android activity의 치명적인 예외

이 android activity가 실행되지 않습니다. 아무도 나를 도울 수 있습니다. 그것은 다음 오류를 보여줍니다. 다른 활동을 시작하려면이 버튼을 클릭하면 실행되지 않습니다.android activity의 치명적인 예외

이 오류를 찾을 수 없습니다.

누구든지 고칠 수 있습니까?

오류 : 치명적인 예외 : 주요

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.testingandroid/com.example.testingandroid.SumsMain}: java.lang.NullPointerException 
07-26 12:57:22.958: E/AndroidRuntime(791): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)

코드

package com.example.testingandroid; 

import android.os.Bundle; 
import android.app.Activity; 
import android.content.Intent; 
import android.view.Menu; 
import android.view.View; 
import android.widget.RadioButton; 

public class SelectTitle extends Activity implements android.view.View.OnClickListener{ 
public int entryNo; 
RadioButton r1;RadioButton r2;RadioButton r3;RadioButton r4; 
RadioButton r5;RadioButton r6;RadioButton r7;RadioButton r8; 
RadioButton r9;RadioButton r10;RadioButton r11;RadioButton r12; 
RadioButton r13; 
int determiner; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_select_title); 
     r1 = (RadioButton) findViewById(R.id.MasteryPack); 
     r2 = (RadioButton) findViewById(R.id.Simplification); 
     r3 = (RadioButton) findViewById(R.id.FractionsandRatios); 
     r4 = (RadioButton) findViewById(R.id.Number); 
     r5 = (RadioButton) findViewById(R.id.Average); 
     r6 = (RadioButton) findViewById(R.id.TimeandWork); 
     r7 = (RadioButton) findViewById(R.id.TimeandDistance); 
     r8 = (RadioButton) findViewById(R.id.Interest); 
     r9 = (RadioButton) findViewById(R.id.Measurement); 
     r10 = (RadioButton) findViewById(R.id.Percentage); 
     r11 = (RadioButton) findViewById(R.id.BoatandTrain); 
     r12 = (RadioButton) findViewById(R.id.Practice); 

     r1.setOnClickListener(this); 
     r2.setOnClickListener(this); 
     r3.setOnClickListener(this); 
     r4.setOnClickListener(this); 
     r5.setOnClickListener(this); 
     r6.setOnClickListener(this); 
     r7.setOnClickListener(this); 
     r8.setOnClickListener(this); 
     r9.setOnClickListener(this); 
     r10.setOnClickListener(this); 
     r11.setOnClickListener(this); 
     r12.setOnClickListener(this); 


    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.select_title, menu); 
     return true; 
    } 

    @Override 
    public void onClick(View v) { 
     switch (v.getId()) { 

     case R.id.MasteryPack: 
      Intent nextScreen = new Intent(getApplicationContext(), SumsMain.class); 

      nextScreen.putExtra("determiner", 1); 
      startActivity(nextScreen); 
      break; 

     case R.id.Simplification: 
      Intent nextScreen1 = new Intent(getApplicationContext(), SumsMain.class); 
      //String "determiner" = null; 
      nextScreen1.putExtra("determiner", 2); 
      startActivity(nextScreen1); 
      break; 

     case R.id.FractionsandRatios: 
      Intent nextScreen2 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen2.putExtra("determiner", 3); 
      startActivity(nextScreen2); 
      break; 

     case R.id.Number: 
      Intent nextScreen3 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen3.putExtra("determiner", 4); 
      startActivity(nextScreen3); 
      break; 

     case R.id.Average: 
      Intent nextScreen4 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen4.putExtra("determiner", 5); 
      startActivity(nextScreen4); 
      break; 

     case R.id.TimeandWork: 
      Intent nextScreen5 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen5.putExtra("determiner", 6); 
      startActivity(nextScreen5); 
      break; 

     case R.id.TimeandDistance: 
      Intent nextScreen6 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen6.putExtra("determiner", 7); 
      startActivity(nextScreen6); 
      break; 

     case R.id.Interest: 
      Intent nextScreen7 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen7.putExtra("determiner", 8); 
      startActivity(nextScreen7); 
      break; 

     case R.id.Measurement: 
      Intent nextScreen8 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen8.putExtra("determiner", 9); 
      startActivity(nextScreen8); 
      break; 

     case R.id.Percentage: 
      Intent nextScreen9 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen9.putExtra("determiner", 10); 
      startActivity(nextScreen9); 
      break; 

     case R.id.BoatandTrain: 
      Intent nextScreen10 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen10.putExtra("determiner", 11); 
      startActivity(nextScreen10); 
      break; 

     case R.id.Practice: 
      Intent nextScreen11 = new Intent(getApplicationContext(), SumsMain.class); 
      nextScreen11.putExtra("determiner", 12); 
      startActivity(nextScreen11); 
      break; 



     }  
    } 

}

출처

2013-07-26 Thennarasu Ravindran

전체 스택 추적을 게시하십시오. – Raghunandan

또한,'SumsMain'의'onCreate()'를 게시하십시오. 오류는 해당 클래스에서 발생할 가능성이 큽니다. – codeMagic

'R.layout.activity_select_title'의 내용을 게시 할 수 있습니까? – Geros