Android:ListView(一)

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ListView四种适配器：
1、ArrayAdapte
2、SimpleAdapter
3、SimpleCursorAdapter
4、BaseAdapter
下面是基于后面3中适配器实现的，还有一个就是SimpleAdapter的加强版，也就是plus，哈哈。主要是实现带图片功能，第一种适配器比较简单，准备用它实现显示分组。下面是实现功能截图以及代码。

这里写图片描述

上图实现的核心代码：

public class ListView1 extends Activity {    private ListView listView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.listview1);         listView = (ListView) this.findViewById(R.id.listView1);         showSimpleAdapter();    }    private void showSimpleAdapter() {        List<HashMap<String, Object>> data = new ArrayList<HashMap<String,Object>>();            for (int i = 0; i < 4; i++) {                HashMap<String, Object> item = new HashMap<String, Object>();                item.put("name","atm"+i );                item.put("age",10+i );                data.add(item);            }    /**     * Context context  上下文信息       List<? extends Map<String, ?>> data   将该数据显示在界面上       int resource     数据需要显示的地方       String[] from    从什么地方       int[] to         显示到什么地方         */        SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item,new String[]{"name", "age"}, new int[]{R.id.text1,R.id.text2});        listView.setAdapter(adapter);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        // Inflate the menu; this adds items to the action bar if it is present.        getMenuInflater().inflate(R.menu.main, menu);        return true;    }}

这里写图片描述

上图实现的核心代码：

public class ListView2 extends Activity {    private ListView listView;    private ServiceTest serviceTest;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.listview1);         listView = (ListView) this.findViewById(R.id.listView1);         serviceTest=new ServiceTest(getApplicationContext());         showSimpleCursorAdapter();    }    private void showSimpleCursorAdapter() {        Cursor cursor =serviceTest.Find_cursor();        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.item, cursor,                new String[]{"name", "age"}, new int[]{R.id.text1, R.id.text2});        listView.setAdapter(adapter);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        getMenuInflater().inflate(R.menu.main, menu);        return true;    }}

这里写图片描述

上图实现的核心代码：

public class ListView3 extends Activity {        private ListView listView;        @Override        protected void onCreate(Bundle savedInstanceState) {            super.onCreate(savedInstanceState);            setContentView(R.layout.listview2);             listView = (ListView) this.findViewById(R.id.listView2);             showSimpleAdapter();        }        private void showSimpleAdapter() {        SimpleAdapter adapter = new SimpleAdapter(                this, getData(), R.layout.item_plus,new String[]{"name", "age", "img"}, new int[]{R.id.name,R.id.age,R.id.img});            listView.setAdapter(adapter);        }        @Override        public boolean onCreateOptionsMenu(Menu menu) {            // Inflate the menu; this adds items to the action bar if it is present.            getMenuInflater().inflate(R.menu.main, menu);            return true;        }        private List<Map<String, Object>> getData() {            List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();            Map<String, Object> map = new HashMap<String, Object>();            map.put("name", "atm1");            map.put("age", 1);            map.put("img", R.drawable.img2);            list.add(map);            map = new HashMap<String, Object>();            map.put("name", "atm2");            map.put("age", 2);            map.put("img", R.drawable.love);            list.add(map);            map = new HashMap<String, Object>();            map.put("name", "atm3");            map.put("age", 3);            map.put("img", R.drawable.img1);            list.add(map);            return list;        }    }

这里写图片描述

上图实现的核心代码：

public class ListView4 extends Activity {        private ListView listView;        private ServiceTest serviceTest;        @Override        protected void onCreate(Bundle savedInstanceState) {            super.onCreate(savedInstanceState);            setContentView(R.layout.listview1);             listView = (ListView) this.findViewById(R.id.listView1);             serviceTest=new ServiceTest(this);             listView.setOnItemClickListener(new ItemClickListener());             showMyAdapter();        }        //点击后，获取给View上的数据        private final class ItemClickListener implements OnItemClickListener{            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {                ListView listview = (ListView)parent;                UserInfo userinfo = (UserInfo) listview.getItemAtPosition(position);                Toast.makeText(getApplicationContext(), userinfo.getUser_id()+"  "+userinfo.getUser_name(), 1).show();            }        }        private void showMyAdapter() {            // TODO Auto-generated method stub            List<UserInfo> list=serviceTest.Findall();            MyAdapter  myAdapter=new MyAdapter(this, list, R.layout.item);            listView.setAdapter(myAdapter);        }        @Override        public boolean onCreateOptionsMenu(Menu menu) {            // Inflate the menu; this adds items to the action bar if it is present.            getMenuInflater().inflate(R.menu.main, menu);            return true;        }    }

代码下载请点击：代码下载

补充说明：在点击SimpleAdapter前，先通过源代码中的单元测试中的方法，添加数据。

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