我想测量ListView的高度(getHight()= 0)

ListView listView = findViewById(R.id.list_view);

ViewTreeObserver viewTreeObserver = listView.getViewTreeObserver();
viewTreeObserver.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        // 获取 ListView 的高度的参考：在 onGlobalLayout() 回调中，
        // ListView 的高度为 ListView 的 ViewTreeObserver 而不是 ListView 本身
        int height = listView.getHeight();
        // 取消 ViewTreeObserver 的回调，以便在需要时进行其他测量
        viewTreeObserver.removeOnGlobalLayoutListener(this);
    }
});

OnScrollListener scrollListener = new OnScrollListener() {
    @Override
    public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
        // 当 RecyclerView 滚动状态改变时调用
        if (newState == RecyclerView.SCROLL_STATE_DRAGGING) {
            // 当 ListView 项被拖动时调用
            int firstVisible = recyclerView.findFirstVisibleItemPosition();
            int lastVisible = recyclerView.findLastVisibleItemPosition();
            int totalItemCount = recyclerView.getAdapter().getItemCount();
            int height = recyclerView.getHeight();

            // 计算 ListView 的高度
            int listViewHeight = (firstVisible == 0 ? 0 : (lastVisible == totalItemCount - 1 ? height : (firstVisible + lastVisible) * height / 2));
            // 设置 ListView 的高度
            recyclerView.setLayoutParams(new LinearLayoutManager.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, listViewHeight));
        }
    }

    @Override
    public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
        // 当 RecyclerView 滚动时调用
    }
};

recyclerView.addOnScrollListener(scrollListener);