简单的解决方案，你可以自定义这个:

Container(
          margin: EdgeInsets.only(left: 15),
          child: InkWell(
              onTap: () {
                showModalBottomSheet(
                    isScrollControlled : true,
                    context: context,
                    backgroundColor: Colors.transparent,
                    builder: (context) {
                      return Container(
                        padding: EdgeInsets.only(top: 15, left: 15, right: 15, bottom: 10),
                        width: double.infinity,
                        decoration: BoxDecoration(
                          color: AppTheme.leadItemColor1,
                          borderRadius: BorderRadius.only(topLeft: Radius.circular(12), topRight: Radius.circular(12)),
                        ),
                        child: Column(
                          children: [
                            _assignTo(widget.viewModel, context),
                            SizedBox(height: 12,),
                            txtComment(widget.viewModel),
                            SizedBox(height: 12,),
                            CRMButton(
                              title: 'Select',
                              onTap: () async {
                                Navigator.pop(context);
                                await widget.viewModel.updateStatus(7, why: "${ConstantData.lostOptions[_selectedNumber]}");
                              },
                            )
                          ],
                        ),
                      );
                    },
                );
              },
              child: CustomTabBarItem1(
                image: widget.viewModel.leadDetail.success.lStatus == 7 ? 'assets/appimages/LeadDetail/icons-03-01.png' : 'assets/appimages/LeadDetail/icons-04-01.png',
                bottomTitle: 'Lost',
                topTitle: widget.viewModel.leadDetail.success.lStatus > 7 ? 'assets/appimages/LeadDetail/Ellipse 61@2x.png' : widget.viewModel.leadDetail.success.lStatus == 7 ? 'assets/appimages/LeadDetail/Group 486-1.png' : 'assets/appimages/LeadDetail/Ellipse-61@3x.png',
                height : widget.viewModel.leadDetail.success.lStatus == 7 ? "0" : "1",
              )),
        ),

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()
               )
              )
             )
           )

showModalBottomSheet(
 isScrollControlled: true,
 builder: (BuildContext context) {

    return SingleChildScrollView(
      child: Container(
        padding:
            EdgeInsets.only(bottom: MediaQuery.of(context).viewInsets.bottom),
        child: Padding(
          padding: const EdgeInsets.all(15.0), // content padding
          child: Container())});

注意:这一行完成了所有的魔术

试试这个。

showModalBottomSheet(
        isScrollControlled: true,
        context: context,
        builder: (context) {
          return AnimatedPadding(
              padding: MediaQuery.of(context).viewInsets,
              duration: const Duration(milliseconds: 100),
              curve: Curves.decelerate,
              child: Container(
                  child: Wrap(
                children: [
                  TextField(
                    decoration: InputDecoration(labelText: "1"),
                  ),
                  TextField(
                    decoration: InputDecoration(labelText: "2"),
                  ),
                  TextField(
                    decoration: InputDecoration(labelText: "3"),
                  ),
                ],
              )));
        },
      )

showModalBottomSheet(
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(15.0),
      ),
      context: context,
      isScrollControlled: true,
      builder: (builder) {
        return Container(
          height: MediaQuery.of(context).size.height - 40,
          padding: MediaQuery.of(context).viewInsets,
          child: <Your Widget Here>,
        );
      },
    );

把它添加到你的底页的最后一个小部件之后

Padding(padding: EdgeInsets.only(bottom:MediaQuery.of(context).viewInsets.bottom))