问题
I am clicking images using the image_picker package and the images are returned as a File Type, I am storing all the images I click in a list of type File( because image_picker is returning a File ). Now i want to convert all the images into one pdf, for this i am using the pdf package. So, how do i do that, in the documentation they showed the way only for Text and Image, i need to know how to add files in a pdf.
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'dart:io';
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;
class Home extends StatefulWidget {
@override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
List<File> _files = [];
final pdf = pw.Document();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Home"),
centerTitle: true,
),
body: Stack(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: new GridView.builder(
itemCount: _files.length,
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 3,
),
itemBuilder: (context, index) {
return displaySelectedFile(_files[index]);
},
),
),
Positioned(
left: 30.0,
bottom: 18.0,
child: RaisedButton(
onPressed: () {
for (var i = 0; i < _files.length; i++) {
pdf.addPage(pw.Page(
pageFormat: PdfPageFormat.a4,
build: (pw.Context context) {
return pw.Center(child: pw.Image(_files[i]));
}));
}
},
color: Colors.blue,
child: Text(
'Get PDF',
style: TextStyle(color: Colors.white),
),
),
),
],
),
floatingActionButton: FloatingActionButton(
onPressed: () async {
File cameraFile;
print('Pressed');
cameraFile = await ImagePicker.pickImage(source: ImageSource.camera);
print(cameraFile.path);
List<File> temp = _files;
temp.add(cameraFile);
setState(() {
_files = temp;
});
},
child: Icon(Icons.camera_alt),
),
);
}
Widget displaySelectedFile(File file) {
return Padding(
padding: const EdgeInsets.all(4.0),
child: SizedBox(
height: 200.0,
width: 200.0,
child: Image.file(file),
),
);
}
}
this is my pubspec.yaml
name: prototype
description: A new Flutter project.
# The following line prevents the package from being accidentally published to
# pub.dev using `pub publish`. This is preferred for private packages.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev
# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1
environment:
sdk: ">=2.7.0 <3.0.0"
dependencies:
flutter:
sdk: flutter
image_picker: ^0.6.7+3
pdf: ^1.9.0
# The following adds the Cupertino Icons font to your application.
# Use with the CupertinoIcons class for iOS style icons.
cupertino_icons: ^0.1.3
dev_dependencies:
flutter_test:
sdk: flutter
# For information on the generic Dart part of this file, see the
# following page: https://dart.dev/tools/pub/pubspec
# The following section is specific to Flutter.
flutter:
# The following line ensures that the Material Icons font is
# included with your application, so that you can use the icons in
# the material Icons class.
uses-material-design: true
# To add assets to your application, add an assets section, like this:
# assets:
# - images/a_dot_burr.jpeg
# - images/a_dot_ham.jpeg
# An image asset can refer to one or more resolution-specific "variants", see
# https://flutter.dev/assets-and-images/#resolution-aware.
# For details regarding adding assets from package dependencies, see
# https://flutter.dev/assets-and-images/#from-packages
# To add custom fonts to your application, add a fonts section here,
# in this "flutter" section. Each entry in this list should have a
# "family" key with the font family name, and a "fonts" key with a
# list giving the asset and other descriptors for the font. For
# example:
# fonts:
# - family: Schyler
# fonts:
# - asset: fonts/Schyler-Regular.ttf
# - asset: fonts/Schyler-Italic.ttf
# style: italic
# - family: Trajan Pro
# fonts:
# - asset: fonts/TrajanPro.ttf
# - asset: fonts/TrajanPro_Bold.ttf
# weight: 700
#
# For details regarding fonts from package dependencies,
# see https://flutter.dev/custom-fonts/#from-packages
回答1:
try this
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'dart:io';
import 'package:pdf/pdf.dart';
import 'package:pdf/widgets.dart' as pw;
class Home extends StatefulWidget {
@override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
List<File> _files = [];
final pdf = pw.Document();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Home"),
centerTitle: true,
),
body: Stack(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: new GridView.builder(
itemCount: _files.length,
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 3,
),
itemBuilder: (context, index) {
return displaySelectedFile(_files[index]);
},
),
),
Positioned(
left: 30.0,
bottom: 18.0,
child: RaisedButton(
onPressed: () {
for (var i = 0; i < _files.length; i++) {
// added this
var image = PdfImage.file(
pdf.document,
bytes: File(_files[i].path).readAsBytesSync(),
);
pdf.addPage(pw.Page(
pageFormat: PdfPageFormat.a4,
build: (pw.Context context) {
return pw.Center(child: pw.Image(image);
}));
}
},
color: Colors.blue,
child: Text(
'Get PDF',
style: TextStyle(color: Colors.white),
),
),
),
],
),
floatingActionButton: FloatingActionButton(
onPressed: () async {
File cameraFile;
print('Pressed');
cameraFile = await ImagePicker.pickImage(source: ImageSource.camera);
print(cameraFile.path);
List<File> temp = _files;
temp.add(cameraFile);
setState(() {
_files = temp;
});
},
child: Icon(Icons.camera_alt),
),
);
}
Widget displaySelectedFile(File file) {
return Padding(
padding: const EdgeInsets.all(4.0),
child: SizedBox(
height: 200.0,
width: 200.0,
child: Image.file(file),
),
);
}
}
来源：https://stackoverflow.com/questions/62703237/convert-images-clicked-from-your-phone-to-pdf-in-flutter-using-image-clicker-and