SQL查詢不通過我正在寫一個Android應用程序的參數

Question

，我需要搜索數據的基礎上，這是我使用的方法：

public Cursor getData(String table, String keyword, SQLiteDatabase db){ 

    String selection; 
    Cursor cursor; 

    switch (table){ 
     case "User": 
      String [] projection = {id,name,phone}; 
      selection = "username LIKE ?"; 
      String [] selection_arg = {keyword}; 
      cursor = db.query("User",projection,selection,selection_arg,null,null,null); 
      break; 
     //omitted 
     default: 
      return null; 
    } 
    return cursor; 

用戶投放關鍵字

keyword = search_user.getText().toString(); 
Cursor cursor = dbHelper.getData(ShippingApplication.User.USER_TABLE,keyword,db); 

代碼不工作，當我調試，我看到DB變量的mQuery是： SQLiteQuery: SELECT userID, userName, phoneNumber FROM User WHERE userName LIKE ? 它看起來像查詢不傳遞到SQL命令的關鍵字的值。 有人能告訴我什麼是錯的？

編輯2：我更改代碼一點點，現在它的工作原理：

String selection = ShippingApplication.User.name + " LIKE '%" + keyword + "%'"; 
Cursor cursor = db.query(The table name,projection,selection,null,null,null,null); 

Answer 1

嘗試這種方式

請檢查您的SQLiteDatabase對象不是空

之後檢查表是否被創建

我得到的遊標數我已經調試它，它的工作對我罰款

public Cursor getData(String table, String keyword, SQLiteDatabase db){ 

     String selection; 
     Cursor cursor; 

     switch (table){ 
      case "Tbl_staticContent": 
       String [] projection = {"PageTitle","Content"}; 
       selection = "PageTitle LIKE ?"; 
       String [] selection_arg = {keyword}; 
       cursor = db.query("Tbl_staticContent",projection,selection,selection_arg,null,null,null); 

       Log.e("count",""+cursor.getCount()); 
       //I have create table and stored data and also check the like condtion also it's work fine and get the cursor.getCount() > 0 also . 

       break; 

      default: 
       return null; 
     } 
     return cursor; 
}