新闻客户端

1.创建程序:
创建一个名为”ImageBrowser”的应用程序，设计用户交互界面：
布局文件(activity_main.xml):

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".MainActivity"    android:orientation="vertical">    <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"            android:layout_marginTop="5dp"/>    </FrameLayout></LinearLayout>

2.创建ListView Item的布局
因为使用了ListView控件，需要为ListView的item创建一个布局。ListView Item布局文件news_item.xml：

<?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:layout_alignParentLeft="true"        android:layout_alignParentStart="true"        android:scaleType="centerCrop"        android:src="@mipmap/ic_launcher"></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.编写界面交互代码（MainActivity）：

<?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:layout_alignParentLeft="true"        android:layout_alignParentStart="true"        android:scaleType="centerCrop"        android:src="@mipmap/ic_launcher"></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>

4.创建适配器MyAdapter类：

package bzu.edu.cn.imagebrowser.adapter;import android.content.Context;import android.graphics.Color;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 org.w3c.dom.Text;import java.util.List;import bzu.edu.cn.imagebrowser.R;import bzu.edu.cn.imagebrowser.entity.NewsInfo;public class MyAdapter extends ArrayAdapter<NewsInfo>{    public MyAdapter(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);        View view;        ViewHolder viewHolder;        if(convertView==null){            view= LayoutInflater.from(getContext()).inflate(R.layout.news_item, null);            viewHolder=new ViewHolder();            viewHolder.siv_icon=(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);        }        else{            view=convertView;            viewHolder=(ViewHolder)view.getTag();        }        viewHolder.siv_icon.setImageUrl(newsInfo.getIcon());        viewHolder.tv_title.setText(newsInfo.getTitle());        viewHolder.tv_description.setText(newsInfo.getContent());        int type=newsInfo.getType();        switch (type){            case 1:                viewHolder.tv_type.setText("评论:"+newsInfo.getComment());                break;            case 2:                viewHolder.tv_type.setTextColor(Color.RED);                viewHolder.tv_type.setText("专题");                break;            case 3:                viewHolder.tv_type.setTextColor(Color.BLUE);                viewHolder.tv_type.setText("LIVE");                break;        }        return view;    }    class ViewHolder{        SmartImageView siv_icon;        TextView tv_title;        TextView tv_description;        TextView tv_type;    }}

创建JsonParse；

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;    }}

5:创建NewsInfo类：

public class NewsInfo {    private String icon;//图片路径    private String title;//新闻标题    private String content;//新闻内容    private int type;//新闻类型    private long comment;//新闻评论数    public long getComment() {        return comment;    }    public void setComment(long comment) {        this.comment = comment;    }    public int getType() {        return type;    }    public void setType(int type) {        this.type = type;    }    public String getContent() {        return content;    }    public void setContent(String description) {        this.content = content;    }    public String getTitle() {        return title;    }    public void setTitle(String title) {        this.title = title;    }    public String getIcon() {        return icon;    }    public void setIcon(String icon) {        this.icon = icon;    }}

6配置服务器
由于需要从服务器上下载一个XML，因此需要开启tomcat 服务器，在tomcat根目录下找pin文件夹，运行该文件夹下的startup.bat文件即可开启tomcat 服务器，然后再tomcat的安装目录打开webapps文件夹，将NewsInfo.xml文件放置在ROOT文件夹下，NewsInfo.xml代码:

{    "icon": "http://192.168.1.109:8080/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://192.168.1.109:8080/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://192.168.1.109:8080/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://192.168.1.109:8080/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://192.168.1.109:8080/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://192.168.1.109:8080/images/f.jpg",    "title": "地球一小时",    "content": "地球熄灯一小时",    "type": "1",    "comment": "23"  },  {    "icon": "http://192.168.1.109:8080/images/g.jpg",    "title": "最美公路",    "content": "最美公路，难以想象",    "type": "1",    "comment": "23"  }]

7.清单文件添加权限(AndroidMainfest.xml）：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="bzu.edu.cn.imagebrowser">    <uses-permission android:name="android.permission.INTERNET" />    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="ImageBrowser"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <activity android:name=".MainActivity">        </activity>        <activity android:name=".Main2Activity" android:label="News">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>