👀 Views: 45 💬 Answers: 1 📅 Created: 2025-06-08

android fragment motionlayout viewpager2 layout kotlin

I'm having a hard time understanding I've looked through the documentation and I'm still confused about I'm stuck on something that should probably be simple. I am working with a layout scenario when transitioning between fragments using MotionLayout within a ViewPager2 in my Android 14 application. The fragments contain MotionLayout animations designed to provide a smooth user experience. However, upon swiping between fragments, the layout occasionally does not render correctly, causing overlapping views and unexpected behavior. I have set up my ViewPager2 with a FragmentStateAdapter and implemented MotionLayout in each fragment. Here’s a simplified version of my implementation: ```kotlin class MyFragmentAdapter(fragmentActivity: FragmentActivity) : FragmentStateAdapter(fragmentActivity) { override fun getItemCount(): Int = 3 override fun createFragment(position: Int): Fragment { return when (position) { 0 -> FirstFragment() 1 -> SecondFragment() 2 -> ThirdFragment() else -> FirstFragment() } } } ``` In each fragment, I have defined my MotionLayout like this: ```xml <androidx.constraintlayout.motion.MotionLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/motionLayout" android:layout_width="match_parent" android:layout_height="match_parent" app:layoutDescription="@xml/scene"> <!-- Your views here --> </androidx.constraintlayout.motion.MotionLayout> ``` When I swipe between fragments, I sometimes get this behavior in the logcat: `java.lang.IllegalStateException: MotionLayout not started or already finished`. This seems to occur when the MotionLayout is trying to animate while the fragment is being replaced. I have tried calling `motionLayout.transitionToEnd()` in the `onPause()` method of my fragments, but it does not seem to resolve the scenario. I also ensured that I’m not triggering animations during fragment transitions. What could be causing this scenario? Are there any best practices for handling MotionLayout within ViewPager2 to avoid such layout problems? Any help would be appreciated! Any ideas what could be causing this? I'm working on a web app that needs to handle this. Any help would be greatly appreciated! Could this be a known issue?