flutter image field

Flutter package enables users to upload and manage images by adding image field to a form, in addition to strong functionality to adapt images before uploading to the server and alter the widget before rendering it and a lot of other features.

Screenshot

Features

• Best structure supports the upload to a server
• localizations, override all texts
• Support multiple upload
• You can specify the limited number of image uploads
• Upload progress

Usage

1.Install Package

With Dart:

$ dart pub add image_field

With Flutter:

$ flutter pub add image_field

2.Installation

Please read the Installation of the dependent package Image Picker and do not forget to add the keys in Info.plist for IOS and in AndroidManifest.xml for Android to prevent crash the app when trying to upload or take a photo.

3.Implementation

You can use ImageField() for upload to a server by following the example below:

import 'dart:async';
import 'dart:io';

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

typedef Progress = Function(double percent);

class UploadRemoteImageForm extends StatefulWidget {
  const UploadRemoteImageForm({super.key, required this.title});
  final String title;
  @override
  State<UploadRemoteImageForm> createState() => _UploadRemoteImageFormState();
}

class _UploadRemoteImageFormState extends State<UploadRemoteImageForm> {
  // not a GlobalKey<MyCustomFormState>.
  final _formKey = GlobalKey<FormState>();

  dynamic remoteFiles;

 
  Future<dynamic> uploadToServer(XFile? file,
      {Progress? uploadProgress}) async {
    //implement your code using Rest API or other technology
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        body: Form(
          key: _formKey,
          child:  Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
        
                //Remote Image upload
                ImageField(
                    texts: const {
                      'fieldFormText': 'Upload to server',
                      'titleText': 'Upload to server'
                    },
                    files: remoteFiles != null
                        ? remoteFiles!.map((image) {
                            return ImageAndCaptionModel(
                                file: image, caption: image.alt.toString());
                          }).toList()
                        : [],
                    remoteImage: true,
                    onUpload: (pickedFile,
                                 controllerLinearProgressIndicator) async {
                      dynamic fileUploaded = await uploadToServer(
                        pickedFile,
                        uploadProgress: (percent) {
                          var uploadProgressPercentage = percent / 100;
                          controllerLinearProgressIndicator!
                              .updateProgress(uploadProgressPercentage);
                        },
                      );
                      return fileUploaded;
                    },
                    onSave: (List<ImageAndCaptionModel>? imageAndCaptionList) {
                      remoteFiles = imageAndCaptionList;
                    }),
      
              ],
            ),
     
        ));
  }
}

Simple locally upload by adding ImageField() to a form like the following example:

import 'package:flutter/material.dart';
import 'package:image_field/image_field.dart';
import 'package:image_field/linear_progress_Indicator.dart';


class UploadLocalImageForm extends StatefulWidget {
  const UploadLocalImageForm({super.key, required this.title});

  final String title;

  @override
  State<UploadLocalImageForm> createState() => _UploadLocalImageFormState();
}

class _UploadLocalImageFormState extends State<UploadLocalImageForm> {
  final _formKey = GlobalKey<FormState>();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        body: Form(
          key: _formKey,
          child:  Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                
                //...
                // textfield
                // checkbox
                // datefield
                // ....

              //Local image upload
                ImageField(onSave:(List<ImageAndCaptionModel>? imageAndCaptionList) {
                    //you can save imageAndCaptionList using local storage
                    //or in a simple variable
                },),
 
                 //....
                 //Submit button
                 //....
              ],
            ),
          ),
        );
  }
}

Main Parameters

Parameter	Type	Description
files	List	Used to add default images on load
remoteImage	Widget	Used for remote upload image, if True should implement onUpload() function
texts	Map<String, String>	key/value variable used for localizations or to override the defaults texts used by the Imagefield.
multipleUpload	bool	Enable user to pick multiple files.
enabledCaption	bool	Allow user to add a caption for a image.
cardinality	int	Maximum number of files that can be uploaded.

Main Functions

Function	Parameter	Description
onUpload	dynamic Function(dynamic, ControllerLinearProgressIndicatorIF?)?	This function has [dataSource] image that uploaded by a user to send them to the server and [controllerLinearProgressIndicator] used as a reference variable to indicate the uploading progress to the server and return the result to store it in the [fileList] that used in the field.
onSave	void Function(List?)?	Used to update the form with the uploaded files, it called when back from the listview
alterFieldForm	Widget Function(List?, Widget)?	It's a hook function used to alter the widget of the field(Thumbnail List) in the form before rendering it

License

This package is licensed under the MIT License