make buttons appear slowly

Questions & Answers
1

I want to make three buttons to appear slowly,can anybody tell me?

using UnityEngine;
using System.Collections;

public class Test3 : MonoBehaviour {

// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {
    }
Rect button=new Rect(100,100,100,100);
Rect from=new Rect(100,100,100,100);
bool isShow=true;
Rect to =new Rect(25,30,250,30);
void OnGUI(){

    GUI.BeginGroup(new Rect(20,20,300,300));
    ChangePosition();
    if(!isShow)
        ShowMenu();
    GUI.Box(new Rect(0,0,300,300),"  ");
    GUI.EndGroup();
}
void function(Rect r){
    button=r;
}
Color colorfrom=new Color(1,1,1,0);
Color colorto=new Color(1,1,1,1);
void ShowMenu(){
    GUI.BeginGroup(new Rect(50,70,250,200));
    GUILayout.BeginVertical(GUILayout.Width(250),GUILayout.Height(200));
    GUILayout.Button("button1",GUILayout.Width(200),GUILayout.Height(30));
    GUILayout.Button("button2",GUILayout.Width(200),GUILayout.Height(30));
    GUILayout.Button("button3",GUILayout.Width(200),GUILayout.Height(30));
    GUILayout.EndVertical();
    GUI.EndGroup();
}
void ChangePosition(){
    if(GUI.Button(button,"Menu")){
        if(isShow){
        iTween.ValueTo(gameObject.gameObject,iTween.Hash("from",button,"to",to,"easeType",iTween.EaseType.easeInOutBack,"onupdate","function"));

        }
    else
    {   
        iTween.ValueTo(this.gameObject,iTween.Hash("from",button,"to",from,"easeType",iTween.EaseType.easeInOutBack,"onupdate","function"));
    }
    isShow=!isShow;
}
}
void ChangeColor(Color c){
    colorfrom=c;
}

}

2

You could set the Alpha property to 0 initially, and then increase it at some rate in the update function until alpha reaches 1.