private fun isLoggingIn(isLoggingIn: Boolean) {
        val to = if (isLoggingIn) login_progress else login_text
        val from = if (isLoggingIn) login_text else login_progress
        to.animate().cancel()
        from.animate().cancel()
        AnimationHelper.fadeIn(from).setDuration(150).withEndAction { AnimationHelper.fadeOut(to).start() }
    }