通过服务器获取xml文件并解析

由于数据在服务器上
所以使用Tomcat作为服务器
http://localhost:8080能连接上说明启动成功了
把xml文件放在E:\Tomcat9\webapps\ROOT下
xml代码如下

由于数据在服务上 所以要开启线程发起网络请求获取数据

 private void initData() {

        //开启线程发起网络请求
        new Thread() {
            @Override
            public void run() {
                super.run();
                String path = "http://这里写上你的电脑的ip地址:8080/app.xml";
                try {
                    //要访问的路径
                    URL url = new URL(path);
                    //用于发送或接受数据
                    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                    //发送get请求
                    conn.setRequestMethod("GET");
                    //请求超时时间
                    conn.setConnectTimeout(5000);
                    //服务器返回的状态码
                    int code = conn.getResponseCode();
                    //说明请求成功
                    if (code == 200) {
                        //获取服务器返回的数据
                        InputStream in = conn.getInputStream();
                        //创建一个方法去解析xml文件的逻辑
                        appsList = ParserXml.parserXml(in);
			
			//把数据展示在Listview上
                        runOnUiThread(new Runnable() {
                            @Override
                            public void run() {
                                lv_list.setAdapter(new MyAdapter(MainActivity.this));
                            }
                        });
                    }
                } catch (MalformedURLException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }.start();
    }

解析xml文件的逻辑，创建一个集合类，里面放的是Apps的属性

public class ParserXml {

    //用于解析xml数据的方法
    public static List parserXml(InputStream in) {
        List appsList=null;
        Apps apps=null;
        
        //获取xml解析器
        XmlPullParser Parser = Xml.newPullParser();
        try {
            //要解析的内容
            Parser.setInput(in, "utf-8");
            //获取解析的事件类型
            int type = Parser.getEventType();
            //不等于文档的结尾就不停的向下解析
            while (type != XmlPullParser.END_DOCUMENT) {
                //判断是开始节点还是结束节点
                switch (type) {
                    //开始节点
                    case XmlPullParser.START_TAG:
                        if ("apps".equals(Parser.getName())) {
                            appsList = new ArrayList<>();
                        } else if ("app".equals(Parser.getName())) {
                            apps = new Apps();
                        } else if ("id".equals(Parser.getName())) {
                            apps.setId(Parser.nextText());
                        } else if ("title".equals(Parser.getName())) {
                            apps.setTitle(Parser.nextText());
                        } else if ("content".equals(Parser.getName())) {
                            apps.setContent(Parser.nextText());
                        } else if ("image".equals(Parser.getName())) {
                            apps.setImage(Parser.nextText());
                        } else if ("comment".equals(Parser.getName())) {
                            apps.setComment(Parser.nextText());
                        }
                        break;
                    //结束节点
                    case XmlPullParser.END_TAG:
                        if ("app".equals(Parser.getName())) {
                            appsList.add(apps);
                        }
                        break;
                }
                type = Parser.next();
            }
        } catch (XmlPullParserException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return appsList;
    }
}

要把数据展示出来就需要一个ListView或RecyclerView

新建一个类继承 BaseAdapter，这里用到了第三方库smartimageview，用于设置图片的url

    public class MyAdapter extends BaseAdapter {
        private Context mcontext;

        MyAdapter(Context context) {
            this.mcontext = context;
        }

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

        @Override
        public Object getItem(int position) {
            return null;
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder vh;
            if (convertView == null) {
                view = View.inflate(mcontext, R.layout.list_apps, null);
                vh = new ViewHolder();
                vh.iv_icon = view.findViewById(R.id.iv_icon);
                vh.tv_title = view.findViewById(R.id.tv_title);
                vh.tv_content = view.findViewById(R.id.tv_content);
                vh.tv_comment = view.findViewById(R.id.tv_comment);
                view.setTag(vh);
            } else {
                view = convertView;
                vh = (ViewHolder) view.getTag();
            }
	   
	    //设置图片
            String uriImage = appsList.get(position).getImage();
            vh.iv_icon.setImageUrl(uriImage);
            //设置标题
            vh.tv_title.setText(appsList.get(position).getTitle());
            //设置内容
            vh.tv_content.setText(appsList.get(position).getContent());
            //获取id,根据id去判断访问量的多少
            int id = Integer.parseInt(appsList.get(position).getId());
            switch (id) {
                case 1:
                    vh.tv_comment.setText(appsList.get(position).getComment());
                    break;
                case 2:
                    vh.tv_comment.setText(appsList.get(position).getComment());
                    break;
                case 3:
                    vh.tv_comment.setText(appsList.get(position).getComment());
                    break;
            }
            return view;
        }

        class ViewHolder {
            com.loopj.android.image.SmartImageView iv_icon;
            TextView tv_title;
            TextView tv_content;
            TextView tv_comment;
        }
    }