[코틀린] 간단 계산기

 

MainActivity.kt

package com.example.helloandroid
 
import android.graphics.Color
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.TextView
 
class MainActivity : AppCompatActivity() {
    lateinit var edit1 : EditText;  lateinit var edit2 : EditText
    lateinit var btnAdd : Button;   lateinit var btnSub : Button
    lateinit var btnMul : Button;   lateinit var btnDiv : Button
    lateinit var TextResult : TextView
 
    lateinit var num1 : String;     lateinit var num2 : String
    var result : Int? = null
 
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
 
        title = "초간단 계산기"
 
        edit1 = findViewById<EditText>(R.id.Edit1)
        edit2 = findViewById<EditText>(R.id.Edit2)
        btnAdd = findViewById<Button>(R.id.BtnAdd)
        btnSub = findViewById<Button>(R.id.BtnSub)
        btnMul = findViewById<Button>(R.id.BtnMul)
        btnDiv = findViewById<Button>(R.id.BtnDiv)
        TextResult = findViewById<TextView>(R.id.TextResult)
 
        btnAdd.setOnTouchListener { view, motionEvent ->
            num1 = edit1.text.toString()
            num2 = edit2.text.toString()
            result = Integer.parseInt(num1) + Integer.parseInt(num2)
            TextResult.text = "계산결과 : " + result.toString()
            false
        }
        btnSub.setOnTouchListener { view, motionEvent ->
            num1 = edit1.text.toString()
            num2 = edit2.text.toString()
            result = Integer.parseInt(num1) - Integer.parseInt(num2)
            TextResult.text = "계산결과 : " + result.toString()
            false
        }
        btnMul.setOnTouchListener { view, motionEvent ->
            num1 = edit1.text.toString()
            num2 = edit2.text.toString()
            result = Integer.parseInt(num1) * Integer.parseInt(num2)
            TextResult.text = "계산결과 : " + result.toString()
            false
        }
        btnDiv.setOnTouchListener { view, motionEvent ->
            num1 = edit1.text.toString()
            num2 = edit2.text.toString()
            result = Integer.parseInt(num1) / Integer.parseInt(num2)
            TextResult.text = "계산결과 : " + result.toString()
            false
        }
    }
}
 

 

 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:padding="30dp"
    tools:context=".MainActivity">
 
        <EditText
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/Edit1"
            android:layout_margin="10dp"
            android:hint="숫자1"
            />
        <EditText
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/Edit2"
            android:layout_margin="10dp"
            android:hint="숫자2"
            />
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/BtnAdd"
            android:layout_margin="10dp"
            android:text="더하기"/>
 
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/BtnSub"
            android:layout_margin="10dp"
            android:text="빼기"/>
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/BtnMul"
            android:layout_margin="10dp"
            android:text="곱하기"/>
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/BtnDiv"
            android:layout_margin="10dp"
            android:text="나누기"/>
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/TextResult"
            android:textSize="30dp"
            android:textColor="#ff0000"
            android:layout_margin="10dp"
            android:text="계산 결과 : "/>
</LinearLayout>