How to retrieve the value of a property?

[stevekirby]

I'm having no trouble using getKeyPath() and addValueCallback() but I cannot figure out how to simply retrieve the value of a property, eg as an array. How can I determine the Position property of a layer as an array of [x,y,z] values? Better still, where is the documentation that explains how to do this! I've been googling for over an hour for something that seemingly ought to be so simple.

[Inventsable]

Hi Steve. There is no documentation for Lottie-API unfortunately, only what's on the README and the samples:

// Importing lottie-web, lottie API and our JSON:
import * as lottie from "lottie-web"
require("lottie_api.js");
const ANIM_FILE = require("data.json")

// First we load our JSON into Lottie:
const ANIM_DATA = lottie.loadAnimation({
  animType: "svg",
  loop: true,
  prerender: true,
  autoplay: true,
  container: document.getElementById("container"),
  animationData: ANIM_DATA
});

// Then create the API object with our constructed data above:
const API = lottie_api.createAnimationApi(ANIM_DATA) // lottie_api is a global object

// We can retrieve the current X/Y via addValueCallback's second parameter
API.addValueCallback(
  // But we need to feed a reference via the first parameter before this, targeting Layer 1's Transform > Position propGroup:
  API.getKeyPath(`Layer 1,Transform,Position`),
  (currentValue) => {
    // The parameter value here is an Array value of the position. This is only the position at the point of the callback though, not realtime as the animation is playing.

    // If we want to set these to be reactive (but not for getting unfortunately, only setting):
    return [someDynamicX, someDynamicY]
  }
)

[Inventsable]

#13

[stevekirby]

Thanks Tom. Through digging into examples I have managed to figure out this which seems to be working:

        var posKeyPath = animationAPI.getKeyPath('Target Layer,Transform,Position');
        var posVal = posKeyPath.getPropertyAtIndex(0).getValue();

Though I have not tested it thoroughly yet.