[問題] SimpleCursorAdapter 無法執行

看板AndroidDev作者jain00 (魔流)時間13年前 (2011/08/27 10:01)推噓0(0推 0噓 1→)

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目前在寫SQLite的程式，但在做SimpleCursorAdapter時，無法將資料顯示，照書上範本修改還是不行，不知是否那裡有問題，以下是程式碼: 取得資料: public class mySQLiteOpenHelper extends SQLiteOpenHelper { private final static String DATABASE_NAME = "todo_db.db"; private final static int DATABASE_VERSION = 1; private final static String TABLE_NAME = "todo_table"; public final static String FIELD_id = "id"; public final static String FIELD_TEXT = "context"; private SQLiteDatabase db; public mySQLiteOpenHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); db = this.getWritableDatabase(); } @Override public void onCreate(SQLiteDatabase db) { String sql = "CREATE TABLE " + TABLE_NAME + " (" + FIELD_id + " INTEGER primary key autoincrement, " + " " + FIELD_TEXT + " text)"; db.execSQL(sql); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { String sql = "DROP TABLE IF EXISTS " + TABLE_NAME; db.execSQL(sql); onCreate(db); } public Cursor select() { SQLiteDatabase db = this.getReadableDatabase(); Cursor cursor = db.query(TABLE_NAME, null, null, null, null, null, null); return cursor; } public long insert(String text) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues args = new ContentValues(); args.put(FIELD_id, 2); args.put(FIELD_TEXT, text); return db.insert(TABLE_NAME, null, args); } public void delete(int id) { SQLiteDatabase db = this.getWritableDatabase(); String where = FIELD_id + " = ?"; String[] whereValue = { Integer.toString(id) }; ContentValues c= new ContentValues(); db.delete(TABLE_NAME, "id=?", new String[]{"2"}); } public void update(int id, String text) { /* SQLiteDatabase db = this.getWritableDatabase(); String where = FIELD_id + " = ?"; String[] whereValue = { Integer.toString(id) }; */ SQLiteDatabase db = this.getWritableDatabase(); db.execSQL("update todo_table set context='C' where id=2"); } } 主程式: public class GDD02 extends Activity { private mySQLiteOpenHelper gaaSQLiteOpenHelper; private Cursor myCursor; private ListView myListView; private EditText myEditText; private int _id; protected final static int MENU_ADD = Menu.FIRST; protected final static int MENU_EDIT = Menu.FIRST + 1; protected final static int MENU_DELETE = Menu.FIRST + 2; @Override public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); switch (item.getItemId()) { case MENU_ADD: this.addTodo(); break; case MENU_EDIT: this.editTodo(); break; case MENU_DELETE: this.deleteTodo(); break; } return true; } @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); menu.add(0, MENU_ADD, 0, "MENU_ADD"); menu.add(0, MENU_EDIT, 0, "MENU_EDIT"); menu.add(0, MENU_DELETE, 0, "MENU_DELETE"); return true; } /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); myListView = (ListView) this.findViewById(R.id.myListView); myEditText = (EditText) this.findViewById(R.id.myEditText); gaaSQLiteOpenHelper = new mySQLiteOpenHelper(this); myCursor = gaaSQLiteOpenHelper.select(); startManagingCursor(myCursor); //這是資料庫欄位 String[] columns = new String[]{gaaSQLiteOpenHelper.FIELD_TEXT}; //要顯示的元件 int[] to = new int[]{R.id.listView1}; SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.list ,myCursor, columns, to ); gaaSmyListView.setAdapter(adapter); } } -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.227.145.245