ArrayAdapter_SimpleAdapter_SimpleCursorAdapter+SQL
ArrayAdapter_SimpleAdapter:
1 private ListView listview; 2 private ArrayAdapter<String>arr_adapter; 3 private SimpleAdapter simp_adapter; 4 private List<Map<String,Object>>dataList; 5 6 @Override 7 protected void onCreate(Bundle savedInstanceState) { 8 super.onCreate(savedInstanceState); 9 setContentView(R.layout.activity_man); 10 listview = (ListView)findViewById(R.id.listView1); 11 12 String[]arr_data={"传说中的数据源1","传说中的数据源2","传说中的数据源3","传说中的数据源4"}; 13 14 //新建一个适配器 15 //参数:1.上下文 2.当前Listview加载的每一个列表项所对应的布局文件3.数据源 16 //arr_adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arr_data); //普通文字适配器 17 //视图加载适配器 18 //listview.setAdapter(arr_adapter); 19 20 dataList = new ArrayList<Map<String,Object>>(); 21 simp_adapter = new SimpleAdapter(this, getData(), R.layout.item, new String[]{"img","text"}, new int[]{R.id.img,R.id.text}); 22 /*1.上下文 23 * 2.data: 数据源 List<? extends Map<String, ?>> data (一个map所组成的list集合) 24 * 每一个Map都会去对应ListView中的一行 25 * 每一个Map(键——值对)中的键必须包含所有在from中所指定的键 26 * 3.resource:列表项的布局文件ID 27 * 4.from:Map中的键名 28 * 5.to:绑定数据视图中的ID。与from成对应关系 29 */ 30 listview.setAdapter(simp_adapter); 31 } 32 33 private List<Map<String,Object>> getData(){ 34 35 for(int i = 0; i < 20; i++){ 36 Map<String, Object>map = new HashMap<String, Object>(); 37 map.put("img", R.drawable.ic_launcher); 38 map.put("text", "传说中的数据源"+i); 39 dataList.add(map); 40 } 41 42 return dataList; 43 }
SimpleCursorAdapter:
1 public class ManActivity extends Activity { 2 private EditText ed1 = null; 3 private EditText ed2 = null; 4 private Button btn = null; 5 private ListView listview = null; 6 private SimpleCursorAdapter adapter; 7 private MySql mysql = null; 8 9 @Override 10 protected void onCreate(Bundle savedInstanceState) { 11 super.onCreate(savedInstanceState); 12 setContentView(R.layout.activity_man); 13 this.mysql = new MySql(ManActivity.this); 14 ed1 = (EditText)findViewById(R.id.editText1); 15 ed2 = (EditText)findViewById(R.id.editText2); 16 listview = (ListView)findViewById(R.id.listView1); 17 btn = (Button)findViewById(R.id.button1); 18 btn.setOnClickListener(new OnClickListener() { 19 public void onClick(View view) { 20 //插入数据库 21 ContentValues values = new ContentValues(); 22 values.put("name", ed1.getText().toString()); 23 values.put("sex",ed2.getText().toString()); 24 mysql.insert(values); 25 //刷新适配器 26 Cursor cursor = mysql.query(); 27 adapter.changeCursor(cursor); 28 29 } 30 }); 31 Cursor c = mysql.query(); 32 adapter = new SimpleCursorAdapter(this, R.layout.item, c, new String[]{mysql.NAME,mysql.SEX}, new int[]{R.id.textView1,R.id.textView2}); 33 listview.setAdapter(adapter); 34 //listview绑定适配器 35 36 } 37 38 @Override 39 public boolean onCreateOptionsMenu(Menu menu) { 40 // Inflate the menu; this adds items to the action bar if it is present. 41 getMenuInflater().inflate(R.menu.man, menu); 42 return true; 43 } 44 45 }
与SimpleCursorAdapter配套的SQL:
1 public class MySql extends SQLiteOpenHelper{ 2 private final static String TABLE_NAME = "user"; 3 public static final String _ID = "_id"; 4 public static final String NAME = "name"; 5 public static final String SEX = "sex"; 6 7 private SQLiteDatabase db = null; 8 9 public MySql(Context context) { 10 super(context, "user", null, 1); 11 // TODO Auto-generated constructor stub 12 } 13 14 @Override 15 public void onCreate(SQLiteDatabase db) { 16 // TODO 创建数据库 17 db.execSQL("create table if not exists "+ TABLE_NAME +" " + 18 " ("+ _ID +" integer primary key autoincrement," 19 + NAME +" text not null,"+ SEX +" text not null)"); 20 21 } 22 23 @Override 24 public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) { 25 // TODO Auto-generated method stub 26 27 } 28 29 /*插入方法*/ 30 public void insert(ContentValues values){ 31 SQLiteDatabase db = getWritableDatabase(); //获取SQLiteDatabase 32 db.insert(TABLE_NAME, null, values); //插入数据库中 33 db.close(); 34 35 } 36 /*查询方法*/ 37 public Cursor query(){ 38 SQLiteDatabase db = getReadableDatabase(); 39 Cursor cursor = db.query(TABLE_NAME, null, null, null, null, null, null); // 获取Cursor 40 return cursor; 41 } 42 /*关闭数据库*/ 43 public void close(){ 44 if(db != null){ 45 db.close(); 46 } 47 } 48 49 }
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