[Serializable]
public class RButton{

    public Texture normal;
    public Texture hover;
    public Texture down;

    public Rect position;
    public PositionAnchor xAnchor = PositionAnchor.Middle;
    public PositionAnchor yAnchor = PositionAnchor.Middle;

    public event Action OnDown;
    public event Action OnUp;
    public event Action OnHover;
    public event Action OnLeave;
    public event Action OnStartDraw;
    public event Action OnEndDraw;
    public event Action OnUpdate;

    [HideInInspector] public bool isHover = false;
    [HideInInspector] public bool isDown = false;

    public virtual void Update(){

  if (isHover){
   if (Input.GetMouseButtonDown(0)){
    if (OnDown != null) OnDown();
    isDown = true;
   }
   if (Input.GetMouseButtonUp(0)){
    if (OnUp != null) OnUp();
    isDown = false;
   }
  }

  if (OnUpdate != null) OnUpdate();
    }

    public virtual void Draw(float ratio, Vector2 offset){

  if (OnStartDraw != null) OnStartDraw();

  float x = 0f;
  if (xAnchor == PositionAnchor.Left) x = position.x * ratio;
  if (xAnchor == PositionAnchor.Middle) x = position.x * ratio +offset.x;
  if (xAnchor == PositionAnchor.Right) x = Screen.width - (position.x + position.width) * ratio;

  float y = 0f;
  if (yAnchor == PositionAnchor.Left) y = position.y * ratio;
  if (yAnchor == PositionAnchor.Middle) y = position.y * ratio +offset.y;
  if (yAnchor == PositionAnchor.Right) y = Screen.height - (position.y + position.height) * ratio;

  float width = position.width * ratio;
  float height = position.height * ratio;

  float mousex = CustomCursor.GetX();
  float mousey = CustomCursor.GetY();

  if (mousex >= x && mousex <= x+width && mousey >= y && mousey <= y + height){
   if (!isHover && OnHover != null) OnHover();
   isHover = true;
  } else {
   if (isHover && OnLeave != null) OnLeave();
   isHover = false;
  }

  Texture texture;
  if (isHover && isDown){
   texture = down;
  } else if (isHover){
   texture = hover;
  } else {
   texture = normal;
  }

  GUI.DrawTextureWithTexCoords(new Rect(x, y, width, height), texture, new Rect(0, 0, 1, 1));

  if (OnEndDraw != null) OnEndDraw();

    }

}

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class AutoMatch : MonoBehaviour {

    public CanvasScaler scaler;
    private Vector2 lastScreenSize = Vector2.zero;

    void Update(){
        UpdateMatchRatio();
    }

    private void UpdateMatchRatio(){

        if (lastScreenSize.x != (float)Screen.width || lastScreenSize.y != (float)Screen.height){
            lastScreenSize = new Vector2((float)Screen.width, (float)Screen.height);

            float widthRatio = Screen.width/scaler.referenceResolution.x;
            float heightRatio = Screen.height/scaler.referenceResolution.y;

            if (widthRatio > heightRatio)
                scaler.matchWidthOrHeight = 1f;
            else
                scaler.matchWidthOrHeight = 0f;
        }    
    }  
}