我创建了一个DB Adapter类，它应该创建两个名为Users_Details和Creditcard_Details的表。但是，当我导出并检查使用SQLite Browser创建的数据库时，我发现只创建了前一个表。我无法理解造成这种情况的原因。 有人可以建议或帮我调试这个问题吗？
以下是数据库适配器的代码：
package com.androidbook.LoginForm;
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;
public class DBAdapter {
/*------------------------User Details ---------------------------------*/
public static Cursor d;
public static final String KEY_ROWID = "_id";
public static final String KEY_Name = "name";
public static final String KEY_Username = "username";
public static final String KEY_Password = "password";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "Wallet";
private static final String DATABASE_TABLE = "User_Details";
/*------------------------Credit Cards Table----------------------*/
private static final String KEY_CCID = "_ccid";
private static final String KEY_CCUNAME= "cuname";
private static final String KEY_CCNO = "ccno";
private static final String KEY_CVV = "cvvno";
private static final String EXP_DATE = "expdate";
private static final String CREDITCARDS_TABLE = "Creditcard_Details";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE =
"create table"+ DATABASE_TABLE + " ( " + KEY_ROWID + " integer primary key autoincrement, "
+ KEY_Name + " text not null, " + KEY_Username + " text not null, "
+ KEY_Password + " text not null);";
private static final String CCTABLE_CREATE = "create table " +
CREDITCARDS_TABLE + " (" + KEY_CCID +
" integer primary key autoincrement, " +
KEY_CCUNAME + "text not null, " + KEY_CCNO + " text not null, " + KEY_CVV + " text not null, " + EXP_DATE + " text not null);";
/*---------------------Create Credit Card Table -------------------------------*/
/* private static final String CCTABLE_CREATE =
"create table"+ CREDITCARDS_TABLE + " ( " + KEY_CCID + " integer primary key , "
+ KEY_CCUNAME + " text not null, " + KEY_CCNO + " ccno text not null, "
+ KEY_CVV + " text not null, " + EXP_DATE + " text not null);";//+ "FOREIGN KEY(_ccid) REFERENCES User_Details(_id))";
*/
private final Context context;
public DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(DATABASE_CREATE);
db.execSQL(CCTABLE_CREATE);
}
@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 titles");
onCreate(db);
}
}
public int Login(String username,String password)
{
try
{
Cursor c = null;
c = db.rawQuery("select * from User_Details where username =" + "\""+ username + "\""+" and password="+ "\""+ password + "\"", null);
c.moveToFirst();
//Toast.makeText(DBAdapter.this, "correct"+" "+c,Toast.LENGTH_LONG).show();
d= c;//CCview(tempid);
return c.getCount();
}
catch(Exception e)
{
e.printStackTrace();
}
return 0;
}
//-----------------------Display Credit Card -----------------------------
/* public int Getid(String tempid)
{ Cursor c;
c = db.rawQuery("select id from User_Details where username ="
+ "\""+ username + "\"", null);
return Integer.parseInt(c.getString(0));
}*/
public Cursor CCview(long menuid)throws SQLException
{
Cursor mCursor =
db.query(true, CREDITCARDS_TABLE, new String[] {
KEY_CCID,
KEY_CCUNAME,
KEY_CCNO,
KEY_CVV,
EXP_DATE,
},
KEY_CCID + "=" + menuid,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//--------------------Entries into Credit Card Table------------------------------------
//---insert a title into the database---
public long insertCreditcard( String j, String k, String l, String date)
{
ContentValues creditValues = new ContentValues();
// creditValues.put(KEY_CCID, i);
creditValues.put(KEY_CCUNAME, j);
creditValues.put(KEY_CCNO, k);
creditValues.put(KEY_CVV, l);
creditValues.put(EXP_DATE, date);
return db.insert(CREDITCARDS_TABLE, null, creditValues);
}
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a title into the database---
public long insertTitle(String name, String username, String password)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_Name, name);
initialValues.put(KEY_Username, username);
initialValues.put(KEY_Password, password);
return db.insert(DATABASE_TABLE, null, initialValues);
}
//---deletes a particular title---
public boolean deleteTitle(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//---retrieves all the titles---
public Cursor getAllTitles()
{
return db.query(DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_Name,
KEY_Username,
KEY_Password},
null,
null,
null,
null,
null);
}
//---retrieves a particular title---
public Cursor getTitle(long rowId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_Name,
KEY_Username,
KEY_Password
},
KEY_ROWID + "=" + rowId,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---updates a title---
public boolean updateTitle(long rowId, String name,
String username, String password)
{
ContentValues args = new ContentValues();
args.put(KEY_Name, name);
args.put(KEY_Username, username);
args.put(KEY_Password, password);
return db.update(DATABASE_TABLE, args,
KEY_ROWID + "=" + rowId, null) > 0;
}
}
答案 0 :(得分：0)
尝试更改DATABASE_VERSION数字。我建议这是因为你可能在开发期间有一个表（并且db_ver是1），然后在代码中添加了第二个表，但它没有出现（因此这个帖子）。
或卸载+重新安装即可实现此目的。