我想从 SQLite 数据库中的 2 个表中填充一个列表视图。列表视图将包含 3 个视图:一个图像视图和 2 个文本视图。
- 第一个表:imageview 和 textview1
- 第二个表:textview2
我可以成功地从一个表中查询数据并将其显示在列表视图中,但不知道如何从第二个表中查询,然后将其添加到列表中。
下面的代码显示一个列表视图,其中仅包含来自 my_folders 的数据。如何更改它,以便 textview1 显示来自表 my_folders 的数据,而 textview2 显示来自 my_expenses 的数据。有人可以帮忙吗?
这是我的主要内容:
公共类 mymain 扩展 ListActivity { ListView listContent;
SimpleCursorAdapter 光标适配器;final DBAdapter mySQLiteAdapter = new DBAdapter(this); 光标光标;
/** 在第一次创建活动时调用。*/
@Override public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// setContentView(R.layout.list_example);
listContent = (ListView) findViewById(R.id.custom_list); final DBAdapter mySQLiteAdapter = new DBAdapter(this); mySQLiteAdapter.open(); cursor = mySQLiteAdapter.getAllFolders(); String[] from = new String[] { DBAdapter.KEY_NAME,DBAdapter.KEY_CURRENCY }; int[] to = new int[] { R.id.name_row, R.id.notes_row }; cursorAdapter = new SimpleCursorAdapter(this, R.layout.list_row, cursor, from, to); setListAdapter(cursorAdapter); mySQLiteAdapter.close();
} }
这是我的数据库:
import android.database.Cursor;
public class DBAdapter {
public static final String KEY_ROWID = "_id";
public static final String KEY_NAME = "name";
public static final String KEY_CURRENCY = "currency";
public static final String KEY_NOTES = "notes";
public static final String KEY_EXPENSE_NAME = "expense_name";
public static final String KEY_EXPENSE_AMOUNT = "expense_amount";
public static final String KEY_EXPENSE_DATE = "expense_date";
public static final String KEY_EXPENSE_TIME = "expense_time";
public static final String KEY_EXPENSE_NOTES = "expense_notes";
public static final String KEY_EFOLDERID = "e_fid";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "MyDB";
private static final String DATABASE_TABLE1 = "my_folders";
private static final String DATABASE_TABLE2 = "my_expenses";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE_FOLDERS =
"create table my_folders (_id integer primary key autoincrement, "
+ "name text not null, currency text not null, notes text);";
private static final String DATABASE_CREATE_EXPENSES =
"create table my_expenses (_id integer primary key autoincrement, "
+ "expense_name text not null, expense_amount real not null, " +
"expense_date text not null, expense_time text not null," +
"expense_notes text,"
+ "e_fid integer not null," +
"FOREIGN KEY ("+ KEY_EFOLDERID+ ") REFERENCES " + DATABASE_TABLE1 +" ("+ >KEY_ROWID + ") ON DELETE CASCADE);";
// ---retrieves all the contacts---
public Cursor getAllFolders() {
return db.query(DATABASE_TABLE1, new String[] { KEY_ROWID, KEY_NAME,
KEY_CURRENCY, KEY_NOTES}, null, null, null, null, null);
}
// ---retrieves all the expenses---
public Cursor getAllExpenses() {
return db.query(DATABASE_TABLE2, new String[] { KEY_ROWID, KEY_EXPENSE_NAME,
KEY_EXPENSE_AMOUNT, KEY_EXPENSE_DATE, KEY_EXPENSE_TIME, KEY_EXPENSE_NOTES, >KEY_EFOLDERID}, null, null, null, null, null);
}