Timeline playableasset lifecycle?

Unity Engine
1

Hi, scratching my head here trying to get a ‘lifecycle’ for created clips on a timeline.

I want to be able to bind my clip to an entry in an external database, which means i need to know when the clip is created and destroyed. This following code seems to work, but only if it’s being edited on a gameobject with a director. If I select the timeline as an asset in the Project view, the createplayable event doesn’t seem to fire.

public class TriggerDialog : PlayableAsset {
    private int instanceID = -1;

    public override Playable CreatePlayable (PlayableGraph graph, GameObject owner) {
        if (instanceID != GetInstanceID()) {
            // the playable is created whenever the graph comes into memory, in edit mode as well
            instanceID = GetInstanceID ();
            Debug.Log ("being born.. my new id is "+ instanceID);
            // create in the database here
        }

        // creating the specific behavior that actually runs on the timeline
        TriggerDialogBehaviour b = new TriggerDialogBehaviour();
        ScriptPlayable<TriggerDialogBehaviour> p = ScriptPlayable<TriggerDialogBehaviour>.Create(graph, b);
        return p;
    }
      
    public void OnDestroy () {
        Debug.Log ("Im dying, and my ID was " + id);
        // remove from the database here
    }
}

How can I know when a custom clip type is created and destroyed? Most of the methods/events seem to handle the creation and execution of the graph in playmode, rather than editor scripting.

2

PlayableAssets are ScriptableObjects, so the same lifetime rules apply. OnEnable and OnDisable should do the trick (or Awake/Destroy).

CreatePlayable is only called when an instance of the timeline is needed to play. So when clicking on an asset in the project view, there is no instance created because there is no playable director associated with it. You can still view the timeline, but it is out of context.

3

Awake() and OnDestroy() worked great, thanks!

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