Android中如何实现滚动时将LinearLayout平滑滑出Activity？

你碰到的问题本质是：当把LinearLayout设为GONE后，RelativeLayout会立刻触发重布局，让RecyclerView直接顶到顶部，这就造成了突兀的跳变，而非平滑过渡。下面给你几个实用的解决方案，按需选择：

方案一：同步动画布局高度与RecyclerView边距（基于原RelativeLayout） #

不用设置GONE，而是通过属性动画同时修改LinearLayout的高度和RecyclerView的topMargin，让两者的变化完全同步，视觉上就会非常平滑：

RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {
    private int scrollDistance = 0;
    private boolean isVisible = true;
    private static final float MINIMUM = 50;
    private int originalLinearHeight;
    private int originalRecyclerTopMargin;

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        
        // 初始化原始高度和边距（只执行一次）
        if (originalLinearHeight == 0) {
            originalLinearHeight = linearLayout.getHeight();
            RelativeLayout.LayoutParams recyclerParams = (RelativeLayout.LayoutParams) recyclerView.getLayoutParams();
            originalRecyclerTopMargin = recyclerParams.topMargin;
        }

        if (isVisible && scrollDistance > MINIMUM) {
            // 隐藏：LinearLayout高度缩为0，RecyclerView同步上移
            ValueAnimator animator = ValueAnimator.ofInt(originalLinearHeight, 0);
            animator.setDuration(300);
            animator.addUpdateListener(animation -> {
                int currentHeight = (int) animation.getAnimatedValue();
                // 更新LinearLayout高度
                LinearLayout.LayoutParams linearParams = (LinearLayout.LayoutParams) linearLayout.getLayoutParams();
                linearParams.height = currentHeight;
                linearLayout.setLayoutParams(linearParams);
                // 更新RecyclerView的topMargin，让它跟着上移
                RelativeLayout.LayoutParams recyclerParams = (RelativeLayout.LayoutParams) recyclerView.getLayoutParams();
                recyclerParams.topMargin = originalRecyclerTopMargin + (originalLinearHeight - currentHeight);
                recyclerView.setLayoutParams(recyclerParams);
            });
            animator.start();
            scrollDistance = 0;
            isVisible = false;
        } else if (!isVisible && scrollDistance < -MINIMUM) {
            // 显示：恢复LinearLayout高度，RecyclerView同步下移
            ValueAnimator animator = ValueAnimator.ofInt(0, originalLinearHeight);
            animator.setDuration(300);
            animator.addUpdateListener(animation -> {
                int currentHeight = (int) animation.getAnimatedValue();
                LinearLayout.LayoutParams linearParams = (LinearLayout.LayoutParams) linearLayout.getLayoutParams();
                linearParams.height = currentHeight;
                linearLayout.setLayoutParams(linearParams);
                RelativeLayout.LayoutParams recyclerParams = (RelativeLayout.LayoutParams) recyclerView.getLayoutParams();
                recyclerParams.topMargin = originalRecyclerTopMargin + (originalLinearHeight - currentHeight);
                recyclerView.setLayoutParams(recyclerParams);
            });
            animator.start();
            scrollDistance = 0;
            isVisible = true;
        }

        // 累计滚动距离，判断是否触发显示/隐藏
        if ((isVisible && dy > 0) || (!isVisible && dy < 0)) {
            scrollDistance += dy;
        }
    }
};
recyclerView.addOnScrollListener(onScrollListener);

方案二：改用ConstraintLayout（更推荐，布局更灵活） #

RelativeLayout的约束能力有限，换成ConstraintLayout可以更轻松实现这种联动动画。先修改你的XML布局：

<androidx.constraintlayout.widget.ConstraintLayout 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="wrap_content">

    <LinearLayout
        android:id="@+id/linear_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:layout_constraintTop_toTopOf="parent">
        <!-- 你的ImageView组件 -->
    </LinearLayout>

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

</androidx.constraintlayout.widget.ConstraintLayout>

然后在代码里利用ConstraintSet和TransitionManager实现平滑的约束切换：

RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {
    private int scrollDistance = 0;
    private boolean isVisible = true;
    private static final float MINIMUM = 50;
    private ConstraintLayout parentLayout;
    private ConstraintSet originalConstraints = new ConstraintSet();
    private ConstraintSet hiddenConstraints = new ConstraintSet();

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        
        // 初始化约束集合（只执行一次）
        if (parentLayout == null) {
            parentLayout = (ConstraintLayout) linearLayout.getParent();
            originalConstraints.clone(parentLayout);
            hiddenConstraints.clone(parentLayout);
            // 隐藏状态下，让RecyclerView的顶部直接约束到父布局顶部
            hiddenConstraints.connect(R.id.recycler_view, ConstraintSet.TOP, ConstraintSet.PARENT_ID, ConstraintSet.TOP);
        }

        if (isVisible && scrollDistance > MINIMUM) {
            // 先让LinearLayout滑出屏幕，再切换约束并隐藏
            linearLayout.animate()
                    .translationY(-linearLayout.getHeight() - 12)
                    .setDuration(300)
                    .withEndAction(() -> {
                        TransitionManager.beginDelayedTransition(parentLayout);
                        hiddenConstraints.applyTo(parentLayout);
                        linearLayout.setTranslationY(0); // 重置位移，避免下次显示出错
                        linearLayout.setVisibility(View.GONE);
                    });
            scrollDistance = 0;
            isVisible = false;
        } else if (!isVisible && scrollDistance < -MINIMUM) {
            // 先恢复约束，再让LinearLayout滑入屏幕
            linearLayout.setVisibility(View.VISIBLE);
            TransitionManager.beginDelayedTransition(parentLayout);
            originalConstraints.applyTo(parentLayout);
            linearLayout.animate().translationY(0).setDuration(300);
            scrollDistance = 0;
            isVisible = true;
        }

        // 累计滚动距离
        if ((isVisible && dy > 0) || (!isVisible && dy < 0)) {
            scrollDistance += dy;
        }
    }
};
recyclerView.addOnScrollListener(onScrollListener);

方案三：仅滑出不占位（最简单，适合不需要节省空间的场景） #

如果不需要RecyclerView占据LinearLayout的位置，只是让它滑出视野，那完全不用设置GONE，保持LinearLayout为VISIBLE，仅通过translationY让它移出屏幕即可。这样RecyclerView的位置不会变化，也就不会有跳变问题，代码简化为：

RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {
    private int scrollDistance = 0;
    private boolean isVisible = true;
    private static final float MINIMUM = 50;

    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        if (isVisible && scrollDistance > MINIMUM) {
            linearLayout.animate().translationY(-linearLayout.getHeight() - 12).setDuration(300);
            scrollDistance = 0;
            isVisible = false;
        } else if (!isVisible && scrollDistance < -MINIMUM) {
            linearLayout.animate().translationY(0).setDuration(300);
            scrollDistance = 0;
            isVisible = true;
        }

        if ((isVisible && dy > 0) || (!isVisible && dy < 0)) {
            scrollDistance += dy;
        }
    }
};
recyclerView.addOnScrollListener(onScrollListener);

根据你的实际需求选一个方案就行啦～

内容的提问来源于stack exchange，提问作者Always Learner