Add COLOR to solid layer

lottie/src/main/java/com/airbnb/lottie/LottieAnimationView.java

@@ -1021,6 +1021,13 @@ public List<KeyPath> resolveKeyPath(KeyPath keyPath) {
     return lottieDrawable.resolveKeyPath(keyPath);
   }
 
+  /**
+   * Clear the value callback for all nodes that match the given {@link KeyPath} and property.
+   */
+  public <T> void clearValueCallback(KeyPath keyPath, T property) {
+    lottieDrawable.addValueCallback(keyPath, property, (LottieValueCallback<T>) null);
+  }
+
   /**
    * Add a property callback for the specified {@link KeyPath}. This {@link KeyPath} can resolve
    * to multiple contents. In that case, the callback's value will apply to all of them.

lottie/src/main/java/com/airbnb/lottie/LottieDrawable.java

@@ -1282,6 +1282,8 @@ public List<KeyPath> resolveKeyPath(KeyPath keyPath) {
    * <p>
    * Internally, this will check if the {@link KeyPath} has already been resolved with
    * {@link #resolveKeyPath(KeyPath)} and will resolve it if it hasn't.
+   *
+   * Set the callback to null to clear it.
    */
   public <T> void addValueCallback(
       final KeyPath keyPath, final T property, @Nullable final LottieValueCallback<T> callback) {

lottie/src/main/java/com/airbnb/lottie/model/layer/SolidLayer.java

@@ -24,6 +24,7 @@ public class SolidLayer extends BaseLayer {
   private final Path path = new Path();
   private final Layer layerModel;
   @Nullable private BaseKeyframeAnimation<ColorFilter, ColorFilter> colorFilterAnimation;
+  @Nullable private BaseKeyframeAnimation<Integer, Integer> colorAnimation;
 
   SolidLayer(LottieDrawable lottieDrawable, Layer layerModel) {
     super(lottieDrawable, layerModel);
@@ -43,6 +44,9 @@ public class SolidLayer extends BaseLayer {
     int opacity = transform.getOpacity() == null ? 100 : transform.getOpacity().getValue();
     int alpha = (int) (parentAlpha / 255f * (backgroundAlpha / 255f * opacity / 100f) * 255);
     paint.setAlpha(alpha);
+    if (colorAnimation != null) {
+      paint.setColor(colorAnimation.getValue());
+    }
     if (colorFilterAnimation != null) {
       paint.setColorFilter(colorFilterAnimation.getValue());
     }
@@ -88,6 +92,13 @@ public <T> void addValueCallback(T property, @Nullable LottieValueCallback<T> ca
         colorFilterAnimation =
             new ValueCallbackKeyframeAnimation<>((LottieValueCallback<ColorFilter>) callback);
       }
+    } else if (property == LottieProperty.COLOR) {
+      if (callback == null) {
+        colorAnimation = null;
+        paint.setColor(layerModel.getSolidColor());
+      } else {
+        colorAnimation = new ValueCallbackKeyframeAnimation<>((LottieValueCallback<Integer>) callback);
+      }
     }
   }
 }

snapshot-tests/src/androidTest/java/com/airbnb/lottie/snapshots/tests/DynamicPropertiesTestCase.kt

@@ -377,6 +377,14 @@ class DynamicPropertiesTestCase : SnapshotTestCase {
             assetName = "Tests/AnimatedShadow.json"
         )
 
+        testDynamicProperty(
+            "Solid Color",
+            KeyPath("Cyan Solid 1", "**"),
+            LottieProperty.COLOR,
+            LottieValueCallback(Color.YELLOW),
+            assetName = "Tests/SolidLayerTransform.json"
+        )
+
         withDrawable("Tests/DynamicGradient.json", "Gradient Colors", "Linear Gradient Fill") { drawable ->
             val value = object : LottieValueCallback<Array<Int>>() {
                 override fun getValue(frameInfo: LottieFrameInfo<Array<Int>>?): Array<Int> {
@@ -483,4 +491,4 @@ class DynamicPropertiesTestCase : SnapshotTestCase {
             drawable.progress = progress
         }
     }
-}
+}