当我在释放模式下构建时，我的 Flutter 应用程序出现灰屏

Question

当我在发布模式下构建 Flutter 应用程序时，会出现这两个灰色框：

[应用程序截图][1]

上框 包含此构建代码：

 Widget build(BuildContext context) {
return  Expanded(

    child: Row(

  mainAxisAlignment: MainAxisAlignment.center,
  crossAxisAlignment: CrossAxisAlignment.center,
  textDirection: TextDirection.ltr,
  children:<Widget> [


  ValueListenableBuilder(valueListenable:placeNotify ,builder: (context,value,child){
          return Text(value.toString(),textDirection: TextDirection.ltr, textAlign: TextAlign.center,style: const TextStyle(fontSize: 20, fontWeight:FontWeight.w300,color: Colors.black45));
        },)

  ],
    ),

        );


// TODO: implement build
throw UnimplementedError();

}

底盒 包含此构建代码：我只显示顶部部分是很多代码

return Expanded(

  child: Row(
      mainAxisAlignment: MainAxisAlignment.center,
      crossAxisAlignment: CrossAxisAlignment.center,
      textDirection: TextDirection.ltr,
      children: <Widget>[


        Flexible(
            flex: 2,

            child: Column(

                crossAxisAlignment: CrossAxisAlignment.center,
                children: <Widget>[


                  Directionality(
                    textDirection: TextDirection.ltr,
                    child: DropShadow(
                      blurRadius: 10,

                      offset: const Offset(3, 3),
                      spread: 1,
                      child: Flexible(
                        flex: 2,

                        child: Container(
                          width: 200,
                          decoration: BoxDecoration(
                            color: Colors.orange[200],
                            borderRadius: BorderRadius.circular(20),
                            gradient: const LinearGradient(
                              colors: [
                                Color(0xFFEC3DEC),
                                Color(0xFF73C5ED)
                              ],
                            ),

主要构建如下所示：

 return  Container( child:Column(

    crossAxisAlignment: CrossAxisAlignment.center,
    children:<Widget> [

      SizedBox(height: 50),
      Flexible(
        flex: 1,
        child: Container(padding: const EdgeInsets.all(50),
            decoration: BoxDecoration(
                color: Colors.orange[200],
                border: Border.all(width: 2.0, color: Colors.black45)
            ),
            child: getPositionAdress()
        )
      ),

      Flexible(
        flex: 2,
        child:Container(color: Colors.cyan[100],
            padding: const EdgeInsets.all(10),
            child: Wetteddaten(),

      ) ,
      ),
      Flexible(
        flex: 2,
        child:MaterialApp(color: Colors.blue,
          title: 'Flutter Google Maps Demo',
          home: MapSample(),

        ),
      ),

这个问题已经以修改后的形式已知。有人可以向我解释避免这个问题的基本程序吗？ [1]：

Answer 1

因为扩展了widget，你可以使用Flexible widget来代替

Flexible(
 fit: FlexFit.tight,
  child: ...,
);

Answer 2

删除扩展小部件，绿屏就会消失