SettingsPanel.cs

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using DG.Tweening;
using UnityEngine.EventSystems;

public class SettingsPanel : MonoBehaviour {

	RectTransform _aRect;
	bool _isHidden = true;
	float _panelHeight;
    Sequence _hidePanel;

    void Awake ()
    {
		_aRect = GetComponent<RectTransform>();
		_panelHeight = GetComponentInParent<Canvas>().rectTransform().sizeDelta.y;
    }

    void Start ()
    {
		_aRect.sizeDelta = new Vector2(450.0f, _panelHeight);
		_aRect.anchoredPosition = new Vector2(_aRect.anchoredPosition.x, -_panelHeight);
		_hidePanel = DOTween.Sequence().SetAutoKill(false).Pause();
		_hidePanel.Append(_aRect.DOAnchorPos(new Vector2(_aRect.anchoredPosition.x, 0f), 1.0f).SetEase(Ease.InOutBack));
	}

	public void PanelExposer ()
	{
        if (_isHidden)
		{
			_hidePanel.PlayForward();
		} else {
			_hidePanel.PlayBackwards();
		}
		SoundManager.PlaySoundForSettingsWindow();
		_isHidden = !_isHidden;
	}

    public bool IsPanelHidden () {
        return _isHidden;
    }
}