如何将所有清除的数据添加到recyclerview

Question

我正在研究一个示例with listview，其中我想在后台线程上执行网络请求。在我的应用中，我正在使用a recyclerview。 Android Studio声明无法解析方法.clear和。addAll。这样做是不是我使用的是recyclerview而不是listview？还是其他的东西？

根据我的示例，这是我在MainActivity中拥有的内容：

package com.example.android.guardiannews;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;

import com.example.android.guardiannews.AdapterClass.NewsAdapter;
import com.example.android.guardiannews.AdapterModel.ItemsModel;
import com.example.android.guardiannews.Utils.QueryUtils;

import java.util.ArrayList;
import java.util.List;


public class MainActivity extends AppCompatActivity {

    /**
     * Tag for the log messages
     */
    public static final String LOG_TAG = MainActivity.class.getSimpleName();

    /**
     * URL to query the Guardian's API dataset for articles
     */
    private static final String GUARDIAN_REQUEST_URL =
            "http://content.guardianapis.com/search?from-date=2019-03-04&to-date=2019-03-04&order-by=newest&show-tags=contributor&show-fields=trailText,thumbnail&page-size=4&api-key=982f19d8-023e-4aa0-842c-ba1970ae9c46";

    /**
     * Adapter for the list of articles
     */
    private NewsAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        // Find a reference to the {@link RecyclerView} in the layout
        RecyclerView recyclerView = findViewById(R.id.recycler_view);

        // Create a new adapter that takes the list of articles as input
        mAdapter = new NewsAdapter(new ArrayList<ItemsModel>(), this);

        //Set the adapter
        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(MainActivity.this);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setAdapter(mAdapter);

        // Kick off an {@link ArticleAsyncTask} to perform the network request
        ArticleAsyncTask task = new ArticleAsyncTask();
        task.execute(GUARDIAN_REQUEST_URL);
    }

    /**
     * {@link AsyncTask} to perform the network request on a background thread, and then
     * update the UI with the first article in the response.
     */
    private class ArticleAsyncTask extends AsyncTask<String, Void, List<ItemsModel>> {

        /**
         * This method runs on a background thread and performs the network request.
         * We should not update the UI from a background thread, so we return a list of
         * {@link ItemsModel}s as the result.
         */
        @Override
        protected List<ItemsModel> doInBackground(String... urls) {
            // Don't perform the request if there are no URLs, or the first URL is null
            if (urls.length < 1 || urls[0] == null) {
                return null;
            }

            List<ItemsModel> result = QueryUtils.fetchArticleData(urls[0]);
            return result;
        }

        /**
         * This method runs on the main UI thread after the background work has been
         * completed. This method receives as input, the return value from the doInBackground()
         * method. First we clear out the adapter, to get rid of articles data from a previous
         * query. Then we update the adapter with the new list of articles,
         * which will trigger the ListView to re-populate its list items.
         */
        @Override
        protected void onPostExecute(List<ItemsModel> data) {
            // Clear the adapter of previous articles data
            mAdapter.clear();

            // If there is a valid list add them to the adapter's
            // data set. This will trigger the RecyclerView to update.
            if (data != null && !data.isEmpty()) {
                mAdapter.addAll(data);
            }
        }
    }
}