返回从一个SQLite数据库的所有数据到Android的两列 [英] Return all data from a SQLite DB into two columns in Android

问题描述

我想从我的两列的数据库返回的所有数据到两个不同的 TextViews 。在一个尝试，我可以返回所有的数据，但它只能在一个的TextView ，在第二次尝试，我可以让它进入两个 TextViews ，但它只返回从数据库中的第一行。首先尝试：

I'm trying to return all data from my two column DB into two different TextViews. In one attempt, I can return all the data, but it's only in one TextView, in the second attempt, I can get it into the two TextViews, but it only returns the first row from the DB. First try:

    //--- Returns only first result

//--- DB Method
public String[] getPres2() {
    String[] columns = new String[] { KEY_PRES, KEY_YEAR};
    Cursor cursor = db.query(DB_TABLE, columns, null, null, null, null, null);
    if (cursor != null) {
        cursor.moveToFirst();
        String pstYr[] = new String[2];
        pstYr[0] = cursor.getString(0);
        pstYr[1] = cursor.getString(1);
        cursor.close();
        this.db.close();
        return pstYr;
    }
    return null;

}

//--- in the activity
public void DBMethod2() {
    dba = new DBAdapter(this);
    dba.open();
    String[] pst_Str = dba.getPres2();
    dba.close();
    pst_TV.setText(pst_Str[0]);
    yrs_TV.setText(pst_Str[1]);

}

和第二次尝试：

    //--- Returns all results, but only in a single TextView
//--- DB Method
public String getPres3() {
    String[] columns = new String[] { KEY_PRES, KEY_YEAR};
    Cursor cursor = db.query(DB_TABLE, columns, null, null, null, null, null);
    String result = "";

    int iPrs = cursor.getColumnIndex(KEY_PRES);
    int iYr = cursor.getColumnIndex(KEY_YEAR);

    for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()){
        result = result + cursor.getString(iPrs) + "\n" + cursor.getString(iYr) +   "\n" + "\n";
    }

    return result;

}


//--- In Activity
public void DBMethod3() {
    dba = new DBAdapter(this);
    dba.open();
    String pstY_Str = dba.getPres3();
    dba.close();
    pst_TV.setText(pstY_Str);

}

任何帮助吗？

推荐答案

您必须在同一时间通过游标进行迭代，一排，然后使用getString语法如下：

You have to iterate through the cursor, one row at a time, and then use the GetString syntax like this:

字符串MID = cursor.getString（cursor.getColumnIndex（COLUMN_ID））;

String mId = cursor.getString(cursor.getColumnIndex(COLUMN_ID));

其中COLUMN_ID在SQLite数据库

where COLUMN_ID is the name of the column in the sqlite database

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