问错误:参数类型'PickedFile‘不能分配给参数类型'File’。颤动

EN

import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'dart:convert';
import 'package:http/http.dart' ;



class CreateProfile extends StatefulWidget {
  CreateProfile({required Key key}) : super(key: key);

  @override
  _CreateProfileState createState() => _CreateProfileState();
}

class _CreateProfileState extends State<CreateProfile> {

  bool circular = false;
  late PickedFile _imageFile;

 final ImagePicker _picker = ImagePicker();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Form(

        child: ListView(
          padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 30),
          children: <Widget>[
            imageProfile(),
            SizedBox(
              height: 20,
            ),
            nameTextField(),
            SizedBox(
              height: 20,
            ),
            professionTextField(),
            SizedBox(
              height: 20,
            ),
            dobField(),
            SizedBox(
              height: 20,
            ),
            titleTextField(),
            SizedBox(
              height: 20,
            ),
            aboutTextField(),
            SizedBox(
              height: 20,
            ),

],
    ),
    ),
    );
              }

  Widget imageProfile() {
    return Center(
      child: Stack(children: <Widget>[
        CircleAvatar(
          radius: 80.0,
          backgroundImage: _imageFile == null
              ? AssetImage("assets/pic.jpg") as ImageProvider
              : FileImage(_imageFile),

        ),
        Positioned(
          bottom: 20.0,
          right: 20.0,
          child: InkWell(
            onTap: () {
              showModalBottomSheet(
                context: context,
                builder: ((builder) => bottomSheet()),
              );
            },
            child: Icon(
              Icons.camera_alt,
              color: Colors.teal,
              size: 28.0,
            ),
          ),
        ),
      ]),
    );
  }

  Widget bottomSheet() {
    return Container(
      height: 100.0,
      width: MediaQuery.of(context).size.width,
      margin: EdgeInsets.symmetric(
        horizontal: 20,
        vertical: 20,
      ),
      child: Column(
        children: <Widget>[
          Text(
            "Choose Profile photo",
            style: TextStyle(
              fontSize: 20.0,
            ),
          ),
          SizedBox(
            height: 20,
          ),
          Row(mainAxisAlignment: MainAxisAlignment.center, children: <Widget>[
            TextButton.icon(
              icon: Icon(Icons.camera),
              onPressed: () {
                takePhoto(ImageSource.camera);
              },
              label: Text("Camera"),
            ),
            TextButton.icon(
              icon: Icon(Icons.image),
              onPressed: () {
                takePhoto(ImageSource.gallery);
              },
              label: Text("Gallery"),
            ),
          ])
        ],
      ),
    );
  }

  void takePhoto(ImageSource source) async {
    final pickedFile = await _picker.pickImage(
      source: source,
    );
    setState(() {
      _imageFile = pickedFile as PickedFile;

    });
  }

  //starting text fields

  Widget nameTextField() {
    return TextFormField(
      //controller: _name,
      validator: (value) {
        if (value!.isEmpty) return "Name can't be empty";

        return null;
      },
      decoration: InputDecoration(
        border: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.teal,
            )),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.orange,
              width: 2,
            )),
        prefixIcon: Icon(
          Icons.person,
          color: Colors.green,
        ),
        labelText: "Name",
        helperText: "Name can't be empty",
        hintText: "Dev Stack",
      ),
    );
  }

  Widget professionTextField() {
    return TextFormField(
      //controller: _profession,
      validator: (value) {
        if (value!.isEmpty) return "Profession can't be empty";

        return null;
      },
      decoration: InputDecoration(
        border: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.teal,
            )),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.orange,
              width: 2,
            )),
        prefixIcon: Icon(
          Icons.person,
          color: Colors.green,
        ),
        labelText: "Profession",
        helperText: "Profession can't be empty",
        hintText: "Full Stack Developer",
      ),
    );
  }

  Widget dobField() {
    return TextFormField(
     // controller: _dob,
      validator: (value) {
        if (value!.isEmpty) return "DOB can't be empty";

        return null;
      },
      decoration: InputDecoration(
        border: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.teal,
            )),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.orange,
              width: 2,
            )),
        prefixIcon: Icon(
          Icons.person,
          color: Colors.green,
        ),
        labelText: "Date Of Birth",
        helperText: "Provide DOB on dd/mm/yyyy",
        hintText: "01/01/2020",
      ),
    );
  }

  Widget titleTextField() {
    return TextFormField(
     // controller: _title,
      validator: (value) {
        if (value!.isEmpty) return "Title can't be empty";

        return null;
      },
      decoration: InputDecoration(
        border: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.teal,
            )),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.orange,
              width: 2,
            )),
        prefixIcon: Icon(
          Icons.person,
          color: Colors.green,
        ),
        labelText: "Title",
        helperText: "It can't be empty",
        hintText: "Flutter Developer",
      ),
    );
  }

  Widget aboutTextField() {
    return TextFormField(
     // controller: _about,
      validator: (value) {
        if (value!.isEmpty) return "About can't be empty";

        return null;
      },
      maxLines: 4,
      decoration: InputDecoration(
        border: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.teal,
            )),
        focusedBorder: OutlineInputBorder(
            borderSide: BorderSide(
              color: Colors.orange,
              width: 2,
            )),
        labelText: "About",
        helperText: "Write about yourself",
        hintText: "I am Dev Stack",
      ),
    );
  }
}