Develop Reference

How to close the SimpleDialog in flutter after choosing an option - android

I added a SimpleDialog with 2 options: lost and found. Whenever I make my selection and get redirected to where I want, the SimpleDialog doesn't close and stays on my screen.
The switch:
switch (
await showDialog(
context: context,
child: new SimpleDialog(
title: new Text("Which category?"),
children: <Widget>[
new SimpleDialogOption(child: new Text("Found"),
onPressed: () {
goToCreate();
},
),
new SimpleDialogOption(child: new Text("Lost"),
onPressed: () {
//Whatever
},
),
],
)
)
)
And the cases:
{
case "Found":
goToCreate();
break;
case "Lost":
//Whatever
break;
}

You can do this from the dialog when you press Accept (or whatever):
Navigator.pop(context, true); // You could return any Dart type, like an enum
From the caller:
bool dialogReturnValue = await showDialog(...);
if (dialogReturnValue == true){
// do something
}

From official docs: https://docs.flutter.io/flutter/material/SimpleDialog-class.html
You need to execute inside options' onPressed method this:
Navigator.pop(context, ===arguments===);
Full example:
SimpleDialog(
title: const Text('Select assignment'),
children: <Widget>[
SimpleDialogOption(
onPressed: () { Navigator.pop(context, Department.treasury); },
child: const Text('Treasury department'),
),
SimpleDialogOption(
onPressed: () { Navigator.pop(context, Department.state); },
child: const Text('State department'),
),
],
);
EDIT:
switch (
await showDialog(
context: context,
child: new SimpleDialog(
title: new Text("Which category?"),
children: <Widget>[
new SimpleDialogOption(child: new Text("Found"),
onPressed: () {
Navigator.pop(context, 'Found'); //Close the SimpleDialog then=>
goToCreate();
},
),
new SimpleDialogOption(child: new Text("Lost"),
onPressed: () {
Navigator.pop(context, 'Lost'); //For closing the SimpleDialog
//After that do whatever you want
},
),
],
)
)
)
)
EDIT 2 (Demo Application):
import 'package:flutter/material.dart';
void main() {
runApp(App());
}
class App extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Test(),
);
}
}
class Test extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(onPressed: () {
_askedToLead(context);
}),
),
);
}
Future<void> _askedToLead(BuildContext context) async {
switch (await showDialog<String>(
context: context,
builder: (BuildContext context) {
return SimpleDialog(
title: const Text('Select assignment'),
children: <Widget>[
SimpleDialogOption(
onPressed: () {
Navigator.pop(context, 'Found');
},
child: const Text('FOUND'),
),
SimpleDialogOption(
onPressed: () {
Navigator.pop(context, 'Lost');
},
child: const Text('LOST'),
),
],
);
})) {
case 'Found':
print('FOUND!');
break;
case 'Lost':
print('LOST!');
break;
}
}
}

Related

Frontend looks of read and write command.
I need to change the design of read and write command on the bluetooth devcie screen.
I used the code from pauldemarco git repository.
But the device screen frontend design does not suit good for my application.
Can anyone share how to change the design of upload and download signal button on the user interface?
import 'dart:async';
import 'dart:math';
import 'package:flutter/material.dart';
import 'package:flutter_blue/flutter_blue.dart';
import 'widgets.dart';
import 'dart:ui' as ui;
import 'package:flutter/rendering.dart';
import 'package:dproject/qrcode.dart';
void main() {
// RenderErrorBox.backgroundColor = Colors.transparent;
ErrorWidget.builder = (FlutterErrorDetails details) => Scaffold(body:Center(child: Text("Click the Refresh Button"),));
runApp(FlutterBlueApp());
// static ErrorWidgetBuilder builder = _defaultErrorWidgetBuilder;
// RenderErrorBox.textStyle = ui.TextStyle(color: Colors.transparent);
}
class FlutterBlueApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
color: Colors.lightBlue,
home: StreamBuilder<BluetoothState>(
stream: FlutterBlue.instance.state,
initialData: BluetoothState.unknown,
builder: (c, snapshot) {
final state = snapshot.data;
if (state == BluetoothState.on) {
return FindDevicesScreen();
}
return BluetoothOffScreen(state: state);
}),
);
}
}
class BluetoothOffScreen extends StatelessWidget {
const BluetoothOffScreen({Key? key, this.state}) : super(key: key);
final BluetoothState? state;
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.lightBlue,
body: Center(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Icon(
Icons.bluetooth_disabled,
size: 200.0,
color: Colors.white54,
),
Text(
'Bluetooth Adapter is ${state != null ? state.toString().substring(15) : 'not available'}.',
// style: Theme.of(context)
// .primaryTextTheme
// .subhead
// ?.copyWith(color: Colors.white),
),
],
),
),
);
}
}
class FindDevicesScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Find Devices'),
),
body: RefreshIndicator(
onRefresh: () =>
FlutterBlue.instance.startScan(timeout: Duration(seconds: 8)),
child: SingleChildScrollView(
child: Column(
children: <Widget>[
StreamBuilder<List<BluetoothDevice>>(
stream: Stream.periodic(Duration(seconds: 2))
.asyncMap((_) => FlutterBlue.instance.connectedDevices),
initialData: [],
builder: (c, snapshot) => Column(
children: snapshot.data!
.map((d) => ListTile(
// title: Text(d.toString()),
// subtitle: Text(d.id.toString()),
trailing: StreamBuilder<BluetoothDeviceState>(
stream: d.state,
initialData: BluetoothDeviceState.disconnected,
builder: (c, snapshot) {
if (snapshot.data ==
BluetoothDeviceState.connected) {
return ElevatedButton(
child: Text('OPEN'),
onPressed: () => Navigator.of(context).push(
MaterialPageRoute(
builder: (context) =>
DeviceScreen(device: d))),
);
}
return Text(snapshot.data.toString());
},
),
))
.toList(),
),
),
StreamBuilder<List<ScanResult>>(
stream: FlutterBlue.instance.scanResults,
initialData: [],
builder: (c, snapshot){
List<ScanResult> data = [];
// print("sh");
for(int i=0;i<snapshot.data!.length;i++)
{
// print("sh");
// print(snapshot.data![i]);
if(snapshot.data![i].device.id.toString()=='FC:67:78:5D:96:EF'){
data.add(snapshot.data![i]);
}
}
// print(data);
return Column(
children: data
.map(
(r) => ScanResultTile(
result: r,
onTap: () => Navigator.of(context)
.push(MaterialPageRoute(builder: (context) {
r.device.connect();
return DeviceScreen(device: r.device); //FlutterBlueApp();
})),
),
)
.toList(),
);
},
),
],
),
),
),
floatingActionButton: StreamBuilder<bool>(
stream: FlutterBlue.instance.isScanning,
initialData: false,
builder: (c, snapshot) {
if (snapshot.data!) {
return FloatingActionButton(
child: Icon(Icons.stop),
onPressed: () => FlutterBlue.instance.stopScan(),
backgroundColor: Colors.red,
);
} else {
return FloatingActionButton(
child: Icon(Icons.search),
onPressed: () => FlutterBlue.instance
.startScan(timeout: Duration(seconds: 8)));
}
},
),
);
}
}
class DeviceScreen extends StatelessWidget {
const DeviceScreen({Key? key, required this.device}) : super(key: key);
final BluetoothDevice device;
List<int> _getRandomBytes() {
final math = Random();
return [
math.nextInt(255),
math.nextInt(255),
math.nextInt(255),
math.nextInt(255)
];
}
List<Widget> _buildServiceTiles(List<BluetoothService> services) {
List<BluetoothService> data = [];
print("sh%%%%%%%%%%%%%%%%%%%%%%####");
for(int i=0;i<services.length;i++)
{
print("sh####################################");
// print(services[i]);
if(i==2){
data.add(services[i]);
}
}
// print(data);
return data //services
.map(
(s) => ServiceTile(
service: s,
characteristicTiles: s.characteristics
.map(
(c) => CharacteristicTile(
characteristic: c,
onReadPressed: () {
c.read();
},
onWritePressed: () async {
await c.write([1], withoutResponse: false);
await c.read();
// ElevatedButton(
// // style: style,
// onPressed: null,
// child: const Text('Disabled'),
// );
},
onNotificationPressed: () async {
await c.setNotifyValue(!c.isNotifying);
await c.read();
},
descriptorTiles: c.descriptors
.map(
(d) => DescriptorTile(
descriptor: d,
onReadPressed: () => d.read(),
onWritePressed: () => d.write([1]),
),
)
.toList(),
),
)
.toList(),
),
)
.toList();
// print(c.read);
}
// #override
// State<DeviceScreen> createState() => _DeviceScreenState();
// }
// class _DeviceScreenState extends State<DeviceScreen> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("BITLOCK"),//device.name
actions: <Widget>[
StreamBuilder<BluetoothDeviceState>(
stream: device.state,
initialData: BluetoothDeviceState.connecting,
builder: (c, snapshot) {
VoidCallback? onPressed;
String text;
switch (snapshot.data) {
case BluetoothDeviceState.connected:
onPressed = () => device.disconnect();
text = 'DISCONNECT';
break;
case BluetoothDeviceState.disconnected:
onPressed = () => device.connect();
text = 'CONNECT';
break;
default:
onPressed = null;
text = snapshot.data.toString().substring(21).toUpperCase();
break;
}
return TextButton(
onPressed: onPressed,
child: Text(
text,
style: Theme.of(context)
.primaryTextTheme
.button
?.copyWith(color: Colors.white),
));
},
)
],
),
body: SingleChildScrollView(
child: Column(
children: <Widget>[
StreamBuilder<BluetoothDeviceState>(
stream: device.state,
initialData: BluetoothDeviceState.connecting,
builder: (c, snapshot) => ListTile(
leading: (snapshot.data == BluetoothDeviceState.connected)
? Icon(Icons.bluetooth_connected)
: Icon(Icons.bluetooth_disabled),
title: Text(((){
if(snapshot.data.toString().split('.')[1]=="connected"){
return 'Your Lock is ${snapshot.data.toString().split('.')[1]} to your device.';
}
return 'Your Lock is ${snapshot.data.toString().split('.')[1]} from your device.';
})()),
// subtitle: Text('${device.id}'),
trailing: StreamBuilder<bool>(
stream: device.isDiscoveringServices,
initialData: false,
builder: (c, snapshot) => IndexedStack(
index: snapshot.data! ? 1 : 0,
children: <Widget>[
IconButton(
icon: Icon(Icons.refresh),
onPressed: () => device.discoverServices(),
),
IconButton(
icon: SizedBox(
child: CircularProgressIndicator(
valueColor: AlwaysStoppedAnimation(Colors.grey),
),
width: 18.0,
height: 18.0,
),
onPressed: null,
)
],
),
),
),
),
StreamBuilder<int>(
stream: device.mtu,
initialData: 0,
builder: (c, snapshot) => ListTile(
// title: Text('MTU Size'),
// subtitle: Text('${snapshot.data} bytes'),
trailing: IconButton(
icon: Icon(Icons.lock_open),
onPressed: () => device.requestMtu(223),
),
),
),
StreamBuilder<List<BluetoothService>>(
stream: device.services,
initialData: [],
builder: (c, snapshot) {
return Column(
children: _buildServiceTiles(snapshot.data!),
);
},
),
],
),
),
);
}
}
Thanks in advance.

Here is the solution I found.
You will find widgets.dart in the lib folder in which you are working with main.dart and other files.
You can edit this file according to required design.
In my case, I need to change Iconbutton icon in characteristics tile to change the design of read and write button.

I'm trying to make a webview app for my website and use the following starter code
import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Welcome to Flutter1',
home: Scaffold(
appBar: AppBar(
title: const Text('Welcome to Flutter1'),
),
body: WebView(
initialUrl: "URL.com",
javascriptMode: JavascriptMode.unrestricted,
),
),
);
}
}
PROBLEM
While the app opens the page, the navigation menu (three dots) do not respond when I click.
What can I do?
EDIT
I also tried to allow all mixed content using flutter_inappwebview
import 'package:flutter/material.dart';
import 'package:flutter_inappwebview/flutter_inappwebview.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Welcome to Flutter2',
home: Scaffold(
appBar: AppBar(
title: const Text('Welcome to Flutter2'),
),
body: InAppWebView(
initialUrlRequest: URLRequest(url: Uri.parse("www.URL.com")),
initialOptions: InAppWebViewGroupOptions(
android: AndroidInAppWebViewOptions(
mixedContentMode: AndroidMixedContentMode.MIXED_CONTENT_COMPATIBILITY_MODE
)
),
),
),
);
}
}
Still the dots are not working.

you have to have a controller for your Navigation- and WebView-Menu
final Completer<WebViewController> _controller =
Completer<WebViewController>();
then in your build methode:
Scaffold(
appBar: AppBar(
title: Text('Webview'),
actions: <Widget>[
NavigationControls(_controller.future),
WebViewMenu(_controller.future),
],
}
),
body: Builder(....)...
these are the classes from https://pub.dev/packages/webview_flutter/example
class WebViewMenu extends StatelessWidget {
WebViewMenu(this.controller);
final Future<WebViewController> controller;
final CookieManager cookieManager = CookieManager();
#override
Widget build(BuildContext context) {
return FutureBuilder<WebViewController>(
future: controller,
builder:
(BuildContext context, AsyncSnapshot<WebViewController> controller) {
if (controller.hasError) {
return Text('Controller has Error');
}
return PopupMenuButton<MenuOptions>(
onSelected: (MenuOptions value) {
switch (value) {
case MenuOptions.showUserAgent:
_onShowUserAgent(controller.data!, context);
break;
case MenuOptions.listCookies:
_onListCookies(controller.data!, context);
break;
case MenuOptions.clearCookies:
_onClearCookies(context);
break;
case MenuOptions.addToCache:
_onAddToCache(controller.data!, context);
break;
case MenuOptions.listCache:
_onListCache(controller.data!, context);
break;
case MenuOptions.clearCache:
_onClearCache(controller.data!, context);
break;
case MenuOptions.navigationDelegate:
_onNavigationDelegateExample(controller.data!, context);
break;
}
},
itemBuilder: (BuildContext context) => <PopupMenuItem<MenuOptions>>[
PopupMenuItem<MenuOptions>(
value: MenuOptions.showUserAgent,
child: const Text('Show user agent'),
enabled: controller.hasData,
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.listCookies,
child: Text('List cookies'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.clearCookies,
child: Text('Clear cookies'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.addToCache,
child: Text('Add to cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.listCache,
child: Text('List cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.clearCache,
child: Text('Clear cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.navigationDelegate,
child: Text('Navigation Delegate example'),
),
],
);
},
);
}
void _onShowUserAgent(
WebViewController controller, BuildContext context) async {
// Send a message with the user agent string to the Toaster JavaScript channel we registered
// with the WebView.
await controller.evaluateJavascript(
'Toaster.postMessage("User Agent: " + navigator.userAgent);');
}
void _onListCookies(
WebViewController controller, BuildContext context) async {
final String cookies =
await controller.evaluateJavascript('document.cookie');
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(SnackBar(
content: Column(
mainAxisAlignment: MainAxisAlignment.end,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
const Text('Cookies:'),
_getCookieList(cookies),
],
),
));
}
void _onAddToCache(WebViewController controller, BuildContext context) async {
await controller.evaluateJavascript(
'caches.open("test_caches_entry"); localStorage["test_localStorage"] = "dummy_entry";');
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(const SnackBar(
content: Text('Added a test entry to cache.'),
));
}
void _onListCache(WebViewController controller, BuildContext context) async {
await controller.evaluateJavascript('caches.keys()'
'.then((cacheKeys) => JSON.stringify({"cacheKeys" : cacheKeys, "localStorage" : localStorage}))'
'.then((caches) => Toaster.postMessage(caches))');
}
void _onClearCache(WebViewController controller, BuildContext context) async {
await controller.clearCache();
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(const SnackBar(
content: Text("Cache cleared."),
));
}
void _onClearCookies(BuildContext context) async {
final bool hadCookies = await cookieManager.clearCookies();
String message = 'There were cookies. Now, they are gone!';
if (!hadCookies) {
message = 'There are no cookies.';
}
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(SnackBar(
content: Text(message),
));
}
void _onNavigationDelegateExample(
WebViewController controller, BuildContext context) async {
final String contentBase64 =
base64Encode(const Utf8Encoder().convert(kNavigationExamplePage));
await controller.loadUrl('data:text/html;base64,$contentBase64');
}
Widget _getCookieList(String cookies) {
if (cookies == null || cookies == '""') {
return Container();
}
final List<String> cookieList = cookies.split(';');
final Iterable<Text> cookieWidgets =
cookieList.map((String cookie) => Text(cookie));
return Column(
mainAxisAlignment: MainAxisAlignment.end,
mainAxisSize: MainAxisSize.min,
children: cookieWidgets.toList(),
);
}
}
class NavigationControls extends StatelessWidget {
const NavigationControls(this._webViewControllerFuture);
final Future<WebViewController> _webViewControllerFuture;
#override
Widget build(BuildContext context) {
return FutureBuilder<WebViewController>(
future: _webViewControllerFuture,
builder:
(BuildContext context, AsyncSnapshot<WebViewController> snapshot) {
if (snapshot.hasError) {
return Text(snapshot.error.toString());
}
if (snapshot.hasData) {
final bool webViewReady =
snapshot.connectionState == ConnectionState.done;
final WebViewController controller = snapshot.data!;
return Row(
children: <Widget>[
IconButton(
icon: const Icon(Icons.arrow_back_ios),
onPressed: !webViewReady
? null
: () async {
if (await controller.canGoBack()) {
await controller.goBack();
} else {
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(
const SnackBar(
content: Text("No back history item")),
);
return;
}
},
),
IconButton(
icon: const Icon(Icons.arrow_forward_ios),
onPressed: !webViewReady
? null
: () async {
if (await controller.canGoForward()) {
await controller.goForward();
} else {
// ignore: deprecated_member_use
Scaffold.of(context).showSnackBar(
const SnackBar(
content: Text("No forward history item")),
);
return;
}
},
),
IconButton(
icon: const Icon(Icons.replay),
onPressed: !webViewReady
? null
: () {
controller.reload();
},
),
],
);
}
return Text('loading navigationControls');
},
);
}
}

I am currently running into an issue with my ble project for flutter. I am using the flutter blue package by Paul DeMarco and the additional page for the app is based on "ThatProject" dust sensor from youtube. I have an Adafruit Feather 32u4 board, and I am attempting to notify the client (my flutter app) that It has a series of numbers to send, but I am not getting any output. I am able to connect to the device, and seem to properly send the service UUID and characteristic UUID, but im not sure if it is coming with proper properties.
I am using the adafruit BLE code to program the board, and I can get the values if I use adafruit's app. I am just trying to get the values on my own flutter app.
I am running into an error as follows:
E/flutter (32139): [ERROR:flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: PlatformException(set_notification_error, could not locate CCCD descriptor for characteristic: 6e400002-b5a3-f393-e0a9-e50e24dcca9e, null, null)
Here is my code. I believe the missing CCCD is coming from this part:
import 'dart:async';
import 'dart:convert' show utf8;
import 'package:flutter/material.dart';
import 'package:flutter_blue/flutter_blue.dart';
import 'package:oscilloscope/oscilloscope.dart';
class SensorPage extends StatefulWidget {
const SensorPage({Key key, this.device}) : super(key: key);
final BluetoothDevice device;
#override
_SensorPageState createState() => _SensorPageState();
}
class _SensorPageState extends State<SensorPage> {
final String SERVICE_UUID = "6e400001-b5a3-f393-e0a9-e50e24dcca9e";
final String CHARACTERISTIC_UUID = "6e400002-b5a3-f393-e0a9-e50e24dcca9e";
bool isReady;
Stream<List<int>> stream;
List<double> traceDust = List();
#override
void initState() {
super.initState();
isReady = false;
connectToDevice();
}
connectToDevice() async {
// if (widget.device == null) {
// // _Pop();
// return;
// }
//timeout timer, watchdog timer if you will
new Timer(const Duration(seconds: 15), () {
if (!isReady) {
disconnectFromDevice();
// _Pop();
}
});
await widget.device.connect();
discoverServices();
}
disconnectFromDevice() {
if (widget.device == null) {
//_Pop();
return;
}
widget.device.disconnect();
}
discoverServices() async {
// if (widget.device == null) {
// // _Pop();
// return;
// }
BluetoothCharacteristic ss;
List<BluetoothService> services = await widget.device.discoverServices();
services.forEach((service) {
debugPrint("This Service UUID is!${service.uuid.toString()}");
if (service.uuid.toString() == SERVICE_UUID) {
service.characteristics.forEach((characteristic) {
debugPrint("This char UUID is!${characteristic.uuid.toString()}");
if (characteristic.uuid.toString() == CHARACTERISTIC_UUID) {
debugPrint("Here is !isNotifying: ${!characteristic.isNotifying}");
debugPrint("Here is characteristic.value: ${characteristic.value}");
ss = characteristic;
stream = ss.value;
setState(() {
isReady = true;
});
} //this one
});
} //this one
});
await ss.setNotifyValue(true);
stream = ss.value;
if (!isReady) {
// _Pop();
}
}
Future<bool> _onWillPop() {
return showDialog(
context: context,
builder: (context) =>
new AlertDialog(
title: Text('Are you sure?'),
content: Text('Do you want to disconnect device and go back?'),
actions: <Widget>[
new FlatButton(
onPressed: () => Navigator.of(context).pop(false),
child: new Text('No')),
new FlatButton(
onPressed: () {
disconnectFromDevice();
Navigator.of(context).pop(true);
},
child: new Text('Yes')),
],
) ??
false);
}
// _Pop() {
// Navigator.of(context).pop(true);
// }
String _dataParser(List<int> dataFromDevice) {
debugPrint("current value is-> ${utf8.decode(dataFromDevice)}");
return utf8.decode(dataFromDevice);
}
#override
Widget build(BuildContext context) {
Oscilloscope oscilloscope = Oscilloscope(
showYAxis: true,
padding: 0.0,
backgroundColor: Colors.black,
traceColor: Colors.white,
yAxisMax: 3000.0,
yAxisMin: 0.0,
dataSet: traceDust,
);
return WillPopScope(
onWillPop: _onWillPop,
child: Scaffold(
appBar: AppBar(
title: Text('Optical Dust Sensor'),
),
body: Container(
child: !isReady
? Center(
child: Text(
"Waiting...",
style: TextStyle(fontSize: 24, color: Colors.red),
),
)
: Container(
child: StreamBuilder<List<int>>(
stream: stream,
builder: (BuildContext context,
AsyncSnapshot<List<int>> snapshot) {
if (snapshot.hasError)
return Text('Error: ${snapshot.error}');
if (snapshot.connectionState ==
ConnectionState.active) {
debugPrint("snapshot.error: ${snapshot.error}.");
debugPrint("snapshot.data: ${snapshot.error}.");
debugPrint(
"snapshot.connectionState: ${snapshot.connectionState}.");
debugPrint("snapshot.hasdata?: ${snapshot.hasData}.");
var currentValue = _dataParser(snapshot.data);
traceDust.add(double.tryParse(currentValue) ?? 0);
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Expanded(
flex: 1,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text('Current value from Sensor',
style: TextStyle(fontSize: 14)),
Text('$currentValue ug/m3',
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 24))
]),
),
Expanded(
flex: 1,
child: oscilloscope,
)
],
));
} else {
return Text('Check the stream');
}
},
),
)),
),
);
}
}
// Copyright 2017, Paul DeMarco.
// 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 'package:flutter/material.dart';
import 'package:K9Harness/Pages/Sensor_page.dart';
import 'package:K9Harness/Bluetooth/widgets.dart';
import 'package:flutter_blue/flutter_blue.dart';
class MyBluetoothPage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
color: Colors.lightBlue,
home: StreamBuilder<BluetoothState>(
stream: FlutterBlue.instance.state,
initialData: BluetoothState.unknown,
builder: (c, snapshot) {
final state = snapshot.data;
if (state == BluetoothState.on) {
return FindDevicesScreen();
}
return BluetoothOffScreen(state: state);
}),
);
}
}
class BluetoothOffScreen extends StatelessWidget {
const BluetoothOffScreen({Key key, this.state}) : super(key: key);
final BluetoothState state;
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.lightBlue,
body: Center(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Icon(
Icons.bluetooth_disabled,
size: 200.0,
color: Colors.white54,
),
Text(
'Bluetooth Adapter is ${state.toString().substring(15)}.',
style: Theme.of(context)
.primaryTextTheme
.subhead
.copyWith(color: Colors.white),
),
],
),
),
);
}
}
class FindDevicesScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Find Devices'),
),
body: RefreshIndicator(
onRefresh: () => FlutterBlue.instance
.startScan(
scanMode: ScanMode.balanced,
withServices: [
Guid("6E400001-B5A3-F393-E0A9-E50E24DCCA9E")
], //FIXME check the other ways where ".startScan" is implemented
timeout: Duration(seconds: 4))
.catchError((error) {
print("error starting scan $error");
}),
child: SingleChildScrollView(
child: Column(
children: <Widget>[
StreamBuilder<List<BluetoothDevice>>(
stream: Stream.periodic(Duration(seconds: 2))
.asyncMap((_) => FlutterBlue.instance.connectedDevices),
initialData: [],
builder: (c, snapshot) => Column(
children: snapshot.data
.map((d) => ListTile(
title: Text(d.name),
subtitle: Text(d.id.toString()),
trailing: StreamBuilder<BluetoothDeviceState>(
stream: d.state,
initialData: BluetoothDeviceState.disconnected,
builder: (c, snapshot) {
if (snapshot.data ==
BluetoothDeviceState.connected) {
return RaisedButton(
child: Text('OPEN'),
onPressed: () => Navigator.of(context).push(
MaterialPageRoute(
builder: (context) =>
DeviceScreen(device: d))),
);
}
return Text(snapshot.data.toString());
},
),
))
.toList(),
),
),
StreamBuilder<List<ScanResult>>(
stream: FlutterBlue.instance.scanResults,
initialData: [],
builder: (c, snapshot) => Column(
children: snapshot.data
.map(
(r) => ScanResultTile(
result: r,
onTap: () => Navigator.of(context)
.push(MaterialPageRoute(builder: (context) {
r.device.connect();
return SensorPage(device: r.device);
})),
),
)
.toList(),
),
),
],
),
),
),
floatingActionButton: StreamBuilder<bool>(
stream: FlutterBlue.instance.isScanning,
initialData: false,
builder: (c, snapshot) {
if (snapshot.data) {
return FloatingActionButton(
child: Icon(Icons.stop),
onPressed: () => FlutterBlue.instance.stopScan(),
backgroundColor: Colors.red,
);
} else {
return FloatingActionButton(
child: Icon(Icons.search),
onPressed: () => FlutterBlue.instance
.startScan(
scanMode: ScanMode.balanced,
withServices: [
Guid("6E400001-B5A3-F393-E0A9-E50E24DCCA9E")
], //FIXME check the other ways where ".startScan" is implemented
timeout: Duration(seconds: 4))
.catchError((error) {
print("error starting scan $error");
}));
}
},
),
);
}
}
class DeviceScreen extends StatelessWidget {
const DeviceScreen({Key key, this.device}) : super(key: key);
final BluetoothDevice device;
List<Widget> _buildServiceTiles(List<BluetoothService> services) {
return services
.map(
(s) => ServiceTile(
service: s,
characteristicTiles: s.characteristics
.map(
(c) => CharacteristicTile(
characteristic: c,
onReadPressed: () => c.read(),
onWritePressed: () => c.write([13, 24]),
onNotificationPressed: () =>
c.setNotifyValue(!c.isNotifying),
descriptorTiles: c.descriptors
.map(
(d) => DescriptorTile(
descriptor: d,
onReadPressed: () => d.read(),
onWritePressed: () => d.write([11, 12]),
),
)
.toList(),
),
)
.toList(),
),
)
.toList();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(device.name),
actions: <Widget>[
StreamBuilder<BluetoothDeviceState>(
stream: device.state,
initialData: BluetoothDeviceState.connecting,
builder: (c, snapshot) {
VoidCallback onPressed;
String text;
switch (snapshot.data) {
case BluetoothDeviceState.connected:
onPressed = () => device.disconnect();
text = 'DISCONNECT';
break;
case BluetoothDeviceState.disconnected:
onPressed = () => device.connect();
text = 'CONNECT';
break;
default:
onPressed = null;
text = snapshot.data.toString().substring(21).toUpperCase();
break;
}
return FlatButton(
onPressed: onPressed,
child: Text(
text,
style: Theme.of(context)
.primaryTextTheme
.button
.copyWith(color: Colors.white),
));
},
)
],
),
body: SingleChildScrollView(
child: Column(
children: <Widget>[
StreamBuilder<BluetoothDeviceState>(
stream: device.state,
initialData: BluetoothDeviceState.connecting,
builder: (c, snapshot) => ListTile(
leading: (snapshot.data == BluetoothDeviceState.connected)
? Icon(Icons.bluetooth_connected)
: Icon(Icons.bluetooth_disabled),
title: Text(
'Device is ${snapshot.data.toString().split('.')[1]}.'),
subtitle: Text('${device.id}'),
trailing: StreamBuilder<bool>(
stream: device.isDiscoveringServices,
initialData: false,
builder: (c, snapshot) => IndexedStack(
index: snapshot.data ? 1 : 0,
children: <Widget>[
IconButton(
icon: Icon(Icons.refresh),
onPressed: () => device.discoverServices(),
),
IconButton(
icon: SizedBox(
child: CircularProgressIndicator(
valueColor: AlwaysStoppedAnimation(Colors.grey),
),
width: 18.0,
height: 18.0,
),
onPressed: null,
)
],
),
),
),
),
StreamBuilder<int>(
stream: device.mtu,
initialData: 0,
builder: (c, snapshot) => ListTile(
title: Text('MTU Size'),
subtitle: Text('${snapshot.data} bytes'),
trailing: IconButton(
icon: Icon(Icons.edit),
onPressed: () => device.requestMtu(223),
),
),
),
StreamBuilder<List<BluetoothService>>(
stream: device.services,
initialData: [],
builder: (c, snapshot) {
return Column(
children: _buildServiceTiles(snapshot.data),
);
},
),
],
),
),
);
}
}

I figured it out, I had my characteristic UUID to be 6e400002-b5a3-f393-e0a9-e50e24dcca9e and it should have been 6e400003-b5a3-f393-e0a9-e50e24dcca9e because for the feather, the notification/notify characteristic is mandatory to be 0x0003 instead of the 2. It then passed the CCCD properly when I changed this value.

I have an app with three different pages. To navigate between the pages I use a bottom navigation. One of the pages contains a form. Before leaving the form page, I want to display a confirmation dialog. I know that I can intercept the back button of the device with WillPopScope. This works perfectly. But WillPopScope is not triggered when I leave the page via the bottom navigation.
I have also tried using the WidgetsBindingObserver, but both didPopRoute and didPushRoute are never triggered.
Any ideas what I can do?
My form page:
class TodayTimeRecordFormState extends State<TodayTimeRecordForm> with WidgetsBindingObserver{
final formKey = GlobalKey<FormState>();
TodayTimeRecordFormState();
#override
void initState() {
super.initState();
WidgetsBinding.instance.addObserver(this);
}
#override
void dispose() {
WidgetsBinding.instance.removeObserver(this);
super.dispose();
}
#override
Future<bool> didPopRoute() {
//never called
_onWillPop();
}
#override
Future<bool> didPushRoute(String route){
//never called
_onWillPop();
}
#override
Widget build(BuildContext context) {
return WillPopScope(
// called when the device back button is pressed.
onWillPop: _onWillPop,
child: Scaffold(...));
}
Future<bool> _onWillPop() {
return showDialog(
context: context,
child: new AlertDialog(
title: new Text('Are you sure?'),
content: new Text('Unsaved data will be lost.'),
actions: <Widget>[
new FlatButton(
onPressed: () => Navigator.of(context).pop(false),
child: new Text('No'),
),
new FlatButton(
onPressed: () => Navigator.of(context).pop(true),
child: new Text('Yes'),
),
],
),
);
}
}
Page containing the bottom navigation:
const List<Navigation> allNavigationItems = <Navigation>[
Navigation('Form', Icons.home, Colors.orange),
Navigation('Page2', Icons.work_off, Colors.orange),
Navigation('Page3', Icons.poll, Colors.orange)
];
class HomePage extends StatefulWidget {
#override
State<StatefulWidget> createState() {
return HomePageState();
}
}
class HomePageState extends State<HomePage> {
int selectedTab = 0;
final pageOptions = [
TodayTimeRecordForm(),
Page2(),
Page3(),
),
];
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(AppConfig.instance.values.title),
),
body: pageOptions[selectedTab],
bottomNavigationBar: BottomNavigationBar(
currentIndex: selectedTab,
unselectedItemColor: Colors.grey,
showUnselectedLabels: true,
selectedItemColor: Colors.amber[800],
onTap: (int index) {
setState(() {
selectedTab = index;
});
},
items: allNavigationItems.map((Navigation navigationItem) {
return BottomNavigationBarItem(
icon: Icon(navigationItem.icon),
backgroundColor: Colors.white,
label: navigationItem.title);
}).toList(),
),
);
}
}

You can do it by modifying your BottomNavigationBar's onTap.
onTap: (int index) {
if (selectedTab == 0 && index != 0){
// If the current tab is the first tab (the form tab)
showDialog(
context: context,
child: new AlertDialog(
title: new Text('Are you sure?'),
content: new Text('Unsaved data will be lost.'),
actions: <Widget>[
new FlatButton(
onPressed: () => Navigator.pop(context), // Closes the dialog
child: new Text('No'),
),
new FlatButton(
onPressed: () {
setState(()=>selectedTab = index); // Changes the tab
Navigator.pop(context); // Closes the dialog
},
child: new Text('Yes'),
),
],
),
);
} else {
// If the current tab isn't the form tab
setState(()=>selectedTab = index);
}
},

I have 4 bottomNavigationBar that each one has a webview.
but when tap in a one bottomNavigationBar and select a section in webview page, I can't back to previous page in webview by button back device.
I want back in webview just by back button device.
it is now when the press back button exit the app.
but I use double_back_to_close_app.dart to exit the app.
the home class :
import 'package:webview_flutter/webview_flutter.dart';
import 'package:fancy_bar/fancy_bar.dart';
import 'placeholder_widget.dart';
class Home extends StatefulWidget {
#override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
int _currentIndex = 0;
final List<Widget> _children = [
MyPlaceholderWidget('https://googel.com'),
MyPlaceholderWidget('https://googel.com'),
MyPlaceholderWidget('https://googel.com'),
MyPlaceholderWidget('https://googel.com')
];
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: PreferredSize(
preferredSize: Size.fromHeight(40.0),
child: AppBar(
automaticallyImplyLeading: false,
backgroundColor: Colors.grey[200],
elevation: 0.0,
)
),
body: DoubleBackToCloseApp(
child: _children[_currentIndex],
snackBar: const SnackBar(
content: Text(
'برای خروج دو بار کلیک کنید',
style: TextStyle(fontFamily: "Shabnam"),
textDirection: TextDirection.rtl,
textAlign: TextAlign.center,
),
),
),
bottomNavigationBar: FancyBottomBar(
onItemSelected: onTabTapped,
selectedIndex: _currentIndex, // this will be set when a new tab is tapped
items: [
FancyItem(
textColor: Colors.green,
title: 'حساب',
icon: Icon(
LineIcons.user,
size: 29,
),
),
FancyItem(
textColor: Colors.green,
title: 'وبلاگ',
icon: Icon(
LineIcons.file_text,
size: 27,
),
),
FancyItem(
textColor: Colors.green,
title: 'سبد خرید',
icon: Icon(
LineIcons.shopping_cart,
size: 31,
),
),
FancyItem(
textColor: Colors.green,
title: 'صفحه اصلی',
icon: Icon(
LineIcons.home,
size: 28,
),
),
],
),
);
}
void onTabTapped(int index) {
setState(() {
_currentIndex = index;
});
}
}
and the webview class in placeholder_widget.dart:
WebViewController controller;
class MyPlaceholderWidget extends StatelessWidget {
var url = 'https://www.mayehtaj.ir' ;
final key = UniqueKey();
MyPlaceholderWidget(String url){
this.url = url ;
}
#override
Widget build(BuildContext context) {
return WebView(
key: key,
javascriptMode: JavascriptMode.unrestricted,
initialUrl: url,
onWebViewCreated: (WebViewController webViewController){
controller = webViewController;
});
}
}
How to detect press back button device and go back to previous page in one webview ?
thank you for help !

You can copy paste run full code below
You can wrap Scaffold with WillPopScope
When user click device back button, you can execute WebView Controller goback
code snippet onwillpop
#override
Widget build(BuildContext context) {
return WillPopScope(
onWillPop: () => _exitApp(context),
child: Scaffold(
appBar: AppBar(
title: const Text('Flutter WebView example'),
// This drop down menu demonstrates that Flutter widgets can be shown over the web view.
actions: <Widget>[
NavigationControls(_controller.future),
SampleMenu(_controller.future),
],
),
code snippet for exit app
WebViewController controllerGlobal;
Future<bool> _exitApp(BuildContext context) async {
if (await controllerGlobal.canGoBack()) {
print("onwill goback");
controllerGlobal.goBack();
} else {
Scaffold.of(context).showSnackBar(
const SnackBar(content: Text("No back history item")),
);
return Future.value(false);
}
}
working demo
full code
import 'dart:async';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';
void main() => runApp(MaterialApp(home: WebViewExample()));
const String kNavigationExamplePage = '''
<!DOCTYPE html><html>
<head><title>Navigation Delegate Example</title></head>
<body>
<p>
The navigation delegate is set to block navigation to the youtube website.
</p>
<ul>
<ul>https://www.youtube.com/</ul>
<ul>https://www.google.com/</ul>
<ul>https://nodejs.org/en</ul>
</ul>
</body>
</html>
''';
class WebViewExample extends StatefulWidget {
#override
_WebViewExampleState createState() => _WebViewExampleState();
}
WebViewController controllerGlobal;
Future<bool> _exitApp(BuildContext context) async {
if (await controllerGlobal.canGoBack()) {
print("onwill goback");
controllerGlobal.goBack();
} else {
Scaffold.of(context).showSnackBar(
const SnackBar(content: Text("No back history item")),
);
return Future.value(false);
}
}
class _WebViewExampleState extends State<WebViewExample> {
final Completer<WebViewController> _controller =
Completer<WebViewController>();
#override
Widget build(BuildContext context) {
return WillPopScope(
onWillPop: () => _exitApp(context),
child: Scaffold(
appBar: AppBar(
title: const Text('Flutter WebView example'),
// This drop down menu demonstrates that Flutter widgets can be shown over the web view.
actions: <Widget>[
NavigationControls(_controller.future),
SampleMenu(_controller.future),
],
),
// We're using a Builder here so we have a context that is below the Scaffold
// to allow calling Scaffold.of(context) so we can show a snackbar.
body: Builder(builder: (BuildContext context) {
return WebView(
initialUrl: 'https://flutter.dev',
javascriptMode: JavascriptMode.unrestricted,
onWebViewCreated: (WebViewController webViewController) {
_controller.complete(webViewController);
},
// TODO(iskakaushik): Remove this when collection literals makes it to stable.
// ignore: prefer_collection_literals
javascriptChannels: <JavascriptChannel>[
_toasterJavascriptChannel(context),
].toSet(),
navigationDelegate: (NavigationRequest request) {
if (request.url.startsWith('https://www.youtube.com/')) {
print('blocking navigation to $request}');
return NavigationDecision.prevent;
}
if (request.url.startsWith('https://flutter.dev/docs')) {
print('blocking navigation to $request}');
return NavigationDecision.prevent;
}
print('allowing navigation to $request');
return NavigationDecision.navigate;
},
onPageFinished: (String url) {
print('Page finished loading: $url');
},
);
}),
floatingActionButton: favoriteButton(),
),
);
}
JavascriptChannel _toasterJavascriptChannel(BuildContext context) {
return JavascriptChannel(
name: 'Toaster',
onMessageReceived: (JavascriptMessage message) {
Scaffold.of(context).showSnackBar(
SnackBar(content: Text(message.message)),
);
});
}
Widget favoriteButton() {
return FutureBuilder<WebViewController>(
future: _controller.future,
builder: (BuildContext context,
AsyncSnapshot<WebViewController> controller) {
if (controller.hasData) {
return FloatingActionButton(
onPressed: () async {
final String url = await controller.data.currentUrl();
Scaffold.of(context).showSnackBar(
SnackBar(content: Text('Favorited $url')),
);
},
child: const Icon(Icons.favorite),
);
}
return Container();
});
}
}
enum MenuOptions {
showUserAgent,
listCookies,
clearCookies,
addToCache,
listCache,
clearCache,
navigationDelegate,
}
class SampleMenu extends StatelessWidget {
SampleMenu(this.controller);
final Future<WebViewController> controller;
final CookieManager cookieManager = CookieManager();
#override
Widget build(BuildContext context) {
return FutureBuilder<WebViewController>(
future: controller,
builder:
(BuildContext context, AsyncSnapshot<WebViewController> controller) {
return PopupMenuButton<MenuOptions>(
onSelected: (MenuOptions value) {
switch (value) {
case MenuOptions.showUserAgent:
_onShowUserAgent(controller.data, context);
break;
case MenuOptions.listCookies:
_onListCookies(controller.data, context);
break;
case MenuOptions.clearCookies:
_onClearCookies(context);
break;
case MenuOptions.addToCache:
_onAddToCache(controller.data, context);
break;
case MenuOptions.listCache:
_onListCache(controller.data, context);
break;
case MenuOptions.clearCache:
_onClearCache(controller.data, context);
break;
case MenuOptions.navigationDelegate:
_onNavigationDelegateExample(controller.data, context);
break;
}
},
itemBuilder: (BuildContext context) => <PopupMenuItem<MenuOptions>>[
PopupMenuItem<MenuOptions>(
value: MenuOptions.showUserAgent,
child: const Text('Show user agent'),
enabled: controller.hasData,
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.listCookies,
child: Text('List cookies'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.clearCookies,
child: Text('Clear cookies'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.addToCache,
child: Text('Add to cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.listCache,
child: Text('List cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.clearCache,
child: Text('Clear cache'),
),
const PopupMenuItem<MenuOptions>(
value: MenuOptions.navigationDelegate,
child: Text('Navigation Delegate example'),
),
],
);
},
);
}
void _onShowUserAgent(
WebViewController controller, BuildContext context) async {
// Send a message with the user agent string to the Toaster JavaScript channel we registered
// with the WebView.
controller.evaluateJavascript(
'Toaster.postMessage("User Agent: " + navigator.userAgent);');
}
void _onListCookies(
WebViewController controller, BuildContext context) async {
final String cookies =
await controller.evaluateJavascript('document.cookie');
Scaffold.of(context).showSnackBar(SnackBar(
content: Column(
mainAxisAlignment: MainAxisAlignment.end,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
const Text('Cookies:'),
_getCookieList(cookies),
],
),
));
}
void _onAddToCache(WebViewController controller, BuildContext context) async {
await controller.evaluateJavascript(
'caches.open("test_caches_entry"); localStorage["test_localStorage"] = "dummy_entry";');
Scaffold.of(context).showSnackBar(const SnackBar(
content: Text('Added a test entry to cache.'),
));
}
void _onListCache(WebViewController controller, BuildContext context) async {
await controller.evaluateJavascript('caches.keys()'
'.then((cacheKeys) => JSON.stringify({"cacheKeys" : cacheKeys, "localStorage" : localStorage}))'
'.then((caches) => Toaster.postMessage(caches))');
}
void _onClearCache(WebViewController controller, BuildContext context) async {
await controller.clearCache();
Scaffold.of(context).showSnackBar(const SnackBar(
content: Text("Cache cleared."),
));
}
void _onClearCookies(BuildContext context) async {
final bool hadCookies = await cookieManager.clearCookies();
String message = 'There were cookies. Now, they are gone!';
if (!hadCookies) {
message = 'There are no cookies.';
}
Scaffold.of(context).showSnackBar(SnackBar(
content: Text(message),
));
}
void _onNavigationDelegateExample(
WebViewController controller, BuildContext context) async {
final String contentBase64 =
base64Encode(const Utf8Encoder().convert(kNavigationExamplePage));
controller.loadUrl('data:text/html;base64,$contentBase64');
}
Widget _getCookieList(String cookies) {
if (cookies == null || cookies == '""') {
return Container();
}
final List<String> cookieList = cookies.split(';');
final Iterable<Text> cookieWidgets =
cookieList.map((String cookie) => Text(cookie));
return Column(
mainAxisAlignment: MainAxisAlignment.end,
mainAxisSize: MainAxisSize.min,
children: cookieWidgets.toList(),
);
}
}
class NavigationControls extends StatelessWidget {
const NavigationControls(this._webViewControllerFuture)
: assert(_webViewControllerFuture != null);
final Future<WebViewController> _webViewControllerFuture;
#override
Widget build(BuildContext context) {
return FutureBuilder<WebViewController>(
future: _webViewControllerFuture,
builder:
(BuildContext context, AsyncSnapshot<WebViewController> snapshot) {
final bool webViewReady =
snapshot.connectionState == ConnectionState.done;
final WebViewController controller = snapshot.data;
controllerGlobal = controller;
return Row(
children: <Widget>[
IconButton(
icon: const Icon(Icons.arrow_back_ios),
onPressed: !webViewReady
? null
: () async {
if (await controller.canGoBack()) {
controller.goBack();
} else {
Scaffold.of(context).showSnackBar(
const SnackBar(content: Text("No back history item")),
);
return;
}
},
),
IconButton(
icon: const Icon(Icons.arrow_forward_ios),
onPressed: !webViewReady
? null
: () async {
if (await controller.canGoForward()) {
controller.goForward();
} else {
Scaffold.of(context).showSnackBar(
const SnackBar(
content: Text("No forward history item")),
);
return;
}
},
),
IconButton(
icon: const Icon(Icons.replay),
onPressed: !webViewReady
? null
: () {
controller.reload();
},
),
],
);
},
);
}
}