickListener = itemClickListener;
    }

    @Override
    public void onClick(View v) {
        itemClickListener.onClick(v,getAdapterPosition(),false);
    }
}
     public class ListSourceAdapter 
     extendsRecyclerView.Adapter<ListSourceViewHolder> {

    private Context context;
    private WebSite webSite;
    private IconBetterIdeaService mService;

    public ListSourceAdapter(Context context, WebSite webSite) {
        this.context = context;
        this.webSite = webSite;
        mService= Common.getIconService();
    }

    @Override
    public ListSourceViewHolder onCreateViewHolder(ViewGroup parent, int 
    viewType) {
        LayoutInflater inflater=LayoutInflater.from(parent.getContext());
        View view=inflater.inflate(R.layout.source_layout,parent,false);
        return new ListSourceViewHolder(view);
    }

    @Override
    public void onBindViewHolder(final ListSourceViewHolder holder, final int 
    position) {
     StringBuilder iconBetterAPI=new StringBuilder("https://icons.better-
    idea.org/allicons.json?url=");
        iconBetterAPI.append(webSite.getSources().get(position).getUrl());
        mService.getIconUrl(iconBetterAPI.toString()).enqueue(new 
    Callback<IconBetterIdea>() {
            @Override
            public void onResponse(Call<IconBetterIdea> call, 
    Response<IconBetterIdea> response) {

    if (response.body().getIcons().size() > 0)
     {
           Picasso.with(context).load(response.body().getIcons().get(0).getUrl()).into(holder.source_image);

                    }
                }
            @Override
            public void onFailure(Call<IconBetterIdea> call, Throwable t) {

            }
        });

    holder.source_title.setText(webSite.getSources().get(position).getName());
        holder.setItemClickListener(new ItemClickListener() {
            @Override
            public void onClick(View view, int position, boolean isLongClick) {
                Intent intent=new Intent(context, ListNews.class);
                intent.putExtra("source", 
                webSite.getSources().get(position).getId());
                intent.putExtra("sortBy", 

            webSite.getSources().get(position).getSortBysAvailable().get(0));
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                context.startActivity(intent);

            }
        });
    }

     @Override
    public int getItemCount() {
        return webSite.getSources().size();
    }
    }


//Here is my mainActivity
package pay4free.in.primenews;

import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;

import com.google.gson.Gson;

import dmax.dialog.SpotsDialog;
import io.paperdb.Paper;
import pay4free.in.primenews.Adapter.ListSourceAdapter;
import pay4free.in.primenews.Common.Common;
import pay4free.in.primenews.Interface.NewsService;
import pay4free.in.primenews.Model.WebSite;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;

public class MainActivity extends AppCompatActivity {
RecyclerView listWebsite;
    RecyclerView.LayoutManager layoutManager;
    NewsService mService;
    ListSourceAdapter adapter;
    SpotsDialog Dialog;
    SwipeRefreshLayout swipeRefreshLayout;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Paper.init(this);
        mService= Common.getNewsService();
      swipeRefreshLayout=(SwipeRefreshLayout)findViewById(R.id.swipe);
        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                loadWebsiteSource(true);
            }
        });
        listWebsite=(RecyclerView)findViewById(R.id.list_source);
        listWebsite.setHasFixedSize(false);
        layoutManager=new LinearLayoutManager(this);
        listWebsite.setLayoutManager(layoutManager);

        Dialog=new SpotsDialog(this);
        loadWebsiteSource(false);

    }

    private void loadWebsiteSource(boolean isRefreshed) {
if(!isRefreshed)
{
    String cache =Paper.book().read("cache");
    if(cache!=null&&!cache.isEmpty())
    {
        WebSite webSite=new Gson().fromJson(cache,WebSite.class);
        adapter=new ListSourceAdapter(getBaseContext(),webSite);
        adapter.notifyDataSetChanged();
        listWebsite.setAdapter(adapter);
    }
    else
    {
        Dialog.show();
        mService.getSources().enqueue(new Callback<WebSite>() {
            @Override
            public void onResponse(Call<WebSite> call, Response<WebSite> response) {
                adapter=new ListSourceAdapter(getBaseContext(),response.body());
                adapter.notifyDataSetChanged();
                listWebsite.setAdapter(adapter);
                Paper.book().write("cache",new Gson().toJson(response.body()));
            }

            @Override
            public void onFailure(Call<WebSite> call, Throwable t) {

            }
        });
    }
}
else
{
    Dialog.show();
    mService.getSources().enqueue(new Callback<WebSite>() {
        @Override
        public void onResponse(Call<WebSite> call, Response<WebSite> response) {
            adapter=new ListSourceAdapter(getBaseContext(),response.body());
            adapter.notifyDataSetChanged();
            listWebsite.setAdapter(adapter);

            Paper.book().write("cache",new Gson().toJson(response.body()));
            swipeRefreshLayout.setRefreshing(false);
        }

        @Override
        public void onFailure(Call<WebSite> call, Throwable t) {

        }
    });
}
    }

    @Override
    public void onBackPressed() {
        super.onBackPressed();
    }
}

帮助我，当我向下滚动到底部时，我的应用程序崩溃了。

Answer 1

每次都在创建适配器。只创建一次适配器并更新它。 删除这些行

adapter=new ListSourceAdapter(getBaseContext(),response.body());
adapter.notifyDataSetChanged();
listWebsite.setAdapter(adapter);

创建一个方法来更新适配器中的数据。

adapter.yourMethodToUpdate(response.body());
adapter.notifyDataSetChanged();