다이얼로그일 때 네비게이션바 색깔을 변경

dialog_navigation_bar_color

override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
    val dialog = super.onCreateDialog(savedInstanceState)

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
        setWhiteNavigationBar(dialog)
    }

    return dialog
}

@RequiresApi(api = Build.VERSION_CODES.M)
private fun setWhiteNavigationBar(dialog: Dialog) {
    val window: Window? = dialog.window
    if (window != null) {
        val metrics = DisplayMetrics()
        window.windowManager.defaultDisplay.getMetrics(metrics)

        val dimDrawable = ColorDrawable(Color.TRANSPARENT)
        val navigationBarDrawable = ColorDrawable(Color.WHITE)

        val layers = arrayOf(dimDrawable, navigationBarDrawable)
        val windowBackground = LayerDrawable(layers)
        windowBackground.setLayerInsetTop(1, metrics.heightPixels)

        window.setBackgroundDrawable(windowBackground)
    }
}