如何为Android构建RSS阅读器？
我是android新手，我正在尝试为android构建RSS阅读器。我已经构建了所有的类和XML文件，但是没有提供所需的输出。这只是在传达信息如何为Android构建RSS阅读器？,android,rss-reader,Android,Rss Reader,我是android新手，我正在尝试为android构建RSS阅读器。我已经构建了所有的类和XML文件，但是没有提供所需的输出。这只是在传达信息 没有可用的RSS源 请有人建议我该怎么做 下面是我从教程中获取并试图操作的代码- public final String RSSFEEDOFCHOICE = "http://blog.01synergy.com/feed/"; public final String tag = "RSSReader"; private RSSFeed feed = n
没有可用的RSS源public final String RSSFEEDOFCHOICE = "http://blog.01synergy.com/feed/";
public final String tag = "RSSReader";
private RSSFeed feed = null;
/** Called when the activity is first created. */
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
// go get our feed!
feed = getFeed(RSSFEEDOFCHOICE);
// display UI
UpdateDisplay();
}
private RSSFeed getFeed(String urlToRssFeed)
{
try
{
// setup the url
URL url = new URL(urlToRssFeed);
// create the factory
SAXParserFactory factory = SAXParserFactory.newInstance();
// create a parser
SAXParser parser = factory.newSAXParser();
// create the reader (scanner)
XMLReader xmlreader = parser.getXMLReader();
// instantiate our handler
RSSHandler theRssHandler = new RSSHandler();
// assign our handler
xmlreader.setContentHandler(theRssHandler);
// get our data via the url class
InputSource is = new InputSource(url.openStream());
// perform the synchronous parse
xmlreader.parse(is);
// get the results - should be a fully populated RSSFeed instance, or null on error
return theRssHandler.getFeed();
}
catch (Exception ee)
{
// if we have a problem, simply return null
return null;
}
}
public boolean onCreateOptionsMenu(Menu menu)
{
super.onCreateOptionsMenu(menu);
menu.add(0,0,0, "Choose RSS Feed");
menu.add(0,1,0, "Refresh");
Log.i(tag,"onCreateOptionsMenu");
return true;
}
public boolean onOptionsItemSelected(Menu item){
switch (((View) item).getId()) {
case 0:
Log.i(tag,"Set RSS Feed");
return true;
case 1:
Log.i(tag,"Refreshing RSS Feed");
return true;
}
return false;
}
private void UpdateDisplay()
{
TextView feedtitle = (TextView) findViewById(R.id.feedtitle);
TextView feedpubdate = (TextView) findViewById(R.id.feedpubdate);
ListView itemlist = (ListView) findViewById(R.id.itemlist);
if (feed == null)
{
feedtitle.setText("No RSS Feed Available");
return;
}
feedtitle.setText(feed.getTitle());
feedpubdate.setText(feed.getPubDate());
ArrayAdapter<RSSItem> adapter = new ArrayAdapter<RSSItem>(this,android.R.layout.simple_list_item_1,feed.getAllItems());
itemlist.setAdapter(adapter);
itemlist.setOnItemClickListener(this);
itemlist.setSelection(0);
}
public void onItemClick(AdapterView parent, View v, int position, long id)
{
Log.i(tag,"item clicked! [" + feed.getItem(position).getTitle() + "]");
Intent itemintent = new Intent(this,ShowDescription.class);
Bundle b = new Bundle();
b.putString("title", feed.getItem(position).getTitle());
b.putString("description", feed.getItem(position).getDescription());
b.putString("link", feed.getItem(position).getLink());
b.putString("pubdate", feed.getItem(position).getPubDate());
itemintent.putExtra("android.intent.extra.INTENT", b);
startSubActivity(itemintent,0);
}
private void startSubActivity(Intent itemintent, int i) {
// TODO Auto-generated method stub
}
}
公共最终字符串RSSFEEDOFCHOICE=”http://blog.01synergy.com/feed/";
公共最终字符串tag=“RSSReader”；
专用RSSFeed feed=null；
/**在首次创建活动时调用*/
创建公共空间（捆绑冰柱）{
超级冰柱；
setContentView（R.layout.main）；
//去拿我们的饲料！
feed=getFeed（rssfeedof选择）；
//显示用户界面
UpdateDisplay（）；
}
私有RSSFeed getFeed（字符串urlToRssFeed）
{
尝试
{
//设置url
URL=新URL（urlToRssFeed）；
//创建工厂
SAXParserFactory=SAXParserFactory.newInstance（）；
//创建解析器
SAXParser parser=factory.newSAXParser（）；
//创建读卡器（扫描仪）
XMLReader=parser.getXMLReader（）；
//实例化我们的处理程序
RSSHandler-theRssHandler=新的RSSHandler（）；
//指派我们的处理人
setContentHandler（ThersHandler）；
//通过url类获取我们的数据
InputSource is=新的InputSource（url.openStream（））；
//执行同步解析
parse（is）；
//获取结果-应为完全填充的RSSFeed实例，或错误时为null
返回theRssHandler.getFeed（）；
}
捕获（异常ee）
{
//如果有问题，只需返回null
返回null；
}
}
公共布尔onCreateOptions菜单（菜单）
{
super.onCreateOptions菜单（菜单）；
添加（0,0,0，“选择RSS提要”）；
添加（0,1,0，“刷新”）；
Log.i（标记“onCreateOptions菜单”）；
返回true；
}
公共布尔值OnOptionItemSelected（菜单项）{
开关（（（视图）项）.getId（））{
案例0：
Log.i（标签，“设置RSS提要”）；
返回true；
案例1：
Log.i（标签，“刷新RSS提要”）；
返回true；
}
返回false；
}
私有void UpdateDisplay（）
{
TextView feedtitle=（TextView）findViewById（R.id.feedtitle）；
TextView feedpubdate=（TextView）findViewById（R.id.feedpubdate）；
ListView itemlist=（ListView）findViewById（R.id.itemlist）；
if（feed==null）
{
feedtitle.setText（“没有可用的RSS源”）；
返回；
}
feedtitle.setText（feed.getTitle（））；
feedpubdate.setText（feed.getPubDate（））；
ArrayAdapter=newArrayAdapter（这是android.R.layout.simple_list_item_1，feed.getAllItems（））；
itemlist.setAdapter（适配器）；
itemlist.setOnItemClickListener（此）；
itemlist.setSelection（0）；
}
public void onItemClick（AdapterView父视图、视图v、整型位置、长id）
{
Log.i（标记“单击的项”[“+feed.getItem（position.getTitle（）+”]）；
Intent itemintent=新的Intent（这个，showsdescription.class）；
Bundle b=新Bundle（）；
b、 putString（“title”，feed.getItem（position.getTitle（））；
b、 putString（“description”，feed.getItem（position.getDescription（））；
b、 putString（“link”，feed.getItem（position.getLink（））；
b、 putString（“pubdate”，feed.getItem（position.getPubDate（））；
itemintent.putExtra（“android.intent.extra.intent”，b）；
startSubActivity（itemintent，0）；
}
私有无效开始活动（意向项目意向，int i）{
//TODO自动生成的方法存根
}
}
似乎仍然有很多人对此感兴趣——因此，如果你正在寻找一款Android 3.0+系统，它具有片段/异步任务等，以及完整的应用程序代码，我已经再次更新了帖子，这是我第一次使用RSS阅读器，它没有那么动态，有样板代码，但对我来说效果很好 用法：
RssParser parser = new RssParser(feedUrl);
Log.i("LOG", "Description: " + parser.getItem(3).description); //4th item's description
package com.uncocoder.course.app.feed_reader;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class RssParser extends DefaultHandler {
private StringBuilder content;
private boolean inChannel;
private boolean inImage;
private boolean inItem;
private ArrayList<Item> items = new ArrayList<Item>();
private Channel channel = new Channel();
private Item lastItem;
public RssParser(String url) {
try {
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
URL sourceUrl = new URL(url);
xr.setContentHandler(this);
xr.parse(new InputSource(sourceUrl.openStream()));
}
catch (ParserConfigurationException e) {
e.printStackTrace();
}
catch (SAXException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
public class Item {
public String title;
public String description;
public String link;
public String category;
public String pubDate;
public String guid;
}
public class Channel {
public String title;
public String description;
public String link;
public String lastBuildDate;
public String generator;
public String imageUrl;
public String imageTitle;
public String imageLink;
public String imageWidth;
public String imageHeight;
public String imageDescription;
public String language;
public String copyright;
public String pubDate;
public String category;
public String ttl;
}
@Override
public void startDocument() throws SAXException {
Log.i("LOG", "StartDocument");
}
@Override
public void endDocument() throws SAXException {
Log.i("LOG", "EndDocument");
}
@Override
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = true;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = true;
}
if (localName.equalsIgnoreCase("item")) {
lastItem = new Item();
items.add(lastItem);
inItem = true;
}
content = new StringBuilder();
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = false;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = false;
}
if (localName.equalsIgnoreCase("item")) {
inItem = false;
}
if (localName.equalsIgnoreCase("title")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.title = content.toString();
} else if (inImage) {
channel.imageTitle = content.toString();
} else if (inChannel) {
channel.title = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("description")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.description = content.toString();
} else if (inImage) {
channel.imageDescription = content.toString();
} else if (inChannel) {
channel.description = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("link")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.link = content.toString();
} else if (inImage) {
channel.imageLink = content.toString();
} else if (inChannel) {
channel.link = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("category")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.category = content.toString();
} else if (inChannel) {
channel.category = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("pubDate")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.pubDate = content.toString();
} else if (inChannel) {
channel.pubDate = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("guid")) {
if (content == null) {
return;
}
lastItem.guid = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("url")) {
if (content == null) {
return;
}
channel.imageUrl = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("width")) {
if (content == null) {
return;
}
channel.imageWidth = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("height")) {
if (content == null) {
return;
}
channel.imageHeight = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("language")) {
if (content == null) {
return;
}
channel.language = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("copyright")) {
if (content == null) {
return;
}
channel.copyright = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("ttl")) {
if (content == null) {
return;
}
channel.ttl = content.toString();
content = null;
}
}
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (content == null) {
return;
}
content.append(ch, start, length);
}
public Item getItem(int index) {
return items.get(index);
}
}
RssParser parser = new RssParser(feedUrl);
Log.i("LOG", "Description: " + parser.getItem(3).description); //4th item's description
package com.uncocoder.course.app.feed_reader;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class RssParser extends DefaultHandler {
private StringBuilder content;
private boolean inChannel;
private boolean inImage;
private boolean inItem;
private ArrayList<Item> items = new ArrayList<Item>();
private Channel channel = new Channel();
private Item lastItem;
public RssParser(String url) {
try {
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
URL sourceUrl = new URL(url);
xr.setContentHandler(this);
xr.parse(new InputSource(sourceUrl.openStream()));
}
catch (ParserConfigurationException e) {
e.printStackTrace();
}
catch (SAXException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
public class Item {
public String title;
public String description;
public String link;
public String category;
public String pubDate;
public String guid;
}
public class Channel {
public String title;
public String description;
public String link;
public String lastBuildDate;
public String generator;
public String imageUrl;
public String imageTitle;
public String imageLink;
public String imageWidth;
public String imageHeight;
public String imageDescription;
public String language;
public String copyright;
public String pubDate;
public String category;
public String ttl;
}
@Override
public void startDocument() throws SAXException {
Log.i("LOG", "StartDocument");
}
@Override
public void endDocument() throws SAXException {
Log.i("LOG", "EndDocument");
}
@Override
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = true;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = true;
}
if (localName.equalsIgnoreCase("item")) {
lastItem = new Item();
items.add(lastItem);
inItem = true;
}
content = new StringBuilder();
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (localName.equalsIgnoreCase("image")) {
inImage = false;
}
if (localName.equalsIgnoreCase("channel")) {
inChannel = false;
}
if (localName.equalsIgnoreCase("item")) {
inItem = false;
}
if (localName.equalsIgnoreCase("title")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.title = content.toString();
} else if (inImage) {
channel.imageTitle = content.toString();
} else if (inChannel) {
channel.title = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("description")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.description = content.toString();
} else if (inImage) {
channel.imageDescription = content.toString();
} else if (inChannel) {
channel.description = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("link")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.link = content.toString();
} else if (inImage) {
channel.imageLink = content.toString();
} else if (inChannel) {
channel.link = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("category")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.category = content.toString();
} else if (inChannel) {
channel.category = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("pubDate")) {
if (content == null) {
return;
}
if (inItem) {
lastItem.pubDate = content.toString();
} else if (inChannel) {
channel.pubDate = content.toString();
}
content = null;
}
if (localName.equalsIgnoreCase("guid")) {
if (content == null) {
return;
}
lastItem.guid = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("url")) {
if (content == null) {
return;
}
channel.imageUrl = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("width")) {
if (content == null) {
return;
}
channel.imageWidth = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("height")) {
if (content == null) {
return;
}
channel.imageHeight = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("language")) {
if (content == null) {
return;
}
channel.language = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("copyright")) {
if (content == null) {
return;
}
channel.copyright = content.toString();
content = null;
}
if (localName.equalsIgnoreCase("ttl")) {
if (content == null) {
return;
}
channel.ttl = content.toString();
content = null;
}
}
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
if (content == null) {
return;
}
content.append(ch, start, length);
}
public Item getItem(int index) {
return items.get(index);
}
}
package com.uncocoder.course.app.feed\u阅读器；
导入java.io.IOException；
导入java.net.URL；
导入java.util.ArrayList；
导入javax.xml.parsers.parserConfiguration异常；
导入javax.xml.parsers.SAXParser；
导入javax.xml.parsers.SAXParserFactory；
导入org.xml.sax.Attributes；
导入org.xml.sax.InputSource；
导入org.xml.sax.SAXException；
导入org.xml.sax.XMLReader；
导入org.xml.sax.helpers.DefaultHandler；
导入android.util.Log；
公共类RssParser扩展了DefaultHandler{
私有内容；
通道中的私有布尔；
私有布尔图像；
私有布尔inItem；
private ArrayList items=new ArrayList（）；
专用通道=新通道（）；
私人物品；
公共RssParser（字符串url）{
试一试{
SAXParserFactory spf=SAXParserFactory.newInstance（）；
SAXParser sp=spf.newSAXParser（）；
XMLReader xr=sp.getXMLReader（）；
URL sourceUrl=新URL（URL）；
xr.setContentHandler（此）；
parse（新的InputSource（sourceUrl.openStream（））；
}
捕获（ParserConfiguration异常e）{
e、 printStackTrace（）；
}
捕获（SAXE异常）{
e、 printStackTrace（）；
}
捕获（IOE异常）{
e、 printStackTrace（）；
}
}
公共类项目{
公共字符串标题；
公共字符串描述；
公共字符串链接；
公共字符串类别；
公共字符串pubDate；
公共字符串guid；