Kotlin 스레드(Thread) : 기본구성
- Logcat 에서 확인 할 수 있음

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      activity_main.xml
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<?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">

    <TextView
        android:id="@+id/TV"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Thread Test!!"
        android:textSize="20dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

------------------------------------------------------------------------------------
    MainActivity.kt
------------------------------------------------------------------------------------
class MainActivity : AppCompatActivity() {

    var counter:Int=0
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val testThread= ThreadTest()
        testThread.start()
    }
}

class ThreadTest : Thread() {
    override fun run() {

        var i = 0

        while (i < 10) {
            i += 1
            Log.i("TreadTest", "i = ${i}")
        }

    }
}