ListView 的标准写法

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MainActivity

public class MainActivity extends Activity {    private ListView lv;    private MyAdapter myAdapter;    private List<News> list;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        initData();        processData();    }    /**     * 找到对应的子控件     */    private void initView() {        lv = (ListView) findViewById(R.id.lv);    }    /**     * 模拟：请求服务器获取数据、解析数据的结果，即一个list集合     */    private void initData() {        list = new ArrayList<News>();        list.add(new News(R.drawable.iv1, "吉祥如意", "桃花潭水深千尺"));        list.add(new News(R.drawable.iv2, "心想事成", "明月几时有"));        list.add(new News(R.drawable.iv3, "国泰民安", "把酒问青天"));        list.add(new News(R.drawable.iv4, "虎虎生威", "故人西辞黄鹤楼"));        list.add(new News(R.drawable.iv5, "将进酒", "杯莫停，干了这杯酒"));        list.add(new News(R.drawable.iv6, "恭喜发财", "锄禾日当午"));        list.add(new News(R.drawable.iv7, "三字经", "今夕是何年"));        list.add(new News(R.drawable.iv8, "陶渊明", "采菊东篱下"));        list.add(new News(R.drawable.iv9, "田园诗人", "悠然见南山"));        list.add(new News(R.drawable.iv10, "爱莲说", "往来无白丁"));    }    /**     * 处理从服务器请求来的数据     */    private void processData() {        myAdapter = new MyAdapter(getApplication(), list);        lv.setAdapter(myAdapter);    }}

MyAdapter

public class MyAdapter extends BaseAdapter {    private Context context;    private List<News> list;    MyAdapter(Context context, List list) {        this.context = context;        this.list = list;    }    @Override    public int getCount() {        return list.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 holder;        // 把条目lv_item打气为view对象，减少findViewById的次数        if (convertView == null) {            convertView = View.inflate(context, R.layout.lv_item, null);            holder = new ViewHolder();            holder.iv = (ImageView) convertView.findViewById(R.id.iv);            holder.title = (TextView) convertView.findViewById(R.id.title);            holder.desc = (TextView) convertView.findViewById(R.id.desc);            convertView.setTag(holder);        } else {            // 复用历史缓存view对象            holder = (ViewHolder) convertView.getTag();        }        // 用list里对应对象的数据来填写对应的控件        News news = list.get(position);        holder.iv.setBackgroundResource(news.getImage());        holder.title.setText(news.getTitle());        holder.desc.setText(news.getDesc());        return convertView;    }    /**     * ViewHolder类用来管理item布局里的子控件     */    class ViewHolder {        ImageView iv;        TextView title;        TextView desc;    }}

JavaBean

public class News {    private int image;    private String title;    private String desc;    public News(int image, String title, String desc) {        super();        this.image = image;        this.title = title;        this.desc = desc;    }    public int getImage() {        return image;    }    public void setImage(int image) {        this.image = image;    }    public String getTitle() {        return title;    }    public void setTitle(String title) {        this.title = title;    }    public String getDesc() {        return desc;    }    public void setDesc(String desc) {        this.desc = desc;    }}

布局文件

<RelativeLayout 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"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.listview_demo.MainActivity" >    <ListView        android:id="@+id/lv"        android:layout_width="match_parent"        android:layout_height="match_parent" >    </ListView></RelativeLayout>

item

<?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="wrap_content"    android:layout_gravity="center_horizontal" >    <ImageView        android:id="@+id/iv"        android:layout_marginLeft="5dp"        android:layout_width="140dp"        android:layout_height="80dp"        android:background="@drawable/ic_launcher" />    <TextView        android:id="@+id/desc"        android:textColor="@android:color/black"        android:layout_marginLeft="5dp"        android:layout_width="130dp"        android:layout_height="wrap_content"        android:layout_below="@id/iv"        android:text="描述描述描述描述描述描述描述描述" />    <TextView        android:id="@+id/title"        android:textColor="@android:color/black"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_above="@+id/desc"        android:layout_alignParentRight="true"        android:layout_marginRight="5dp"        android:text="标题标题"        android:textAppearance="?android:attr/textAppearanceLarge" /></RelativeLayout>

效果

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