从数据库中获得的数据的Andr​​oid [英] Get data from database Android

问题描述

我有一个网页，它可以从数据库中检索用户数据
但试图整天之后，我只能够得到表的列名而不是里面的值。

I have a page which can retrieve user data from database but after whole day of trying, I am only able to get the table column name but not the value inside.

这是我的code创建数据库

 public static final String LASTLOGIN = "lastuser"; 
 public static final String USER_ID = "suser_id";
 public static final String USER_NAME = "suser_name";
 public static final String USER_PASSWORD = "spassword";
 public static final String PRIME_ID = "id";

 private static final String TABLE_USER = 
         "create table "+ LASTLOGIN+" ("
        +PRIME_ID+" integer primary key autoincrement, "
        + USER_ID + " text, "
        + USER_NAME +" text, "
        +USER_PASSWORD+" text); ";

，这里是实现获取用户数据的功能

public Cursor getuser()
{
    String[] columns = new String[]{PRIME_ID, USER_NAME, USER_PASSWORD};
    Cursor cursor = sqLiteDatabase.query(
           LASTLOGIN, columns, null, null, null, null, PRIME_ID +" DESC");
    Log.d("TAG", columns[1]);
    return cursor;
}

这里是我的code来显示结果

mySQLiteAdapter = new SQLiteAdapter(this);
mySQLiteAdapter.openToWrite();

cursor = mySQLiteAdapter.getuser();
String[] resultvalue = new String{
         SQLiteAdapter.PRIME_ID,SQLiteAdapter.USER_NAME, SQLiteAdapter.USER_PASSWORD};
Toast.makeText(this, resultvalue[0]+resultvalue[1], Toast.LENGTH_LONG).show();

和敬酒结果只显示列名而不是里面的价值，没有任何错误，我做？我想限制设置为1，但在那里设置呢？

and the toast result only show the column name but not the value inside, is there any mistake i made? and I want to set limit to 1, but where to set it?

感谢您帮助我

推荐答案

您尝试阅读的价值观是完全地错误的方式。
创建数组

the way you try reading the values is completly wrong. you create an array

String[] resultvalue = new String[]{
                       SQLiteAdapter.PRIME_ID,
                       SQLiteAdapter.USER_NAME,
                       SQLiteAdapter.USER_PASSWORD};

后您从该阵列读出的值0和1。
你的面包是绝对工作正常becouse这个数组中定义的列名！

after that you read the values 0 and 1 from this array. Your toast works absolutly correctly becouse inside this array you define the column names!

如果你想显示从您的查询值做这种方式：

If you want to show the values from your query do it this way:

    while(cursor.moveToNext()){
            Integer str1 = str 1 + cursor.getInteger(1);
            String str2 =str2 + cursor.getString(2);
       Toast.makeText(this, str1 + str2, Toast.LENGTH_LONG).show();
    }

或更好的方式接收正确的索引：

or a better way receiving the correct index:

cursor.getInteger( cursor.getColumnIndex(SQLiteAdapter.PRIME_ID) );
cursor.getString( cursor.getColumnIndex(SQLiteAdapter.USER_NAME) );

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