9、获取所有特征值(getBLEDeviceCharacteristics)

迈不过友情╰ 2022-04-24 01:06 262阅读 0赞

# wx.getBLEDeviceCharacteristics(Object object) #

> 基础库 1.1.0 开始支持，低版本需做[兼容处理][Link 1]。

获取蓝牙设备某个服务中所有特征值(characteristic)。

## 参数 ##

### Object object ###

<table> 
 <thead> 
  <tr> 
   <th>属性</th> 
   <th>类型</th> 
   <th>默认值</th> 
   <th>必填</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>deviceId</td> 
   <td>string</td> 
   <td>&nbsp;</td> 
   <td>是</td> 
   <td>蓝牙设备 id</td> 
  </tr> 
  <tr> 
   <td>serviceId</td> 
   <td>string</td> 
   <td>&nbsp;</td> 
   <td>是</td> 
   <td>蓝牙服务 uuid，需要使用&nbsp;<code>getBLEDeviceServices</code>&nbsp;获取</td> 
  </tr> 
  <tr> 
   <td>success</td> 
   <td>function</td> 
   <td>&nbsp;</td> 
   <td>否</td> 
   <td>接口调用成功的回调函数</td> 
  </tr> 
  <tr> 
   <td>fail</td> 
   <td>function</td> 
   <td>&nbsp;</td> 
   <td>否</td> 
   <td>接口调用失败的回调函数</td> 
  </tr> 
  <tr> 
   <td>complete</td> 
   <td>function</td> 
   <td>&nbsp;</td> 
   <td>否</td> 
   <td>接口调用结束的回调函数（调用成功、失败都会执行）</td> 
  </tr> 
 </tbody> 
</table>

object.success 回调函数

参数

Object res

<table> 
 <thead> 
  <tr> 
   <th>属性</th> 
   <th>类型</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>characteristics</td> 
   <td>Array.&lt;Object&gt;</td> 
   <td>设备特征值列表</td> 
  </tr> 
 </tbody> 
</table>

**res.characteristics 的结构**

<table> 
 <thead> 
  <tr> 
   <th>属性</th> 
   <th>类型</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>uuid</td> 
   <td>string</td> 
   <td>蓝牙设备特征值的 uuid</td> 
  </tr> 
  <tr> 
   <td>properties</td> 
   <td>Object</td> 
   <td>该特征值支持的操作类型</td> 
  </tr> 
 </tbody> 
</table>

**properties 的结构**

<table> 
 <thead> 
  <tr> 
   <th>属性</th> 
   <th>类型</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>read</td> 
   <td>boolean</td> 
   <td>该特征值是否支持 read 操作</td> 
  </tr> 
  <tr> 
   <td>write</td> 
   <td>boolean</td> 
   <td>该特征值是否支持 write 操作</td> 
  </tr> 
  <tr> 
   <td>notify</td> 
   <td>boolean</td> 
   <td>该特征值是否支持 notify 操作</td> 
  </tr> 
  <tr> 
   <td>indicate</td> 
   <td>boolean</td> 
   <td>该特征值是否支持 indicate 操作</td> 
  </tr> 
 </tbody> 
</table>

lanyatest.wxml代码：

<view class="contentview">
    
      <view  class='myview' >
        
          {
       {info}}
        
    
      </view>
    
      <button type="primary" class="button" bindtap="lanyatest1">1初始化蓝牙</button>
      <button type="primary" class="button" bindtap="lanyatest2">2获取蓝牙状态</button>
      <button type="primary" class="button" bindtap="lanyatest3">3搜索周边设备</button>
      <button type="primary" class="button" bindtap="lanyatest4">4获取所有设备</button>
      <block wx:for="{
       {devices}}" wx:key="{
       {test}}">
        <button type="primary" class="button" id="{
       {item.deviceId}}" style='background-color:red' bindtap="lanyaconnect">5连接{
       {item.name}}         </button>
      </block>
      <button type="primary" class="button" bindtap="lanyatest6">6停止搜索周边蓝牙设备</button>
      <button type="primary" class="button" bindtap="lanyatest7">7获取所有service</button>
      <button type="primary" class="button" bindtap="lanyatest8">8获取所有特征值</button>
    </view>

lanyatest.js代码：

// pages/lanyatest/lanyatest.js
    Page({
    
      /**
       * 页面的初始数据
       */
      data: {
        info:"未初始化蓝牙适配器",
        connectedDeviceId:"",
        deviceId:"",
        services:"",
        servicesUUID:"0000FF00-0000-1000-8000-00805F9B34FB",
        serviceId:""
      },
    
      lanyatest1(event){
        var that = this;
        wx.openBluetoothAdapter({
          success: function (res) {
            console.log('初始化蓝牙适配器成功')
            //页面日志显示
            that.setData({
              info: '初始化蓝牙适配器成功'
            })
          },
          fail: function (res) {
            console.log('请打开蓝牙和定位功能')
            that.setData({
              info: '请打开蓝牙和定位功能'
            })
          }
        })
      },
    
    
    
      lanyatest2(event){
        var that = this;
        wx.getBluetoothAdapterState({
    
          success: function (res) {
    
            //打印相关信息
            console.log(JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available);
    
            that.setData({
              info: JSON.stringify(res.errMsg) +"\n蓝牙是否可用：" + res.available
            })
    
          },
          fail: function (res) {
    
            //打印相关信息
            console.log(JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available);
    
            that.setData({
              info: JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available
            })
    
          }
          
        })
    
      },
    
    
    
      lanyatest3(event){
        var that = this;
        wx.startBluetoothDevicesDiscovery({
          services: ['FEE7'], //如果填写了此UUID，那么只会搜索出含有这个UUID的设备，建议一开始先不填写或者注释掉这一句
          success: function (res) {
            that.setData({
              info: "搜索设备" + JSON.stringify(res),
            })
            console.log('搜索设备返回' + JSON.stringify(res))
    
          }
        })
    
      },
    
    
    
    
      lanyatest4(event){
        var that = this;
        wx.getBluetoothDevices({
          success: function (res) {
    
            that.setData({
              info: "设备列表\n" + JSON.stringify(res.devices),
              devices: res.devices
            })
            console.log('搜设备数目：' + res.devices.length)
            console.log('设备信息：\n' + JSON.stringify(res.devices)+"\n")
          }
        })
    
      },
    
    
    
      lanyaconnect(event){
        var that = this;
        wx.createBLEConnection({
          deviceId: event.currentTarget.id,
          success: function (res) {
            console.log('调试信息：' + res.errMsg);
            that.setData({
              connectedDeviceId: event.currentTarget.id,
              info: "MAC地址：" + event.currentTarget.id  + '  调试信息：' + res.errMsg,
              
            })
          },
          fail: function () {
            console.log("连接失败");
          },
    
        })
    
      },
    
    
      lanyatest6(event){
        var that = this;
        wx.stopBluetoothDevicesDiscovery({
          success: function (res) {
            console.log("停止搜索" + JSON.stringify(res.errMsg));
            that.setData({
              info: "停止搜索"  + JSON.stringify(res.errMsg),
            })
          }
        })
    
      },
    
    
    
      lanyatest7(event){
        var that = this;
        wx.getBLEDeviceServices({
          // 这里的 deviceId 需要在上面的 getBluetoothDevices 或 onBluetoothDeviceFound 接口中获取
          deviceId: that.data.connectedDeviceId,
          success: function (res) {
            console.log('services UUID:\n', JSON.stringify(res.services));
            for (var i = 0; i < res.services.length; i++) {
              console.log("第"+(i+1) + "个UUID:" + res.services[i].uuid+"\n")
              
    
            }
            that.setData({
              services: res.services,
              info: JSON.stringify(res.services),
            })
          }
        })
    
      },
    
    
    
      lanyatest8(event){
        var that = this;
        var myUUID = that.data.servicesUUID;//具有读、写、通知、属性的服务uuid
        console.log('UUID' + myUUID)
        wx.getBLEDeviceCharacteristics({
          // 这里的 deviceId 需要在上面的 getBluetoothDevices 或 onBluetoothDeviceFound 接口中获取
          deviceId: that.data.connectedDeviceId,
          // 这里的 serviceId 需要在上面的 getBLEDeviceServices 接口中获取
          serviceId: myUUID,
          success: function (res) {
            console.log("%c getBLEDeviceCharacteristics", "color:red;");
            for (var i = 0; i < res.characteristics.length; i++) {
              console.log('特征值：' + res.characteristics[i].uuid)
    
              if (res.characteristics[i].properties.notify) {
                console.log("notifyServicweId：", myUUID);
                console.log("notifyCharacteristicsId：", res.characteristics[i].uuid);
                that.setData({
                  notifyServicweId: myUUID,
                  notifyCharacteristicsId: "0000FF01-0000-1000-8000-00805F9B34FB",//手动设置notifyCharacteristicsId为这个UUID，为了方便写死在这里
    
                })
                console.log("打印notifyCharacteristicsId")
                console.log(that.data.notifyCharacteristicsId)
              }
              if (res.characteristics[i].properties.write) {
                console.log("writeServicweId：", myUUID);
                console.log("writeCharacteristicsId：", res.characteristics[i].uuid);
                that.setData({
                  writeServicweId: myUUID,
                  //writeCharacteristicsId: res.characteristics[i].uuid,
                  writeCharacteristicsId: "0000FF02-0000-1000-8000-00805F9B34FB",//手动设置writeCharacteristicsId为这个UUID，为了方便写死在这里
                })
    
              }
    
            }
            console.log('device getBLEDeviceCharacteristics:', res.characteristics);
    
            that.setData({
              msg: JSON.stringify(res.characteristics),
            })
          },
          fail: function () {
            console.log("fail");
          },
    
        })
    
    
    
    
      },
    
    
    
    //我删除了自动生成的生命周期函数
    
    })

lanyatest.wxss代码：

/* pages/lanyatest/lanyatest.wxss */
    .vertical{
      display: flex;
      flex-direction: column;
    }
    
    /**index.wxss**/
    .horizontal{
      display: flex;
      flex-direction: row;
    }
    
    .btinfo{
      height:100px;
    }
    
    .contentview {
    margin: 0 10px;
    }
     
    .button {
    margin: 5px;
    }
    
    .myview{
      height:200px;
      word-break:break-all;/* 自动换行 */
    }

# 真机调试结果： #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70 1][]

# 开发心得： #

这一步是最坑的，很多人都卡在这一步上面，在开发微信之前，已经测试过安卓app连接蓝牙，可以正常通讯，安卓app使用的是数据透传的UUID是0xFF00。

研究了一下微信有个airsync协议，UUID是为 0xFEE7，以为小程序也需要使用这个0xFEE7的UUID，结果在这里卡了好久，怎样都无法通讯，后来发现微信小程序也是使用0xFF00的UUID进行通讯，而airsync则是用来做别的事的：详情看下方链接[https://www.cnblogs.com/yueqian-scut/p/5359254.html][https_www.cnblogs.com_yueqian-scut_p_5359254.html]

此处获取的特征值是0xFF00这个service的characteristics，总共有4个我们使用的是最上面的两个，就是写入和通知，基本数据透传通讯靠这两个就够了。这是我使用的蓝牙模块，别的蓝牙模块可能不一样，请仔细阅读数据手册

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70 2][]

特别注意：UUID的值请大写，这是另一个坑，在安卓上，uuid的值小写也可以，但是在苹果微信客户端，小写的uuid会提示搜不到

[Link 1]: https://developers.weixin.qq.com/miniprogram/dev/framework/compatibility.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70]: /images/20220221/1edc7b4a6c5341eba2936b8b5e3f64b9.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70 1]: /images/20220221/3970bf197c09473c8ffd97b00d2e8b89.png
[https_www.cnblogs.com_yueqian-scut_p_5359254.html]: https://www.cnblogs.com/yueqian-scut/p/5359254.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM0MjM0MDg3_size_16_color_FFFFFF_t_70 2]: /images/20220221/b0964f6b88a64e17b3d919495e72ef61.png