ResponsiveCanvasHelper

using System.Collections;
using System.Collections.Generic;
using System.Security.Cryptography.X509Certificates;
using TastyTools;
using UnityEngine;
using UnityEngine.UI;

public class ResponsiveCanvasHelper : MonoBehaviour
{
    public static bool _DEBUG = false;
    public RectTransform mainContainer;
    Vector2 resolution;
    float sixteenByNine = 16f / 9f;
    CanvasScaler scaler;

    void OnEnable()
    {
        StartCoroutine(CheckResolution());
    }

    IEnumerator CheckResolution()
    {
        var checkDelay = new WaitForSecondsRealtime(1);
        while (true)
        {
            if (resolution.x != Screen.width || resolution.y != Screen.height)
            {
                UpdateResponsiveness();
            }
            yield return checkDelay;
        }
    }

    void UpdateResponsiveness()
    {
        if(_DEBUG) Debug.LogWarning("Detected window size change");
        resolution.x = Screen.width;
        resolution.y = Screen.height;
        if (scaler == null) scaler = GetComponent<CanvasScaler>();
        
        
        // check if 16:9 or wider
        var diff = (resolution.x / resolution.y) - sixteenByNine;
        if (Mathf.Abs(diff) < 0.001f || diff > 0 ) // wider
        {
            // assume 16:9 or wider
            if(_DEBUG) Debug.Log("We're wide!");
            scaler.matchWidthOrHeight = 1;
            mainContainer.sizeDelta = scaler.referenceResolution;
            mainContainer.anchorMax = Vector2.one * 0.5f; // detach
            mainContainer.anchorMin = mainContainer.anchorMax;
            
        }
        else
        {
            // assume tall
            if(_DEBUG) Debug.Log("We're tall!");
            scaler.matchWidthOrHeight = 0;
            mainContainer.sizeDelta = Vector2.zero;
            mainContainer.anchorMax = Vector2.one; // stretch
            mainContainer.anchorMin = Vector2.zero;
        }
        
    }

    [InspectorButton("DebugMe")] public bool _debug;

    public void DebugMe()
    {
        Debug.Log(mainContainer.anchorMax);
        Debug.Log(mainContainer.anchorMin);
    }
}