Question

我正在尝试实施此RSS阅读器：http://intel-software-academic-program.com/courses/mobile/android/IntelAcademic_AndroidEPITECH_05_Flux_RSS_FR.pdf

在我的片段上：

但我在这一行上收到错误：

adapter = new NewsAdapter(this, new ArrayList<News>());

NewsAdapter中的

＆＃34; NewsAdapter（Android.content.context，List）无法应用于（包，ArrayList）

Actualites.java：

import android.os.AsyncTask;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import org.xmlpull.v1.XmlPullParserException;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

public class Actualites extends android.support.v4.app.Fragment{
    AsyncTask<Void, Void, List> a = null;
    NewsAdapter adapter = null;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        View view = inflater.inflate(R.layout.activity_actualites, container, false);
        ListView list = (ListView) view.findViewById(R.id.newsList);
        adapter = new NewsAdapter(this, new ArrayList<News>());
        list.setAdapter(adapter);
        a = new AsyncTask<Void, Void, List>() {
            @Override
            protected List doInBackground(Void... params) {
                ArrayList<News> res = new ArrayList<News>();
                try {
                    URL url = new URL("http://feeds.lefigaro.fr/c/32266/f/438191/index.rss");
                    HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
                    RssParser parser = new RssParser();
                    try {
                        return parser.parse(urlConnection.getInputStream());
                    } catch (XmlPullParserException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
                return res;
            }

            @Override
            protected void onPostExecute(List result) {
                adapter.update(result);
            }
        };
        a.execute();
        return view;
    }
}

RssParser.java：

import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import android.util.Xml;

public class RssParser {
    private String readText(XmlPullParser parser) throws IOException, XmlPullParserException {
        String result = "";
        if (parser.next() == XmlPullParser.TEXT) {
            result = parser.getText();
            parser.nextTag();
        }
        return result;
    }
    private static final String ns = null;

    private void skip(XmlPullParser parser) throws XmlPullParserException, IOException {
        if (parser.getEventType() != XmlPullParser.START_TAG) {
            throw new IllegalStateException();
        }
        int depth = 1;
        while (depth != 0) {
            switch (parser.next()) {
                case XmlPullParser.END_TAG:
                    depth--;
                    break;
                case XmlPullParser.START_TAG:
                    depth++;
                    break;
            }
        }
    }

    public ArrayList<News> parse(InputStream in) throws XmlPullParserException, IOException {
        XmlPullParser parser = Xml.newPullParser();
        parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false);
        parser.setInput(in, null);
        parser.nextTag();
        ArrayList<News> entries = new ArrayList<News>();

        parser.require(XmlPullParser.START_TAG, ns, "rss");
        parser.nextTag();
        parser.require(XmlPullParser.START_TAG, ns, "channel");
        while (parser.next() != XmlPullParser.END_TAG) {
            if (parser.getEventType() != XmlPullParser.START_TAG) {
                continue;
            }
            String name = parser.getName();
            if (name.equals("item")) {
                String title = "";
                String content = "";
                while (parser.next() != XmlPullParser.END_TAG) {
                    if (parser.getEventType() != XmlPullParser.START_TAG) {
                        continue;
                    }
                    name = parser.getName();
                    if (name.equals("title")) {
                        title = readText(parser);
                    } else if (name.equals("description")) {
                        content = readText(parser);
                    } else
                        skip(parser);
                }
                entries.add(new News(title, content));
            }  else
                skip(parser);
        }
        return entries;
    }
}

NewsAdapter.java：

import java.util.List;
import android.content.Context;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

public class NewsAdapter extends BaseAdapter {
    List<News> news;
    Context context;

    public NewsAdapter(Context context, List<News> news) {
        this.news = news;
        this.context = context;
    }

    public void update(List<News> news) {
        this.news = news;
        notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        return news.size();
    }

    @Override
    public Object getItem(int arg0) {
        return news.get(arg0);
    }

    @Override
    public long getItemId(int arg0) {
        return arg0;
    }

    @Override
    public View getView(int arg0, View arg1, ViewGroup arg2) {
        LayoutInflater li = LayoutInflater.from(context);
        View v = li.inflate(android.R.layout.two_line_list_item, null);
        TextView tv1 = (TextView)v.findViewById(android.R.id.text1);
        TextView tv2 = (TextView)v.findViewById(android.R.id.text2);
        News n = (News)getItem(arg0);
        tv1.setText(n.getTitle());
        String content = Html.fromHtml(n.getContent()).toString().replace((char) 65532, (char) 32).trim();
        tv2.setText(content);
        return v;
    }
}

News.java：

public class News {
    private String title;
    private String content;

    public News(String title, String content) {
        this.title = title;
        this.content = content;
    }

    public String getTitle() {
        return (title);
    }

    public String getContent() {
        return (content);
    }
}

任何人都可以帮助我？

Answer 1

如果要下载xml或json文件，仍需要在Android清单文件中写入网络权限。（外部申请标签）

＆LT; uses-permission android：name =＆＃34; android.permission.INTERNET＆＃34; /＆GT;

Android Studio上的RSS阅读器

1 个答案: