Mastering delays in Android

TestClass.kt

class TestClass(
    private val context: Context,
) {

    private val handler = Handler(Looper.getMainLooper())
    private var runnable: Runnable? = null

    fun onResume() {
        runnable = Runnable {
            Toast.makeText(context, "Hello, Medium", Toast.LENGTH_LONG).show()
        }.also { handler.postDelayed(it, 1_000) }
    }

    fun onPause() {
        runnable?.let { handler.removeCallbacks(it) }
        runnable = null
    }
}