Android ListView 列表视图 Ⅱ 自定义适配器

新建java类 -- New -- Java Class(命名MyAdapter)

public class MyAdapter extends BaseAdapter {

    List<Map<String, Object>> list;
    LayoutInflater inflater;

    public MyAdapter(Context context) {   //Alt+Insert 自动生成代码的选项 //Alt+Insert -- Constructor -- Select None
                                          //Context类型由自己给出
        this.inflater = LayoutInflater.from(context);    //初始化反射器,from需要唯一的参数context
    }

    public void setList(List<Map<String, Object>> list) {  //Alt+Insert -- setter -- list:List<Map<String, Object>>
        this.list = list;
    }

    @Override
    public int getCount() {  //获取ListView的行数

        return list.size();
    }

    @Override
    public Object getItem(int position) {  //当前项的数据的对象

        return list.get(position);
    }

    @Override
    public long getItemId(int position) {  //当前项的id

        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
         //(资源id, view组用户类型(无实际意义))
        View view = inflater.inflate(R.layout.item, null);  //inflater:将xml文本文件反射成View对象
    }
        //拿到控件对象
        ImageView logo = (ImageView) view.findViewById(R.id.logo);
        TextView title = (TextView) view.findViewById(R.id.title);
        TextView version = (TextView) view.findViewById(R.id.version);
        TextView size = (TextView) view.findViewById(R.id.size);

        Map map = list.get(position);  //声明map临时变量,拿到键值对集合
        logo.setImageResource((Integer) map.get("logo"));  //获取资源id,key的关键字是logo
        title.setText((String) map.get("title"));
        version.setText((String) map.get("version"));
        size.setText((String) map.get("size"));

        return view;  //返回什么画什么
    }
}

Java代码 -- MainActivity

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main7);

        //1.拿到listview对象
        ListView lv = (ListView) this.findViewById(R.id.lv_main);

        //2.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.ic_10);
        map.put("title", "千千静听");
        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.ic_2);
        map.put("title", "时空猎人");
        map.put("version", "版本: 2.4.1");
        map.put("size", "大小: 84.24M");
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.ic_4);
        map.put("title", "360新闻");
        map.put("version", "版本: 6.2.0");
        map.put("size", "大小: 11.74M");
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.ic_15);
        map.put("title", "捕鱼达人2");
        map.put("version", "版本: 2.3.0");
        map.put("size", "大小: 45.53M");
        list.add(map);

        //3.实例化自己的适配器
        MyAdapter adapter = new MyAdapter(this);
        adapter.setList(list);                      //传数据


        //4.关联适配器
         lv.setAdapter(adapter);


    }

}

public class MainActivity extends Activity implements AdapterView.OnItemClickListener, AdapterView.OnItemLongClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.main7);

        //1.拿到ListView对象
        ListView lv = (ListView) this.findViewById(R.id.lv_main);

        //2.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.ic_10);
        map.put("title", "千千静听");
        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.ic_2);
        map.put("title", "时空猎人");
        map.put("version", "版本: 2.4.1");
        map.put("size", "大小: 84.24M");
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.ic_4);
        map.put("title", "360新闻");
        map.put("version", "版本: 6.2.0");
        map.put("size", "大小: 11.74M");
        list.add(map);

        map = new HashMap<String, Object>();
        map.put("logo", R.drawable.ic_15);
        map.put("title", "捕鱼达人2");
        map.put("version", "版本: 2.3.0");
        map.put("size", "大小: 45.53M");
        list.add(map);

        //3.实例化自己的适配器

        MyAdapter adapter = new MyAdapter(this);
        adapter.setList(list);

        //4.关联适配器
         lv.setAdapter(adapter);

        //5
        lv.setOnItemClickListener(this);
        lv.setOnItemLongClickListener(this);

    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        Toast.makeText(this, "点击"+position,Toast.LENGTH_SHORT).show();
    }

    @Override
    public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
        Toast.makeText(this, "长按"+position,Toast.LENGTH_SHORT).show();
        return true;
    }

}

按钮切换图片,item项切换颜色

示例1:

drawable -- btn_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

       <item android:drawable="@drawable/btn_bg2" android:state_pressed="false"/>
       <item android:drawable="@drawable/btn_bg_p" android:state_pressed="true"/>

</selector>

item.xml -- button

<Button
    android:id="@+id/btn"
    android:layout_width="66dp"
    android:layout_height="30dp"
    android:text="卸载"
    android:textSize="14sp"
    android:textColor="#fff"
    android:layout_alignParentRight="true"
    android:layout_centerVertical="true"
    android:background="@drawable/btn_selector"
    />

values -- New -- XML (新建colors.xml)

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="transparent">#00000000</color>  //透明色
    <color name="choose">#FF00EAFF</color>
</resources>

drawable -- item_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:drawable="@color/transparent" android:state_pressed="false"/>
    <item android:drawable="@drawable/fire3" android:state_pressed="true"/>


</selector>

Java代码

<?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="match_parent"
    >

    <ListView
        android:id="@+id/lv_main"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:listSelector="@drawable/item_selector"

        />

</RelativeLayout>