Android MyAppState没有显示任何内容 导入'dart:async'; 导入“dart:io”; 导入“dart:键入的_数据”; 进口“包装:颤振/cupertino.dart”; 进口“包装:颤振/材料.省道”; 导入“package:shared_pr
MyAppState没有显示任何内容Android MyAppState没有显示任何内容 导入'dart:async'; 导入“dart:io”; 导入“dart:键入的_数据”; 进口“包装:颤振/cupertino.dart”; 进口“包装:颤振/材料.省道”; 导入“package:shared_pr,android,flutter,dart,flutter-layout,dart-pub,Android,Flutter,Dart,Flutter Layout,Dart Pub,MyAppState没有显示任何内容 导入'dart:async'; 导入“dart:io”; 导入“dart:键入的_数据”; 进口“包装:颤振/cupertino.dart”; 进口“包装:颤振/材料.省道”; 导入“package:shared_preferences/shared_preferences.dart”; 导入“package:image_gallery_saver/image_gallery_saver.dart”; 导入“包:image_picker/image_pick
导入'dart:async';
导入“dart:io”;
导入“dart:键入的_数据”;
进口“包装:颤振/cupertino.dart”;
进口“包装:颤振/材料.省道”;
导入“package:shared_preferences/shared_preferences.dart”;
导入“package:image_gallery_saver/image_gallery_saver.dart”;
导入“包:image_picker/image_picker.dart”;
导入“package:qrscan/qrscan.dart”作为扫描仪;
void main(){
runApp(MyApp());
}
类MyApp扩展了StatefulWidget{
@凌驾
_MyAppState createState()=>\u MyAppState();
}
类MyAppState扩展了状态{
Uint8List字节=Uint8List(0);
TextEditingController\u输入控制器;
TextEditingController\u输出控制器;
@凌驾
initState(){
super.initState();
这是._inputController=新文本编辑控制器();
这是._outputController=新文本编辑控制器();
}
@凌驾
小部件构建(构建上下文){
返回材料PP(
debugShowCheckedModeBanner:false,
家:脚手架(
背景颜色:颜色。灰色[300],
车身:建造商(
生成器:(BuildContext上下文){
返回列表视图(
儿童:[
_qrCodeWidget(this.bytes,context),
容器(
颜色:颜色,白色,
子:列(
儿童:[
文本字段(
控制器:此。\u输入控制器,
键盘类型:TextInputType.url,
textInputAction:textInputAction.go,
提交时:(值)=>_generateBarCode(值),
装饰:输入装饰(
前缀:图标(图标、文本字段),
helperText:“请将您的代码输入到generage qrcode图像。”,
hintText:'请输入您的代码',
hintStyle:TextStyle(字体大小:15),
contentPadding:EdgeInsets.symmetric(
水平:7,垂直:15),
),
),
尺寸箱(高度:20),
文本字段(
控制器:这个输出控制器,
maxLines:2,
装饰:输入装饰(
前缀图标:图标(图标.换行文字),
helperText:“您扫描的条形码或QR码将显示在此区域。”,
hintText:'您扫描的条形码或QR码将显示在此区域。',
hintStyle:TextStyle(字体大小:15),
contentPadding:EdgeInsets.symmetric(
水平:7,垂直:15),
),
),
尺寸箱(高度:20),
这是。_buttonGroup(),
尺寸箱(高度:70),
],
),
),
],
);
},
),
浮动操作按钮:浮动操作按钮(
按下时:()=>\u scanBytes(),
工具提示:“拍照”,
子项:常量图标(Icons.camera_alt),
),
),
);
}
Widget\u qrCodeWidget(Uint8List字节,BuildContext上下文){
返回填充(
填充:边缘设置。全部(20),
孩子:卡片(
标高:6,
子:列(
儿童:[
容器(
孩子:排(
crossAxisAlignment:crossAxisAlignment.end,
儿童:[
图标(Icons.u用户,尺寸:18,颜色:Colors.green),
文本('Generate Qrcode',样式:TextStyle(fontSize:15)),
垫片(),
图标(Icons.more_vert,大小:18,颜色:Colors.black54),
],
),
填充:边缘组。对称(水平:10,垂直:9),
装饰:盒子装饰(
颜色:颜色。黑色,
borderRadius:仅限borderRadius(
左上角:半径。圆形(4),右上角:半径。圆形(4)),
),
),
填充物(
填充:仅限边缘设置(
左:40,右:40,顶部:30,底部:10),
子:列(
儿童:[
大小盒子(
身高:190,
子项:bytes.isEmpty
?中心(
子项:文本('空代码…',
样式:TextStyle(颜色:Colors.black38)),
)
:Image.memory(字节),
),
填充物(
填充:仅限边缘设置(顶部:7,左侧:25,右侧:25),
孩子:排(
mainAxisAlignment:mainAxisAlignment.spaceAround,
儿童:[
扩大(
弹性:5,
儿童:手势检测器(
子:文本(
“删除”,
样式:TextStyle(
字体大小:15,颜色:颜色。蓝色),
textAlign:textAlign.left,
),
onTap:()=>
this.setState(()=>this.bytes=Uint8List(0)),
),
),
文本(“|”,样式:TextStyle(字体大小:15,颜色:颜色
.black26(,
扩大(
弹性:5,
儿童:手势检测器(
onTap:()异步{
最终成功=等待ImageGallerySaver.saveImage(
import 'dart:async';
import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:image_gallery_saver/image_gallery_saver.dart';
import 'package:image_picker/image_picker.dart';
import 'package:qrscan/qrscan.dart' as scanner;
void main() {
runApp(MyApp());
}
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
Uint8List bytes = Uint8List(0);
TextEditingController _inputController;
TextEditingController _outputController;
@override
initState() {
super.initState();
this._inputController = new TextEditingController();
this._outputController = new TextEditingController();
}
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
backgroundColor: Colors.grey[300],
body: Builder(
builder: (BuildContext context) {
return ListView(
children: <Widget>[
_qrCodeWidget(this.bytes, context),
Container(
color: Colors.white,
child: Column(
children: <Widget>[
TextField(
controller: this._inputController,
keyboardType: TextInputType.url,
textInputAction: TextInputAction.go,
onSubmitted: (value) => _generateBarCode(value),
decoration: InputDecoration(
prefixIcon: Icon(Icons.text_fields),
helperText: 'Please input your code to generage qrcode image.',
hintText: 'Please Input Your Code',
hintStyle: TextStyle(fontSize: 15),
contentPadding: EdgeInsets.symmetric(
horizontal: 7, vertical: 15),
),
),
SizedBox(height: 20),
TextField(
controller: this._outputController,
maxLines: 2,
decoration: InputDecoration(
prefixIcon: Icon(Icons.wrap_text),
helperText: 'The barcode or qrcode you scan will be displayed in this area.',
hintText: 'The barcode or qrcode you scan will be displayed in this area.',
hintStyle: TextStyle(fontSize: 15),
contentPadding: EdgeInsets.symmetric(
horizontal: 7, vertical: 15),
),
),
SizedBox(height: 20),
this._buttonGroup(),
SizedBox(height: 70),
],
),
),
],
);
},
),
floatingActionButton: FloatingActionButton(
onPressed: () => _scanBytes(),
tooltip: 'Take a Photo',
child: const Icon(Icons.camera_alt),
),
),
);
}
Widget _qrCodeWidget(Uint8List bytes, BuildContext context) {
return Padding(
padding: EdgeInsets.all(20),
child: Card(
elevation: 6,
child: Column(
children: <Widget>[
Container(
child: Row(
crossAxisAlignment: CrossAxisAlignment.end,
children: <Widget>[
Icon(Icons.verified_user, size: 18, color: Colors.green),
Text(' Generate Qrcode', style: TextStyle(fontSize: 15)),
Spacer(),
Icon(Icons.more_vert, size: 18, color: Colors.black54),
],
),
padding: EdgeInsets.symmetric(horizontal: 10, vertical: 9),
decoration: BoxDecoration(
color: Colors.black12,
borderRadius: BorderRadius.only(
topLeft: Radius.circular(4), topRight: Radius.circular(4)),
),
),
Padding(
padding: EdgeInsets.only(
left: 40, right: 40, top: 30, bottom: 10),
child: Column(
children: <Widget>[
SizedBox(
height: 190,
child: bytes.isEmpty
? Center(
child: Text('Empty code ... ',
style: TextStyle(color: Colors.black38)),
)
: Image.memory(bytes),
),
Padding(
padding: EdgeInsets.only(top: 7, left: 25, right: 25),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: <Widget>[
Expanded(
flex: 5,
child: GestureDetector(
child: Text(
'remove',
style: TextStyle(
fontSize: 15, color: Colors.blue),
textAlign: TextAlign.left,
),
onTap: () =>
this.setState(() => this.bytes = Uint8List(0)),
),
),
Text('|', style: TextStyle(fontSize: 15, color: Colors
.black26)),
Expanded(
flex: 5,
child: GestureDetector(
onTap: () async {
final success = await ImageGallerySaver.saveImage(
this.bytes);
SnackBar snackBar;
if (success) {
snackBar = new SnackBar(content: new Text(
'Successful Preservation!'));
Scaffold.of(context).showSnackBar(snackBar);
} else {
snackBar =
new SnackBar(content: new Text('Save failed!'));
}
},
child: Text(
'save',
style: TextStyle(
fontSize: 15, color: Colors.blue),
textAlign: TextAlign.right,
),
),
),
],
),
)
],
),
),
Divider(height: 2, color: Colors.black26),
],
),
),
);
}
Widget _buttonGroup() {
return Row(
children: <Widget>[
Expanded(
flex: 1,
child: SizedBox(
height: 120,
child: InkWell(
onTap: () => _generateBarCode(this._inputController.text),
child: Card(
child: Column(
children: <Widget>[
Expanded(
flex: 2,
child: Image.asset('images/generate_qrcode.png'),
),
Divider(height: 20),
Expanded(flex: 1, child: Text("Generate")),
],
),
),
),
),
),
Expanded(
flex: 1,
child: SizedBox(
height: 120,
child: InkWell(
onTap: _scan,
child: Card(
child: Column(
children: <Widget>[
Expanded(
flex: 2,
child: Image.asset('images/scanner.png'),
),
Divider(height: 20),
Expanded(flex: 1, child: Text("Scan")),
],
),
),
),
),
),
Expanded(
flex: 1,
child: SizedBox(
height: 120,
child: InkWell(
onTap: _scanPhoto,
child: Card(
child: Column(
children: <Widget>[
Expanded(
flex: 2,
child: Image.asset('images/albums.png'),
),
Divider(height: 20),
Expanded(flex: 1, child: Text("Scan Photo")),
],
),
),
),
),
),
],
);
}
Future _scan() async {
String barcode = await scanner.scan();
if (barcode == null) {
print('nothing return.');
} else {
this._outputController.text = barcode;
}
}
Future _scanPhoto() async {
String barcode = await scanner.scanPhoto();
this._outputController.text = barcode;
}
Future _scanPath(String path) async {
String barcode = await scanner.scanPath(path);
this._outputController.text = barcode;
}
Future _scanBytes() async {
File file = await ImagePicker.pickImage(source: ImageSource.camera);
Uint8List bytes = file.readAsBytesSync();
String barcode = await scanner.scanBytes(bytes);
this._outputController.text = barcode;
}
Future _generateBarCode(String inputCode) async {
Uint8List result = await scanner.generateBarCode(inputCode);
this.setState(() => this.bytes = result);
}
}
class MyAppState extends State<MyApp> {
Future<SharedPreferences> _sPrefs = SharedPreferences.getInstance();
final TextEditingController controller = TextEditingController();
List<String> listOne, listTwo;
@override
void initState() {
super.initState();
listOne = [];
listTwo = [];
}
Future<Null> addString() async {
final SharedPreferences prefs = await _sPrefs;
listOne.add(controller.text);
prefs.setStringList('list', listOne);
setState(() {
controller.text = '';
});
}
Future<Null> clearItems() async {
final SharedPreferences prefs = await _sPrefs;
prefs.clear();
setState(() {
listOne = [];
listTwo = [];
});
}
Future<Null> getStrings() async {
final SharedPreferences prefs = await _sPrefs;
listTwo = prefs.getStringList('list');
setState(() {});
}
Future<Null> updateStrings(String str) async {
final SharedPreferences prefs = await _sPrefs;
setState(() {
listOne.remove(str);
listTwo.remove(str);
});
prefs.setStringList('list', listOne);
}
@override
Widget build(BuildContext context) {
getStrings();
return Center(
child: ListView(
children: <Widget>[
TextField(
controller: controller,
decoration: InputDecoration(
hintText: 'Type in something...',
)),
RaisedButton(
child: Text("Submit"),
onPressed: () {
addString();
},
),
RaisedButton(
child: Text("Clear"),
onPressed: () {
clearItems();
},
),
Flex(
direction: Axis.vertical,
children: listTwo == null
? []
: listTwo
.map((String s) => Dismissible(
key: Key(s),
onDismissed: (direction) {
updateStrings(s);
},
child: ListTile(
title: Text(s),
)))
.toList(),
)
],
),
);
}
}
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.dark().copyWith(scaffoldBackgroundColor: darkBlue),
debugShowCheckedModeBanner: false,
//Here I have called MyWidget Class
home: MyWidget()
);
}
}
class MyWidget extends StatefulWidget {
@override
_MyWidgetState createState() => _MyWidgetState();
}
class _MyWidgetState extends State<MyWidget> {
Uint8List bytes = Uint8List(0);
TextEditingController _inputController;
TextEditingController _outputController;
@override
initState() {
super.initState();
this._inputController = new TextEditingController();
this._outputController = new TextEditingController();
}
@override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(