在颤动中将图像从图像选择器保存到firebase存储

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【中文标题】在颤动中将图像从图像选择器保存到firebase存储【英文标题】:Save Image from Image picker to firebase Storage in flutter 【发布时间】:2020-12-13 16:44:14 【问题描述】:

我正在尝试在 firebase 存储中上传图像,通过访问相机从图像选择器插件中获取图像。图片未上传。我还补充说我更改了 Firebase 规则,因此只有经过身份验证的用户才能上传图像。 Git 中心Repo。我使用了 auth_screen.dart 第 48 到 59 行[我暂时注释掉] 处定义的图片上传逻辑。当我添加这些行时,我还添加了我之前运行良好的其他 firebase 功能。得到错误。

auth_screen.dart

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_auth/firebase_auth.dart';

// import 'package:firebase_storage/firebase_storage.dart';

import 'package:flutter/services.dart';
import '../widgets/auth/auth_form.dart';

class AuthScreen extends StatefulWidget 
  @override
  _AuthScreenState createState() => _AuthScreenState();


class _AuthScreenState extends State<AuthScreen> 
  final _auth = FirebaseAuth.instance;
  var _isLoading = false;

  void _submitAuthForm(
    String email,
    String password,
    String userName,
    File userImage,
    bool isLogin,
    BuildContext ctx,
  ) async 
    dynamic authResult;
    try 
      setState(() 
        _isLoading = true;
      );
      if (isLogin) 
        authResult = await _auth.signInWithEmailAndPassword(
          email: email,
          password: password,
        );
       else 
        print(email);
        print(userName);
        print(userImage.path);
        authResult = await _auth.createUserWithEmailAndPassword(
          email: email,
          password: password,
        );

        // final FirebaseStorage storage = FirebaseStorage(
        //   app: FirebaseStorage.instance.app,
        //   storageBucket: 'gs://chatapp-1b780.appspot.com',
        // );

        // final StorageReference ref2 =
        //     storage.ref().child('userimage').child('$authResult.user.id.jpg');
        // final StorageUploadTask uploadTask = ref2.putFile(userImage);
        // uploadTask.onComplete
        //     .then((value) => print(value))
        //     .catchError((error) => print(error));
        // print(uploadTask.lastSnapshot.error.toString());

        // ///...
        // final ref = FirebaseStorage.instance
        //     .ref()
        //     .child('user_image')
        //     .child(authResult.user.id + '.jpg');
        // await ref.putFile(userImage).onComplete;

        ///
        await FirebaseFirestore.instance
            .collection('users')
            .doc(authResult.user.uid)
            .set(
          'username': userName,
          'email': email,
        );
      
     on PlatformException catch (error) 
      var message = 'An error occured,Please check your credentials';
      if (error.message != null) 
        setState(() 
          _isLoading = false;
        );
        message = error.message;
      
      print(message);
     catch (error) 
      setState(() 
        _isLoading = false;
      );
      Scaffold.of(ctx).showSnackBar(
        SnackBar(
          content: Text(error.toString()),
          backgroundColor: Theme.of(ctx).errorColor,
        ),
      );
    
  

  @override
  Widget build(BuildContext context) 
    return Scaffold(
      backgroundColor: Theme.of(context).primaryColor,
      body: AuthForm(_submitAuthForm, _isLoading),
    );
  


使用图像选择器从 auth/auth_form.dartuser_image_picker.dart 选择图像,我在其中添加了参数,以便将图像传递下来。 auth/authform.dart

import 'package:flutter/material.dart';
import 'dart:io';

import '../pickers/user_image_picker.dart';

class AuthForm extends StatefulWidget 
  final bool isLoading;
  final void Function(String email, String password, String userName,
      File userImage, bool isLogin, BuildContext ctx) submitFn;
  AuthForm(this.submitFn, this.isLoading);
  @override
  _AuthFormState createState() => _AuthFormState();


class _AuthFormState extends State<AuthForm> 
  final _formKey = GlobalKey<FormState>();
  var _isLogin = true;

  String _userEmail = '';
  String _userName = '';
  String _userPassword = '';
  File _userImageFile;
  void _pickedImage(File image) 
    _userImageFile = image;
  

  void _trysubmit() 
    final isValid = _formKey.currentState.validate();
    FocusScope.of(context).unfocus();
    if (_userImageFile == null && !_isLogin) 
      Scaffold.of(context).showSnackBar(
        SnackBar(
          content: Text('Please Pick an Image'),
          backgroundColor: Theme.of(context).errorColor,
        ),
      );
      return;
    
    if (isValid) 
      _formKey.currentState.save();
      print(_userEmail);
      print(_userPassword);
      widget.submitFn(_userEmail.trim(), _userPassword.trim(), _userName.trim(),
          _userImageFile, _isLogin, context);
      print(_userEmail);
      print(_userPassword);
    
  

  @override
  Widget build(BuildContext context) 
    return Center(
      child: Card(
        margin: EdgeInsets.all(20),
        child: SingleChildScrollView(
          child: Padding(
            padding: EdgeInsets.all(16),
            child: Form(
              key: _formKey,
              child: SingleChildScrollView(
                child: Column(
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[
                    if (!_isLogin)
                      UserImagePicker(
                        imagePickFn: _pickedImage,
                        
                      ),
                    TextFormField(
                      key: ValueKey('emailAdress'),
                      keyboardType: TextInputType.emailAddress,
                      decoration: InputDecoration(
                        labelText: 'Email address',
                      ),
                      validator: (value) 
                        if (value.isEmpty || !value.contains('@')) 
                          return 'Please return a valid email address';
                        
                        return null;
                      ,
                      onSaved: (newValue) 
                        _userEmail = newValue;
                      ,
                    ),
                    if (!_isLogin)
                      TextFormField(
                        key: ValueKey('userName'),
                        decoration: InputDecoration(labelText: 'Username'),
                        validator: (value) 
                          if (value.isEmpty || value.length < 4) 
                            return 'Please Enter at least 4 characters';
                          
                          return null;
                        ,
                        onSaved: (newValue) 
                          _userName = newValue;
                        ,
                      ),
                    TextFormField(
                      key: ValueKey('password'),
                      decoration: InputDecoration(labelText: 'Password'),
                      obscureText: true,
                      validator: (value) 
                        if (value.isEmpty || value.length < 7) 
                          return 'Please Enter at least 7 characters';
                        
                        return null;
                      ,
                      onSaved: (newValue) 
                        _userPassword = newValue;
                      ,
                    ),
                    SizedBox(
                      height: 12,
                    ),
                    if (widget.isLoading) CircularProgressIndicator(),
                    if (!widget.isLoading)
                      RaisedButton(
                        onPressed: _trysubmit,
                        child: Text((_isLogin) ? 'Login' : 'SignUp'),
                      ),
                    if (!widget.isLoading)
                      FlatButton(
                        textColor: Theme.of(context).primaryColor,
                        child: Text(_isLogin
                            ? 'Create new account'
                            : 'I already have an account'),
                        onPressed: () 
                          setState(() 
                            _isLogin = !_isLogin;
                          );
                        ,
                      ),
                  ],
                ),
              ),
            ),
          ),
        ),
      ),
    );
  


user_image_picker.dart

import 'dart:io';

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';

class UserImagePicker extends StatefulWidget 
  UserImagePicker(this.imagePickFn);
  final void Function(File pickedImage) imagePickFn;
  @override
  _UserImagePickerState createState() => _UserImagePickerState();


class _UserImagePickerState extends State<UserImagePicker> 
  File _image;
  final picker = ImagePicker();

  Future<void> getImage() async 
    final pickedFile = await ImagePicker().getImage(source: ImageSource.camera);

    setState(() 
      _image = File(pickedFile.path);
    );
    widget.imagePickFn(_image);
  

  @override
  Widget build(BuildContext context) 
    return Column(
      children: [
        CircleAvatar(
          radius: 40,
          backgroundColor: Colors.grey,
          backgroundImage: _image != null ? FileImage(_image) : null,
        ),
        FlatButton.icon(
          onPressed: getImage,
          icon: Icon(Icons.image),
          label: Text('Add Image'),
          textColor: Theme.of(context).primaryColor,
        ),
      ],
    );
  


【问题讨论】:

你可以在这里发布你的代码而不是你的 Github 仓库的链接吗?有些人如果看不到您的代码,就会对您的帖子投反对票。 @Uni 我上传了发生错误的文件。或者我需要上传项目的所有文件 使用图像选取器选取的图像在哪里? 我真的不明白哪里错了,我能做些什么来帮助你。你想让我告诉你我是如何将图像上传到 Firebase 存储的吗? 你能告诉我如何将图像上传到 Firebase 存储,仅供经过身份验证的用户使用。@Uni 【参考方案1】:

既然你让我教你如何将图片上传到Firebase Storage,我会告诉你整个过程,包括使用Image Picker插件。这就是你应该如何使用图像选择器:

class PickMyImage
static Future<File> getImage() async 
    final image = await ImagePicker().getImage(
      source: ImageSource.gallery,
      maxHeight: 1500,
      maxWidth: 1500,
    );
    if (image != null) 
      return File(image.path);
    
    return null;
  
  

您可以通过以下方式获取该图像并将其上传到 Firebase 存储:

   final File _myImage=await PickMyImage.getImage();
   if(_myImage!=null)
      final StorageReference firebaseStorageRef = FirebaseStorage.instance
          .ref()
          .child("user/$_auth.currentUser().uid/i"); //i is the name of the image
      StorageUploadTask uploadTask =
          firebaseStorageRef.putFile(_myImage);
      StorageTaskSnapshot storageSnapshot = await uploadTask.onComplete;
      var downloadUrl = await storageSnapshot.ref.getDownloadURL();
      if (uploadTask.isComplete) 
        final String url = downloadUrl.toString();
        print(url);
        //You might want to set this as the _auth.currentUser().photourl
       else 
        //error uploading
      
    

【讨论】:

能否添加firebase storage和imagePicker的插件版本。 这里是:image_picker: ^0.6.7+5 and firebase_storage: ^3.1.6 我认为即使是最新版本也可以在这里使用。 是的,最新版本有效..我解决了这个问题..谢谢【参考方案2】:

我遇到的问题是因为我返回文件的 ImagePicker() 函数,然后从相机获取图像,然后将文件传递到 Fire Storage 存储桶。 在 user_image_picker.dart 我写了这个 final pickedFile = await ImagePicker().getImage(source: ImageSource.camera); 而不是我必须写这个 final pickedFile = await picker.getImage(source: ImageSource.camera);

【讨论】:

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