新闻客户端

运行效果图

1、新闻客户端程序对应的布局文件（activity_main.xml）

            这个界面包含了提示用户数据正在加载中的ProgressBar、TextView以及展示新闻信息的ListView

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="cn.edu.bzu.anew.MainActivity">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <LinearLayout
            android:id="@+id/loading"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:gravity="center"
            android:orientation="vertical"
            android:visibility="invisible">
            <ProgressBar
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="正在加载信息..." />
        </LinearLayout>
        <ListView
            android:id="@+id/lv_news"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
    </FrameLayout>
</RelativeLayout>

2、创建ListView Item布局文件（news_item.xml）

   布局文件使用了自定义控件SmartImageView和分别用于展示新闻标题、新闻内容以及新闻评论数的TextView。android:scaleType属性是ImageView中的，用来控制图片来匹配View的大小的。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="65dp">
    <com.loopj.android.image.SmartImageView
        android:id="@+id/siv_icon"
        android:layout_width="80dp"
        android:layout_height="60dp"
        android:scaleType="centerCrop"
        android:src="@mipmap/ic_launcher"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"></com.loopj.android.image.SmartImageView>
    <TextView
        android:id="@+id/tv_title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="10dp"
        android:layout_toRightOf="@id/siv_icon"
        android:ellipsize="end"
        android:maxLength="20"
        android:singleLine="true"
        android:text="我是标题"
        android:textColor="#000000"
        android:textSize="18sp" />

    <TextView
        android:id="@+id/tv_description"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/tv_title"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="5dp"
        android:layout_toRightOf="@id/siv_icon"
        android:ellipsize="end"
        android:maxLength="16"
        android:maxLines="1"
        android:text="我是描述"
        android:textColor="#99000000"
        android:textSize="14sp" />

    <TextView
        android:id="@+id/tv_type"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_marginBottom="5dp"
        android:layout_marginRight="10dp"
        android:text="评论"
        android:textColor="#99000000"
        android:textSize="12sp" />

</RelativeLayout>

3、创建实体类NewsInfo.java

package cn.edu.bzu.anew.entity;

/**
 * Created by Administrator on 2017/5/18.
 */

public class NewsInfo {
    private  String icon;
    private  String title;
    private  String description;
    private  int type;
    private  long comment;

    public NewsInfo(String icon, String title, String description, int type, long comment) {
        this.icon = icon;
        this.title = title;
        this.description = description;
        this.type = type;
        this.comment = comment;
    }

    public String getIcon() {
        return icon;
    }

    public void setIcon(String icon) {
        this.icon = icon;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public long getComment() {
        return comment;
    }

    public void setComment(long comment) {
        this.comment = comment;
    }
}

4、创建适配器NewsAdapter.java继承与ArrayAdapter

package cn.edu.bzu.anew.adapter;


import android.content.Context;
import android.support.annotation.NonNull;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import com.loopj.android.image.SmartImageView;

import java.util.List;

import cn.edu.bzu.anew.R;
import cn.edu.bzu.anew.entity.NewsInfo;


public class NewsAdapter extends ArrayAdapter<NewsInfo>{
    public NewsAdapter(Context context, List<NewsInfo> objects) {
        super(context, R.layout.news_item, objects);

    }

    @NonNull
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        NewsInfo newsinfo= getItem(position);//传递position，获取当前位置对应的newsinfo新闻信息
        View view=null;
        viewHolder viewHolder;
        if(convertView==null){ //判断convertView中是否加载了布局，有没有缓存。为空说明没有缓存
            view=LayoutInflater.from(getContext()).inflate(R.layout.news_item,null);
            viewHolder=new viewHolder();
            viewHolder.siv= (SmartImageView) view.findViewById(R.id.siv_icon);
            viewHolder.tv_title= (TextView) view.findViewById(R.id.tv_title);
            viewHolder.tv_description= (TextView) view.findViewById(R.id.tv_description);
            viewHolder.tv_type= (TextView) view.findViewById(R.id.tv_type);
            view.setTag(viewHolder); //保存
        }else{
            view=convertView;
            viewHolder=(viewHolder) view.getTag();
        }
        viewHolder.siv.setImageUrl(newsinfo.getIcon());
        viewHolder.tv_title.setText(newsinfo.getTitle());//传递题目
        viewHolder.tv_description.setText(newsinfo.getDescription());
        viewHolder.tv_type.setText(newsinfo.getType()+"");
        return view;
    }
    class viewHolder{//添加类，封装需要查找的控件
        TextView tv_title;
        TextView tv_description;
        TextView  tv_type;
        SmartImageView siv;

    }
}

5、创建工具类解析xml文件JsonParse.Java

package cn.edu.bzu.anew.Tools;

import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;

import java.lang.reflect.Type;
import java.util.List;

import cn.edu.bzu.anew.entity.NewsInfo;

/**
 * Created by Administrator on 2017/5/18.
 */

public class JsonParse {
    public  static List<NewsInfo>getNewsInfo(String json){
        Gson gson =new Gson();
        Type listType=new TypeToken<List<NewsInfo>> (){
        }.getType();
        List<NewsInfo>newsInfos=gson.fromJson(json,listType);
        return  newsInfos;
    }
}

6、编写界面交互代码（MainActivity）

package cn.edu.bzu.anew;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Toast;

import com.loopj.android.http.AsyncHttpClient;
import com.loopj.android.http.AsyncHttpResponseHandler;

import java.io.UnsupportedEncodingException;
import java.util.List;

import cn.edu.bzu.anew.Tools.JsonParse;
import cn.edu.bzu.anew.adapter.NewsAdapter;
import cn.edu.bzu.anew.entity.NewsInfo;


public class MainActivity extends AppCompatActivity {
    private ListView lvNews;
    private List<NewsInfo>  newsInfos;
    private LinearLayout loading;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lvNews=(ListView)findViewById(R.id.lv_news);
        loading=(LinearLayout)findViewById(R.id.loading);
        fillData();

    }
    private  void  fillData(){
        AsyncHttpClient client =new  AsyncHttpClient();

        client.get("http://10.51.26.107:8080/NewsInfo.json",new AsyncHttpResponseHandler(){
            @Override
            public void onSuccess(int i, org.apache.http.Header[] headers, byte[] bytes) {
                try{
                    String json=new String(bytes,"utf-8");
                    newsInfos= JsonParse.getNewsInfo(json);
                    if(newsInfos==null){
                        Toast.makeText(MainActivity.this,"解析失败", Toast.LENGTH_LONG).show();
                    }else{
                        loading .setVisibility(View.INVISIBLE);
                        lvNews.setAdapter(new NewsAdapter(MainActivity.this,newsInfos));
                    }
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
            }

            @Override
            public void onFailure(int i, org.apache.http.Header[] headers, byte[] bytes, Throwable throwable) {

            }
        } );


    }
}

7、配置服务器

在Tomcat根目录下找到bin文件夹，运行该文件夹下的startup.bat文件即可开启Tomcat服务器。然后，在Tomcat的安装目录下打开webapps文件夹，将NewsInfo.Json文件及所需的图片文件放置在ROOT文件夹下。NewsInfo.Json代码如下：（将这里的IP地址及MainActivity中的IP地址换成本机的IP地址）

 {
    "icon": "http://10.51.26.107:8080/images/a.jpg",
    "title": "科技温暖世界",
    "content": "进入一个更有爱的领域",
    "type": "1",
    "comment": "69"
  },
  {
    "icon": "http://10.51.26.107:8080/images/b.jpg",
    "title": "《神武》",
    "content": "新美术资源盘点，视觉新体验",
    "type": "2",
    "comment": "35"
  },
  {
    "icon": "http://10.51.26.107:8080/images/c.jpg",
    "title": "南北车正式公布合并",
    "content": "南北车将于今日正式公布合并",
    "type": "3",
    "comment": "2"
  },
  {
    "icon": "http://10.51.26.107:8080/images/d.jpg",
    "title": "萌呆了！汪星人抱玩偶酣睡",
    "content": "汪星人抱玩偶酣睡，萌翻网友",
    "type": "1",
    "comment": "25"
  },
  {
    "icon": "http://10.51.26.107:8080/images/e.jpg",
    "title": "风力发电进校园",
    "content": "风力发电普进校园",
    "type": "2",
    "comment": "26"
  },
  {
    "icon": "http://10.51.26.107:8080/images/f.jpg",
    "title": "地球一小时",
    "content": "地球熄灯一小时",
    "type": "1",
    "comment": "23"
  },
  {
    "icon": "http://10.51.26.107:8080/images/g.jpg",
    "title": "最美公路",
    "content": "最美公路，难以想象",
    "type": "1",
    "comment": "23"
  }