Help! AnimationClip.SetCurve can't set curve for child object

Getting Started
1

I use the sample code from the document from:

The quad is static, if I bind the animation to child object “Lower”, it is animated.

I spent several days for it, hope someone can help me.

2

What is the problem, does the Sample code not work ?

3

Yes, the sample code doesn’t work.

The code:

// Create the clip with the curve
AnimationClip clip = new AnimationClip();
clip.SetCurve(“Lower”, typeof(Transform), “m_LocalPosition.z”, curve);
clip.legacy = true;

And clip SetCurve didn’t set the animation to “Lower”.

If I bind the animation directly to “Lower” object, it is ok.