Bug with alpha?

Hi guys.
I need to make a fade-out effect for my label.
Here is my code:

Code (CSharp):

1.  
2. using UnityEngine;
3. using UnityEngine.UI;
4.  
5. public class TweenAlpha : MonoBehaviour
6. {
7.     public float Speed;
8.     private Text Label;
9.     private float alpha;
10.     private Color color;
11.  
12.     /* -------- */
13.  
14.     void Start()
15.     {
16.         Label = GetComponent<Text>();
17.         if(Label == null)
18.             this.enabled = false;
19.         color = Label.color;
20.     }
21.  
22.     /* -------- */
23.  
24.     void Update()
25.     {
26.         alpha += Time.deltaTime / Speed;
27.         color.a = alpha;
28.  
29.         Label.color = color;
30.     }
31.  
32.     /* -------- */
33. }
34.  

For example:
Speed = 3 (Fade-in effect)
Speed = -3 (Fade-out effect).

As i said i need to make a fade-out effect,but here is my problem : the alpha value of my label becomes immediately...let's say 'zero'.
However, fade-in effect works fine with this script.

 

That's because you haven't assigned alpha a value so it will always be initialised to zero.

Rather than using a local variable you could just do:

Code (CSharp):

1. void Update()
2. {
3.     color.a = color.a + Time.deltaTime / Speed;
4.     Label.color = color;
5. }
6.  

There's potentially a few other issues in that code though, like there's no end to the fade etc...

 

Thanks! It works now.

Well,this is just a test