flutter - 颤振：使用 RefreshIndicator 时没有刷新指示器

Question

我将 RefreshIndicator 添加到我的页面，但拉动刷新时没有可见的指示器。代码如下：

class HomePage extends StatefulWidget {
  HomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<HomePage> {

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: LocalGalleryTab(),
    );
  }
}

class LocalGalleryTab extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _LocalGalleryState();
  }
}

class _LocalGalleryState extends State<LocalGalleryTab> {
  @override
  Widget build(BuildContext context) {
    return new Container(child: new Center(
      child: new RefreshIndicator(
        child: Text("Local Gallery"),
        onRefresh: _refreshLocalGallery,
      ),
    ));
  }

  Future<Null> _refreshLocalGallery() async{
    print('refreshing stocks...');

  }
}

如何使用刷新指示器？颤振文档没有提供太多信息。

标签： flutterdartrefreshpull-to-refreshindicator

Answer 1

使用AlwaysScrollableScrollPhysics()将确保滚动视图始终是可滚动的，因此可以触发RefreshIndicator.

现在我认为创建滚动物理，BouncingScrollPhysics(parent: AlwaysScrollableScrollPhysics)而不仅仅是AlwaysScrollableScrollPhysics()滚动物理。因为 BouncingScrollPhysics 适用于反弹的短列表。现在需要包含 AlwaysScrollableScrollPhysics 才能获得预期的行为。

RefreshIndicator(
    onRefresh: _onRefresh,
    child: ListView(
      padding: EdgeInsets.all(8.0),
      physics: const BouncingScrollPhysics(parent: AlwaysScrollableScrollPhysics()),
      children: _listData.map((i) {
        return ListTile(
          title: Text("Item $i"),
        );
      }).toList(),
    )
);