如果你有全屏或固定大小的showModalBottomSheet，不要使用填充，这不会解决你的问题。使用边距代替填充，就像这样:

  showModalBottomSheet(
          context: context,
          builder: (context) {
            return Container(
                marign: EdgeInsets.only(
                    bottom: MediaQuery.of(context).viewInsets.bottom),
                child: TextField()
            );
          }); 

在结合不同的解决方案后，我得到了这个:

如果你不想全屏，也不想使用填充

  showModalBottomSheet(
      context: context,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.vertical(top: Radius.circular(20)),
      ),
      enableDrag: true,
      isDismissible: true,
      useRootNavigator: true,
      builder: (BuildContext ctx) {
        return Scaffold( // use CupertinoPageScaffold for iOS
          backgroundColor: Colors.transparent,
          resizeToAvoidBottomInset: true, // important
          body: SingleChildScrollView(
            child: Form(
              child: Container(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.stretch,
                  children: <Widget>[
                    TextFormField(),
                    TextFormField(),
                  ],
                ),
              ),
            ),
          ),
        );
      },
    );

在Flutter(通道母版，v1.15.3-pre。37，适用于Mac OS X 10.15.2 19C57, locale en-US)

给那些不能解决问题的人尝试所有的答案。这些答案是正确的，但不太清楚。

当使用

MediaQuery.of(上下文).viewInsets.bottom)

make sure your context variable is using the one provided by bottom sheet builder property.

c builder:(* * * *) = > MediaQuery.of (c * * * *)

import 'dart:async'; import 'dart:ui'; import 'package:flutter/foundation.dart'; import 'package:flutter/widgets.dart'; import 'package:flutter/material.dart'; import '../weight/boostrap/flutter_bootstrap.dart'; import '../weight/boostrap/bootstrap_widgets.dart'; /* TextEditingController txtname = TextEditingController(); showModalBottomSheet( context: context, isScrollControlled: true, shape: const RoundedRectangleBorder( borderRadius: BorderRadius.only( topLeft: Radius.circular(20), topRight: Radius.circular(20), ), ), builder: (context) => SingleChildScrollView( padding: EdgeInsets.only( bottom: MediaQuery.of(context).padding.bottom), child: new AddItem( tektk: 'Category', tektd: 'Add', txtname: txtname, ismultik:false, onPressed: () {}), ), ); */ class AddItem extends StatelessWidget { const AddItem( {Key? key, required this.ismultik, required this.tektd, required this.tektk, required this.txtname, required this.onPressed}) : super(key: key); final bool ismultik; final String tektk; final String tektd; final VoidCallback? onPressed; final TextEditingController txtname; @override Widget build(BuildContext context) { final MediaQueryData mediaQueryData = MediaQuery.of(context); bootstrapGridParameters(gutterSize: 10); return Padding( padding: mediaQueryData.viewInsets, child: Container( padding: EdgeInsets.only(bottom: 90.0, left: 10.0, right: 10.0), child: Column( crossAxisAlignment: CrossAxisAlignment.stretch, mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [ ListTile( trailing: SizedBox.fromSize( size: Size(35, 35), child: ClipOval( child: Material( color: Colors.indigo, child: InkWell( splashColor: Colors.white, onTap: () { Navigator.pop(context); }, child: Column( mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[ Icon(Icons.close, color: Colors.white), ], ), ), ), ), ), ), BootstrapRow(height: 0, children: [ BootstrapCol( sizes: 'col-md-12', child: TextField( style: TextStyle(color: Colors.black), decoration: new InputDecoration( border: new OutlineInputBorder( borderSide: new BorderSide(color: Colors.white)), labelText: tektk, ), keyboardType: ismultik == true ? TextInputType.multiline : TextInputType.text, maxLines: null, minLines: 1, controller: txtname, ), ), BootstrapCol( sizes: 'col-md-12', child: ElevatedButton( style: ElevatedButton.styleFrom( primary: Colors.green, // background onPrimary: Colors.white, // foreground ), onPressed: onPressed, child: Text(tektd)), ), ]), ], ), ), ); } }

更新2021年5月扑动2.2! 现在你需要给底部填充。下面写的是一个错误。

更新2020 !

这个答案是正确的，但是你现在不需要给底部填充! 找到并删除这一行:

填充:MediaQuery.of .viewInsets(上下文)

用脚手架小部件包装表单，然后用SingleChildScrollView包装TextFormField:

 return Container(
          height: screenHeight * .66,
          child: Scaffold(
             body: Form(
               key: _form,
               child: SingleChildScrollView(
                 child:TextFormField()
               )
              )
             )
           )