打印功能没有打印所有内容。
您可以使用调试模式查看完整结果
代码片段
List<int> imageBytes = await _imageFile.readAsBytes();
String base64Image = base64Encode(imageBytes);
print(base64Image);
从调试模式复制base64字符串并粘贴到在线转换器,您可以看到结果是正确的。
来自官方演示的完整代码并添加 base64 转换
// Copyright 2019 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'dart:io';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:video_player/video_player.dart';
import 'dart:typed_data';
import 'package:image/image.dart' as ImageProcess;
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Image Picker Demo',
home: MyHomePage(title: 'Image Picker Example'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
File _imageFile;
dynamic _pickImageError;
bool isVideo = false;
VideoPlayerController _controller;
String _retrieveDataError;
Future<void> _playVideo(File file) async {
if (file != null && mounted) {
await _disposeVideoController();
_controller = VideoPlayerController.file(file);
await _controller.setVolume(1.0);
await _controller.initialize();
await _controller.setLooping(true);
await _controller.play();
setState(() {});
}
}
void _onImageButtonPressed(ImageSource source) async {
if (_controller != null) {
await _controller.setVolume(0.0);
}
if (isVideo) {
final File file = await ImagePicker.pickVideo(source: source);
await _playVideo(file);
} else {
try {
_imageFile = await ImagePicker.pickImage(source: source);
List<int> imageBytes = await _imageFile.readAsBytes();
String base64Image = base64Encode(imageBytes);
print(base64Image);
setState(() {});
} catch (e) {
_pickImageError = e;
}
}
}
@override
void deactivate() {
if (_controller != null) {
_controller.setVolume(0.0);
_controller.pause();
}
super.deactivate();
}
@override
void dispose() {
_disposeVideoController();
super.dispose();
}
Future<void> _disposeVideoController() async {
if (_controller != null) {
await _controller.dispose();
_controller = null;
}
}
Widget _previewVideo() {
final Text retrieveError = _getRetrieveErrorWidget();
if (retrieveError != null) {
return retrieveError;
}
if (_controller == null) {
return const Text(
'You have not yet picked a video',
textAlign: TextAlign.center,
);
}
return Padding(
padding: const EdgeInsets.all(10.0),
child: AspectRatioVideo(_controller),
);
}
Widget _previewImage() {
final Text retrieveError = _getRetrieveErrorWidget();
if (retrieveError != null) {
return retrieveError;
}
if (_imageFile != null) {
return Image.file(_imageFile);
} else if (_pickImageError != null) {
return Text(
'Pick image error: $_pickImageError',
textAlign: TextAlign.center,
);
} else {
return const Text(
'You have not yet picked an image.',
textAlign: TextAlign.center,
);
}
}
Future<void> retrieveLostData() async {
final LostDataResponse response = await ImagePicker.retrieveLostData();
if (response.isEmpty) {
return;
}
if (response.file != null) {
if (response.type == RetrieveType.video) {
isVideo = true;
await _playVideo(response.file);
} else {
isVideo = false;
setState(() {
_imageFile = response.file;
});
}
} else {
_retrieveDataError = response.exception.code;
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Platform.isAndroid
? FutureBuilder<void>(
future: retrieveLostData(),
builder: (BuildContext context, AsyncSnapshot<void> snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
case ConnectionState.waiting:
return const Text(
'You have not yet picked an image.',
textAlign: TextAlign.center,
);
case ConnectionState.done:
return isVideo ? _previewVideo() : _previewImage();
default:
if (snapshot.hasError) {
return Text(
'Pick image/video error: ${snapshot.error}}',
textAlign: TextAlign.center,
);
} else {
return const Text(
'You have not yet picked an image.',
textAlign: TextAlign.center,
);
}
}
},
)
: (isVideo ? _previewVideo() : _previewImage()),
),
floatingActionButton: Column(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
FloatingActionButton(
onPressed: () {
isVideo = false;
_onImageButtonPressed(ImageSource.gallery);
},
heroTag: 'image0',
tooltip: 'Pick Image from gallery',
child: const Icon(Icons.photo_library),
),
Padding(
padding: const EdgeInsets.only(top: 16.0),
child: FloatingActionButton(
onPressed: () {
isVideo = false;
_onImageButtonPressed(ImageSource.camera);
},
heroTag: 'image1',
tooltip: 'Take a Photo',
child: const Icon(Icons.camera_alt),
),
),
Padding(
padding: const EdgeInsets.only(top: 16.0),
child: FloatingActionButton(
backgroundColor: Colors.red,
onPressed: () {
isVideo = true;
_onImageButtonPressed(ImageSource.gallery);
},
heroTag: 'video0',
tooltip: 'Pick Video from gallery',
child: const Icon(Icons.video_library),
),
),
Padding(
padding: const EdgeInsets.only(top: 16.0),
child: FloatingActionButton(
backgroundColor: Colors.red,
onPressed: () {
isVideo = true;
_onImageButtonPressed(ImageSource.camera);
},
heroTag: 'video1',
tooltip: 'Take a Video',
child: const Icon(Icons.videocam),
),
),
],
),
);
}
Text _getRetrieveErrorWidget() {
if (_retrieveDataError != null) {
final Text result = Text(_retrieveDataError);
_retrieveDataError = null;
return result;
}
return null;
}
}
class AspectRatioVideo extends StatefulWidget {
AspectRatioVideo(this.controller);
final VideoPlayerController controller;
@override
AspectRatioVideoState createState() => AspectRatioVideoState();
}
class AspectRatioVideoState extends State<AspectRatioVideo> {
VideoPlayerController get controller => widget.controller;
bool initialized = false;
void _onVideoControllerUpdate() {
if (!mounted) {
return;
}
if (initialized != controller.value.initialized) {
initialized = controller.value.initialized;
setState(() {});
}
}
@override
void initState() {
super.initState();
controller.addListener(_onVideoControllerUpdate);
}
@override
void dispose() {
controller.removeListener(_onVideoControllerUpdate);
super.dispose();
}
@override
Widget build(BuildContext context) {
if (initialized) {
return Center(
child: AspectRatio(
aspectRatio: controller.value?.aspectRatio,
child: VideoPlayer(controller),
),
);
} else {
return Container();
}
}
}