airbnb/lottie-android · error · IllegalStateException

Missing values for keyframe.

Error message

Missing values for keyframe.

What it means

Thrown by FloatKeyframeAnimation#getFloatValue when a keyframe's startValue or endValue is null. Float (e.g. opacity, rotation) interpolation needs two numeric endpoints; a null endpoint means the keyframe data is missing a value.

Source

Thrown at lottie/src/main/java/com/airbnb/lottie/animation/keyframe/FloatKeyframeAnimation.java:23

import java.util.List;

public class FloatKeyframeAnimation extends KeyframeAnimation<Float> {

  public FloatKeyframeAnimation(List<Keyframe<Float>> keyframes) {
    super(keyframes);
  }

  @Override Float getValue(Keyframe<Float> keyframe, float keyframeProgress) {
    return getFloatValue(keyframe, keyframeProgress);
  }

  /**
   * Optimization to avoid autoboxing.
   */
  float getFloatValue(Keyframe<Float> keyframe, float keyframeProgress) {
    if (keyframe.startValue == null || keyframe.endValue == null) {
      throw new IllegalStateException("Missing values for keyframe.");
    }

    if (valueCallback != null) {
      //noinspection ConstantConditions
      Float value = valueCallback.getValueInternal(keyframe.startFrame, keyframe.endFrame,
          keyframe.startValue, keyframe.endValue,
          keyframeProgress, getLinearCurrentKeyframeProgress(), getProgress());
      if (value != null) {
        return value;
      }
    }

    return MiscUtils.lerp(keyframe.getStartValueFloat(), keyframe.getEndValueFloat(), keyframeProgress);
  }

  /**
   * Optimization to avoid autoboxing.
   */

View on GitHub (pinned to 05ea92e903)

Solutions

  1. Inspect the JSON for the offending float keyframe and confirm both "s" and "e" numeric values are present.
  2. Re-export the animation from After Effects.
  3. Align the lottie-android version with the file's feature set.
  4. Simplify the animated property to eliminate the malformed keyframe.
Defensive patterns

Strategy: try-catch

Try / catch

lottieAnimationView.setFailureListener(t -> {
  if (t instanceof IllegalStateException && "Missing values for keyframe.".equals(t.getMessage())) {
    Log.w(TAG, "malformed float keyframe", t);
  } else throw new RuntimeException(t);
});

Prevention

When it happens

Trigger: Evaluating a float keyframe whose "s" or "e" value was not present or not parseable as a number; a keyframe object missing the end value field. The valueCallback branch is only entered after the null check, so a missing value throws before a callback could compensate.

Common situations: Truncated or hand-edited Lottie JSON; an export glitch producing a keyframe without an end value; schema mismatch between the file and the library.

Related errors

AI-assisted analysis of airbnb/lottie-android@05ea92e903 (2026-08-14). Data as JSON: /api/errors/582e7d52ca822a90. Report an issue: GitHub.