“ flutter pub get”无法获取依赖插件

Running "flutter pub get" in flutter_tools... 775ms lib/page/home/store/storedetail/selectCouponView/selectCouponDialog.dart:5:8: Error: Error when reading '../../../../Develop/flutter/.pub-cache/hosted/pub.flutter-io.cn/flutter_widget_from_html_core-0.6.2/lib/flutter_widget_from_html_core.dart': No such file or directory import 'package:flutter_widget_from_html_core/flutter_widget_from_html_core.dart'; ^ lib/page/home/store/storedetail/selectCouponView/selectCouponDialog.dart:333:40: Error: The method 'HtmlWidget' isn't defined for the class '_SelectCouponDialogState'. - '_SelectCouponDialogState' is from 'package:xiantiansaleman/page/home/store/storedetail/selectCouponView/selectCouponDialog.dart' ('lib/page/home/store/storedetail/selectCouponView/selectCouponDialog.dart'). Try correcting the name to the name of an existing method, or defining a method named 'HtmlWidget'. child: HtmlWidget(cellData.introduction??'无'), 描述： Running "flutter pub get" in flutter_tools...