Android: Juego de Matemáticas

Como práctica hice este pequeño programa que intenta ser un juego de matemáticas. Operaciones básicas de suma, resta, multiplicación y división, son generadas al azar con la respuesta válida y dos respuestas incorrectas. Cada respuesta correcta acumula un punto.

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;

import com.example.mytoolbox.utilities.NumberUtilities;

public class MathRallyActivity extends Activity implements OnClickListener {
 
 public enum Operation {
  SUM, DIVISION, MULTIPLICATION, SUBSTRACT  
 }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_math_rally);
        
        Button buttonOption1 = (Button) findViewById(R.id.buttonMath1);
        Button buttonOption2 = (Button) findViewById(R.id.buttonMath2);
        Button buttonOption3 = (Button) findViewById(R.id.buttonMath3);
        ImageButton buttonHome = (ImageButton) findViewById(R.id.imageButtonHome);
        
        buttonOption1.setOnClickListener(this);
        buttonOption2.setOnClickListener(this);
        buttonOption3.setOnClickListener(this);
        buttonHome.setOnClickListener(this);
        
        createOperation();        
    }
    
    private void createOperation() {
     Operation operation = generateRandOperation();
     
     int operand1 = NumberUtilities.generateRandNumber(2, 100);
     int operand2 = NumberUtilities.generateRandNumber(2, 100);
     
     String operationText = String.valueOf(operand1) + " " +
       getOperationString(operation) + " " + String.valueOf(operand2) + "?";
     
     TextView textViewOperation = (TextView) findViewById(R.id.textViewOperation);
     textViewOperation.setText(operationText);
     float rightValue = calculateRightValue(operation, operand1, operand2);
     
     rightBox = NumberUtilities.generateRandNumber(1, 3);
     float randWrongValue1 = NumberUtilities.generateRandNumber(2);
     float randWrongValue2 = NumberUtilities.generateRandNumber(2);
     
     Button buttonOption1 = (Button) findViewById(R.id.buttonMath1);
        Button buttonOption2 = (Button) findViewById(R.id.buttonMath2);
        Button buttonOption3 = (Button) findViewById(R.id.buttonMath3);
     
     switch (rightBox) {
      case 0:
       buttonOption1.setText(String.valueOf(rightValue));
       buttonOption2.setText(String.valueOf(randWrongValue1));
       buttonOption3.setText(String.valueOf(randWrongValue2));
       break;
      case 1:
       buttonOption2.setText(String.valueOf(rightValue));
       buttonOption1.setText(String.valueOf(randWrongValue1));
       buttonOption3.setText(String.valueOf(randWrongValue2));
       break;
      case 2:
       buttonOption3.setText(String.valueOf(rightValue));
       buttonOption1.setText(String.valueOf(randWrongValue1));
       buttonOption2.setText(String.valueOf(randWrongValue2));
       break;
     }     
    }
    
    private float calculateRightValue(Operation oper, int operand1, int operand2) {
     float calculation = 0;
     
     if (oper == Operation.SUM) {
      calculation = operand1 + operand2;
     } else if (oper == Operation.MULTIPLICATION) {
      calculation = operand1 * operand2;
     } else if (oper == Operation.SUBSTRACT) {
      calculation = operand1 - operand2;
     } else if (oper == Operation.DIVISION) {
      calculation = operand1 / operand2;
     }
     
     return calculation;
    }
    
    private String getOperationString(Operation oper) {
     String operationText = "";
     if (oper == Operation.SUM) {
      operationText = "+";
     } else if (oper == Operation.MULTIPLICATION) {
      operationText = "*";
     } else if (oper == Operation.SUBSTRACT) {
      operationText = "-";
     } else if (oper == Operation.DIVISION) {
      operationText = "/";
     }
     return operationText;
    }
    
    private Operation generateRandOperation() {
     int rand = NumberUtilities.generateRandNumber(1, 4);
     Operation operation = null;
     
     switch(rand) {
      case 0:
       operation = Operation.SUM;
       break;
      case 1:
       operation = Operation.DIVISION;
       break;
      case 2:
       operation = Operation.MULTIPLICATION;
       break;
      case 3:
       operation = Operation.SUBSTRACT;
       break;
     }
     return operation;
    }
  
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_math_rally, menu);
        return true;
    }

 @Override
 public void onClick(View view) {
  boolean correct = false;
  boolean play = true;
  
  switch(view.getId()) {
   case R.id.buttonMath1:
    if (rightBox == 0) {
     correct = true;
    }
    break;
   case R.id.buttonMath2:
    if (rightBox == 1) {
     correct = true;
    }
    break;
   case R.id.buttonMath3:
    if (rightBox == 2) {
     correct = true;
    }
    break;
   case R.id.imageButtonHome:
    startActivity(new Intent(MathRallyActivity.this, ChooseActivity.class));
    play = false;
    break;
  }
  if (correct) {
   points++;
   updateScore();
  } if(play) {
   createOperation();
  }
 }
 
 private void updateScore() {
  EditText editText = (EditText) findViewById(R.id.editTextPoints);
  editText.setText(String.valueOf(points));
 }

 private int rightBox;
 private int points;
}