MainActivity

package com.caliper.fat;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.RadioGroup;

public class MainActivity extends Activity {
    EditText chest, axilla, tricep, subscapular, abdominal, suprailiac, thigh, age;
    RadioGroup gender;
    double sum, square, result;
    int ageInt;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initialize();
    }

    private void initialize() {
        // TODO Auto-generated method stub
        chest = (EditText)findViewById(R.id.etChest);
        axilla = (EditText)findViewById(R.id.etAxilla);
        tricep = (EditText)findViewById(R.id.etTricep);
        subscapular = (EditText)findViewById(R.id.etSubscapular);
        abdominal = (EditText)findViewById(R.id.etAbdominal);
        suprailiac = (EditText)findViewById(R.id.etSuprailiac);
        thigh = (EditText)findViewById(R.id.etThigh);
        gender = (RadioGroup)findViewById(R.id.rgGender);
        age = (EditText)findViewById(R.id.etAge);
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // TODO Auto-generated method stub
        switch(item.getItemId()){
        case R.id.menuCalculate:
            calculate();
            break;
        }
        return false;
    }

    private void calculate() {
        // TODO Auto-generated method stub
        conversion();

        if(gender.getCheckedRadioButtonId() == R.id.rMale){
            double step1 = 0.0008267 * sum;
            double step2 = 0.00000055 * square;
            double step3 = 0.00028826 * ageInt;
            result = 1.112 - step1 + step2 - step3;
        }
        else if(gender.getCheckedRadioButtonId() == R.id.rFemale){
            double step1 = 0.00046971 * sum;
            double step2 = 0.00000056 * square;
            double step3 = 0.00012828 * ageInt;
            result = 1.097 - step1 + step2 - step3;
        }
        String resultString = Double.toString(result);
        Bundle packet = new Bundle();
        packet.putString("giveResults", resultString);
        Intent a = new Intent(MainActivity.this, Display.class);
        startActivity(a);
    }

    private void conversion() {
        // TODO Auto-generated method stub
        String chestString = chest.getText().toString();
        int chestInt = Integer.parseInt(chestString);
        String axillaString = axilla.getText().toString();
        int axillaInt = Integer.parseInt(axillaString);
        String tricepString = tricep.getText().toString();
        int tricepInt = Integer.parseInt(tricepString);
        String subscapularString = subscapular.getText().toString();
        int subscapularInt = Integer.parseInt(subscapularString);
        String abdominalString = abdominal.getText().toString();
        int abdominalInt = Integer.parseInt(abdominalString);
        String suprailiacString = suprailiac.getText().toString();
        int suprailiacInt = Integer.parseInt(suprailiacString);
        String thighString = thigh.getText().toString();
        int thighInt = Integer.parseInt(thighString);
        String ageString = age.getText().toString();
        ageInt = Integer.parseInt(ageString);
        sum = chestInt + axillaInt + tricepInt + subscapularInt + abdominalInt + suprailiacInt + thighInt;
        square = sum*sum;
    }

}