Is it possible to recolor a lottie animation programmatically?

Question

If I have a lottie animation in the form of a json file, is there a way to recolor it in code or even within the json itself?

(To be clear, I hope there's a way to do it without involving After Effects. For instance if I decide to change my app's primary color, the whole app will change except the animation unless there's a way to do that.)

Answer 1

I figured it out. For this example, let's say I want to recolor a specific layer to Color.RED.

You'll need your LottieAnimationView, a KeyPath, and a LottieValueCallback

private LottieAnimationView lottieAnimationVIew;
private KeyPath mKeyPath;
private LottieValueCallback<Integer> mCallback;

Then in your onCreate (or onViewCreated for a fragment) you'll get the animation with findViewById, as well as "addLottieOnCompositionLoadedListener" to the lottieAnimationView, in which you will setup the "mKeyPath" and "mCallback":

lottieAnimationVIew = findViewById(R.id.animationView);

lottieAnimationView.addLottieOnCompositionLoadedListener(new LottieOnCompositionLoadedListener() {
  @Override
  public void onCompositionLoaded(LottieComposition composition) {
    mKeyPath = getKeyPath(); // This is your own method for getting the KeyPath you desire. More on that below.
    mCallback = new LottieValueCallback<>();
    mCallback.setValue(Color.RED);
    checkBox.addValueCallback(mKeyPath, LottieProperty.COLOR, mCallback);
  }
});

The argument "LottieProperty.COLOR" specifies which property I am changing.

There's probably a better way to do this, but here's my "getKeyPath" method for finding the specific thing I want to change. It will log every KeyPath so you can see which one you want. Then it returns it once you've supplied the correct index. I saw that the one I want is the 5th in the list, hence the hard-coded index of 4.

private KeyPath getKeyPath() {
  List<KeyPath> keyPaths = lottieAnimationView.resolveKeyPath(new KeyPath("Fill", "Ellipse 1", "Fill 1"));
        
  for (int i = 0; i < keyPaths.size(); i++) {
    Log.i("KeyPath", keyPaths.get(i).toString());
  }
        
  if (keyPaths.size() == 5) {
    return keyPaths.get(4);
  }
  else {
    return null;
  }
}

Note that the "Fill", "Ellipse 1", "Fill 1" are strings I supplied to narrow the list down to just the ones that have those keys, because I know that the layer I want will be among those. There's likely a better way to do this as well.