Android: Java code for Tip Calculator

// Created by Bill Rosener

package com.example.tipCalculator;


import com.example.tipCalculator.R;

import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;


public class TipCalculator extends Activity {
  EditText theInitialAmount;
  TextView theTotalAmount, theTipAmount;
  Button ButtonPoorService, ButtonAverageService, ButtonExcellentService;
  @Override

  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    theInitialAmount = (EditText) findViewById(R.id.initialAmount);
    theTipAmount = (TextView) findViewById(R.id.tipAmount);
    theTipAmount.setText("0.00");
    theTotalAmount = (TextView) findViewById(R.id.totalAmount);
    theTotalAmount.setText("0.00");

    ButtonPoorService = (Button) findViewById(R.id.poorService);
    ButtonPoorService.setOnClickListener(new View.OnClickListener() {
       public void onClick(View v) {
         calculatePoorService(theInitialAmount.getText());
        }
     });

    ButtonAverageService = (Button) findViewById(R.id.averageService);
    ButtonAverageService.setOnClickListener(new View.OnClickListener() {
       public void onClick(View v) {
         calculateAverageService(theInitialAmount.getText());
        }
     });


    ButtonExcellentService = (Button) findViewById(R.id.excellentService);
    ButtonExcellentService.setOnClickListener(new View.OnClickListener() {
       public void onClick(View v) {
         calculateExcellentService(theInitialAmount.getText());
        }
     });

    
   }

  
    
   protected void calculatePoorService(Editable first) {
	 float temp, tip, total;
	 double roundedTip;
     temp = Float.parseFloat(first.toString());
     tip = (float) (temp * 0.10);
     roundedTip = Math.round(tip*100)/100.0d;
     total = (float) (temp + roundedTip);
     theTipAmount.setText(String.valueOf(roundedTip));
     theTotalAmount.setText(String.valueOf(total));
   }

   protected void calculateAverageService(Editable first) {
	 float temp, tip, total;
	 double roundedTip;
	 temp = Float.parseFloat(first.toString());
	 tip = (float) (temp * 0.15);
	 roundedTip = Math.round(tip*100)/100.0d;
	 total = (float) (temp + roundedTip);
	 theTipAmount.setText(String.valueOf(roundedTip));
	 theTotalAmount.setText(String.valueOf(total));
   }

   protected void calculateExcellentService(Editable first) {
     float temp, tip, total;
	 double roundedTip;
	 temp = Float.parseFloat(first.toString());
	 tip = (float) (temp * 0.20);
	 roundedTip = Math.round(tip*100)/100.0d;
	 total = (float) (temp + roundedTip);
	 theTipAmount.setText(String.valueOf(roundedTip));
	 theTotalAmount.setText(String.valueOf(total));
   } 
   
}