我有一个名字列，另一个有分数。我每次按下某个按钮时都会尝试更新数据库中的分数，这个按钮会为数据库添加一定数量的分数，但它无法正常工作。我如何从数据库中正确获取数据并进行更新？这与数据库版本有关吗？
谢谢。
数据库类
public class myDbAdapter extends SQLiteOpenHelper{
public static final String DATABASE_NAME = "Castaways.db";
public static final String TABLE_NAME = "Survivor_Table";
public static final String COL_1 = "ID";
public static final String COL_2 = "NAME";
public static final String COL_3 = "MARK";
public myDbAdapter(Context context) {
super(context, DATABASE_NAME, null, 3);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table " + TABLE_NAME +" (ID INTEGER PRIMARY KEY AUTOINCREMENT,NAME TEXT,MARK INTEGER)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
onCreate(db);
}
public boolean addData(String name,int score) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL_2,name);
contentValues.put(COL_3,score);
long result = db.insert(TABLE_NAME,null ,contentValues);
if(result == -1)
return false;
else
return true;
}
public Cursor getData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from "+TABLE_NAME,null);
return res;
}
public Cursor getItemID(String name){
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT " + COL_1 + " FROM " + TABLE_NAME +
" WHERE " + COL_2 + " = '" + name + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
public Cursor getScore(int id){
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT " + COL_3 + " FROM " + TABLE_NAME +
" WHERE " + COL_1 + " = '" + id + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
public void updateName(String newName, int id, String oldName){
SQLiteDatabase db = this.getWritableDatabase();
String query = "UPDATE " + TABLE_NAME + " SET " + COL_2 +
" = '" + newName + "' WHERE " + COL_1 + " = '" + id + "'" +
" AND " + COL_2 + " = '" + oldName + "'";
Log.d(TAG, "updateName: query: " + query);
Log.d(TAG, "updateName: Setting name to " + newName);
db.execSQL(query);
}
public Integer deleteData(String id) {
SQLiteDatabase db = this.getWritableDatabase();
return db.delete(TABLE_NAME, "ID = ?",new String[] {id});
}
public void deleteName(int id, String name){
SQLiteDatabase db = this.getWritableDatabase();
String query = "DELETE FROM " + TABLE_NAME + " WHERE "
+ COL_1 + " = '" + id + "'" +
" AND " + COL_2 + " = '" + name + "'";
Log.d(TAG, "deleteName: query: " + query);
Log.d(TAG, "deleteName: Deleting " + name + " from database.");
db.execSQL(query);
}
public void updateScore(int newScore, int id){
SQLiteDatabase db = this.getWritableDatabase();
String query = "UPDATE " + TABLE_NAME + " SET " + COL_3 +
" = '" + newScore + "' WHERE " + COL_1 + " = '" + id + "'";
Log.d(TAG, "updateScore: query: " + query);
Log.d(TAG, "updateScore: Setting score to " + newScore);
db.execSQL(query);
}
public void updateScore2(int newScore, int id, int oldScore){
SQLiteDatabase db = this.getWritableDatabase();
String query = "UPDATE " + TABLE_NAME + " SET " + COL_3 +
" = '" + newScore + "' WHERE " + COL_1 + " = '" + id + "'" +
" AND " + COL_3 + " = '" + oldScore + "'";
Log.d(TAG, "updateScore: query: " + query);
Log.d(TAG, "updateScore: Setting score to " + newScore);
db.execSQL(query);
}
public void clearData()
{
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_NAME,null,null);
db.close();
}
}
添加积分等级
public class Outcomes extends Activity {
private TextView castname;
myDbAdapter mydb;
private String selectedCastaway;
private int selectedID;
private int points = 0;
private int castscore;
EditCastaway EC = new EditCastaway();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_outcomes);
mydb = new myDbAdapter(this);
//get the intent extra from the ListDataActivity
Intent receivedIntent = getIntent();
//now get the itemID we passed as an extra
selectedID = receivedIntent.getIntExtra("id",-1); //NOTE: -1 is just the default value
//now get the name we passed as an extra
selectedCastaway = receivedIntent.getStringExtra("name");
defineButtons();
castname.setText(selectedCastaway);
castscore = receivedIntent.getIntExtra("score", 0);
}
public void defineButtons()
{
findViewById(R.id.out1).setOnClickListener(buttonClickListener);
findViewById(R.id.out2).setOnClickListener(buttonClickListener);
findViewById(R.id.out3).setOnClickListener(buttonClickListener);
findViewById(R.id.out4).setOnClickListener(buttonClickListener);
findViewById(R.id.out5).setOnClickListener(buttonClickListener);
findViewById(R.id.out6).setOnClickListener(buttonClickListener);
findViewById(R.id.out7).setOnClickListener(buttonClickListener);
findViewById(R.id.out8).setOnClickListener(buttonClickListener);
findViewById(R.id.out9).setOnClickListener(buttonClickListener);
findViewById(R.id.out10).setOnClickListener(buttonClickListener);
findViewById(R.id.out11).setOnClickListener(buttonClickListener);
findViewById(R.id.out12).setOnClickListener(buttonClickListener);
findViewById(R.id.out13).setOnClickListener(buttonClickListener);
findViewById(R.id.out14).setOnClickListener(buttonClickListener);
findViewById(R.id.out15).setOnClickListener(buttonClickListener);
findViewById(R.id.out16).setOnClickListener(buttonClickListener);
findViewById(R.id.out17).setOnClickListener(buttonClickListener);
findViewById(R.id.out18).setOnClickListener(buttonClickListener);
findViewById(R.id.out19).setOnClickListener(buttonClickListener);
findViewById(R.id.out20).setOnClickListener(buttonClickListener);
findViewById(R.id.out21).setOnClickListener(buttonClickListener);
castname = (TextView) findViewById(R.id.castname);
}
private View.OnClickListener buttonClickListener = new View.OnClickListener() {
public void onClick(View v) {
switch (v.getId()) {
case R.id.out1:
points = 15;
toastAdd(points);
/*Cursor data = mydb.getScore(selectedID);
while(data.moveToNext())
{
castscore = data.getInt(0);
}*/
mydb.updateScore2(castscore + points, selectedID, castscore);
castscore = castscore + points;
break;
case R.id.out2:
points = 20;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out3:
points = 5;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out4:
points = 30;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out5:
points = 10;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out6:
points = 5;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out7:
points = 10;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out8:
points = 10;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out9:
points = 15;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out10:
points = 10;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out11:
points = 10;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out12:
points = 15;
toastAdd(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out13:
points = -5;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out14:
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out15:
points = -40;
toastRemoveEliminate(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
if(EC.radbut.isChecked())
{
EC.radbut.toggle();
}
break;
case R.id.out16:
points = -15;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out17:
points = -2;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out18:
points = -7;
toastRemoveEliminate(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out19:
points = 60;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out20:
points = 30;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
case R.id.out21:
points = 10;
toastRemove(points);
mydb.updateScore2(castscore + points,selectedID,castscore);
castscore = castscore + points;
break;
}
}
};
private void toastText(String text)
{
Toast.makeText(this,text, Toast.LENGTH_SHORT).show();
}
private void toastAdd(int points)
{
Toast toast=Toast.makeText(this,points + " points has been added to " + selectedCastaway,Toast.LENGTH_SHORT);
toast.show();
}
private void toastRemove(int points)
{
points = points*-1;
Toast toast=Toast.makeText(this,points + " points has been removed from " + selectedCastaway,Toast.LENGTH_SHORT);
toast.show();
}
private void toastRemoveEliminate(int points)
{
points = points*-1;
Toast toast=Toast.makeText(this,points + " points has been removed from " + selectedCastaway + " This Castaway is now no longer in the game!",Toast.LENGTH_SHORT);
toast.show();
}
}
答案 0 :(得分：0)
在updateName中：
WHERE " + COL_1 + " = '" + id + "'"
id是一个int所以引用是错误的。 应该是：
WHERE " + COL_1 + " = " + id
但是，你的代码是主题代码SQL注入;使用PreparedStatement提高性能和安全性