您好，我的数据库中有大约三个表。我希望能够在 ListView 中显示数据库中的姓名和姓氏。
- 首先我打开数据库并添加客户的名字、姓氏和电话号码。然后我关闭数据库。
- 从这里开始，我对如何在一行中显示姓名和姓氏但在 ListView 中留下数字感到困惑。
这是我的数据库类 DBAdapter 和 clientsActivity 类，我希望能够在其中显示我添加的客户端。
我知道它有点简单，但我已经完成了。毫 headless 绪，最后在学习了一些教程之后，我以 toastview 方式显示数据，这不是我想要的。
请帮忙....
我的数据库类。(DBAdapter)
package com.android.ideos;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
/**
* @author G Sam
*
*/
public class DBAdapter {
//defining columns(fields) in all 3 tables
public static final String KEY_CLIENTID = "_id";
public static final String KEY_TRANSID = "transId";
public static final String KEY_NAME = "name";
public static final String KEY_SURNAME = "surname";
public static final String KEY_MOBILE= "mobile";
public static final String KEY_TYPE = "Type";
public static final String KEY_DATETIME = "DateTime";
public static final String KEY_AMOUNT = "Amount";
public static final String KEY_BALANCE = "Balance";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "radicalfinance";
private static final String DATABASE_CLIENTSTable = "clientstable";
private static final String DATABASE_TRANSACTIONS = "TransactionsTable";
private static final String DATABASE_CLIENTSBALANCE = "ClientsBalanceTable";
private static final int DATABASE_VERSION = 1;
//Creating the database radicalfinance
//CREATING CLIENTSTable
private static final String DATABASE_CREATE_CLIENTSTABLE =
"create table clientstable (_id integer primary key autoincrement, "
+ "name text not null, surname text not null, "
+ "mobile integer not null);";
//CREATING TransactionsTable
private static final String DATABASE_CREATE_TRANSACTIONSTABLE =
"create table TransactionsTable (_id integer primary key autoincrement, "
+ "transId integer,"
+ "Type boolean not null, DateTime text not null, "
+ "Amount long not null);";
//CREATING ClientsBalanceTable
private static final String DATABASE_CREATE_CLIENTSBALANCETABLE =
"create table ClientsBalanceTable (_id integer primary key autoincrement, "
+ "Balance long not null); ";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
public class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(DATABASE_CREATE_CLIENTSTABLE);
db.execSQL(DATABASE_CREATE_TRANSACTIONSTABLE);
db.execSQL(DATABASE_CREATE_CLIENTSBALANCETABLE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS clientstable");
onCreate(db);
}
}
//methods for opening and closing the database, as well as the methods for adding/editing/deleting rows in the table.
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a client and his info into the database---
public long insertClient(String name, String surname, String mobile)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_SURNAME, surname);
initialValues.put(KEY_MOBILE, mobile);
return db.insert(DATABASE_CLIENTSTable, null, initialValues);
}
public long insertClientTransaction(String transId, String Type, String DateTime, String Amount)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_TRANSID, transId);
initialValues.put(KEY_TYPE, Type);
initialValues.put(KEY_DATETIME, DateTime);
initialValues.put(KEY_AMOUNT, Amount);
return db.insert(DATABASE_TRANSACTIONS, null, initialValues);
}
public long insertClientBalance(String Balance)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_BALANCE, Balance);
return db.insert(DATABASE_CLIENTSBALANCE, null, initialValues);
}
//---deletes a particular client---
public boolean deleteClient(long clientId)
{
return db.delete(DATABASE_CLIENTSTable,KEY_CLIENTID + "=" + clientId, null) > 0;
}
//---retrieves all the clients---
public Cursor getAllClients()
{
return db.query(DATABASE_CLIENTSTable, new String[] {
KEY_CLIENTID,
KEY_NAME,
KEY_SURNAME,
KEY_MOBILE},
null,
null,
null,
null,
null);
}
//querying TransactionsTable
public Cursor getAllTransactionsRecords() {
return db.query(DATABASE_TRANSACTIONS, new String[] {
KEY_TRANSID,
KEY_TYPE,
KEY_DATETIME,
KEY_AMOUNT},
null,
null,
null,
null,
null);
}
//made comments will be taken care of i.e the clientsbalanceRecords
//querying clientsbalancetable
//public Cursor getAllBalanceRecords() {
//return db.query(DATABASE_CLIENTSBALANCE, new String[] {
//KEY_BALANCE},
//null,
//null);
//}
//---retrieves a particular client---
public Cursor getClient(long clientId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_CLIENTSTable, new String[] {
KEY_CLIENTID,
KEY_NAME,
KEY_SURNAME,
KEY_MOBILE
},
KEY_CLIENTID + "=" + clientId,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---updates a client's details---
public boolean updateClient(long clientId, String name,
String surname, String mobile)
{
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_SURNAME, surname);
args.put(KEY_MOBILE, mobile);
return db.update(DATABASE_CLIENTSTable, args,
KEY_CLIENTID + "=" + clientId, null) > 0;
}
public boolean updateTransactions(long clientId, long transId, String Type,
String DateTime, long Amount)
{
ContentValues args = new ContentValues();
args.put(KEY_TRANSID, transId);
args.put(KEY_TYPE, Type);
args.put(KEY_DATETIME, DateTime);
args.put (KEY_AMOUNT, Amount);
return db.update(DATABASE_TRANSACTIONS, args,
KEY_CLIENTID + "=" + clientId, null) > 0;
}
public SQLiteDatabase getWritableDatabase() {
// TODO Auto-generated method stub
return null;
}
}
然后这是我的 ClientsActivity 类
package com.android.ideos;
import android.app.ListActivity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.CursorAdapter;
import android.widget.ListAdapter;
import android.widget.Toast;
public class ClientsActivity extends ListActivity {
protected DBAdapter db;
protected CursorAdapter dataSource;
protected ListAdapter adapter;
//private static final String columns[] = { "name", "surname"};
//private static final String TAGG = "ClientsActivity";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
db = new DBAdapter(this);
/*DataBaseHelper helper = new DataBaseHelper(this);
db = helper.getWritableDatabase();
Cursor data = db.query("clientstable", columns,
null, null, null, null, null);
dataSource = new SimpleCursorAdapter(this,
R.layout.clients, data, columns,
new int[] { R.id.name, R.id.surname });
setListAdapter(dataSource);*/
db.open();
Long rowID = db.insertClient("Adera", "Dan", "0727858191");
db.close();
displayclients(rowID);
}
private void displayclients(long clientId)
**{
// TODO Auto-generated method stub
db.open();
Cursor results = db.getClient(clientId);
if (results.moveToFirst())
{
Toast.makeText(this, "Name: "+results.getString(1)+" "+results.getString(2), Toast.LENGTH_LONG).show();
}**
}
//calls the content menu layout
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater myMenuInflater = getMenuInflater();
myMenuInflater.inflate(R.menu.menu, menu);
return true;
}
// the layout of the menu as seen in the menu.xml file
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// TODO Auto-generated method stub
switch(item.getItemId())
{
// the menu button New Client and the functionality code will be implemented here.
case(R.id.menu_new_client):
Toast.makeText(this, "New client", Toast.LENGTH_LONG).show();
break;
// the menu button: Edit, and the functionality code will be implemented here.
case(R.id.menu_edit):
Toast.makeText(this, "Edit", Toast.LENGTH_LONG).show();
break;
// the menu button: DElete, and the functionality code will be implemented here.
case(R.id.menu_delete):
Toast.makeText(this, "Delete", Toast.LENGTH_LONG).show();
break;
// the menu button: Search, and the functionality code will be implemented here.
case(R.id.menu_search):
Toast.makeText(this, "Search", Toast.LENGTH_LONG).show();
break;
}
return true;
}
}
最佳答案
我在任何地方都看不到您通过 ListAdapter (CursorAdapter) 将数据库光标分配给 ListView。
我认为您需要完成所有 3 项谷歌记事本教程，但即使只是 Notepad1 教程也解释了如何将 SimpleCursorAdapter 链接到 ListView。看这个tutorial并特别注意 fillData() 方法
private void fillData() {
// Get all of the notes from the database and create the item list
Cursor c = mDbHelper.fetchAllNotes();
startManagingCursor(c);
String[] from = new String[] { NotesDbAdapter.KEY_TITLE };
int[] to = new int[] { R.id.text1 };
// Now create an array adapter and set it to display using our row
SimpleCursorAdapter notes =
new SimpleCursorAdapter(this, R.layout.notes_row, c, from, to);
setListAdapter(notes);
}
希望对你有帮助
关于android - 如何在 ListView 中显示数据库中的数据？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5717732/