Activity Random code not work and force close

In my previous question it is because the value make the activity not opened so i changed to new code but it still force close

i was using bluestack as emulator so there is no Log Cat

this is my code to make random activity

public class menu extends Activity {


    int time = 5, one, two, three, four, five, number;
    RelativeLayout layout1, layout2;
    Button button1; 

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
        WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.menu);

        layout1 =(RelativeLayout)findViewById(R.id.layout1);
        layout2 =(RelativeLayout)findViewById(R.id.layout2);


          new CountDownTimer(5000, 1000) {

          @Override
          public void onFinish() {        
              layout1.setVisibility(View.GONE);
              layout2.setVisibility(View.VISIBLE);
          }

          @Override
          public void onTick(long millisUntilFinished) {
          }
         }.start();  


        button1 = (Button)findViewById(R.id.introbutton1);
        button1.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v){            
            SharedPreferences pref = getSharedPreferences("SavedGame", MODE_PRIVATE); 
            SharedPreferences.Editor editor = pref.edit();      
            editor.putInt("Level", 0);  
            editor.commit();


         // Here, we are generating a random number
         Random generator = new Random();
         number = generator.nextInt(5) + 1; 
         // The '5' is the number of activities

         Class activity = null;

         // Here, we are checking to see what the output of the random was
         switch(number) { 
         // E.g., if the output is 1, the activity we will open is ActivityOne.class


         case 1: 
             activity = activityone.class;

             //to check the activity already opened or not, so he will do this logic

             if(one == 1){
                Random generatorone = new Random();
                number = generatorone.nextInt(5) + 1; 
            }
             break;
         case 2: 
             activity = activitytwo.class;

             if(two== 1){
                Random generatortwo = new Random();
                number = generatortwo.nextInt(5) + 1; 
            }
             break;
         case 3:
             activity = activitythree.class;

            if(three== 1){
                Random generatorthree = new Random();
                number = generatorthree.nextInt(5) + 1; 
            }
             break;
         case 4:
             activity = activityfour.class;

             if(four == 1){
                Random generatorFour = new Random();
                number = generatorFour.nextInt(5) + 1; 
            }                                            

                 editor = pref.edit();
                 // Key,Value
                 editor.putInt("Activity", number);

                 editor.commit();      
                 }
         // We use intents to start activities
         Intent intent = new Intent(getBaseContext(), activity);
         startActivity(intent);
            }
         });
     }

@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 when each activity opened there is a code to make value of the activity == 1 (already opened)

 buttonblack = (Button)findViewById(R.id.buttonblack);
 buttonblack.setOnClickListener(new View.OnClickListener() {

                  public void onClick(View v){
                                level++;
                                SharedPreferences pref = getSharedPreferences("SavedGame", MODE_PRIVATE); 
                                SharedPreferences.Editor editor = pref.edit();      
                                editor.putInt("Lifes", gamelifes);
                                editor.putInt("Level", level); 
                                //sharedpreferences put int values to 1 (the activity already opened) 
                                editor.putInt("One", 1);
                                editor.commit();
                                // Here, we are generating a random number
                                Random generator = new Random();
                                number = generator.nextInt(5) + 1; 
                                // The '5' is the number of activities

                                Class activity = null;

                                // Here, we are checking to see what the output of the random was
                                switch(number) { 
                                // E.g., if the output is 1, the activity we will open is ActivityOne.class



                                            case 1: 
                                                 activity = activityone.class;

                                                 if(one == 1){
                                                    Random generatorone = new Random();
                                                    number = generatorone.nextInt(5) + 1; 
                                                }
                                                 break;
                                             case 2: 
                                                 activity = activitytwo.class;

                                                 if(two== 1){
                                                    Random generatortwo = new Random();
                                                    number = generatortwo.nextInt(5) + 1; 
                                                }
                                                 break;
                                             case 3:
                                                 activity = activitythree.class;

                                                if(three== 1){
                                                    Random generatorthree = new Random();
                                                    number = generatorthree.nextInt(5) + 1; 
                                                }
                                                 break;
                                             case 4:
                                                 activity = activityfour.class;

                                                 if(four == 1){
                                                    Random generatorFour = new Random();
                                                    number = generatorFour.nextInt(5) + 1; 
                                                }                                            
                                                 break;
                                                default:if(level == 5){
                                                    activity = activityfive.class;
                                                    }
                                                    editor = pref.edit();
                                                    // Key,Value
                                                    editor.putInt("Activity", number);

                                                    editor.commit();      
                                                    }
                                           // We use intents to start activities
                                            Intent intent = new Intent(getBaseContext(), activity);
                                            startActivity(intent);
                     }                
             });
    }

There is something missing or wrong with my code that can't make the activity random properly?

can anyone help me to fix this?