uniapp 蓝牙连接设备 下发命令 监听蓝牙与设备的连接状态(兼容 微信小程序和支付宝小程序)

1：创建蓝牙需要调用的Api文件 ly.js

// import { TextDecoder } from 'text-encoding-utf-8';
let bluetoothOpen = false; // 手机蓝牙是否打开
let bluetoothConnect = false; // 设备和蓝牙是否连接
let isHaveDevice = false; // 是否查找到设备
let deviceId = null; // 设备id
let serviceId = null; // 服务id
let notify = null; // 监听uuid
let writeId = null; // 写入uuid
/**
 * 获取手机蓝牙是否打开
 */
const getBluetoothState = () => {
	// 主机模式
	return new Promise((resolve, reject) => {
		// mode: 'central',
		uni.openBluetoothAdapter({
			success: (r) => {
				console.log("蓝牙初始化成功");
				// 获取蓝牙的匹配状态
				uni.getBluetoothAdapterState({
					success: function(row) {
						console.log('蓝牙状态：', row.available);
						if (row.available) {
							bluetoothOpen = true;
							resolve();
						} else {
							// 请开启蓝牙
							uni.showToast({
								title: '请打开蓝牙',
								icon: 'none'
							})
							bluetoothOpen = false;
							bluetoothConnect = false;

							reject();
						}
					},
					fail: function(err) {
						// 请开启蓝牙
						uni.showToast({
							title: '请打开蓝牙',
							icon: 'none'
						})
						bluetoothOpen = false;
						bluetoothConnect = false;
						reject();
					}
				})
			},
			fail: (err) => {
				// 请开启蓝牙
				console.log('蓝牙初始化失败'+ JSON.stringify(err));
				uni.showToast({
					title: '请前往手机设置，打开此APP蓝牙权限',
					icon: 'none'
				})
				bluetoothOpen = false;
				bluetoothConnect = false;
				reject();
			}
		});
	});
};
/**
 * 开始搜索蓝牙设备
 */
const discoveryBluetooth = () => {
	return new Promise((resolve) => {
		uni.startBluetoothDevicesDiscovery({
			success(res) {
				console.log('搜索蓝牙外围设备完成', res)
				setTimeout(() => {
					resolve();
				}, 2000);
			}
		});
	})
};
// 关闭蓝牙搜索
const stopDiscoveryBluetooth = () => {
	uni.stopBluetoothDevicesDiscovery({
		success(r) {
			console.log("停止搜索蓝牙设备", r);
		}
	});
};
/**
 * 获取搜索到的设备信息
 */
const getBluetoothDevices = (deviceName) => {
	return new Promise((resolve, reject) => {
		uni.getBluetoothDevices({
			success(res) {
				console.log('获取搜索到的设备信息', res.devices);

				bluetoothConnect = false;
				// 过滤掉name为空或者未知设备的设备
				let devices = res.devices.filter(function(obj) {
					return obj.name !== "" && obj.name !== "未知设备"
				});
				console.log('有名称蓝牙列表', devices, deviceName);
				devices && devices.forEach(item => {
					if (item.name && item.name === deviceName) {
						deviceId = item.deviceId;
						isHaveDevice = true;
						resolve(isHaveDevice);
						console.log('设备ID', deviceId, item);
					}
				});
			},
			fail: function() {
				console.log('搜索蓝牙设备失败');
				bluetoothConnect = false;
				isHaveDevice = false;
				reject(isHaveDevice);
			},
			complete: function() {
				console.log("蓝牙搜索完成");
				// // 是否具有当前设备
				// if (deviceId) {
				// 	isHaveDevice = true;
				// } else {
				// 	isHaveDevice = false;
				// }
				// resolve(isHaveDevice);
			}
		});
	});
}
/**
 * 连接蓝牙
 * deviceId 蓝牙设备id
 */
const connectBluetooth = () => {
	return new Promise((resolve, reject) => {
		uni.createBLEConnection({
			deviceId: deviceId, // 设备id
			success() {
				bluetoothConnect = true;
				console.log('连接蓝牙成功', deviceId);
				// 蓝牙连接成功后关闭蓝牙搜索
				stopDiscoveryBluetooth();
				resolve();
				// 获取服务id
				getServiceId();
			},
			fail(err) {
				bluetoothConnect = false;
				console.log("蓝牙连接失败",err);
				reject();
			}
		});
	});
};
// 获取服务id
const getServiceId = () => {
	uni.getBLEDeviceServices({
		deviceId: deviceId,
		success(res) {
			let model = res.services[0];
			serviceId = model.uuid;
			console.log("获取服务Id",serviceId, res)
			// 调用蓝牙监听和写入功能
			getCharacteId();
		}
	})
};
// 获取蓝牙低功耗设备某个服务中所有特征
const getCharacteId = () => {
	uni.getBLEDeviceCharacteristics({
		deviceId: deviceId, // 蓝牙设备id
		serviceId: serviceId, // 蓝牙服务UUID
		success(res) {
			console.log('数据监听', res);
			res.characteristics.forEach(item => {
				// 003
				if (item.properties.notify === true) {
					// 监听
					
					// 微信
					// #ifdef MP-WEIXIN
					notify = item.uuid;
					
					// #endif
					
					//支付宝
					// #ifdef MP-ALIPAY
						notify =  item.characteristicId;
					// #endif
					startNotice();
				}
				// 002
				if (item.properties.write === true) {
					// 写入 
					
					// 微信
					// #ifdef MP-WEIXIN
					let writeId = item.uuid;
					uni.setStorageSync("writeId", item.uuid);
					// #endif
					
					//支付宝
					// #ifdef MP-ALIPAY
					let writeId = item.serviceId;
					uni.setStorageSync("writeId", item.characteristicId);
					// #endif
					
					
				}
			});
		},
		fail(err) {
			console.log("数据监听失败", err)
		}
	})
};
// 启用低功耗蓝牙设备特征值变化时的notify功能
const startNotice = () => {
	uni.notifyBLECharacteristicValueChange({
		characteristicId: notify,
		deviceId: deviceId,
		serviceId: serviceId,
		state: true,
		success(res) {
			// 监听低功耗蓝牙设备的特征值变化
			uni.onBLECharacteristicValueChange(result => {
				console.log("监听低功耗蓝牙设备的特征值变化", result);
				if (result.value) {
					// let decoder = new TextDecoder('utf-8');
					// let data = decoder.decode(result.value);
					// let data = result.value;
					console.log('帽子返回数据', result)
				}
			})
		}
	});
};


// 蓝牙发送数据
const writeData = (buffer) => {
	return new Promise((resolve, reject) => {
		console.log(uni.getStorageSync("writeId"),'下发命令1writeId');
		console.log(deviceId,'下发命令2deviceId');
		console.log(serviceId,'下发命令3serviceId');
		console.log(buffer,'下发命令4buffer');
		
		uni.writeBLECharacteristicValue({
			characteristicId: uni.getStorageSync("writeId"),
			deviceId: deviceId,
			serviceId: serviceId,
			value: buffer,
			success(res) {
				console.log("writeBLECharacteristicValue success", res);
				resolve();
			},
			fail(err) {
				console.log("报错了", err);
				reject();
			}
		});
	});
};


const createBlec = () => {
	uni.createBLEConnection({
		deviceId:deviceId,
		success(res) {
			console.log(res, '断开成功')
		},
		fail(err) {
			console.log("断开失败", err);
		}
	})
}

const BLECStateChange=()=>{
	 return new Promise((resolve, reject) => {
		 uni.onBLEConnectionStateChange(function (res) {
			 // 该方法回调中可以用于处理连接意外断开等异常情况
			 console.log(`device ${res.deviceId} state has changed, connected: ${res.connected}`)
			 return resolve(res)
		  
		 })
	 })
	
}




// closeBLEConnection  deviceId  断开蓝牙
export default {
	getBluetoothState,
	discoveryBluetooth,
	stopDiscoveryBluetooth,
	getBluetoothDevices,
	connectBluetooth,
	getServiceId,
	getCharacteId,
	startNotice,
	writeData,
	createBlec,
	BLECStateChange
};

2 在页面中使用index.vue