How to calculate an average in android?

Question

I've created in my application a few EditText fields and a button. If you put values in the first and in the 2nd EditText fields, when you press the button, the 3rd EditText field shows the sum of the 2 values you entered. That's working fine, but I want to calculate an average. I mean, if I have 4 EditText fields, I want to enter values in 3 (or less) of them and the 4th to show me the average calculating from the sum divided with the number of the values entered. Example: first value: 2, 2nd value: 4 and the average = 2+4=6/2=3. I want to create the case when a EditText field or more is not enter and the application still can calculate the average. Hope you understand what I want. Thanks !

Here is my:

Medii.java:

    package com.cngcnasaud.orar;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.*;

public class Medii extends Activity {

    EditText txtNum1;
    EditText txtNum2;
    EditText txtTotal;
    Button btnCompute;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.medii);

        txtNum1 = (EditText) findViewById(R.id.editText1);
        txtNum2 = (EditText) findViewById(R.id.editText2);
        txtTotal = (EditText) findViewById(R.id.editText3);
        btnCompute = (Button) findViewById(R.id.bmedii);

        btnCompute.setOnClickListener(new ClickButton ());

    }


    private class ClickButton implements Button.OnClickListener{

        @Override
        public void onClick(View v) {

            int x = Integer.parseInt(txtNum1.getText().toString());
            int y = Integer.parseInt(txtNum2.getText().toString());

            int total = (x + y)/2;

            txtTotal.setText(Integer.toString(total));

        }


    }





}

Answer 1

If I understand your question right, you have 3 edittexts and the 4th one should display the average. I haven't tested it so there might be some typos.

String et1 = editText1.getText().toString();


String et2 = editText2.getText().toString();
String et3 = editText3.getText().toString();
int num1 = Integer.parseInt(et1);
 int num2 = Integer.parseInt(et2);
int num3 = Integer.parseInt(et3);
int calculate = num1 + num2 + num3/3;


 int result = calculate;

editText4.setText(" " + result);

Answer 2

Count how many of the fields are not blank, and divide your total by that number. It's probably a good idea to check for blank or not-parsable before you use Integer.parseInt anyways. :)

Answer 3

If I were you I did something different:

A single editText and two buttons: Add number and Calculate.

Every time you hit Add number, capture and put it on an Array.

When you hit Calculate, do a loop to sum the whole numbers in a variable, then do the average as sum_variable/array.lenght.

This way you can sum infinite numbers without creating just a static number of fields.

Good luck!

EDIT: Follow code:

public class MainActivity extends Activity {

public static ArrayList<String> num = new ArrayList<String>();
double sum, res;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    final EditText editTextNum = (EditText)findViewById(R.id.editTextNum);
    Button buttonAdd = (Button)findViewById(R.id.buttonAdd);
    Button buttonCalc = (Button)findViewById(R.id.buttonCalc);
    final TextView textViewRes = (TextView)findViewById(R.id.textViewRes);

    buttonAdd.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
             String numCatch=editTextNum.getText().toString().trim();
                if(numCatch.length() != 0){
                       num.add(numCatch);
                    editTextNum.setText("");
                }
                textViewRes.setText("The average is ");
        }
    });

    buttonCalc.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            DecimalFormat format = new DecimalFormat("#.##");
            for(int i=0;i<num.size();i++){
                sum = Integer.parseInt(num.get(i)) + sum;
            }
            res = sum/num.size();
            textViewRes.setText("The average is "+format.format(res));
            res = 0;
            sum = 0;
            num.clear();
        }
    });
}