Issue with large data transmission about react-native-ble-manager HOT 13 CLOSED

Code

import {
  View,
  Text,
  TouchableOpacity,
  Platform,
  FlatList,
  Dimensions,
  NativeEventEmitter,
  NativeModules,
  SafeAreaView,
} from "react-native";
import {
  PERMISSIONS,
  RESULTS,
  checkMultiple,
  requestMultiple,
} from "react-native-permissions";
import React, {useState, useEffect, useCallback} from "react";
import BleManager from "react-native-ble-manager";
import {shallowEqual, useDispatch, useSelector} from "react-redux";
import {Buffer} from "buffer";

import styles from "./style";
import TopBar from "../../components/TopBar";
import { addTempData, addUpdateItem, selectorConnectedDevices, selectorDeviceConnected, updateScanningStatus, updateSensorData, updatedBluetoothStatus } from "../../redux/slices/deviceSlice";
import SectionHeading from "../../components/SectionHeading";
import { useFocusEffect } from "@react-navigation/native";

const {height} = Dimensions.get("window");
const navHeight = Platform.OS === "android" ? 55 : 85;
const screenArea = height - navHeight;

const BleManagerModule = NativeModules.BleManager;
const bleManagerEmitter = new NativeEventEmitter(BleManagerModule);

const serviceUUIDList = ["8de5e532-7565-4c8b-b333-5866350be21f"];

const ListBluetoothDevices = () => {

  const dispatch = useDispatch()
  
  const deviceState = useSelector(state => state.device);

  const discoveredDevices = selectorConnectedDevices(deviceState);
  const isDeviceConnected = selectorDeviceConnected(deviceState);

  // console.log('---isDeviceConnected---- :', isDeviceConnected)

  const isScanning = useSelector(
    state => state.device.scanningDevices === true,
  );

  const checkDeviceBlePermissions = async () => {
    return new Promise(async (resolve, reject) => {
      console.log("checking permissions");
      try {
        if (Platform.OS === "android") {
          const permissionsList = [
            PERMISSIONS.ANDROID.BLUETOOTH_SCAN,
            PERMISSIONS.ANDROID.BLUETOOTH_ADVERTISE,
            PERMISSIONS.ANDROID.BLUETOOTH_CONNECT,
          ];
          const permissions = await checkMultiple(permissionsList);
          const requestPermission = Object.keys(permissions).filter(
            el =>
              permissions[el] !== RESULTS.UNAVAILABLE &&
              permissions[el] !== RESULTS.GRANTED &&
              permissions[el] !== RESULTS.LIMITED,
          );
          if (requestPermission.length > 0) {
            const requestPermissionsResponse = await requestMultiple(
              requestPermission,
            );
            const requestPermissionRejected = Object.keys(
              requestPermissionsResponse,
            ).filter(el => requestPermissionsResponse[el] !== RESULTS.GRANTED);
            if (requestPermissionRejected.length > 0) {
              const errorMessage = `Please go to application settings and allow all required permission. Please share below information with developer. Version: ${Platform.Version}, OS: ${Platform.OS}, Release: ${Platform.constants.Release}`
              alert(errorMessage);
              reject(errorMessage)
            }
          }
          resolve(true)
        } else {
          const permissions = await checkMultiple([PERMISSIONS.IOS.BLUETOOTH]);
          const requestPermission = Object.keys(permissions).filter(
            el =>
              permissions[el] !== RESULTS.UNAVAILABLE &&
              permissions[el] !== RESULTS.GRANTED &&
              permissions[el] !== RESULTS.LIMITED,
          );
          if (requestPermission.length > 0) {
            const requestPermissionsResponse = await requestMultiple(
              requestPermission,
            );
            const requestPermissionRejected = Object.keys(
              requestPermissionsResponse,
            ).filter(el => requestPermissionsResponse[el] !== RESULTS.GRANTED);
            if (requestPermissionRejected.length > 0) {
              const errorMessage = `Please allow bluetooth and location permission. Please share below information with developer. Platform: IOS, Version: OS: ${
                Platform.OS
              }, Version: ${Platform.constants.osVersion}, System ${
                Platform.constants.systemName
              }, ${JSON.stringify(requestPermissionRejected)}`
              alert(errorMessage);
              reject(errorMessage)
            }
          }
          resolve(true)
        }
      } catch(e) {
        console.log('Permission issue. ', e)
        reject(e)
      }
    })
  }

  useEffect(() => {
    BleManager.start({
      showAlert: false,
    }).then(async () => {
      console.log('ble working well')
      try {
        const permissionEnabled = await checkDeviceBlePermissions()
        if (permissionEnabled) {
          const bluetoothEnabled = await isDeviceBluetoothWorking()
          if (!bluetoothEnabled) {
            if (Platform.OS === 'android') {
              enableAndroidBluetooth()
              .then(() => {
                dispatch(updatedBluetoothStatus(true));
              }).catch((e) => {
                console.log('enable bluetooth issue. ', e)
                dispatch(updatedBluetoothStatus(false));
              })
            } else {
              // alert('Please enable bluetooth.')
              dispatch(updatedBluetoothStatus(true));
              return false
            }
          }
        }
      } catch(e) {
        console.log('issue ---- ', e)
      }
    }).catch((e) => {
      console.log('ble manager issue', e)
    })
  }, [])

  const identifyReceivingData = data => {
    try {
      let type = "no_data";
      const first_bit = data && data.length > 0 ? data[0]: null;

      if (data.length === 2 && first_bit === 1 && data[1] === 1) {
        type = "heartbeat";
      } else if (data.length === 2 && first_bit === 34 && data[1] === 34) {
        type = "stop_collect_sensor_data";
      } else if (data.length === 2 && first_bit === 17 && data[1] === 17) {
        type = "start_collect_sensor_data";
      } else if (data.length === 3 && first_bit === 0) {
        type = "sensor_data_information";
      } else if (data.length === 3 && first_bit === 1) {
        type = "date_time_data_information";
      } else if (data.length === 3 && first_bit === 2) {
        type = "battery_data_information";
      } else if (data.length === 8) {
        type = "time_information";
      } else if (data.length > 8) {
        type = "sensor_data";
      }
      return type;
    } catch(e) {
      console.log('----issue----- ', e)
      return 'no_data'
    }
  };

  useEffect(() => {
    console.log('--- added listeners----')
    let stopUpdateBleListeners = bleManagerEmitter.addListener(
      "BleManagerDidUpdateState",
      args => {
        console.log("BleManagerDidUpdateState : ", args);
      },
    );

    let stopDiscoverListener = bleManagerEmitter.addListener(
      "BleManagerDiscoverPeripheral",
      peripheral => {
        if (Object.keys(peripheral).indexOf('name') > -1 && Object.keys(peripheral).indexOf('advertising') > -1 && peripheral.name) {
          const currentDate = new Date()
          dispatch(addUpdateItem({...peripheral, lastActivityTime: currentDate.getTime()}))
        }
      },
    )

    let stopConnectListener = bleManagerEmitter.addListener(
      "BleManagerConnectPeripheral",
      peripheral => {
        console.log(
          "BleManagerConnectPeripheral:",
          JSON.stringify(peripheral),
        );
      },
    )

    let stopScanListener = bleManagerEmitter.addListener(
      "BleManagerStopScan",
      () => {
        dispatch(updateScanningStatus(false));
        console.log("scan stopped");
      },
    );

    let stopDisconnectListener = bleManagerEmitter.addListener(
      "BleManagerDisconnectPeripheral",
      (event) => {
        console.debug(
          `[handleDisconnectedPeripheral][${event.peripheral}] disconnected.`,
        );
      }
    );

    let receiveDataListener = bleManagerEmitter.addListener(
      "BleManagerDidUpdateValueForCharacteristic",
      (args) => {
        // {value, peripheral, characteristic, service}
        try {
          // let rawData = [...value];
          // let typeOfData = identifyReceivingData(rawData);
          console.log("---START DEBUGGER--- :");
          // console.log({value, peripheral, characteristic, service});
          console.log(args);
          console.log("---END DEBUGGER--- : ");

          // heartbeat : For connection
          // if (typeOfData === "heartbeat") {
          //   // const timeStamp = new Date();
          //   // dispatch(
          //   //   updateConnectionState({
          //   //     deviceId: peripheral,
          //   //     lastUpdatedTime: timeStamp.getTime(),
          //   //   }),
          //   // );
          //   // send 0x01
          //   // setTimeout(() => {
          //   //   try {
          //   //     sendCommandToDevice(
          //   //       peripheral,
          //   //       singleServiceUID,
          //   //       writeCharacteristicUUID,
          //   //       "0x01, 0x01",
          //   //     );
          //   //   } catch (e) {
          //   //     console.log("====sendCommandToDevice issue=== :", e);
          //   //   }
          //   // }, 1000);
          // } else if (typeOfData === "sensor_data_information") {
          //   rawData.splice(0, 1);
          //   const total_data_length =
          //     parseFloat(parseFloat(rawData[0]) * 256) +
          //     parseFloat(rawData[1]);
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_total_count: parseFloat(total_data_length / 12),
          //     }),
          //   );
          // } else if (typeOfData === "date_time_data_information") {
          //   rawData.splice(0, 1);
          //   const total_data_length =
          //     parseFloat(parseFloat(rawData[0]) * 256) +
          //     parseFloat(rawData[1]);
          //   console.log("date_time_data_information", total_data_length);
          // } else if (typeOfData === "battery_data_information") {
          //   console.log("battery_data_information");
          // } else if (typeOfData === "time_information") {
          //   const monthValue =
          //     parseFloat(value[1]) < 10 ? `0${value[1]}` : value[1];
          //   const dateValue =
          //     parseFloat(value[2]) < 10 ? `0${value[2]}` : value[2];
          //   const miliSecond = parseFloat(`${value[6]}${value[7]}`);
          //   const information = `20${value[0]}-${monthValue}-${dateValue} ${value[3]}:${value[4]}:${value[5]}`;
          //   const date_time = new Date(information);
          //   date_time.setMilliseconds(miliSecond);
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_date: date_time
          //         .toISOString()
          //         .replace(/:/g, "")
          //         .replace(".", "+")
          //         .replace("Z", ""),
          //     }),
          //   );
          //   console.log(`${typeOfData} - ${date_time.toISOString()}`);
          // } else if (typeOfData === "sensor_data") {
          //   console.log('----sensor data -----')
          //   const allSensorData = [];
          //   for (let j = 0; j < rawData.length; j += 12) {
          //     const singleDataBuffer = rawData.slice(j, j + 12);
          //     const sensorData = {
          //       x_accel: 0,
          //       y_accel: 0,
          //       z_accel: 0,
          //       x_gyro: 0,
          //       y_gyro: 0,
          //       z_gyro: 0,
          //     };
          //     const parsedValues = [];
          //     for (let i = 0; i < singleDataBuffer.length; i += 2) {
          //       const parsingValue = singleDataBuffer.slice(i, i + 2);
          //       const sensorValue = parseFloat(parsingValue[1]);
          //       const signedValue = parseFloat(parsingValue[0]);
          //       let multipleFactor = 2000;
          //       if (i > 4) {
          //         multipleFactor = 20000;
          //       }
          //       const calculatedValue = Number(
          //         (
          //           (parseFloat(signedValue * 256) +
          //             parseFloat(sensorValue - multipleFactor)) /
          //           10
          //         ).toPrecision(3),
          //       );
          //       parsedValues.push(
          //         !isNaN(calculatedValue) ? calculatedValue : 0,
          //       );
          //     }

          //     const propertiesKeys = Object.keys(sensorData);
          //     for (let i = 0; i < propertiesKeys.length; i++) {
          //       sensorData[propertiesKeys[i]] =
          //         typeof parsedValues[i] != "undefined" ? parsedValues[i] : 0;
          //     }

          //     allSensorData.push(sensorData);
          //   }

          //   console.log("----data saving----- : ");
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_data: allSensorData,
          //     }),
          //   );
          // } else if (typeOfData === "start_collect_sensor_data") {
          //   console.log("---start_collect_sensor_data----");
          // } else if (typeOfData === "stop_collect_sensor_data") {
          //   console.log("End Notification : ");
          //   console.log("writing now ------ :: ");
          //   dispatch(
          //     updateSensorData({
          //       deviceId: peripheral,
          //     }),
          //   );
          //   BleManager.disconnect(peripheral)
          //   .then(() => {
          //     console.log('----successfully disconnected-----')
          //   })
          //   .catch((e) => {
          //     console.log('--subscriber event issue--- disconnect--- :', e)
          //   })
          // }
        } catch(e) {
          console.log("---ISSUE WITH DATA PARSING---");
          console.log(e);
          console.log("---ISSUE WITH DATA PARSING---");
        }
        return true
      },
    )
    return () => {
      console.log('------unsubscribe-----')
      stopDiscoverListener.remove();
      stopConnectListener.remove();
      stopScanListener.remove();
      receiveDataListener.remove();
      stopUpdateBleListeners.remove();
      stopDisconnectListener.remove();
    };
  }, [])

  useFocusEffect(useCallback(() => {
    const initialCheckup = async () => {
      try {
        const permissionEnabled = await checkDeviceBlePermissions()
        if (permissionEnabled) {
          const bluetoothEnabled = await isDeviceBluetoothWorking()
          if (!bluetoothEnabled) {
            if (Platform.OS === 'android') {
              enableAndroidBluetooth()
              .then(() => {
                dispatch(updatedBluetoothStatus(true));
              }).catch((e) => {
                console.log('enable bluetooth issue. ', e)
                dispatch(updatedBluetoothStatus(false));
              })
            } else {
              alert('Please enable bluetooth.')
              dispatch(updatedBluetoothStatus(true));
              return false
            }
          }
        }
      } catch(e) {
        console.log('issue ---- ', e)
      }
    }
    initialCheckup();
  }, []))

  const enableAndroidBluetooth = () => {
    return new Promise(async (resolve, reject) => {
      try {
        await BleManager.enableBluetooth();
        resolve(true)
      } catch(e) {
        reject(e)
      }
    })
  }

  const isDeviceBluetoothWorking = () => {
    return BleManager.checkState()
      .then((state) => {
        console.log('device bluetooth state : ', state)
        if (state === 'on') {
          return true;
        }
        return false
      })
      .catch((e) => {
        console.log('device bluetooth state issue : ', e)
        return false;
      })
  }

  const toggleScan = async (scanningNow) => {
    // if scanning stop scanning
    console.log('ScanningStatus : ', scanningNow)
    try {
      const bluetoothEnabled = await isDeviceBluetoothWorking()
      if (!bluetoothEnabled) {
        alert('Please enable bluetooth and try again')
        if (scanningNow) {
          dispatch(updateScanningStatus(false));
        }
        return false
      }
      // check if scanning now
      if (!scanningNow) {
        try {
          await BleManager.scan(serviceUUIDList, -1, true)
          dispatch(updateScanningStatus(true));
        } catch(scanningError) {
          console.log('Issue in scanning. ', scanningError)
          dispatch(updateScanningStatus(false));
        }
      } else {
        try {
          await BleManager.stopScan();
        } catch(stopScanningError) {
          console.log('Issue in stop scanning. ', stopScanningError)
        }
      }
    } catch(e) {
      console.log('---scanning issue----', e)
    }
  }

  const RenderBleDeviceLists = ({peripheral}) => {
    const {name, id } = peripheral;
    return (
      <>
        {name && (
          <View style={styles.bleListMainView}>
            <View style={{flex: 1}}>
              <Text style={styles.bleListNameText}>{name}</Text>
              <Text style={styles.bleListIdText}>ID: {id}</Text>
            </View>
          </View>
        )}
      </>
    );
  };

  return (
    <View style={styles.mainView}>
      <TopBar deviceConnected={isDeviceConnected} />
      <View style={styles.contentView}>
        <View style={styles.headingTextContainer}>
          <Text style={styles.headingText}>Devices</Text>
        </View>
        <TouchableOpacity
          onPress={() => toggleScan(isScanning)}
          style={styles.scanButton}>
          <Text style={styles.scanButtonText}>
            {isScanning ? "Stop Scanning" : "Scan Devices"}
          </Text>
        </TouchableOpacity>
        <View style={{marginTop: 20}}>
          <SectionHeading
            title="All Devices"
            countTitle="discovered"
            count={discoveredDevices ? discoveredDevices.length : 0}
          />
          {discoveredDevices && discoveredDevices.length > 0 ? (
            <SafeAreaView>
              <FlatList
                style={{maxHeight: screenArea * 0.27}}
                data={discoveredDevices}
                renderItem={({item}) => (
                  <RenderBleDeviceLists
                    peripheral={item}
                  />
                )}
                keyExtractor={item => `${item.id}_discovered`}
              />
            </SafeAreaView>
          ) : (
            <Text style={{color: "#000", paddingHorizontal: 2}}>
              {isScanning
                ? "Scanning for devices ... "
                : "No Device Discovered"}
            </Text>
          )}
        </View>
      </View>
    </View>
  )
}

export default ListBluetoothDevices

from react-native-ble-manager.

After requestMTU the data was received. But it suppose to receive data without requestMTU.

from react-native-ble-manager.

Is not a bug, is how BLE is designed in the OS

from react-native-ble-manager.

Every time we need to call requestMTU while receive data? @marcosinigaglia

from react-native-ble-manager.

The default MTU on Android is 20, so after connecting it should be set to the size you need.

from react-native-ble-manager.

And what is the maximum MTU we can set? I set it to 1000 and it never return any thing.

from react-native-ble-manager.

@marcosinigaglia I am receiving 160 values in one transmission. It will transmit 2560 values total. Then what to set MTU and what will be approach ?

from react-native-ble-manager.

@marcosinigaglia I hope this information will help

06-06 00:40:03.941 941 22637 D r_submix: read_frames 21813390336, T_rec 454445.656250s, p_vs_o 15209us 06-06 00:40:04.004 942 965 D [email protected]: BtHostDebugInfo 06-06 00:40:04.004 942 965 D [BT] : mtk_bt_op: BT_VND_OP_SET_BTHOST 06-06 00:40:04.008 2096 2555 I bt_stack: [INFO:btsnoop.cc(342)] clear_l2cap_allowlist: Clearing acceptlist from l2cap channel. conn_handle=512 cid=4:4 06-06 00:40:04.009 2096 2555 I bt_stack: [INFO:gatt_attr.cc(338)] gatt_connect_cback: remove untrusted client status, bda=e7:01:a9:03:d3:8c 06-06 00:40:04.009 2096 2555 I bluetooth: system/bt/stack/gap/gap_ble.cc:298 client_connect_cback: No active GAP service found for peer:xx:xx:xx:xx:d3:8c callback:Disconnected 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:3 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:4 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:5 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:6 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:7 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.011 2096 2555 I bt_bta_gattc: system/bt/bta/gatt/bta_gattc_act.cc:1148 bta_gattc_conn_cback: Disconnected att_id:8 transport:le reason:GATT_CONN_TIMEOUT 06-06 00:40:04.012 2096 2555 W bt_btm_sec: system/bt/stack/btm/btm_sec.cc:3849 btm_sec_disconnected: Got uncommon disconnection reason:Connection Timeout handle:0x0200 06-06 00:40:04.012 2096 2555 I btif_av : system/bt/btif/src/btif_av.cc:4184 btif_av_get_peer_sep: No active sink or source peer found 06-06 00:40:04.012 2096 2555 I bt_btif_a2dp_source: system/bt/btif/src/btif_a2dp_source.cc:850 btif_a2dp_source_on_idle: btif_a2dp_source_on_idle: state=STATE_OFF 06-06 00:40:04.012 2096 2555 I btif_av : system/bt/btif/src/btif_av.cc:4184 btif_av_get_peer_sep: No active sink or source peer found 06-06 00:40:04.012 2096 2555 I bt_btif_a2dp_source: system/bt/btif/src/btif_a2dp_source.cc:850 btif_a2dp_source_on_idle: btif_a2dp_source_on_idle: state=STATE_OFF 06-06 00:40:04.012 942 965 D [email protected]: BtHostDebugInfo 06-06 00:40:04.012 942 965 D [BT] : mtk_bt_op: BT_VND_OP_SET_BTHOST 06-06 00:40:04.015 2096 31976 D BluetoothMetrics: btclass1f00 06-06 00:40:04.015 27885 27925 D BluetoothGatt: onClientConnectionState() - status=0 clientIf=8 device=E7:01:A9:03:D3:8C 06-06 00:40:04.016 942 965 D [email protected]: BtHostDebugInfo 06-06 00:40:04.016 942 965 D [BT] : mtk_bt_op: BT_VND_OP_SET_BTHOST 06-06 00:40:04.016 27885 27925 D RNBleManager: onConnectionStateChange to 0 on peripheral: E7:01:A9:03:D3:8C with status 0 06-06 00:40:04.018 2096 31976 D Checkin : publish the event [tag = MOT_BT event name = DISC] 06-06 00:40:04.020 27885 27885 D BluetoothGatt: cancelOpen() - device: E7:01:A9:03:D3:8C 06-06 00:40:04.024 27885 27885 D BluetoothGatt: close() 06-06 00:40:04.024 27885 27885 D BluetoothGatt: unregisterApp() - mClientIf=8 06-06 00:40:04.034 27885 27885 D RNBleManager: Peripheral event (BleManagerDisconnectPeripheral):E7:01:A9:03:D3:8C 06-06 00:40:04.035 2128 2223 W BluetoothEventManager: AclStateChangedHandler: activeDevice is null

from react-native-ble-manager.

The device disconnects on BLE_GATT_STATUS_SUCCESS 0x0000. code

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.s132.api.v3.0.0%2Fgroup___b_l_e___g_a_t_t___s_t_a_t_u_s___c_o_d_e_s.html

from react-native-ble-manager.

Code

import {
  View,
  Text,
  TouchableOpacity,
  Platform,
  FlatList,
  Dimensions,
  NativeEventEmitter,
  NativeModules,
  SafeAreaView,
} from "react-native";
import {
  PERMISSIONS,
  RESULTS,
  checkMultiple,
  requestMultiple,
} from "react-native-permissions";
import React, {useState, useEffect, useCallback} from "react";
import BleManager from "react-native-ble-manager";
import {shallowEqual, useDispatch, useSelector} from "react-redux";
import {Buffer} from "buffer";

import styles from "./style";
import TopBar from "../../components/TopBar";
import { addTempData, addUpdateItem, selectorConnectedDevices, selectorDeviceConnected, updateScanningStatus, updateSensorData, updatedBluetoothStatus } from "../../redux/slices/deviceSlice";
import SectionHeading from "../../components/SectionHeading";
import { useFocusEffect } from "@react-navigation/native";

const {height} = Dimensions.get("window");
const navHeight = Platform.OS === "android" ? 55 : 85;
const screenArea = height - navHeight;

const BleManagerModule = NativeModules.BleManager;
const bleManagerEmitter = new NativeEventEmitter(BleManagerModule);

const serviceUUIDList = ["8de5e532-7565-4c8b-b333-5866350be21f"];

const ListBluetoothDevices = () => {

  const dispatch = useDispatch()
  
  const deviceState = useSelector(state => state.device);

  const discoveredDevices = selectorConnectedDevices(deviceState);
  const isDeviceConnected = selectorDeviceConnected(deviceState);

  // console.log('---isDeviceConnected---- :', isDeviceConnected)

  const isScanning = useSelector(
    state => state.device.scanningDevices === true,
  );

  const checkDeviceBlePermissions = async () => {
    return new Promise(async (resolve, reject) => {
      console.log("checking permissions");
      try {
        if (Platform.OS === "android") {
          const permissionsList = [
            PERMISSIONS.ANDROID.BLUETOOTH_SCAN,
            PERMISSIONS.ANDROID.BLUETOOTH_ADVERTISE,
            PERMISSIONS.ANDROID.BLUETOOTH_CONNECT,
          ];
          const permissions = await checkMultiple(permissionsList);
          const requestPermission = Object.keys(permissions).filter(
            el =>
              permissions[el] !== RESULTS.UNAVAILABLE &&
              permissions[el] !== RESULTS.GRANTED &&
              permissions[el] !== RESULTS.LIMITED,
          );
          if (requestPermission.length > 0) {
            const requestPermissionsResponse = await requestMultiple(
              requestPermission,
            );
            const requestPermissionRejected = Object.keys(
              requestPermissionsResponse,
            ).filter(el => requestPermissionsResponse[el] !== RESULTS.GRANTED);
            if (requestPermissionRejected.length > 0) {
              const errorMessage = `Please go to application settings and allow all required permission. Please share below information with developer. Version: ${Platform.Version}, OS: ${Platform.OS}, Release: ${Platform.constants.Release}`
              alert(errorMessage);
              reject(errorMessage)
            }
          }
          resolve(true)
        } else {
          const permissions = await checkMultiple([PERMISSIONS.IOS.BLUETOOTH]);
          const requestPermission = Object.keys(permissions).filter(
            el =>
              permissions[el] !== RESULTS.UNAVAILABLE &&
              permissions[el] !== RESULTS.GRANTED &&
              permissions[el] !== RESULTS.LIMITED,
          );
          if (requestPermission.length > 0) {
            const requestPermissionsResponse = await requestMultiple(
              requestPermission,
            );
            const requestPermissionRejected = Object.keys(
              requestPermissionsResponse,
            ).filter(el => requestPermissionsResponse[el] !== RESULTS.GRANTED);
            if (requestPermissionRejected.length > 0) {
              const errorMessage = `Please allow bluetooth and location permission. Please share below information with developer. Platform: IOS, Version: OS: ${
                Platform.OS
              }, Version: ${Platform.constants.osVersion}, System ${
                Platform.constants.systemName
              }, ${JSON.stringify(requestPermissionRejected)}`
              alert(errorMessage);
              reject(errorMessage)
            }
          }
          resolve(true)
        }
      } catch(e) {
        console.log('Permission issue. ', e)
        reject(e)
      }
    })
  }

  useEffect(() => {
    BleManager.start({
      showAlert: false,
    }).then(async () => {
      console.log('ble working well')
      try {
        const permissionEnabled = await checkDeviceBlePermissions()
        if (permissionEnabled) {
          const bluetoothEnabled = await isDeviceBluetoothWorking()
          if (!bluetoothEnabled) {
            if (Platform.OS === 'android') {
              enableAndroidBluetooth()
              .then(() => {
                dispatch(updatedBluetoothStatus(true));
              }).catch((e) => {
                console.log('enable bluetooth issue. ', e)
                dispatch(updatedBluetoothStatus(false));
              })
            } else {
              // alert('Please enable bluetooth.')
              dispatch(updatedBluetoothStatus(true));
              return false
            }
          }
        }
      } catch(e) {
        console.log('issue ---- ', e)
      }
    }).catch((e) => {
      console.log('ble manager issue', e)
    })
  }, [])

  const identifyReceivingData = data => {
    try {
      let type = "no_data";
      const first_bit = data && data.length > 0 ? data[0]: null;

      if (data.length === 2 && first_bit === 1 && data[1] === 1) {
        type = "heartbeat";
      } else if (data.length === 2 && first_bit === 34 && data[1] === 34) {
        type = "stop_collect_sensor_data";
      } else if (data.length === 2 && first_bit === 17 && data[1] === 17) {
        type = "start_collect_sensor_data";
      } else if (data.length === 3 && first_bit === 0) {
        type = "sensor_data_information";
      } else if (data.length === 3 && first_bit === 1) {
        type = "date_time_data_information";
      } else if (data.length === 3 && first_bit === 2) {
        type = "battery_data_information";
      } else if (data.length === 8) {
        type = "time_information";
      } else if (data.length > 8) {
        type = "sensor_data";
      }
      return type;
    } catch(e) {
      console.log('----issue----- ', e)
      return 'no_data'
    }
  };

  useEffect(() => {
    console.log('--- added listeners----')
    let stopUpdateBleListeners = bleManagerEmitter.addListener(
      "BleManagerDidUpdateState",
      args => {
        console.log("BleManagerDidUpdateState : ", args);
      },
    );

    let stopDiscoverListener = bleManagerEmitter.addListener(
      "BleManagerDiscoverPeripheral",
      peripheral => {
        if (Object.keys(peripheral).indexOf('name') > -1 && Object.keys(peripheral).indexOf('advertising') > -1 && peripheral.name) {
          const currentDate = new Date()
          dispatch(addUpdateItem({...peripheral, lastActivityTime: currentDate.getTime()}))
        }
      },
    )

    let stopConnectListener = bleManagerEmitter.addListener(
      "BleManagerConnectPeripheral",
      peripheral => {
        console.log(
          "BleManagerConnectPeripheral:",
          JSON.stringify(peripheral),
        );
      },
    )

    let stopScanListener = bleManagerEmitter.addListener(
      "BleManagerStopScan",
      () => {
        dispatch(updateScanningStatus(false));
        console.log("scan stopped");
      },
    );

    let stopDisconnectListener = bleManagerEmitter.addListener(
      "BleManagerDisconnectPeripheral",
      (event) => {
        console.debug(
          `[handleDisconnectedPeripheral][${event.peripheral}] disconnected.`,
        );
      }
    );

    let receiveDataListener = bleManagerEmitter.addListener(
      "BleManagerDidUpdateValueForCharacteristic",
      (args) => {
        // {value, peripheral, characteristic, service}
        try {
          // let rawData = [...value];
          // let typeOfData = identifyReceivingData(rawData);
          console.log("---START DEBUGGER--- :");
          // console.log({value, peripheral, characteristic, service});
          console.log(args);
          console.log("---END DEBUGGER--- : ");

          // heartbeat : For connection
          // if (typeOfData === "heartbeat") {
          //   // const timeStamp = new Date();
          //   // dispatch(
          //   //   updateConnectionState({
          //   //     deviceId: peripheral,
          //   //     lastUpdatedTime: timeStamp.getTime(),
          //   //   }),
          //   // );
          //   // send 0x01
          //   // setTimeout(() => {
          //   //   try {
          //   //     sendCommandToDevice(
          //   //       peripheral,
          //   //       singleServiceUID,
          //   //       writeCharacteristicUUID,
          //   //       "0x01, 0x01",
          //   //     );
          //   //   } catch (e) {
          //   //     console.log("====sendCommandToDevice issue=== :", e);
          //   //   }
          //   // }, 1000);
          // } else if (typeOfData === "sensor_data_information") {
          //   rawData.splice(0, 1);
          //   const total_data_length =
          //     parseFloat(parseFloat(rawData[0]) * 256) +
          //     parseFloat(rawData[1]);
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_total_count: parseFloat(total_data_length / 12),
          //     }),
          //   );
          // } else if (typeOfData === "date_time_data_information") {
          //   rawData.splice(0, 1);
          //   const total_data_length =
          //     parseFloat(parseFloat(rawData[0]) * 256) +
          //     parseFloat(rawData[1]);
          //   console.log("date_time_data_information", total_data_length);
          // } else if (typeOfData === "battery_data_information") {
          //   console.log("battery_data_information");
          // } else if (typeOfData === "time_information") {
          //   const monthValue =
          //     parseFloat(value[1]) < 10 ? `0${value[1]}` : value[1];
          //   const dateValue =
          //     parseFloat(value[2]) < 10 ? `0${value[2]}` : value[2];
          //   const miliSecond = parseFloat(`${value[6]}${value[7]}`);
          //   const information = `20${value[0]}-${monthValue}-${dateValue} ${value[3]}:${value[4]}:${value[5]}`;
          //   const date_time = new Date(information);
          //   date_time.setMilliseconds(miliSecond);
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_date: date_time
          //         .toISOString()
          //         .replace(/:/g, "")
          //         .replace(".", "+")
          //         .replace("Z", ""),
          //     }),
          //   );
          //   console.log(`${typeOfData} - ${date_time.toISOString()}`);
          // } else if (typeOfData === "sensor_data") {
          //   console.log('----sensor data -----')
          //   const allSensorData = [];
          //   for (let j = 0; j < rawData.length; j += 12) {
          //     const singleDataBuffer = rawData.slice(j, j + 12);
          //     const sensorData = {
          //       x_accel: 0,
          //       y_accel: 0,
          //       z_accel: 0,
          //       x_gyro: 0,
          //       y_gyro: 0,
          //       z_gyro: 0,
          //     };
          //     const parsedValues = [];
          //     for (let i = 0; i < singleDataBuffer.length; i += 2) {
          //       const parsingValue = singleDataBuffer.slice(i, i + 2);
          //       const sensorValue = parseFloat(parsingValue[1]);
          //       const signedValue = parseFloat(parsingValue[0]);
          //       let multipleFactor = 2000;
          //       if (i > 4) {
          //         multipleFactor = 20000;
          //       }
          //       const calculatedValue = Number(
          //         (
          //           (parseFloat(signedValue * 256) +
          //             parseFloat(sensorValue - multipleFactor)) /
          //           10
          //         ).toPrecision(3),
          //       );
          //       parsedValues.push(
          //         !isNaN(calculatedValue) ? calculatedValue : 0,
          //       );
          //     }

          //     const propertiesKeys = Object.keys(sensorData);
          //     for (let i = 0; i < propertiesKeys.length; i++) {
          //       sensorData[propertiesKeys[i]] =
          //         typeof parsedValues[i] != "undefined" ? parsedValues[i] : 0;
          //     }

          //     allSensorData.push(sensorData);
          //   }

          //   console.log("----data saving----- : ");
          //   dispatch(
          //     addTempData({
          //       deviceId: peripheral,
          //       impact_data: allSensorData,
          //     }),
          //   );
          // } else if (typeOfData === "start_collect_sensor_data") {
          //   console.log("---start_collect_sensor_data----");
          // } else if (typeOfData === "stop_collect_sensor_data") {
          //   console.log("End Notification : ");
          //   console.log("writing now ------ :: ");
          //   dispatch(
          //     updateSensorData({
          //       deviceId: peripheral,
          //     }),
          //   );
          //   BleManager.disconnect(peripheral)
          //   .then(() => {
          //     console.log('----successfully disconnected-----')
          //   })
          //   .catch((e) => {
          //     console.log('--subscriber event issue--- disconnect--- :', e)
          //   })
          // }
        } catch(e) {
          console.log("---ISSUE WITH DATA PARSING---");
          console.log(e);
          console.log("---ISSUE WITH DATA PARSING---");
        }
        return true
      },
    )
    return () => {
      console.log('------unsubscribe-----')
      stopDiscoverListener.remove();
      stopConnectListener.remove();
      stopScanListener.remove();
      receiveDataListener.remove();
      stopUpdateBleListeners.remove();
      stopDisconnectListener.remove();
    };
  }, [])

  useFocusEffect(useCallback(() => {
    const initialCheckup = async () => {
      try {
        const permissionEnabled = await checkDeviceBlePermissions()
        if (permissionEnabled) {
          const bluetoothEnabled = await isDeviceBluetoothWorking()
          if (!bluetoothEnabled) {
            if (Platform.OS === 'android') {
              enableAndroidBluetooth()
              .then(() => {
                dispatch(updatedBluetoothStatus(true));
              }).catch((e) => {
                console.log('enable bluetooth issue. ', e)
                dispatch(updatedBluetoothStatus(false));
              })
            } else {
              alert('Please enable bluetooth.')
              dispatch(updatedBluetoothStatus(true));
              return false
            }
          }
        }
      } catch(e) {
        console.log('issue ---- ', e)
      }
    }
    initialCheckup();
  }, []))

  const enableAndroidBluetooth = () => {
    return new Promise(async (resolve, reject) => {
      try {
        await BleManager.enableBluetooth();
        resolve(true)
      } catch(e) {
        reject(e)
      }
    })
  }

  const isDeviceBluetoothWorking = () => {
    return BleManager.checkState()
      .then((state) => {
        console.log('device bluetooth state : ', state)
        if (state === 'on') {
          return true;
        }
        return false
      })
      .catch((e) => {
        console.log('device bluetooth state issue : ', e)
        return false;
      })
  }

  const toggleScan = async (scanningNow) => {
    // if scanning stop scanning
    console.log('ScanningStatus : ', scanningNow)
    try {
      const bluetoothEnabled = await isDeviceBluetoothWorking()
      if (!bluetoothEnabled) {
        alert('Please enable bluetooth and try again')
        if (scanningNow) {
          dispatch(updateScanningStatus(false));
        }
        return false
      }
      // check if scanning now
      if (!scanningNow) {
        try {
          await BleManager.scan(serviceUUIDList, -1, true)
          dispatch(updateScanningStatus(true));
        } catch(scanningError) {
          console.log('Issue in scanning. ', scanningError)
          dispatch(updateScanningStatus(false));
        }
      } else {
        try {
          await BleManager.stopScan();
        } catch(stopScanningError) {
          console.log('Issue in stop scanning. ', stopScanningError)
        }
      }
    } catch(e) {
      console.log('---scanning issue----', e)
    }
  }

  const RenderBleDeviceLists = ({peripheral}) => {
    const {name, id } = peripheral;
    return (
      <>
        {name && (
          <View style={styles.bleListMainView}>
            <View style={{flex: 1}}>
              <Text style={styles.bleListNameText}>{name}</Text>
              <Text style={styles.bleListIdText}>ID: {id}</Text>
            </View>
          </View>
        )}
      </>
    );
  };

  return (
    <View style={styles.mainView}>
      <TopBar deviceConnected={isDeviceConnected} />
      <View style={styles.contentView}>
        <View style={styles.headingTextContainer}>
          <Text style={styles.headingText}>Devices</Text>
        </View>
        <TouchableOpacity
          onPress={() => toggleScan(isScanning)}
          style={styles.scanButton}>
          <Text style={styles.scanButtonText}>
            {isScanning ? "Stop Scanning" : "Scan Devices"}
          </Text>
        </TouchableOpacity>
        <View style={{marginTop: 20}}>
          <SectionHeading
            title="All Devices"
            countTitle="discovered"
            count={discoveredDevices ? discoveredDevices.length : 0}
          />
          {discoveredDevices && discoveredDevices.length > 0 ? (
            <SafeAreaView>
              <FlatList
                style={{maxHeight: screenArea * 0.27}}
                data={discoveredDevices}
                renderItem={({item}) => (
                  <RenderBleDeviceLists
                    peripheral={item}
                  />
                )}
                keyExtractor={item => `${item.id}_discovered`}
              />
            </SafeAreaView>
          ) : (
            <Text style={{color: "#000", paddingHorizontal: 2}}>
              {isScanning
                ? "Scanning for devices ... "
                : "No Device Discovered"}
            </Text>
          )}
        </View>
      </View>
    </View>
  )
}

export default ListBluetoothDevices

HI @varun761 I am not able get the values from this listener
BleManagerDidUpdateValueForCharacteristic, can you please help me how I can get data?

from react-native-ble-manager.

@itsaliraxa Yes sure. Add me to skype live:sharma.varun76.

from react-native-ble-manager.

Increasing the data transmission time can help you out. If it's 5s right now make it 10 seconds or more. Processing of data depends upon the mobile device.

from react-native-ble-manager.

from react-native-ble-manager.