Flutter 如果有空间则居中CustomScrollView

与ListView类似，CustomScrollView具有包络处理变量，当设置为TRUE时，将try 最小化滚动区域的高度.

Scaffold的默认对齐方式是左上角，因此一旦收缩卷动视图，您将需要添加中心小部件作为它的父部件，以获得所需的中心对齐方式.代码如下所示:

return Scaffold(
      body: Center(
        child: CustomScrollView(
          shrinkWrap: true,
          physics: AlwaysScrollableScrollPhysics(
            parent: BouncingScrollPhysics(),
          ),
          controller: controller,
          slivers: [
            SliverToBoxAdapter(
              child: Center(
                child: Padding(
                  padding: EdgeInsets.symmetric(vertical: 64),
                  child: Text(
                    'Title',
                    style: theme.textTheme.titleLarge?.copyWith(
                      fontWeight: FontWeight.bold,
                      color: theme.colorScheme.onPrimary,
                    ),
                  ),
                ),
              ),
            ),
            SliverList.builder(
              itemCount: tiles.length,
              itemBuilder: (context, index) {
                final text = tiles[index];
                return Card(
                  margin: const EdgeInsets.symmetric(
                    horizontal: 24,
                    vertical: 8,
                  ),
                  child: ListTile(
                    title: Text(
                      text,
                      style: theme.textTheme.bodyLarge,
                    ),
                  ),
                );
              },
            ),
          ],
        ),
      ),
    );