带有MotionLayout的安卓折叠工具栏-当RecyclerView为空/不可滚动时禁用运动

<androidx.constraintlayout.motion.widget.MotionLayout
    android:id="@+id/motionLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintTop_toBottomOf="@id/toolbar" />

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

MotionLayout motionLayout = findViewById(R.id.motionLayout);
motionLayout.setTransitionListener(new MotionLayout.TransitionListener() {
    @Override
    public void onTransitionStarted(MotionLayout motionLayout, int startId, int endId) {
        // 过渡开始时的回调
    }

    @Override
    public void onTransitionChange(MotionLayout motionLayout, int startId, int endId, float progress) {
        // 过渡过程中的回调
    }

    @Override
    public void onTransitionCompleted(MotionLayout motionLayout, int currentId) {
        if (currentId == R.id.collapsed_state) {
            // 当过渡到折叠状态时禁用运动
            motionLayout.disableTransition(R.id.transition);
        }
    }

    @Override
    public void onTransitionTrigger(MotionLayout motionLayout, int triggerId, boolean positive, float progress) {
        // 过渡触发时的回调
    }
});