ListView(列表视图)应用实例

1.文字列表

MainAtivity.java：

public class MainActivity extends Activity {
@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//获取ListView对象
		ListView listview = findViewById(R.id.listview);
		//准备数据源
		String[] data = {
		"初识安卓",
		"开发环境搭建",
		"基础控件",
		"线性布局",
		"相对布局"};
		//配置数组适配器
		ArryAdapter<String> dadpter
		= new ArrayAdapter<String>(
		this,
		android.R.layout.Simple_list_item_1,//系统自带布局
		data);
		//绑定适配器
		listview.setAdapter(adapter);

activity_main.xml：

//添加ListView
<LinearLayout  
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
	<ListView
		android:id="id/listview"
		android:layout_width="match_parent"
		android:layout_height="match_parent"/>
</LinearLayout>

展示图：

2.图文列表

MainActivity.java：

public class MainActivity extends AppCompatActivity {
    private ListView lv_main;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.simpleList);
        //获取ListView对象
        ListView lv = findViewById(R.id.iv_main);
        //准备数据源
        List<Map<String, Object>> List = new 	ArrayList<Map<String, Object>>();
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("logo", R.drawable.keeplogo);
        map.put("title", "KEEP");
        map.put("version", "版本：5.2.0");
        map.put("size", "大小：281M");
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo1);
        map.put("title", "智能管家");
        map.put("version", "版本：8.4.0");
        map.put("size", "大小：32.81M");
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo2);
        map.put("title", "LOG健身");
        map.put("version", "版本：5.4.0");
        map.put("size", "大小：132.81M");
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo3);
        map.put("title", "余额宝");
        map.put("version", "版本：2.7.0");
        map.put("size", "大小：67.40M");
        List.add(map);
		
       //配置简单适配器
       SimpleAdapter adapter = new SimpleAdapter(
       		this,//上下文
       		List,//数据源
       		R.layout.item,//行布局
       		//Map中的key
       		new string[]{"logo","title","version","size"},
       		//控件id
       		new int[]
       		{R.id.logo,R.id.title,R.id.version,R.id.size}
       );
       //绑定适配器
       lv.setAdapter(adapter);
}

item.xml(自定义行布局文件)：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    //item获取焦点
    android:descendantFocusability="blocksDescendants"
    >
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="5dp"
        android:layout_marginRight="5dp"
        android:paddingLeft="5dp"
        android:paddingTop="5dp"
        android:paddingBottom="5dp"
        android:paddingRight="3dp"
        >
        <ImageView
            android:layout_width="70dp"
            android:layout_height="70dp"
            android:id="@+id/logo"
            />
        <RelativeLayout
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_toLeftOf="@+id/button"
            android:layout_toRightOf="@+id/logo"
            android:layout_marginLeft="5dp"
            >
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/title"
                android:textColor="#444444"
                android:textSize="16sp"
                />
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/vertion"
                android:textColor="#999"
                android:layout_marginTop="6dp"
                android:textSize="12sp"
                android:layout_below="@+id/title"
                />
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/size"
                android:textColor="#999"
                android:textSize="12sp"
                android:layout_marginTop="6dp"
                android:layout_below="@+id/vertion"
                />
	</RelativeLayout>
        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:text="下载" />
</RelativeLayout>

simpleList.xml：

<RelativeLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" 
    android:layout_height="match_parent"
    >
    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/iv_main"
        //item选中背景改变
        android:listSelector="@drawable/item">

    </ListView>
</RelativeLayout>

展示图：

自定义列表(采用ViewHolder和convertView优化)

MainAcivity.java：

public class MainActivity extends AppCompatActivity {
    private ListView lv_main;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.myList);
        //获取listview对象
        ListView lv = findViewById(R.id.iv_main);
        //向map对象中存入键值对数据
        List<Map<String, Object>> List = new ArrayList<Map<String, Object>>();   
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("logo", R.drawable.keeplogo);
        map.put("title", "KEEP");
        map.put("version", "版本：5.2.0");
        map.put("size", "大小：281M");
        //将map对象存入List容器中
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo1);
        map.put("title", "智能管家");
        map.put("version", "版本：8.4.0");
        map.put("size", "大小：32.81M");
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo2);
        map.put("title", "LOG健身");
        map.put("version", "版本：5.4.0");
        map.put("size", "大小：132.81M");
        List.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.logo3);
        map.put("title", "余额宝");
        map.put("version", "版本：2.7.0");
        map.put("size", "大小：67.40M");
        List.add(map);
		//绑定适配器
        MyAdapter adapter = new MyAdapter(List，this);
		
        lv.setAdapter(adapter);
    }

/配置适配器/

Myadapter.java：

public class MyAdapter extends BaseAdapter {
	//定义对象
	private Context context;
    private List<Map<String, Object>> List;/
    private LayoutInflater inflater;
    
    //初始化对象
	public MyAdapter(List<Map<String, Object>> List, Context context) {
		this.context = context;
        this.List = List;
        inflater = LayoutInflater.from(context);
    }

	//获取列表总长度
    @Override
    public int getCount() {
        return List.size();
    }
	//获取当前item的position
    @Override
    public Object getItem(int i) {
        return List.get(i);
    }
	//获取当前item的id
    @Override
    public long getItemId(int i) {
        return i;
    }
	//获取View对象
    @Override
    public View getView(final int i, View convertView, ViewGroup viewGroup){
    	//定义ViewHolder
        ViewHolder holder = null;
       //添加viewHolder类
    	public class ViewHolder {
        ImageView logo;
        TextView title;
        TextView version;
        TextView size;
    }
        if (convertView == null) {
			//将行布局文件转化为convertView对象
            convertView = inflater.inflate(R.layout.item, null);
           //实例化viewholder
            holder = new ViewHolder();
         	//获取控件对象
            holder.logo = convertView.findViewById(R.id.logo);
            holder.title =  convertView.findViewById(R.id.title);
            holder.version = convertView.findViewById(R.id.vertion);
            holder.size = convertView.findViewById(R.id.size);
            //保存viewholder
            convertView.setTag(holder);
        } else {
        	//取出viewholder
            holder = (ViewHolder) convertView.getTag();
        }
		//将数据传递给控件
        Map map = List.get(i);
        holder.logo.setImageResource((Integer) map.get("logo"));
        holder.title.setText((String) map.get("title"));
        holder.version.setText((String) map.get("version"));
        holder.size.setText((String) map.get("size"));
   		//返回convertView
        return convertView;
    }
}

item.xml(自定义行布局文件)：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    //item获取焦点
    android:descendantFocusability="blocksDescendants"
    >
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="5dp"
        android:layout_marginRight="5dp"
        android:paddingLeft="5dp"
        android:paddingTop="5dp"
        android:paddingBottom="5dp"
        android:paddingRight="3dp"
        >
        <ImageView
            android:layout_width="70dp"
            android:layout_height="70dp"
            android:id="@+id/logo"
            />
        <RelativeLayout
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_toLeftOf="@+id/button"
            android:layout_toRightOf="@+id/logo"
            android:layout_marginLeft="5dp"
            >
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/title"
                android:textColor="#444444"
                android:textSize="16sp"
                />
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/vertion"
                android:textColor="#999"
                android:layout_marginTop="6dp"
                android:textSize="12sp"
                android:layout_below="@+id/title"
                />
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/size"
                android:textColor="#999"
                android:textSize="12sp"
                android:layout_marginTop="6dp"
                android:layout_below="@+id/vertion"
                />
	</RelativeLayout>
        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:text="下载" />
</RelativeLayout>

myList.xml：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >
    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/iv_main"
        android:listSelector="@drawable/item">
    </ListView>
</RelativeLayout>

展示图：