[Kotlin] BMI 측정기 만들기

 

 

Activity_Main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/heightEditText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginTop="76dp"
        android:layout_marginEnd="16dp"
        android:ems="10"
        android:hint="키"
        android:inputType="textPersonName"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/weightEditText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginTop="136dp"
        android:layout_marginEnd="16dp"
        android:ems="10"
        android:hint="몸무게"
        android:inputType="number"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/resultButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="14dp"
        android:text="결과"
        app:layout_constraintEnd_toEndOf="@+id/weightEditText"
        app:layout_constraintTop_toBottomOf="@+id/weightEditText" />

    <EditText
        android:id="@+id/nameEditText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="16dp"
        android:ems="10"
        android:hint="이름"
        android:inputType="textPersonName"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

 

activity_result.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ResultActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="188dp"
        android:layout_marginBottom="34dp"
        android:text="결과가 표시되는 곳"
        android:textAppearance="@style/TextAppearance.AppCompat.Large"
        app:layout_constraintBottom_toTopOf="@+id/imageView"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="78dp"
        android:layout_height="0dp"
        android:layout_marginBottom="279dp"
        android:tint="@color/teal_700"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView"
        app:srcCompat="@drawable/ic_baseline_sentiment_satisfied_alt_24" />
</androidx.constraintlayout.widget.ConstraintLayout>

 

MainActivity.kt

package com.example.bmi

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import androidx.core.graphics.toColorInt

class MainActivity : AppCompatActivity() {

    lateinit var resultButton: Button
    lateinit var nameEditText: EditText
    lateinit var heightEditText: EditText
    lateinit var weightEditText: EditText

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        resultButton = findViewById<Button>(R.id.resultButton)
        nameEditText=findViewById<EditText>(R.id.nameEditText)
        heightEditText=findViewById<EditText>(R.id.heightEditText)
        weightEditText=findViewById<EditText>(R.id.weightEditText)

        loadData()


        resultButton.setOnClickListener {

            saveData(heightEditText.text.toString().toInt(),weightEditText.text.toString().toInt())
            var intent = Intent(this, ResultActivity::class.java)
            intent.putExtra("height",heightEditText.text.toString())
            intent.putExtra("weight",weightEditText.text.toString())
            intent.putExtra("name",nameEditText.text.toString())

            startActivity(intent)
        }
    }
    private fun saveData(height:Int, weight:Int){
        var pref = this.getPreferences(0)
        var editor = pref.edit()


        editor.putString("KEY_NAME",nameEditText.text.toString()).apply()
        editor.putInt("KEY_HEIGHT",heightEditText.text.toString().toInt()).apply()
        editor.putInt("KEY_WEIGHT",weightEditText.text.toString().toInt()).apply()
    }

    private fun loadData(){
        var pref=this.getPreferences(0)
        var name=pref.getString("KEY_NAME","")
        var height=pref.getInt("KEY_HEIGHT",0)
        var weight=pref.getInt("KEY_WEIGHT",0)


        if(name!="" && height!=0 &&weight !=0){
            nameEditText.setText(name.toString())
            heightEditText.setText(height.toString())
            weightEditText.setText(weight.toString())
        }

    }



}

 

ResultActivity.kt

package com.example.bmi

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.ImageView
import android.widget.TextView
import android.widget.Toast

class ResultActivity : AppCompatActivity() {

    lateinit var resultTextView : TextView
    lateinit var imageView : ImageView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_result)

        resultTextView = findViewById<TextView>(R.id.textView)
        imageView = findViewById<ImageView>(R.id.imageView)
        var height = intent.getStringExtra("height")!!.toInt()
        var weight = intent.getStringExtra("weight")!!.toInt()
        var name = intent.getStringExtra("name")


        var bmi = weight / Math.pow(height / 100.0, 2.0)


        when {
            bmi >= 35 -> resultTextView.text = "고도비만"
            bmi >= 30 -> resultTextView.text = "2단계 비만"
            bmi >= 25 -> resultTextView.text = "1단계 비만"
            bmi >= 23 -> resultTextView.text = "과체중"
            bmi >= 18.5 -> resultTextView.text = "정상"
            else -> resultTextView.text = "저체중"
        }

        when {
            bmi >= 23 ->
                imageView.setImageResource(
                        R.drawable.ic_baseline_sentiment_very_dissatisfied_24)
            bmi > 18.5 ->
                imageView.setImageResource(
                        R.drawable.ic_baseline_sentiment_satisfied_alt_24)
            else ->
                imageView.setImageResource(
                        R.drawable.ic_baseline_mood_bad_24)

        }
        Toast.makeText(this,"$name"+" : "+"$bmi",Toast.LENGTH_SHORT).show()

    }

}