Tween color overlay of Spine animation - unity3d

Question

Im using Unity3D and character animations imported from Spine. I want to add a color overlay over those characters. For example, I have one character, I want to make it a "shadow" character, so I add the black color over it in this way:
GetComponent<SkeletonAnimation>().Skeleton.color = new Color(0f,0f,0f);
Nevertheless, I want a Tween between the regular color, and the new color. But, unfortunately, I can't do it with the DOColor method of DOTween. I try
GetComponent<SkeletonAnimation>().Skeleton.DOColor(Color.Black,1);
But the method DOColor for Skeleton doesn't exists. So which is the way to follow to accomplish this?

Answer 1

DoColor, DoMove, etc are shortcuts and extension method that written for unity's built-in components. SkeletonAnimation is not supported by DoTween extension methods. You can tween its color property like this:
Color yourColor = Color.white; //GetComponent<SkeletonAnimation>().Skeleton.color
Color targetColor = Color.black;
float duration = 1f;
DOTween.To(() => yourColor, co => { yourColor = co; }, targetColor, duration);
Also, You can write your own extension:
public static class MyExtensions{
public static Tweener DOColor(this SkeletonAnimation target,
Color endValue, float duration)
{
DOTween.To(() => target.color,
co => { target.color = co; },
endValue,
duration);
}
}

Answer 2

If you are working with UI, For SkeletonGraphic, following code works.
public static class Utilities
{
public static void DOColor(SkeletonGraphic skeletonGraphic, Color endValue, float duration)
{
DOTween.To(() => skeletonGraphic.color,
newColor => { skeletonGraphic.color = newColor; },
endValue,
duration);
}
}
And then you can call like:
private SkeletonGraphic _skeletonGraphic;
private void Start()
{
_skeletonGraphic = spineAnimationParent.GetComponentInChildren<SkeletonGraphic>();
}
Utilities.DOColor(_skeletonGraphic, Color.grey, 0.5f);
It is important to NOT pass the color by value (i.e. _skeletonGraphic.color as input of DOColor function would be bad), because since you want to change the color inside of your class, you need to pass reach reference in Utilities.DOColor().