How to Tween alpha of an image?

On NGUI it was done with TweenAlpha.Begin().
How to fade in an image in new (awesome btw.) UI?

 

maybe Graphics.CrossFadeAlpha?

 

Bumping this. What if you have a group of objects? I'm using CanvasGroup to change the alpha of a message box & its contents, and this does not seem to be an option.

(my bad, I was referencing the wrong object. this works.)

 

Would also be interested in a clean solution.
Currently i am getting every CanvasRenderer at the start. Then i am changing their alpha by looping trough them.

Code (csharp):

1. cr=GetComponentsInChildren<CanvasRenderer>();
2. for(int i=0;i<cr.Length;i++)
3. cr[i].SetAlpha(alphaValue);

There should be an easier way to fadein/out a group of nested gameobjects.

 

I'm not sure what "this" refers to, since CanvasGroup does precisely what you describe.

@Kogar use a CanvasGroup, that's exactly what they do.

 

@StarManta Exactly what i needed. I had not tried CanvasGroup yet.
Would be nice to have a fading included, but an IEnumerator does it too. I based mine on //http://answers.unity3d.com/questions/286453/quick-change-over-time-math.html

Code (csharp):

1. public float alphaFadeSeconds = 0.1f;
2. private CanvasGroup cg; //get the component in start()
3.  
4. IEnumerator alphaFade(float alpha)
5. {
6.    float start = Time.time;
7.    while(cg.alpha != alpha)
8.    {
9.      float elapsed = Time.time - start;
10.      float normalisedTime = Mathf.Clamp((elapsed / alphaFadeSeconds)*Time.deltaTime, 0, 1);
11.      cg.alpha = Mathf.Lerp(cg.alpha, alpha, normalisedTime) ;
12.      yield return 0;  
13.    }
14.    yield return true;
15. }
16.  
17. void setVisibility(float alpha = 0)
18. {
19.    StopCoroutine("alphaFade");  //stop currently fading coroutine
20.    StartCoroutine("alphaFade", alpha); //start from current alpha state to target alpha
21. }

 

in a few weeks i should have a nice tweening soultion in for the new UI system, that allows for straight up tweening or via curves, for some effects.

 

Use CanvasGroup and fade that alpha. That has the benefit of fading every game object under it. You can animate this property through script or through Animation/Animator in any way you see fit with curves and all.

 

Just stumbled on this issue as well. You could modifiy the default iTween script like this to make it work (though it should certainly be optimized...).

Code (CSharp):

1.  
2. // Somewhere at line 3345 in method GenerateColorToTargets()
3. else if(GetComponent<CanvasRenderer>())
4. {
5.     colors = new Color[1,3];
6.     colors[0,0] = colors[0,1] = GetComponent<CanvasRenderer>().GetColor();
7. }
8.  

Code (CSharp):

1.  
2. // Somewhere at line 4128 in method ApplyColorToTargets()
3. else if(GetComponent<CanvasRenderer>())
4. {
5.     GetComponent<CanvasRenderer>().SetColor(colors[0,2]);
6. }
7.  

Code (CSharp):

1.  
2. // Somewhere at line 4150 in method ApplyColorToTargets()
3. else if(GetComponent<CanvasRenderer>())
4. {
5.     GetComponent<CanvasRenderer>().SetColor(colors[0,1]);
6. }
7.  

Example call to fade out a child image of the Canvas GameObject:
iTween.ColorTo(GameObject.Find("Canvas").transform.Find("Image").gameObject, new Color(0.0F,0.0F,0,0F), 1.0F);

 

Awesome. It work. thank you