颤振状态窗口小部件未更新

Question

我想将一本书添加为书签，如果单击“收藏夹”按钮，则会添加该书，但是当我转到另一个窗口并返回时，图标按钮会更改颜色。

              CupertinoButton(
                    child: Icon(
                      widget.book.starred
                          ?
                           CupertinoIcons.heart_solid
                          : CupertinoIcons.heart,
                      color: Colors.red,
                    ),
                    onPressed: () {
                      setState(() {
                        widget.book.starred = !widget.book.starred;
                      addToFavorites(this.book);
                      });
               })//Cupertino Button

如何处理build方法来读取widget.book.starred的值，然后打印正确的图标？

编辑 显示更多代码

class ReadBook extends StatefulWidget {
   Book book;

   ReadBook({Key key, this.book}) : super(key: key);

  @override
  State<StatefulWidget> createState() {
    return new ReadBookState(this.book);
  }
}

class ReadBookState extends State<ReadBook> {
  // Declare a field that holds the Todo
   Book book;
      bool res;

  final controller = new PageController(initialPage: 0, keepPage: true);
  static const IconData baseball = const IconData(0xf397,
      fontFamily: CupertinoIcons.iconFont,
      fontPackage: CupertinoIcons.iconFontPackage);
  ReadBookState(this.book);
  initState() {
    super.initState();
  }


  void addToFavorites(Book book) async {

      Database.checkBookExist(book).then((value) {
        if (!value) {
          print("${widget.book.englishName} added successfully");
          Database.addBookToFirestore(widget.book);
        } else {
          print("${widget.book.englishName} already added");
        }
      });

  @override
  Widget build(BuildContext context) {
    Widget toRet;
    bool rest = retrieveFromFavorites(book);

    if (Platform.isAndroid) {
      // Android-specific code
      toRet =  MaterialApp(
          home: Scaffold(
              appBar: AppBar(
                leading: IconButton(
                  icon: Icon(Icons.arrow_back),
                  onPressed: () => Navigator.pop(context, false),
                ),
                actions: <Widget>[],
                backgroundColor: Color.fromRGBO(245, 205, 121, 1.0),
                title: Text(book.name,
                    textDirection: TextDirection.rtl,
                    style:
                        TextStyle(fontSize: 35.0, fontFamily: 'SCHEHERAZADE')),
              ),
              body: new ListView(
                controller: controller,
                scrollDirection: Axis.vertical,
                children: <Widget>[
                  new Center(
                      child: new Text(("Title"),
                          textDirection: TextDirection.rtl,
                          style: TextStyle(
                              fontSize: 35.0, fontFamily: 'SCHEHERAZADE'))),
                  new Center(
                      child: new Text((t1 + t2),
                          textDirection: TextDirection.rtl,
                          style: TextStyle(
                              fontSize: 25.0, fontFamily: 'SCHEHERAZADE')))
                ],
              )));
    } else if (Platform.isIOS) {
      // iOS-specific code
      toRet =  CupertinoApp(
        home: CupertinoPageScaffold(
          navigationBar: CupertinoNavigationBar(
            backgroundColor: Color.fromRGBO(245, 205, 121, 1.0),
            leading: CupertinoButton(
              padding: EdgeInsets.only(right: 25.0, bottom: 8.0),
              child: Icon(
                CupertinoIcons.back,
                color: Colors.black,
              ),
              onPressed: () => Navigator.pop(context, false),
            ),
            trailing: Row(
              mainAxisSize: MainAxisSize.min,
              children: <Widget>[
                CupertinoButton(
                    child: Icon(
                      widget.book.starred
                          ?
                           CupertinoIcons.heart_solid
                          : CupertinoIcons.heart,
                      color: Colors.red,
                    ),
                    onPressed: () {
                      //  PopupMenuButton
                      setState(() {
                        widget.book.starred = !widget.book.starred;
                      addToFavorites(this.book);
                      });
                    }),
                CupertinoButton(
                    child: Icon(
                      baseball,
                      color: Colors.black,
                    ),
                    onPressed: () =>
                        //  PopupMenuButton
                        popUpOptionsButton()),
              ],
            ),
            middle: Text(book.name),
          ),
          child: new ListView(
            controller: controller,
            scrollDirection: Axis.vertical,
            children: <Widget>[
              new Center(
                  child: new Text(("Title"),
                      textDirection: TextDirection.rtl,
                      style: TextStyle(
                          fontSize: 35.0, fontFamily: 'SCHEHERAZADE'))),
              new Center(
                  child: new Text((t1 + t2),
                      textDirection: TextDirection.rtl,
                      style: TextStyle(
                          fontSize: 25.0, fontFamily: 'SCHEHERAZADE')))
            ],
          ),
        ),
      );
    }
    return toRet;
  }
}