将数据库内容显示到listView-游标适配器

游标适配器的使用

/*
将sd卡上的数据库内容显示到listView上,需要读取sd卡权限
 */
public class CursorAdapterActivity extends Activity {

    private ListView lvPersons;
    private Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.context = CursorAdapterActivity.this;
        String path = Environment.getExternalStorageDirectory().getAbsolutePath() +"/person_db.db";
        //直接打到指定路径的数据库
        SQLiteDatabase db = SQLiteDatabase.openDatabase(path, null, SQLiteDatabase.OPEN_READWRITE);
        Cursor cursor = db.rawQuery("select * from person",null);//查询到所有数据
        
        
        lvPersons = (ListView) findViewById(R.id.lv_persons);
        //实现自定义cursoradapter
        MyCrusorAdapter myCrusorAdapter = new MyCrusorAdapter(context, cursor);
        lvPersons.setAdapter(myCrusorAdapter);
    }
   //直接使用游标适配器
    class MyCrusorAdapter extends CursorAdapter{

        public MyCrusorAdapter(Context context, Cursor c) {
            super(context, c, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
        }

        /* 返回一个item的view (不绑定数据)
         * 
         */
        @Override
        public View newView(Context context, Cursor cursor, ViewGroup parent) {
            View view = View.inflate(context, R.layout.listview_item_person, null);
            return view;
        }

        /* 将数据绑定到item的view中
         * 
         */
        @Override
        public void bindView(View view, Context context, Cursor cursor) {
              //找到listView的item控件
              TextView tvName = (TextView) view.findViewById(R.id.tv_name);
              TextView tvAge= (TextView) view.findViewById(R.id.tv_age);
            
              //填充数据
              tvName.setText(cursor.getString(cursor.getColumnIndex("name")) + "hhh");
              tvAge.setText(cursor.getInt(cursor.getColumnIndex("age")) + "");
        }    
    }
}

SimpleCursorAdapter的使用:

        //打开已经存在的数据库
        //获得路径
         String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/person_db.db";
        
        
//        String path,  数据库的文件路径
//        CursorFactory factory, 游标工厂, null表示默认的
//        int flags  权限        SQLiteDatabase.OPEN_READWRITE表示可读可写
        SQLiteDatabase db = SQLiteDatabase.openDatabase(path, null, SQLiteDatabase.OPEN_READWRITE);
        //查询数据
        Cursor cursor = db.query("person", null, null, null, null, null, null, null);
        
        lvPersons = (ListView) findViewById(R.id.lv_persons);
        //设置SimpleCursorAdapter  
//        Context,
//        int,  item布局的id
//        Cursor, 数据源
//        String[],  列名的string数组
//        int[]     布局文件中控件的id与上个参数的列名对应
        SimpleCursorAdapter simpleCursorAdapter = new SimpleCursorAdapter(MainActivity.this, R.layout.listview_item_person,cursor, new String[]{"name","age"}, new int[]{R.id.tv_name,R.id.tv_age});
        lvPersons.setAdapter(simpleCursorAdapter);