Animating properties on an Animation Track?

Only serialized properties can be animated using the animation system, which is what the animation system.

The only other option is to create a custom clip that uses an animated playable behaviour parameter that writes to the property, like in the following example.

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.Playables;
5.  
6.  
7. [System.Serializable]
8. public class ScreenTextBehaviour : PlayableBehaviour
9. {
10.     public string text = "Sample Text";
11.     public Color vertexColor = Color.white; // This will be animated by timeline
12.    
13.     public override void ProcessFrame(Playable playable, FrameData info, object playerData)
14.     {
15.         var target = playerData as SomeTextType;
16.         if (target == null)
17.             return;
18.            
19.         target.color = vertexColor;
20.         target.text = text;      
21.     }
22. }
23.  
24. [System.Serializable]
25. public class ScreenTextClip : PlayableAsset
26. {
27.     public ScreenTextBehaviour template = new ScreenTextBehaviour();
28.  
29.     // Factory method that generates a playable based on this asset
30.     public override Playable CreatePlayable(PlayableGraph graph, GameObject go)
31.     {
32.         return ScriptPlayable<ScreenTextBehaviour>.Create(graph, template);
33.     }
34. }