dart - Flutter NestedScrollView/SliverAppBar - 不需要的底边距

Question

使用 Navigation Drawer 构建应用栏:

@override
  Widget build(BuildContext context) {
    var drawerOptions = <Widget>[];
    for (var i = 0; i < widget.drawerItems.length; i++) {
      var d = widget.drawerItems[i];
      drawerOptions.add(new ListTile(
        leading: new Icon(d.icon),
        title: new Text(d.title),
        selected: i == _selectedDrawerIndex,
        onTap: () => _onSelectItem(i),
      ));
    }
    drawerOptions.add(
        new RaisedButton(onPressed: () => {}, child: new Text("Ustawienia")));

    return new Scaffold(
        body: NestedScrollView(
          headerSliverBuilder: (BuildContext context, bool innerBoxIsScrolled) {
            return <Widget>[
              SliverAppBar(
                expandedHeight: 130.0,
                floating: false,
                pinned: true,
                flexibleSpace: FlexibleSpaceBar(
                  title:
                      new Text(widget.drawerItems[_selectedDrawerIndex].title),
                ),
              ),
            ];
          },
          body: _getDrawerItemWidget(_selectedDrawerIndex),
        ),
        drawer: new Drawer(
          child: new Column(
            children: <Widget>[
              new UserAccountsDrawerHeader(
                  accountName: new Text("Gość"), accountEmail: null),
              new Column(children: drawerOptions)
            ],
          ),
        ));

结果:

所以正上方有多余的白边。如果我尝试使用常规的 appbar，这样:

return new Scaffold(
      appBar: new AppBar(
        // here we display the title corresponding to the fragment
        // you can instead choose to have a static title
        title: new Text(widget.drawerItems[_selectedDrawerIndex].title),
      ),
      drawer: new Drawer(
        child: new Column(
          children: <Widget>[
            new UserAccountsDrawerHeader(
                accountName: new Text("Gość"), accountEmail: null),
            new Column(children: drawerOptions)
          ],
        ),
      ),
      body: _getDrawerItemWidget(_selectedDrawerIndex),
    );

结果很好，没有任何额外的余量:

如何在展开模式下移除不需要的额外边距并将标题左对齐(它应该放在汉堡菜单指示器下方)。

DrawerItem 类定义:

class DrawerItem {
  String title;
  IconData icon;

  DrawerItem(this.title, this.icon);
}

drawerItems 定义如下:

final drawerItems = [
    new DrawerItem("Option1", Icons.list),
    new DrawerItem("Option2", Icons.event_note),
    new DrawerItem("Option3", Icons.account_balance),
   //... etc
  ];

Answer 1

我在嵌套 ScrollView 中遇到了同样的问题。我使用 GridView 作为正文并将其填充设置为 0 以消除空格

GridView.builder(
   padding: EdgeInsets.only(top: 0),

因此，无论您从该方法 _getDrawerItemWidget(_selectedDrawerIndex) 返回什么小部件，请尝试向其添加填充。