How to listen for UI Resize Events

Questions & Answers
1

I hear that the new 4.6 UI’s layout is event driven.

I am having great difficulty finding the event to listen to / handler to interface for listening when a RectTransform changes.

3

For future reference, there is a function that seems to work pretty well for this:

UI.Graphic.OnRectTransformDimensionsChange

I’ve used it to do responsive stacking columns and other neat tricks.

2

Hi there is a tranform.hasChanged, but this seems to get called constantly…

But this script seems to work, btw. used localToWorldMatrix so that it would detect movement if attached as a child of another object that says rotates, …

using UnityEngine;
using System.Collections;

public class TransFormChange : MonoBehaviour {

	private Matrix4x4 old;
	// Use this for initialization
	void Start () {
		old = transform.localToWorldMatrix;
	}
	
	// Update is called once per frame
	void Update () {
		//if (transform.hasChanged)
		if (!old.Equals(transform.localToWorldMatrix)) 
		{
			Debug.Log (transform.position);
			old = transform.localToWorldMatrix;
		}
	}
}
4

you have to set it to false again.

         void Update () {
             if (transform.hasChanged)
             {
                 Debug.Log (transform.position);
                 transform.hasChanged = false;
             }
         }