@Nullable
  private Typeface getTypeface(Font font) {
    if (typefaceCallbackAnimation != null) {
      Typeface callbackTypeface = typefaceCallbackAnimation.getValue();
      if (callbackTypeface != null) {
        return callbackTypeface;
      }
    }
    Typeface drawableTypeface = lottieDrawable.getTypeface(font);
    if (drawableTypeface != null) {
      return drawableTypeface;
    }
    return font.getTypeface();
  }
Configures the [fillPaint] and [strokePaint] used for drawing based on currently active text ranges.

@param parentAlpha A value from 0 to 255 indicating the alpha of the parented layer.
lottie/src/main/java/com/airbnb/lottie/model/layer/TextLayer.java