有人可以帮助我如何/在哪里进行更改，以便 _scanBarcode 的输出可以放入 _runFilter 中，您也可以在其中键入搜索项目。
当我在搜索字段中输入时，它工作正常，但我想添加 qr 扫描功能，但不知道将结果放在 _runFilter 函数中的位置。
我以为我必须将它放在脚手架文本字段中，但我想我错了。
// main.dart
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_barcode_scanner/flutter_barcode_scanner.dart';
import 'sql_helper.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return MaterialApp(
// Remove the debug banner
debugShowCheckedModeBanner: false,
title: 'Floormanager JOOST',
theme: ThemeData(
primarySwatch: Colors.orange,
),
home: const HomePage());
}
}
class HomePage extends StatefulWidget {
const HomePage({Key? key}) : super(key: key);
@override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
// All Items
List<Map<String, dynamic>> _journals = [];
//bool _isLoading = true;
// This function is used to fetch all data from the database
void _refreshJournals() async {
final data = await SQLHelper.getItems();
setState(() {
_journals = data;
//_isLoading = false;
});
}
// This list holds the data for the list view
List<Map<String, dynamic>> _alljournals = [];
@override
void initState() {
_alljournals = _journals;
super.initState();
_refreshJournals(); // Loading the diary when the app starts
}
// This function is called whenever the text field changes
void _runFilter(String enteredKeyword) {
List<Map<String, dynamic>> results = [];
if (enteredKeyword.isEmpty) {
// if the search field is empty or only contains white-space, we'll display all items
results = _journals;
} else {
results = _journals
.where((item) =>
item["title"].toLowerCase().contains(enteredKeyword.toLowerCase()))
.toList();
// we use the toLowerCase() method to make it case-insensitive
}
// Refresh the UI
setState(() {
_alljournals = results;
});
}
String _scanBarcode = '';
Future<void> startBarcodeScanStream() async {
FlutterBarcodeScanner.getBarcodeStreamReceiver(
'#ff6666', 'Cancel', true, ScanMode.BARCODE)!
.listen((barcode) => debugPrint(barcode));
}
Future<void> scanQR() async {
String barcodeScanRes;
// Platform messages may fail, so we use a try/catch PlatformException.
try {
barcodeScanRes = await FlutterBarcodeScanner.scanBarcode(
'#ff6666', 'Cancel', true, ScanMode.QR);
debugPrint(barcodeScanRes);
} on PlatformException {
barcodeScanRes = 'Failed to get platform version.';
}
if (!mounted) return;
setState(() {
_scanBarcode = barcodeScanRes;
});
}
// Platform messages are asynchronous, so we initialize in an async method.
Future<void> scanBarcodeNormal() async {
String barcodeScanRes;
// Platform messages may fail, so we use a try/catch PlatformException.
try {
barcodeScanRes = await FlutterBarcodeScanner.scanBarcode(
'#ff6666', 'Cancel', true, ScanMode.DEFAULT);
} on PlatformException {
barcodeScanRes = 'Failed to get platform version.';
}
if (!mounted) return;
setState(() {
_scanBarcode = barcodeScanRes;
});
}
final TextEditingController _titleController = TextEditingController();
final TextEditingController _descriptionController = TextEditingController();
final TextEditingController _aantalController = TextEditingController();
// This function will be triggered when the floating button is pressed
// It will also be triggered when you want to update an item
void _showForm(int? id) async {
if (id != null) {
// id == null -> create new item
// id != null -> update an existing item
final existingJournal =
_journals.firstWhere((element) => element['id'] == id);
_titleController.text = existingJournal['title'];
_descriptionController.text = existingJournal['description'];
_aantalController.text = existingJournal['aantal'];
}
showModalBottomSheet(
context: context,
elevation: 5,
isScrollControlled: true,
builder: (_) => Container(
padding: EdgeInsets.only(
top: 15,
left: 15,
right: 15,
// this will prevent the soft keyboard from covering the text fields
bottom: MediaQuery.of(context).viewInsets.bottom + 120,
),
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.end,
children: [
TextField(
controller: _titleController,
decoration: const InputDecoration(hintText: 'Title'),
),
const SizedBox(
height: 10,
),
TextField(
controller: _descriptionController,
decoration: const InputDecoration(hintText: 'Description'),
),
const SizedBox(
height: 20,
),
TextField(
controller: _aantalController,
decoration: const InputDecoration(hintText: 'Aantal'),
),
const SizedBox(
height: 10,
),
ElevatedButton(
onPressed: () async {
// Save new journal
if (id == null) {
await _addItem();
}
if (id != null) {
await _updateItem(id);
}
// Clear the text fields
_titleController.text = '';
_descriptionController.text = '';
_aantalController.text = '';
// Close the bottom sheet
Navigator.of(context).pop();
},
child: Text(id == null ? 'Create New' : 'Update'),
)
],
),
));
}
// Insert a new journal to the database
Future<void> _addItem() async {
await SQLHelper.createItem(
_titleController.text, _descriptionController.text, _aantalController.text);
_refreshJournals();
}
// Update an existing journal
Future<void> _updateItem(int id) async {
await SQLHelper.updateItem(
id, _titleController.text, _descriptionController.text, _aantalController.text);
_refreshJournals();
}
// Delete an item
void _deleteItem(int id) async {
await SQLHelper.deleteItem(id);
ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
content: Text('Succesvol verwijderd!'),
));
_refreshJournals();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Floormanager JOOST'),
),
body: Padding(
padding: const EdgeInsets.all(10),
child: Column(
children: [
const SizedBox(
height: 20,
),
TextField(
onChanged: (value) => _runFilter(value),
decoration: const InputDecoration(
labelText: 'Search', suffixIcon: Icon(Icons.search)),
),
const SizedBox(
height: 20,
),
Expanded(
child: _alljournals.isNotEmpty
? ListView.builder(
itemCount: _alljournals.length,
itemBuilder: (context, index) => Card(
key: ValueKey(_alljournals[index]["id"]),
color: Colors.amberAccent,
elevation: 4,
margin: const EdgeInsets.symmetric(vertical: 10),
child: ListTile(
leading: Text(
_alljournals[index]["id"].toString(),
style: const TextStyle(fontSize: 24),
),
title: Text(_alljournals[index]['title']),
subtitle: Text(
'${_alljournals[index]["aantal"].toString()} stuks'),
trailing: SizedBox(
width: 100,
child: Row(
children: [
IconButton(
icon: const Icon(Icons.edit),
onPressed: () => _showForm(_alljournals[index]['id']),
),
IconButton(
icon: const Icon(Icons.delete),
onPressed: () =>
_deleteItem(_alljournals[index]['id']),
),
],
),
)),
),
)
: const Text(
'No results found',
style: TextStyle(fontSize: 24),
),
),
],
),
),
floatingActionButton: Stack(
fit: StackFit.expand,
children: [
Positioned(
left: 90,
bottom: 20,
child: FloatingActionButton(
onPressed: () => _showForm(null),
),
),
Positioned(
left: 30,
bottom: 20,
child: FloatingActionButton(
onPressed: () => scanQR(),
child: const Text('QR scan')),
)
],
),
);
}
}
获取二维码结果后，调用filter方法即可：
setState(() {
_scanBarcode = barcodeScanRes;
_runFilter(_scanBarCode);
});