my.startBluetoothDevicesDiscovery

2021-07-21 11:23

Use this API to start discovering bluetooth devices. You can find the results in the API my.onBluetoothDeviceFound.

Note:
To avoid consuming too many system resources, stop the search by calling the API my.stopBluetoothDevicesDiscoveryafter you find and connect to the device.

Currently simulation in IDE is not supported. Please debug in the production environment.

Code Sample

copy

/* .acss */
.help-info {
  padding:10px;
  color:#000000;
}
.help-title {
  padding:10px;
  color:#FC0D1B;
}

copy

// .json
{
    "defaultTitle": "Bluetooth"
}

copy

<!-- .axml-->
<view class="page">
  <view class="page-description">Bluetooth API</view>
  <view class="page-section">
    <view class="page-section-title">The Bluetooth state</view>
    <view class="page-section-demo">
       <button type="primary" onTap="openBluetoothAdapter">Initialize Bluetooth</button>
       <button type="primary" onTap="closeBluetoothAdapter">Close Bluetooth</button>
       <button type="primary" onTap="getBluetoothAdapterState">Obtain Bluetooth state</button>
    </view>
    <view class="page-section-title">Scan the Bluetooth device</view>
    <view class="page-section-demo">
       <button type="primary" onTap="startBluetoothDevicesDiscovery">Start searching</button>
       <button type="primary" onTap="getBluetoothDevices">All devices found</button>
       <button type="primary" onTap="getConnectedBluetoothDevices">All devices connected</button>
       <button type="primary" onTap="stopBluetoothDevicesDiscovery">Stop searching</button>
    </view>
    <view class="page-section-title">Connect the device</view>
    <view class="page-section-demo">
       <input class="input" onInput="bindKeyInput" type="{{text}}" placeholder="Enter the device ID of the device to connect"></input>
       <button type="primary" onTap="connectBLEDevice">Connect the device</button>
       <button type="primary" onTap="getBLEDeviceServices">Obtain device services</button>
       <button type="primary" onTap="getBLEDeviceCharacteristics">Obtain read and write characteristics</button>
       <button type="primary" onTap="disconnectBLEDevice">Disconnect the device</button>
    </view>
     <view class="page-section-title">Read and write data</view>
     <view class="page-section-demo">
       <button type="primary" onTap="notifyBLECharacteristicValueChange">Listens to the characteristic data change</button>
       <button type="primary" onTap="readBLECharacteristicValue">Read data</button>
       <button type="primary" onTap="writeBLECharacteristicValue">Write data</button>
       <button type="primary" onTap="offBLECharacteristicValueChange">Un-listens to characteristic value</button>
    </view>
     <view class="page-section-title">Other events</view>
     <view class="page-section-demo">
       <button type="primary" onTap="bluetoothAdapterStateChange">Changes of the Bluetooth state</button>
       <button type="primary" onTap="offBluetoothAdapterStateChange">Un-listens to Bluetooth state</button>
       <button type="primary" onTap="BLEConnectionStateChanged">Changes of Bluetooth connection state</button>
       <button type="primary" onTap="offBLEConnectionStateChanged">Un-listens to Bluetooth connection state</button>
       
    </view>
  </view>
</view>

copy

// .js
Page({
  data: {
    devid: '0D9C82AD-1CC0-414D-9526-119E08D28124',
    serid: 'FEE7',
    notifyId: '36F6',
    writeId: '36F5',
    charid: '',
    alldev: [{ deviceId: '' }],
  },

  //Obtain the Bluetooth state
  openBluetoothAdapter() {
    my.openBluetoothAdapter({
      success: res => {
        if (!res.isSupportBLE) {
          my.alert({ content: 'Sorry, your mobile Bluetooth is unavailable temporarily' });
          return;
        }
        my.alert({ content: 'Succeeded to initialize!' });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },
  closeBluetoothAdapter() {
    my.closeBluetoothAdapter({
      success: () => {
        my.alert({ content: 'Bluetooth closed!' });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },
  getBluetoothAdapterState() {
    my.getBluetoothAdapterState({
      success: res => {
        if (!res.available) {
          my.alert({ content: 'Sorry, your mobile Bluetooth is unavailable temporarily' });
          return;
        }
        my.alert({ content: JSON.stringify(res) });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },

  //Scan the Bluetooth device
  startBluetoothDevicesDiscovery() {
    my.startBluetoothDevicesDiscovery({
      allowDuplicatesKey: false,
      success: () => {
        my.onBluetoothDeviceFound({
          success: res => {
            // my.alert({content:'Listens to new device'+JSON.stringify(res)});
            var deviceArray = res.devices;
            for (var i = deviceArray.length - 1; i >= 0; i--) {
              var deviceObj = deviceArray[i];
              //Pair the target device with the device name or broadcast data, and then record the device ID for later use.
              if (deviceObj.name == this.data.name) {
                my.alert({ content: 'Target device is found' });
                my.offBluetoothDeviceFound();
                this.setData({
                  deviceId: deviceObj.deviceId,
                });
                break;
              }
            }
          },
          fail: error => {
            my.alert({ content: 'Failed to listen to new device' + JSON.stringify(error) });
          },
        });
      },
      fail: error => {
        my.alert({ content: 'Failed to start scanning' + JSON.stringify(error) });
      },
    });
  },

  //Stop scanning
  stopBluetoothDevicesDiscovery() {
    my.stopBluetoothDevicesDiscovery({
      success: res => {
        my.offBluetoothDeviceFound();
        my.alert({ content: 'Succeeded!' });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },

  //Obtain the connected device
  getConnectedBluetoothDevices() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connecting devices!' });
          return;
        }
        my.alert({ content: JSON.stringify(res) });
        devid = res.devices[0].deviceId;
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },

  //Obtain all searched devices
  getBluetoothDevices() {
    my.getBluetoothDevices({
      success: res => {
        my.alert({ content: JSON.stringify(res) });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },
  bindKeyInput(e) {
    this.setData({
      devid: e.detail.value,
    });
  },

  //Connect the device
  connectBLEDevice() {
    my.connectBLEDevice({
      deviceId: this.data.devid,
      success: res => {
        my.alert({ content: 'Succeeded to connect!' });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },

  //Disconnect the device
  disconnectBLEDevice() {
    my.disconnectBLEDevice({
      deviceId: this.data.devid,
      success: () => {
        my.alert({ content: 'Succeeded to disconnect!' });
      },
      fail: error => {
        my.alert({ content: JSON.stringify(error) });
      },
    });
  },

  //Obtain the services of the connected device
  getBLEDeviceServices() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connected devices' });
          return;
        }
        my.getBLEDeviceServices({
          deviceId: this.data.devid,
          success: res => {
            my.alert({ content: JSON.stringify(res) });
            this.setData({
              serid: res.services[0].serviceId,
            });
          },
          fail: error => {
            my.alert({ content: JSON.stringify(error) });
          },
        });
      },
    });
  },

  //Obtain the char ID of the connected device, read and write characteristics are respectively screened out.
  getBLEDeviceCharacteristics() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connected devices' });
          return;
        }
        this.setData({
          devid: res.devices[0].deviceId,
        });
        my.getBLEDeviceCharacteristics({
          deviceId: this.data.devid,
          serviceId: this.data.serid,
          success: res => {
            my.alert({ content: JSON.stringify(res) });
            //See the related document for more information of the properties of the characteristics. Pair the characteristics according to the properties and record the value for later use.
            this.setData({
              charid: res.characteristics[0].characteristicId,
            });
          },
          fail: error => {
            my.alert({ content: JSON.stringify(error) });
          },
        });
      },
    });
  },

  //Read and write data
  readBLECharacteristicValue() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connected devices' });
          return;
        }
        this.setData({
          devid: res.devices[0].deviceId,
        });
        my.readBLECharacteristicValue({
          deviceId: this.data.devid,
          serviceId: this.data.serid,
          characteristicId: this.data.notifyId,
          //1、Android reading service
          // serviceId:'0000180d-0000-1000-8000-00805f9b34fb',
          // characteristicId:'00002a38-0000-1000-8000-00805f9b34fb',
          success: res => {
            my.alert({ content: JSON.stringify(res) });
          },
          fail: error => {
            my.alert({ content: 'Failed to read' + JSON.stringify(error) });
          },
        });
      },
    });
  },
  writeBLECharacteristicValue() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connected devices' });
          return;
        }
        this.setData({
          devid: res.devices[0].deviceId,
        });
        my.writeBLECharacteristicValue({
          deviceId: this.data.devid,
          serviceId: this.data.serid,
          characteristicId: this.data.charid,
          //Android writing service
          //serviceId:'0000180d-0000-1000-8000-00805f9b34fb',
          //characteristicId:'00002a39-0000-1000-8000-00805f9b34fb',
          value: 'ABCD',
          success: res => {
            my.alert({ content: 'Succeeded to write data!' });
          },
          fail: error => {
            my.alert({ content: JSON.stringify(error) });
          },
        });
      },
    });
  },
  notifyBLECharacteristicValueChange() {
    my.getConnectedBluetoothDevices({
      success: res => {
        if (res.devices.length === 0) {
          my.alert({ content: 'No connected devices' });
          return;
        }
        this.setData({
          devid: res.devices[0].deviceId,
        });
        my.notifyBLECharacteristicValueChange({
          state: true,
          deviceId: this.data.devid,
          serviceId: this.data.serid,
          characteristicId: this.data.notifyId,
          success: () => {
            //Listens to characteristic change events 
            my.onBLECharacteristicValueChange({
              success: res => {
                //  my.alert({content: 'Changes of characteristics：'+JSON.stringify(res)});
                my.alert({ content: 'Obtain the response data = ' + res.value });
              },
            });
            my.alert({ content: 'Succeeded to listen' });
          },
          fail: error => {
            my.alert({ content: 'Failed to listen' + JSON.stringify(error) });
          },
        });
      },
    });
  },
  offBLECharacteristicValueChange() {
    my.offBLECharacteristicValueChange();
  },

  //Other events
  bluetoothAdapterStateChange() {
    my.onBluetoothAdapterStateChange(this.getBind('onBluetoothAdapterStateChange'));
  },
  onBluetoothAdapterStateChange() {
    if (res.error) {
      my.alert({ content: JSON.stringify(error) });
    } else {
      my.alert({ content: 'Changes of the Bluetooth state：' + JSON.stringify(res) });
    }
  },
  offBluetoothAdapterStateChange() {
    my.offBluetoothAdapterStateChange(this.getBind('onBluetoothAdapterStateChange'));
  },
  getBind(name) {
    if (!this[`bind${name}`]) {
      this[`bind${name}`] = this[name].bind(this);
    }
    return this[`bind${name}`];
  },
  BLEConnectionStateChanged() {
    my.onBLEConnectionStateChanged(this.getBind('onBLEConnectionStateChanged'));
  },
  onBLEConnectionStateChanged(res) {
    if (res.error) {
      my.alert({ content: JSON.stringify(error) });
    } else {
      my.alert({ content: 'Changes of connection state：' + JSON.stringify(res) });
    }
  },
  offBLEConnectionStateChanged() {
    my.offBLEConnectionStateChanged(this.getBind('onBLEConnectionStateChanged'));
  },
  onUnload() {
    this.offBLEConnectionStateChanged();
    this.offBLECharacteristicValueChange();
    this.offBluetoothAdapterStateChange();
    this.closeBluetoothAdapter();
  },
});

Parameters

he input parameters are displayed in the following table:

Property	Type	Required	Description
services	Array	No	UUID list of the service in the bluetooth device.
allowDuplicatesKey	Boolean	No	Determines whether to allow for duplicate keys. If yes, the API my.onBluetoothDeviceFound will report for this device, with different RSSI values.
interval	Integer	No	By default, the interval is 0, which means once a new device is found, the device will be reported; otherwise, the reporting frequency is the interval value.
success	Function	No	The callback function for a successful API call.
fail	Function	No	The callback function for a failed API call.
complete	Function	No	The callback function for a completed API call (regardless of whether the call is successful or not).