我正在创建一个Android应用程序。
当我尝试编辑添加问题或qid的值时，我正在使用sqlite。在我的android工作室里面。 它没有更新。 旧数据库值为5 + 2;我将所有这些都改为1. 5 + 2。
但是当我尝试在我的android工作室中编辑/修改它时，它不会更新。
什么错了？请帮帮我。
这是我的代码。
package com.example.testing;
import java.util.ArrayList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class QuizHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "mathsone";
// tasks table name
private static final String TABLE_QUEST = "quest";
// tasks Table Columns names
private static final String KEY_ID = "qid";
private static final String KEY_QUES = "question";
private static final String KEY_ANSWER = "answer"; // correct option
private static final String KEY_OPTA = "opta"; // option a
private static final String KEY_OPTB = "optb"; // option b
private static final String KEY_OPTC = "optc"; // option c
private SQLiteDatabase dbase;
public QuizHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
dbase = db;
String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_QUEST + " ( "
+ KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_QUES
+ " TEXT, " + KEY_ANSWER + " TEXT, " + KEY_OPTA + " TEXT, "
+ KEY_OPTB + " TEXT, " + KEY_OPTC + " TEXT)";
db.execSQL(sql);
addQuestion();
// db.close();
}
private void addQuestion() {
Question q1 = new Question("1. 5+2 = ?", "7", "8", "6", "7");
this.addQuestion(q1);
Question q2 = new Question("2. 2+18 = ?", "18", "19", "20", "20");
this.addQuestion(q2);
Question q3 = new Question("3. 10-3 = ?", "6", "7", "8", "7");
this.addQuestion(q3);
Question q4 = new Question("4. 5+7 = ?", "12", "13", "14", "12");
this.addQuestion(q4);
Question q5 = new Question("5. 3-1 = ?", "1", "3", "2", "2");
this.addQuestion(q5);
Question q6 = new Question("6. 0+1 = ?", "1", "0", "10", "1");
this.addQuestion(q6);
Question q7 = new Question("7. 9-9 = ?", "0", "9", "1", "0");
this.addQuestion(q7);
Question q8 = new Question("8. 3+6 = ?", "8", "7", "9", "9");
this.addQuestion(q8);
Question q9 = new Question("9. 1+5 = ?", "6", "7", "5", "6");
this.addQuestion(q9);
Question q10 = new Question("10. 7-5 = ?", "3", "2", "6", "2");
this.addQuestion(q10);
Question q11 = new Question("11. 7-2 = ?", "7", "6", "5", "5");
this.addQuestion(q11);
Question q12 = new Question("12. 3+5 = ?", "8", "7", "5", "8");
this.addQuestion(q12);
Question q13 = new Question("13. 0+6 = ?", "7", "6", "5", "6");
this.addQuestion(q13);
Question q14 = new Question("14. 12-10 = ?", "1", "2", "3", "2");
this.addQuestion(q14);
Question q15 = new Question("15. 12+2 = ?", "14", "15", "16", "14");
this.addQuestion(q15);
Question q16 = new Question("16. 2-1 = ?", "2", "1", "0", "1");
this.addQuestion(q16);
Question q17 = new Question("17. 6-6 = ?", "6", "12", "0", "0");
this.addQuestion(q17);
Question q18 = new Question("18. 5-1 = q?", "4", "3", "2", "4");
this.addQuestion(q18);
Question q19 = new Question("19. 4+2 = 19?", "6", "7", "5", "6");
this.addQuestion(q19);
Question q20 = new Question("20. 5+1 = ?", "6", "7", "5", "6");
this.addQuestion(q20);
Question q21 = new Question("5-4 = ?", "5", "4", "1", "1");
this.addQuestion(q21);
// END
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST);
// Create tables again
onCreate(db);
}
// Adding new question
public void addQuestion(Question quest) {
// SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_QUES, quest.getQUESTION());
values.put(KEY_ANSWER, quest.getANSWER());
values.put(KEY_OPTA, quest.getOPTA());
values.put(KEY_OPTB, quest.getOPTB());
values.put(KEY_OPTC, quest.getOPTC());
// Inserting Row
dbase.insert(TABLE_QUEST, null, values);
}
public ArrayList<Question> getAllQuestions() {
ArrayList<Question> quesList = new ArrayList<Question>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_QUEST;
dbase = this.getReadableDatabase();
Cursor cursor = dbase.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Question quest = new Question();
quest.setID(cursor.getInt(0));
quest.setQUESTION(cursor.getString(1));
quest.setANSWER(cursor.getString(2));
quest.setOPTA(cursor.getString(3));
quest.setOPTB(cursor.getString(4));
quest.setOPTC(cursor.getString(5));
quesList.add(quest);
} while (cursor.moveToNext());
}
// return quest list
return quesList;
}
}
答案 0 :(得分：0)
要使用SQLite更新记录，请使用此 -
首先制作一个ContentValues对象：
AndroidOpenDbHelper openDbHelperObj = new AndroidOpenDbHelper(this);
SQLiteDatabase sqLiteDatabase = openDbHelperObj.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(AndroidOpenDbHelper.COLUMN_NAME_ORIGIN,Origin);
contentValues.put(AndroidOpenDbHelper.COLUMN_NAME_DESTINATION,Destination);
然后使用更新方法，现在应该可以使用：
long affectedRowId = sqLiteDatabase.update(AndroidOpenDbHelper.TABLE_NAME_TEST, contentValues, "_id="+id, null);
希望这会有所帮助!!
答案 1 :(得分：0)
更改版本的值
private static final int DATABASE_VERSION = 3;
并且会更新