@ohos.driver.deviceManager (Peripheral Management)

The deviceManager module provides APIs for managing peripheral devices, including querying the peripheral device list and binding or unbinding a peripheral device.

NOTE

The initial APIs of this module are supported since API version 10. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import deviceManager from "@ohos.driver.deviceManager";

deviceManager.queryDevices

queryDevices(busType?: number): Array<Readonly<Device>>

Queries the list of peripheral devices. If the device has no peripheral device connected, an empty list is returned.

Required permissions: ohos.permission.ACCESS_EXTENSIONAL_DEVICE_DRIVER

System capability: SystemCapability.Driver.ExternalDevice

Parameters

Name	Type	Mandatory	Description
busType	number	No	Bus type of the peripheral device. If this parameter is left blank, all types of peripheral devices are queried.

Return value

Type	Description
Array<Readonly<Device>>	List of peripheral devices obtained.

Error codes

ID	Error Message
401	The parameter check failed.
22900001	ExternalDeviceManager service exception.

Example

import deviceManager from "@ohos.driver.deviceManager";


try {
  let devices : Array<deviceManager.Device> = deviceManager.queryDevices(deviceManager.BusType.USB);
  for (let item of devices) {
    let device : deviceManager.USBDevice = item as deviceManager.USBDevice;
    console.info(`Device id is ${device.deviceId}`)
  }
} catch (error) {
  console.error(`Failed to query device. Code is ${error.code}, message is ${error.message}`);
}

deviceManager.bindDevice

bindDevice(deviceId: number, onDisconnect: AsyncCallback<number>, callback: AsyncCallback<{deviceId: number, remote: rpc.IRemoteObject}>): void;

Binds a peripheral device based on the device information returned by queryDevices(). This API uses an asynchronous callback to return the result.

You need to use deviceManager.queryDevices to obtain the peripheral device information first.

Required permissions: ohos.permission.ACCESS_EXTENSIONAL_DEVICE_DRIVER

System capability: SystemCapability.Driver.ExternalDevice

Parameters

Name	Type	Mandatory	Description
deviceId	number	Yes	ID of the device to bind. It can be obtained by queryDevices().
onDisconnect	AsyncCallback<number>	Yes	Callback to be invoked when the bound peripheral device is disconnected.
callback	AsyncCallback<{deviceId: number, remote: rpc.IRemoteObject}>	Yes	Callback invoked to return the communication object of the peripheral device bound.

Error codes

ID	Error Message
401	The parameter check failed.
22900001	ExternalDeviceManager service exception.

Example

import deviceManager from "@ohos.driver.deviceManager";
import { BusinessError } from '@ohos.base';

try {
  // For example, deviceId is 12345678. You can use queryDevices() to obtain the deviceId.
  deviceManager.bindDevice(12345678, (error : BusinessError, data : number) => {
    console.error(`Device is disconnected`);
  }, (error : BusinessError, data: {
      deviceId : number;
      remote : rpc.IRemoteObject;
  }) => {
    if (error) {
      console.error(`bindDevice async fail. Code is ${error.code}, message is ${error.message}`);
      return;
    }
    console.info(`bindDevice success`);
  });
} catch (error) {
  console.error(`bindDevice fail. Code is ${error.code}, message is ${error.message}`);
}

deviceManager.bindDevice

bindDevice(deviceId: number, onDisconnect: AsyncCallback<number>): Promise<{deviceId: number, remote: rpc.IRemoteObject}>;

Binds a peripheral device based on the device information returned by queryDevices(). This API uses a promise to return the result.

You need to use deviceManager.queryDevices to obtain the peripheral device information first.

Required permissions: ohos.permission.ACCESS_EXTENSIONAL_DEVICE_DRIVER

System capability: SystemCapability.Driver.ExternalDevice

Parameters

Name	Type	Mandatory	Description
deviceId	number	Yes	ID of the device to bind. It can be obtained by queryDevices().
onDisconnect	AsyncCallback<number>	Yes	Callback to be invoked when the bound peripheral device is disconnected.

Return value

Type	Description
Promise<{deviceId: number, remote: rpc.IRemoteObject}>	Promise used to return the device ID and IRemoteObject object.

Error codes

ID	Error Message
401	The parameter check failed.
22900001	ExternalDeviceManager service exception.

Example

import deviceManager from "@ohos.driver.deviceManager";
import { BusinessError } from '@ohos.base';

try {
  // For example, deviceId is 12345678. You can use queryDevices() to obtain the deviceId.
  deviceManager.bindDevice(12345678, (error : BusinessError, data : number) => {
    console.error(`Device is disconnected`);
  }).then(data => {
    console.info(`bindDevice success, Device_Id is ${data.deviceId}.
    remote is ${data.remote != null ? data.remote.getDescriptor() : "null"}`);
  }, (error: BusinessError) => {
    console.error(`bindDevice async fail. Code is ${error.code}, message is ${error.message}`);
  });
} catch (error) {
  console.error(`bindDevice fail. Code is ${error.code}, message is ${error.message}`);
}

deviceManager.unbindDevice

unbindDevice(deviceId: number, callback: AsyncCallback<number>): void

Unbinds a peripheral device. This API uses an asynchronous callback to return the result.

Required permissions: ohos.permission.ACCESS_EXTENSIONAL_DEVICE_DRIVER

System capability: SystemCapability.Driver.ExternalDevice

Parameters

Name	Type	Mandatory	Description
deviceId	number	Yes	ID of the device to unbind. It can be obtained by queryDevices().
callback	AsyncCallback<number>	Yes	Callback invoked to return the result.

Error codes

ID	Error Message
401	The parameter check failed.
22900001	ExternalDeviceManager service exception.

Example

import deviceManager from "@ohos.driver.deviceManager";

try {
  // For example, deviceId is 12345678. You can use queryDevices() to obtain the deviceId.
  deviceManager.unbindDevice(12345678, (error : BusinessError, data : number) => {
    if (error) {
      console.error(`unbindDevice async fail. Code is ${error.code}, message is ${error.message}`);
      return;
    }
    console.info(`unbindDevice success`);
  });
} catch (error) {
  console.error(`unbindDevice fail. Code is ${error.code}, message is ${error.message}`);
}

deviceManager.unbindDevice

unbindDevice(deviceId: number): Promise<number>

Unbinds a peripheral device. This API uses a promise to return the result.

Required permissions: ohos.permission.ACCESS_EXTENSIONAL_DEVICE_DRIVER

System capability: SystemCapability.Driver.ExternalDevice

Parameters

Name	Type	Mandatory	Description
deviceId	number	Yes	ID of the device to unbind. It can be obtained by queryDevices().

Error codes

ID	Error Message
401	The parameter check failed.
22900001	ExternalDeviceManager service exception.

Return value

Type	Description
Promise<number>	Promise used to return the device ID.

Example

import deviceManager from "@ohos.driver.deviceManager";
import { BusinessError } from '@ohos.base';

try {
  // For example, deviceId is 12345678. You can use queryDevices() to obtain the deviceId.
  deviceManager.unbindDevice(12345678).then((data : number) => {
    console.info(`unbindDevice success, Device_Id is ${data}.`);
  }, (error : BusinessError) => {
    console.error(`unbindDevice async fail. Code is ${error.code}, message is ${error.message}`);
  });
} catch (error) {
  console.error(`unbindDevice fail. Code is ${error.code}, message is ${error.message}`);
}