This is called when the wizard is opened or whenever the user changes something in the wizard.

This allows you to set the helpString, errorString and enable/disable the Create button via isValid. Also it lets you change labels (for timers i.e.) or buttons when the wizard is being shown

See Also: ScriptableWizard.DisplayWizard

Scriptable Wizard window for clonning a Game Object.

	// C#
	// Simple Wizard that clones an object several times.
	using UnityEngine;
	using UnityEditor;
	using System.Collections;
	
	public class CloneObjects : ScriptableWizard {
		
		public GameObject ObjectToCopy = null;
		public int numberOfCopies = 2;
		[MenuItem ("Example/Clone objects")]
		static void CreateWindow() {
			// Creates the wizard for display
			ScriptableWizard.DisplayWizard("Clone an object.", typeof(CloneObjects), "Clone!");
		}
		void OnWizardUpdate() {
			helpString = 
				"Clones an object a number of times and move the cloned objects to the origin";
			if(!ObjectToCopy) {
				errorString = "Please assign an object";
				isValid = false;
			} else {
				errorString = "";
				isValid = true;	
			}
		}
		void OnWizardCreate () {
			for(int i = 0; i < numberOfCopies; i++)
				Instantiate(ObjectToCopy, Vector3.zero, Quaternion.identity);
		}
	}