无限滚动listview-在构建过程中调用setState（）或markNeedsBuild

更改

_loadNames() {

至

_loadNames(){   loading = true;   // setState(() {     _loadingState = 'loading...';   // });

和

     onRefresh: (){       _loadNames();       return null;     },

至

     onRefresh: (){       setState(() => _loadNames());     },

更新

_loadNames(){   loading = true;   new Future.delayed(Duration.zero, () => setState(() {     _loadingState = 'loading...';   }));