MotionLayout with vertical ScrollView

Question

I'm trying to make animation with motion layout, and want to set scrollView as targetAnchor for motion scene onSwipe Transition, but it doesn't work. Maybe I don't know some thing about onSwipe transition.

Here is my layout file

    <androidx.constraintlayout.motion.widget.MotionLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/main_background_color"
        app:layoutDescription="@xml/base_scroll_scene">

        <ImageView
            android:id="@+id/background_image"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_marginBottom="@dimen/scrollable_background_image_margin_bottom"
            android:scaleType="centerCrop"
            android:src="@drawable/lift_bg"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="@dimen/top_gradient_mask_height"
            android:background="@drawable/top_gradient_mask"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <ImageView
            android:id="@+id/ski_more_logo"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="@dimen/ski_more_logo_margin_top"
            android:src="@drawable/ic_skimore_logo"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

        <ImageView
            android:id="@+id/locked_icon"
            android:layout_width="32dp"
            android:layout_height="32dp"
            android:layout_marginTop="@dimen/locked_icon_margin_top"
            android:src="@drawable/ic_lock"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/ski_more_logo" />

        <FrameLayout
            android:id="@+id/bottom_gradient_mask"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:background="@drawable/bottom_gradient_mask"
            app:layout_constraintBottom_toBottomOf="@+id/background_image" />

        <ScrollView
            android:id="@+id/content_scroll_view"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:overScrollMode="never"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintTop_toTopOf="parent">


            <FrameLayout
                android:id="@+id/content_container_view"
                android:layout_width="match_parent"
                android:clickable="false"
                android:layout_height="match_parent" />


        </ScrollView>
    </androidx.constraintlayout.motion.widget.MotionLayout>

In scroll view programmatically i'm adding some content with big height, which will be scrollable.

And here is my motion scene

<MotionScene xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:motion="http://schemas.android.com/apk/res-auto">
    <Transition
        motion:constraintSetEnd="@+id/end"
        motion:constraintSetStart="@+id/start"
        motion:duration="1000">
        <OnSwipe
            motion:dragDirection="dragUp"
            motion:touchAnchorId="@+id/content_scroll_view"
            motion:touchAnchorSide="top" />
    </Transition>

    <ConstraintSet android:id="@+id/start"/>
    <ConstraintSet android:id="@+id/end">
        <Constraint
            android:id="@+id/background_image"
            android:layout_width="0dp"
            android:layout_height="@dimen/top_gradient_mask_height"
            android:layout_marginBottom="@dimen/scrollable_background_image_margin_bottom"
            android:scaleType="centerCrop"
            android:src="@drawable/lift_bg"
            motion:layout_constraintEnd_toEndOf="parent"
            motion:layout_constraintStart_toStartOf="parent"
            motion:layout_constraintTop_toTopOf="parent" />

    </ConstraintSet>

</MotionScene>

Please help me, Thanks.

Answer 1

Have you tried to replace ScrollView with NestedScrollView?

And, also, I would define ConstraintSet "start" as well.

Answer 2

I had the same issue on using a scrolling view with motion layout to implement my custom animations. But simply changing ScrollView to NestedScrollView fixed everything and animations work as expected