Animation does not play when startAnimation is called in onBindViewHolder of an existing view

Describe the bug When calling startAnimation in a RecyclerView’s onBindViewHolder, the animation does not play. This issue was partially fixed in https://github.com/airbnb/lottie-android/issues/1324, but that fix only handles the case when the LottieAnimationView is first created, and not when it is rebound with different data.

The cause of the issue appears to be that when onBindViewHolder is called, the view is in an unusual state where it is attached to the window, but isShown is false because it has no parent.

Steps To Reproduce Here is a unit test that demonstrates the issue:

diff --git a/LottieSample/src/androidTest/java/com/airbnb/lottie/samples/FragmentVisibilityTests.kt b/LottieSample/src/androidTest/java/com/airbnb/lottie/samples/FragmentVisibilityTests.kt
index fc338b93..c48c684d 100644
--- a/LottieSample/src/androidTest/java/com/airbnb/lottie/samples/FragmentVisibilityTests.kt
+++ b/LottieSample/src/androidTest/java/com/airbnb/lottie/samples/FragmentVisibilityTests.kt
@@ -195,6 +195,51 @@ class FragmentVisibilityTests {
         onView(withId(R.id.animation_view)).check(matches(isAnimating()))
     }
 
+    @Test
+    fun testRecyclerViewCanAutoPlayInOnBindRebind() {
+        class TestFragment : Fragment() {
+            override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+                return RecyclerView(requireContext()).apply {
+                    layoutManager = LinearLayoutManager(requireContext(), LinearLayoutManager.VERTICAL, false)
+                    // Setting itemAnimator to null is important for this test in order to
+                    // prevent the recyclerview from creating an additional viewholder for the
+                    // purposes of animation.
+                    itemAnimator = null
+                    adapter = object : RecyclerView.Adapter<RecyclerView.ViewHolder>() {
+                        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+                            return object : RecyclerView.ViewHolder(LottieAnimationView(parent.context).apply {
+                                id = R.id.animation_view
+                                setAnimation(R.raw.heart)
+                                IdlingRegistry.getInstance().register(LottieIdlingResource(this))
+                            }) {}
+                        }
+
+                        override fun getItemCount(): Int = 1
+
+                        override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+                            (holder.itemView as LottieAnimationView).apply {
+                                // Cancel first, then play. This prevents the animation from
+                                // carrying over from the initial binding.
+                                cancelAnimation()
+                                playAnimation()
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        val fragmentScenario = launchFragmentInContainer<TestFragment>()
+        // I wasn't able to figure out exactly what was needed to create an idling resource.
+        // Waiting for [RecyclerView.doOnLayout] was insufficient.
+        Thread.sleep(500)
+        fragmentScenario.onFragment { fragment ->
+            (fragment.view as RecyclerView).adapter!!.notifyItemChanged(0)
+        }
+        Thread.sleep(500)
+        onView(withId(R.id.animation_view)).check(matches(isAnimating()))
+    }
+
     @Test
     fun testDoesntAutoplay() {
         class TestFragment : Fragment() {

[oissaq]

I’m having the same issue described here and in #1284 My workaround for now is to use post { icon.playAnimation() } That seems to work but wondering if there’s a better solution.

[gpeal]

I re-checked the test in the description (thank you for that) after landing https://github.com/airbnb/lottie-android/pull/1981 and the test now passes!