flutter调用原生实现连接控制称重设备

最近接了一个新需求：

内容： 通过手机app实现蓝牙连接称重设备，实现app获取设备重量并接入业务

语言以及工具：

        1、flutter  + java安卓原生      

        2、某某牌蓝牙称重蓝牙硬件板块（称榜上拆下来的）：

前面走过的坑（只对于我接手的项目而已，并不是说以下文档插件不好）：

1、flutter_weigh_serial 1.0.0+2

这个插件我试了，但是和我的gradle版本不兼容，就被我舍弃了

2、bluetooth_print  这个热敏蓝牙打印插件我也试了，可以搜索到该蓝牙设备，但是连接不了

 最后没办法，还是老老实实写原生方法

1、建立flutter与原生通道

new MethodChannel(Objects.requireNonNull(getFlutterEngine()).getDartExecutor().getBinaryMessenger(), WEIGHTGET)
                .setMethodCallHandler((call, result) -> {
                    if (call.method.equals("getCount")) {

                        System.out.println("连接状态" + isopen);
                        if(isopen){
                            mBLE_Service.disconnect();
                            isopen = false;
                            result.success(isopen);
                            return;
                        }
                        isopen = true;

                        ///==========================
                        Intent data = getIntent();
                        mdevice  = data.getParcelableExtra("Device");
                        UART_UUID = data.getStringExtra("DeviceUART");
                        TXO_UUID = data.getStringExtra("DeviceTXO");
                        RXI_UUID = data.getStringExtra("DeviceRXI");

//                        sevice = UUID.fromString(UART_UUID);
//                        txo = UUID.fromString(TXO_UUID);
//                        rxi = UUID.fromString(RXI_UUID);

                        sevice = UUID.fromString("0000FFE0-0000-1000-8000-00805F9B34FB");
                        txo = UUID.fromString("0000FFE1-0000-1000-8000-00805F9B34FB");
                        rxi = UUID.fromString("0000FFE1-0000-1000-8000-00805F9B34FB");



                        // 如果 mdevice 为 null 或者需要设置默认地址
                        if (mdevice == null || mdevice.getAddress() == null || mdevice.getAddress().isEmpty()) {
                            String defaultAddress = "88:25:83:F4:F7:4A";
                            mdevice = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(defaultAddress);
                        }
                        
                        mBLE_Service.setUUID(sevice,txo,rxi);
                        mBLE_Service.disconnect();
                        mBLE_Service.connect(mdevice, this);

                        result.success(isopen);

                        /======================

                    } else {
                        result.notImplemented();
                    }
                });

        上面的UUID直接写死固定设备，包括设备的蓝牙地址我都是先直接写死

2、监听蓝牙模块的响应数据

SpBLE mBLE_Service;
mBLE_Service = new SpBLE(this,mHandler);

 封装好的蓝牙服务类文件

package com.example.yunhan_demo;

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

/**
 * This class does all the work for setting up and managing Bluetooth
 * connections with other devices. It has a thread that listens for
 * incoming connections, a thread for connecting with a device, and a
 * thread for performing data transmissions when connected.
 */
public class BluetoothChatService {
    // Debugging
    private static final String TAG = "BluetoothChatService";
    private static final boolean D = true;

    // Name for the SDP reco