I've a problem!
I've a quiz app with few questions what generated from the code, but I make an Activity, where I can put some questions to the other in an SQLite Db from the running program.
I write an insert code, but when I load the SaveDataActivity, fill the form, and press the Save Button, the program crashed.
I don't know how fix my code, I tired a many tricks.
Here is my Activity code:
package com.example.jvstgs;
import android.support.v7.app.ActionBarActivity;
import android.text.TextUtils;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class SaveDataActivity extends ActionBarActivity {
DbHelper dbase;
EditText kerdes, valaszA, valaszB, valaszC, valaszD, helyesValasz;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_save_data);
kerdes = (EditText) findViewById(R.id.editText5);
valaszA = (EditText) findViewById(R.id.editText1);
valaszB = (EditText) findViewById(R.id.editText2);
valaszC = (EditText) findViewById(R.id.editText3);
valaszD = (EditText) findViewById(R.id.editText4);
helyesValasz = (EditText) findViewById(R.id.editText6);
openDb();
Button button = (Button) findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(SaveDataActivity.this, ResultActivity.class);
startActivity(intent);
finish();
}
});
Button button2 = (Button) findViewById(R.id.Button01);
button2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(SaveDataActivity.this, ResultActivity.class);
startActivity(intent);
finish();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.save_data, menu);
return true;
}
private void openDb()
{
dbase = new DbHelper(this);
dbase.open();
}
public void onClick_mentes(View v){
if (!TextUtils.isEmpty(kerdes.getText().toString())){
dbase.insertRow(null, kerdes.getText().toString(), valaszA.getText().toString()
, valaszB.getText().toString(), valaszC.getText().toString()
, valaszD.getText().toString());
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
... and my DbHelper, where controll the Db:
package com.example.jvstgs;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
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.widget.EditText;
public class DbHelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "triviaQuiz";
// tasks table name
private static final String TABLE_QUEST = "quest";
// tasks Table Columns names
private static final String KEY_ID = "id";
private static final String KEY_QUES = "question";
private static final String KEY_ANSWER = "answer";
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 static final String KEY_OPTD= "optd"; //option d
private SQLiteDatabase dbase;
public DbHelper(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, "+KEY_OPTD+" TEXT)";
db.execSQL(sql);
addQuestions();
//db.close();
}
private void addQuestions()
{
Question q1=new Question("Mire jó a UPS?"
,"Vészenegergiaforrás", "Hálózat típus", "TV-netes rendszer","Csatlakozó", "Vészenegergiaforrás");
this.addQuestion(q1);
Question q2=new Question("Merevlemezen az adatok ... helyezkednek el. "
, "sugárirányban", "fentről lefelé, függőlegesen", "koncentrikus körön", "spirális körön", "koncentrikus körön");
this.addQuestion(q2);
Question q3=new Question("Mi a VGA kártya teljes neve?"
,"Video Games Adapter", "Video Graphic Array","Video Graphic Adapter","Video Gambling Automat", "Video Graphic Array");
this.addQuestion(q3);
Question q4=new Question("Melyik a kakkuktojás?"
,"Bigtorony", "Slimház", "Babyház","Miditorony", "Bigtorony");
this.addQuestion(q4);
Question q5=new Question("Melyik nem interpretált nyelv" +
" a felsoroltak közül?","Ruby","BASIC","Perl","Python","BASIC");
this.addQuestion(q5);
Question q6=new Question("Mennyivel egyenlő 1 petabyte?"
,"100MB","1000TB","1024TB","1024GB","1024TB");
this.addQuestion(q6);
Question q7=new Question("Melyik operációs rendszer rendelkezett először aero kinézettel?"
,"Linux Mint","Windows Vista","Mac OS-X 10.2","Windows 7","Windows Vista");
this.addQuestion(q7);
Question q8=new Question("Hogy hívták az első kompletten legyártott PC-t?"
,"Z71","IBM PC XT","Commodore 64","Apple II","Apple II");
this.addQuestion(q8);
Question q9=new Question("Minek a mértékegysége a baud?"
,"Adatátvitel sebesség","Busz sebesség","A nyomtató képfelbontása","Az adattípusú fájl mérete","Adatátvitel sebesség");
this.addQuestion(q9);
Question q10=new Question("Mekkora az XT busz adatszélessége?"
,"8 bit","32 bit","64 bit","16 bit","8 bit");
this.addQuestion(q10);
}
@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());
values.put(KEY_OPTD, quest.getOPTD());
// Inserting Row
dbase.insert(TABLE_QUEST, null, values);
}
public List<Question> getAllQuestions() {
List<Question> quesList = new ArrayList<Question>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_QUEST + " ORDER BY RANDOM()";
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));
quest.setOPTD(cursor.getString(6));
quesList.add(quest);
} while (cursor.moveToNext());
}
// return quest list
return quesList;
}
public int getrowCount() {
String countQuery = "SELECT * FROM " + TABLE_QUEST;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
int cnt = cursor.getCount();
cursor.close();
return cnt;
}
public DbHelper open() {
SQLiteDatabase db = this.getWritableDatabase();
return this;
}
public void close(){
this.close();
}
public long insertRow(String kerdes, String valaszA, String valaszB
, String valaszC, String valaszD, String helyesValasz) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_QUES, kerdes);
initialValues.put(KEY_OPTA, valaszA);
initialValues.put(KEY_OPTB, valaszB);
initialValues.put(KEY_OPTC, valaszC);
initialValues.put(KEY_OPTD, valaszD);
initialValues.put(KEY_ANSWER, helyesValasz);
return dbase.insert(TABLE_QUEST, null, initialValues);
}
}
onClick_mentes is an onclick method, where I give the data to the DbHelper by insertRow, but its crashed, when I'm testing.
Where I wrong it && how fix it? :/
////EDITED//// My LogCat:
06-18 11:38:46.964: E/AndroidRuntime(615): FATAL EXCEPTION: main
06-18 11:38:46.964: E/AndroidRuntime(615): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.jvstgs/com.example.jvstgs.ResultActivity}: java.lang.NullPointerException
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread.access$600(ActivityThread.java:130)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.os.Handler.dispatchMessage(Handler.java:99)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.os.Looper.loop(Looper.java:137)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread.main(ActivityThread.java:4745)
06-18 11:38:46.964: E/AndroidRuntime(615): at java.lang.reflect.Method.invokeNative(Native Method)
06-18 11:38:46.964: E/AndroidRuntime(615): at java.lang.reflect.Method.invoke(Method.java:511)
06-18 11:38:46.964: E/AndroidRuntime(615): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
06-18 11:38:46.964: E/AndroidRuntime(615): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
06-18 11:38:46.964: E/AndroidRuntime(615): at dalvik.system.NativeStart.main(Native Method)
06-18 11:38:46.964: E/AndroidRuntime(615): Caused by: java.lang.NullPointerException
06-18 11:38:46.964: E/AndroidRuntime(615): at com.example.jvstgs.ResultActivity.onCreate(ResultActivity.java:25)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.Activity.performCreate(Activity.java:5008)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
06-18 11:38:46.964: E/AndroidRuntime(615): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
06-18 11:38:46.964: E/AndroidRuntime(615): ... 11 more
///EDITED 2/// My ResultActivity:
package com.example.jvstgs;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.widget.Button;
import android.widget.RatingBar;
import android.widget.TextView;
import android.view.View;
import android.view.View.OnClickListener;
public class ResultActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_result);
//get rating bar object
RatingBar bar=(RatingBar)findViewById(R.id.ratingBar1);
bar.setNumStars(5);
bar.setStepSize(0.5f);
//get text view
TextView t=(TextView)findViewById(R.id.textResult);
//get score
Bundle b = getIntent().getExtras();
int score= b.getInt("score");
//display score
bar.setRating(score);
switch (score)
{
case 1:
case 2: t.setText("Horrible!!!!");
break;
case 3:
case 4:t.setText("So so....");
break;
case 5:t.setText("It's a nice try!");
break;
}
/// Try again the game bring to the first Activity
Button button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(ResultActivity.this, QuizActivity.class);
startActivity(intent);
finish();
}
});
// Its bring to the SaveDataActivity where Somebody can put the questions to the Db.
Button button2 = (Button) findViewById(R.id.button2);
button2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(ResultActivity.this, SaveDataActivity.class);
startActivity(intent);
finish();
}
});
// Exit from the application
Button button4 = (Button) findViewById(R.id.button4);
button4.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
finish();
System.exit(0);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.result, menu);
return true;
}
}
Thanks for the help!
