Question

我正在使用UNION从多个表执行搜索界面。搜索单词被过滤的类是SimpleCursorAdapter形式，我的问题是当我点击搜索到的单词以获取其信息时，我看到的唯一的东西是白色空白页。

这是我的代码，用于检索“获取更多信息”字样。我认为问题出在WHERE条件下。请帮我。感谢。

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")));

}

}

Answer 1

对于您在原始查询中使用的每个参数，您必须将值设置为replace，所以

new String[]{""+commandId}

仅适用于列表中的第一个参数。替换为

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

从多个表中检索数据 - Android Eclipse

1 个答案: