從多個表中檢索數據 - Android Eclipse

我正在使用UNION從多個表執行搜索界面。搜索詞被過濾的類是SimpleCursorAdapter表單，我的問題是當我單擊搜索到的單詞時，我看到的唯一一個白色空白頁。從多個表中檢索數據 - Android Eclipse

這是我的代碼來檢索'更多信息'的話。我認爲問題出在WHERE條件。請幫幫我。謝謝。

commandId = getIntent().getIntExtra("COMMAND_ID", 0); 
SQLiteDatabase db = (new DBHelper(this)).getWritableDatabase(); 
final String commandIdString = String.valueOf(commandId); 
Cursor cursor = db.rawQuery("SELECT _id AS _id, name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_acc WHERE _id = ? " + 
     "UNION SELECT _id AS _id, name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_filems WHERE _id = ? " + 
     "UNION SELECT _id AS _id, name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_psu WHERE _id = ? " + 
     "UNION SELECT _id AS _id, name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_shells WHERE _id = ? " + 
     "UNION SELECT _id AS _id, name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_sic WHERE _id = ? " + 
     "UNION SELECT _id AS _id,name AS name, desc AS desc, syntax AS syntax, option AS option FROM comm_stp WHERE _id = ?", 
     new String[]{commandIdString, commandIdString, commandIdString, commandIdString, commandIdString, commandIdString}); 


if (cursor.getCount() == 1) 
{ 
     cursor.moveToFirst(); 

     commandName = (TextView) findViewById (R.id.commandName); 
     commandName.setText(cursor.getString(cursor.getColumnIndex("name"))); 

     commandDesc = (TextView) findViewById (R.id.commandDesc); 
     commandDesc.setText(cursor.getString(cursor.getColumnIndex("desc"))); 

     commandSyntax = (TextView) findViewById (R.id.commandSyntax); 
     commandSyntax.setText(cursor.getString(cursor.getColumnIndex("syntax"))); 

     commandOption = (TextView) findViewById (R.id.commandOption); 
     commandOption.setText(cursor.getString(cursor.getColumnIndex("option"))); 

} 

}

來源

2014-12-04 user3398666

您是否對數據庫使用了生成的SQL查詢？ – Smutje 2014-12-04 14:54:04

它不會解決你的問題，但：「」+ commandId是凌亂的。爲什麼不使用：String.valueOf（commandId），而不是？ – LokiSinclair 2014-12-04 14:54:13

我已經編輯了代碼，請再看一遍。它仍然是白色的空白頁面。 – user3398666 2014-12-04 16:16:30

爲了在你的原始查詢中使用的每個參數，你必須設置的值來代替，所以

new String[]{""+commandId}

只適合在列表中的第一個參數。將其替換爲

final String commandIdString = String.valueOf(commandId); 
new String[]{commandIdString, commandIdString, commandIdString, commandIdString, commandIdString, commandIdString}

來源

2014-12-04 14:56:29 Smutje

仍然一樣，只有白頁。請再看一遍，我編輯了代碼。 – user3398666 2014-12-04 15:54:55

關於「你使用了對數據庫產生的SQL查詢嗎？」 - 排除SQL語法相關問題的一部分？ – Smutje 2014-12-04 19:06:52

是的，我試過沒有WHERE條件執行它，它工作正常。我的WHERE條件有什麼問題嗎？ – user3398666 2014-12-05 01:10:49

從多個表中檢索數據 - Android Eclipse

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