cabbi
commented
9 months ago Hi,
Dart wise I don't see mistakes in your code. Flutter wise, I need to understand where and when are you calling your sendFrameWriteSingleRegister method.
You can use Provider to notify your widget on any change of the modbus register. Here an example:
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:modbus_client/modbus_client.dart';
import 'package:modbus_client_serial/modbus_client_serial.dart';
var _modbusClientSerialRtu = ModbusClientSerialRtu(portName: "COM2", unitId: 1);
class ModbusRegisterModel extends ChangeNotifier {
int? registerId;
dynamic registerValue;
void update(int registerId, dynamic registerValue) {
this.registerId = registerId;
this.registerValue = registerValue;
notifyListeners();
}
}
void sendFrameWriteSingleRegister(
ModbusRegisterModel model, int addr, int register, int data) async {
// Create ModbusInt16Register
var _reg = ModbusInt16Register(
name: "Registrador $register",
address: register,
type: ModbusElementType.holdingRegister,
onUpdate: (self) {
print("Register updated!");
model.update(self.address, self.value);
},
offset: 0,
);
// Send Modbus frame
try {
await _modbusClientSerialRtu.send(_reg.getWriteRequest(data));
} catch (err) {
// Handle the error appropriately
print("Error sending Modbus frame: $err");
}
}
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Modbus Demo',
theme: ThemeData.dark(),
home: Scaffold(
appBar: AppBar(title: const Text('Modbus Demo')),
body: const Center(child: ModbusElementWidget())),
);
}
}
class ModbusElementWidget extends StatelessWidget {
const ModbusElementWidget({super.key});
@override
Widget build(BuildContext context) {
// Capture model changes
return ChangeNotifierProvider<ModbusRegisterModel>(
// Create the model
create: (_) => ModbusRegisterModel(),
builder: (context, child) {
// Here we are watching at this model (getting notified on its changes)
var model = context.watch<ModbusRegisterModel>();
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text("Register ${model.registerId} : ${model.registerValue}"),
const Divider(),
ElevatedButton.icon(
onPressed: () {
// NOTE: you might get the register attributes from somewhere!
sendFrameWriteSingleRegister(model, 400001, 400001, 123);
},
icon: const Icon(Icons.send),
label: const Text("Send"),
)
],
);
});
}
}
bruno-embtech
Hello, I'm attempting to create an abstraction of this package for use in my application, but I'm encountering issues with asynchronous execution. The UI freezes while the function is running. I'm still learning Flutter and Dart, and I've successfully implemented simple async tasks in the past.
Here's a snippet of the function:
I'd appreciate any suggestions or examples to address the UI freezing issue.