[Kotlin] by lazy

MainActivity.kt

package com.jwsoft.kotlinproject

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log

class MainActivity : AppCompatActivity() {

    private val lazy: String by lazy {
        Log.e("", "called lazy")
        "lazy"
    }

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

        Log.e("", "Before call lazy")
        Log.e("", lazy)
        Log.e("", "After call lazy")
        Log.e("", lazy)
    }

}

val 에서만 사용 가능

 

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