Vibrator Development (ArkTS)

When to Use

You can set different vibration effects as needed, for example, customizing the vibration intensity, frequency, and duration for button touches, alarm clocks, and incoming calls.

For details about the APIs, see Vibrator.

Available APIs

Name	Description
startVibration(effect: VibrateEffect, attribute: VibrateAttribute): Promise<void>	Starts vibration with the specified effect and attribute. This API uses a promise to return the result.
startVibration(effect: VibrateEffect, attribute: VibrateAttribute, callback: AsyncCallback<void>): void	Starts vibration with the specified effect and attribute. This API uses an asynchronous callback to return the result.
stopVibration(stopMode: VibratorStopMode): Promise<void>	Stops vibration in the specified mode. This API uses a promise to return the result.
stopVibration(stopMode: VibratorStopMode, callback: AsyncCallback<void>): void	Stops vibration in the specified mode. This API uses an asynchronous callback to return the result.
stopVibration(): Promise<void>	Stops vibration in all modes. This API uses a promise to return the result.
stopVibration(callback: AsyncCallback<void>): void	Stops vibration in all modes. This API uses an asynchronous callback to return the result.
isSupportEffect(effectId: string): Promise<boolean>	Checks whether an effect ID is supported. This API uses a promise to return the result. This API uses a promise to return the result. The return value true means that the effect ID is supported, and false means the opposite.
isSupportEffect(effectId: string, callback: AsyncCallback<boolean>): void	Checks whether an effect ID is supported. This API uses an asynchronous callback to return the result. This API uses an asynchronous callback to return the result. The return value true means that the effect ID is supported, and false means the opposite.

Vibration Effect Description

Currently, three types of vibration effects are supported.

Name	Description
Fixed-Duration Vibration	Only a fixed duration is passed in, and the device vibrates based on the default intensity and frequency. For details about the vibration effect, see VibrateTime.
Preset Vibration	Certain vibration effects are preset for fixed scenes. For example, the effect "haptic.clock.timer" is preset to provide feedback when a user adjusts the timer. For details about the vibration effect, see VibratePreset.
Custom Vibration	Custom vibration enables you to design vibration effects by customizing a vibration configuration file and orchestrating vibration forms based on the corresponding rules. For details about the vibration effect, see VibrateFromFile.

The custom vibration configuration file is in JSON format. An example file is as follows:

{
    "MetaData": {
        "Create": "2023-01-09",
        "Description": "a haptic case",
        "Version": 1.0,
        "ChannelNumber": 1
    },
    "Channels": [
        {
            "Parameters": {
                "Index": 0
            },
            "Pattern": [
                {
                    "Event": {
                        "Type": "transient",
                        "StartTime": 0,
                        "Parameters": {
                            "Frequency": 31,
                            "Intensity": 100
                        }
                    }
                },
                {
                    "Event": {
                        "Type": "continuous",
                        "StartTime": 40,
                        "Duration": 54,
                        "Parameters": {
                            "Frequency": 30,
                            "Intensity": 38,
                            "Curve": [
                                {
                                    "Time": 0,
                                    "Frequency": 0,
                                    "Intensity": 0
                                },
                                {
                                    "Time": 1,
                                    "Frequency": 15,
                                    "Intensity": 0.5
                                },
                                {
                                    "Time": 40,
                                    "Frequency": -8,
                                    "Intensity": 1.0
                                },
                                {
                                    "Time": 54,
                                    "Frequency": 0,
                                    "Intensity": 0
                                }
                            ]
                        }
                    }
                }
            ]
        }
    ]
}

This JSON file contains three attributes: MetaData, Channels, and Parameters.

MetaData contains information about the file header. You can add the following attributes under MetaData.

Name	Mandatory	Description
Version	Yes	Version number of the file format, which is forward compatible. Currently, only version 1.0 is supported.
ChannelNumber	Yes	Number of channels for vibration. A maximum of two channels are supported.
Create	No	Time when the file was created.
Description	No	Additional information such as the vibration effect and creation information.

Channels provides information about the vibration channel.

It is a JSON array that holds information about each channel. It contains two attributes: Parameters and Pattern.

Name	Mandatory	Description
Parameters	Yes	Channel parameters. Among them, Index indicates the channel ID. The value 0 indicates both channels, 1 indicates the left channel, and 2 indicates the right channel.
Pattern	No	Vibration sequence.

Pattern is a JSON array that holds the vibration events. Under it, Event indicates a vibration event, which can be either of the following types:

Vibration Type	Description
transient	Short vibration.
continuous	Long vibration.

A vibration event contains the following attributes:

Name	Mandatory	Description
Type	Yes	Type of the vibration event, which can be transient or continuous.
StartTime	Yes	Vibration start time. The value range is [0, 1800000], in ms.
Duration	Yes	Vibration duration. This parameter is valid only when Type is set to continuous. The value range is [0, 5000], in ms.

Parameters provides the following parameters related to the vibration event and is mandatory.

Name	Mandatory	Description
Intensity	Yes	Vibration intensity. The value range is [0, 100].
Frequency	Yes	Vibration frequency. The value range is [0, 100].
Curve	No	Vibration curve. This parameter is valid only when Type is set to continuous. It is a JSON array that holds 4 to 16 adjustment points. Each adjustment point must contain the following attributes: Time: offset relative to the event start time. The value ranges from 0 to the vibration duration. Intensity: gain relative to the vibration intensity. The value range is [0, 1]. This value multiplied by the vibration intensity is the adjusted intensity at the corresponding time point. Frequency: change relative to the vibration frequency. The value range is [-100, 100]. This value plus the vibration frequency is the adjusted frequency at the corresponding time point.

The following requirements must be met:

Item	Description
Number of vibration events	No more than 128
Length of the vibration configuration file	Not greater than 64 KB

How to Develop

Before using the vibrator on a device, you must declare the ohos.permission.VIBRATE permission. For details, see Declaring Permissions.

Start vibration with the specified effect and attribute.

Scenario 1: Trigger vibration with the specified duration.

import { vibrator } from '@kit.SensorServiceKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  // Start vibration.
  vibrator.startVibration({
    type: 'time',
    duration: 1000,
  }, {
    id: 0,
    usage: 'alarm'
  }, (error: BusinessError) => {
    if (error) {
      console.error(`Failed to start vibration. Code: ${error.code}, message: ${error.message}`);
      return;
    }
    console.info('Succeed in starting vibration');
  });
} catch (err) {
  let e: BusinessError = err as BusinessError;
  console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
}

Scenario 2: Trigger vibration with a preset effect. You can check whether the preset effect is supported before calling startVibration().

import { vibrator } from '@kit.SensorServiceKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  // Check whether 'haptic.effect.soft' is supported.
  vibrator.isSupportEffect('haptic.effect.soft', (err: BusinessError, state: boolean) => {
    if (err) {
      console.error(`Failed to query effect. Code: ${err.code}, message: ${err.message}`);
      return;
    }
    console.info('Succeed in querying effect');
    if (state) {
      try {
        // Start vibration.
        vibrator.startVibration({
          type: 'preset',
          effectId: 'haptic.effect.soft',
          count: 1,
          intensity: 50,
        }, {
          usage: 'unknown'
        }, (error: BusinessError) => {
          if (error) {
            console.error(`Failed to start vibration. Code: ${error.code}, message: ${error.message}`);
          } else {
            console.info('Succeed in starting vibration');
          }
        });
      } catch (error) {
        let e: BusinessError = error as BusinessError;
        console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
      }
    }
  })
} catch (error) {
  let e: BusinessError = error as BusinessError;
  console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
}

Scenario 3: Trigger vibration according to a custom vibration configuration file.

import { vibrator } from '@kit.SensorServiceKit';
import { resourceManager } from '@kit.LocalizationKit';
import { BusinessError } from '@kit.BasicServicesKit';

const fileName: string = 'xxx.json';

@Entry
@Component
struct Index {
  uiContext = this.getUIContext();

  build() {
    Row() {
      Column() {
        Button('alarm-file')
          .onClick(() => {
            // Obtain the file descriptor of the vibration configuration file.
            let rawFd: resourceManager.RawFileDescriptor|undefined = this.uiContext.getHostContext()?.resourceManager.getRawFdSync(fileName);
            if (rawFd != undefined) {
              // Start vibration.
              try {
                vibrator.startVibration({
                  type: "file",
                  hapticFd: { fd: rawFd.fd, offset: rawFd.offset, length: rawFd.length }
                }, {
                  id: 0,
                  usage: 'alarm' // The switch control is subject to the selected type.
                }, (error: BusinessError) => {
                  if (error) {
                    console.error(`Failed to start vibration. Code: ${error.code}, message: ${error.message}`);
                    return;
                  }
                  console.info('Succeed in starting vibration');
                });
              } catch (err) {
                let e: BusinessError = err as BusinessError;
                console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
              }
            }
            // Close the file descriptor of the vibration configuration file.
            this.uiContext.getHostContext()?.resourceManager.closeRawFdSync(fileName);
          })
      }
      .width('100%')
    }
    .height('100%')
  }
}

Stop vibration.

Method 1: Stop vibration in the specified mode. This method is invalid for custom vibration.

Stop fixed-duration vibration.

import { vibrator } from '@kit.SensorServiceKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  // Stop vibration in VIBRATOR_STOP_MODE_TIME mode.
  vibrator.stopVibration(vibrator.VibratorStopMode.VIBRATOR_STOP_MODE_TIME, (error: BusinessError) => {
    if (error) {
      console.error(`Failed to stop vibration. Code: ${error.code}, message: ${error.message}`);
      return;
    }
    console.info('Succeed in stopping vibration');
  })
} catch (err) {
  let e: BusinessError = err as BusinessError;
  console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
}

Stop preset vibration.

import { vibrator } from '@kit.SensorServiceKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  // Stop vibration in VIBRATOR_STOP_MODE_PRESET mode.
  vibrator.stopVibration(vibrator.VibratorStopMode.VIBRATOR_STOP_MODE_PRESET, (error: BusinessError) => {
    if (error) {
      console.error(`Failed to stop vibration. Code: ${error.code}, message: ${error.message}`);
      return;
    }
    console.info('Succeed in stopping vibration');
  })
} catch (err) {
  let e: BusinessError = err as BusinessError;
  console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
}

Method 2: Stop vibration in all modes, including custom vibration.

import { vibrator } from '@kit.SensorServiceKit';
import { BusinessError } from '@kit.BasicServicesKit';

try {
  // Stop vibration in all modes.
  vibrator.stopVibration((error: BusinessError) => {
    if (error) {
      console.error(`Failed to stop vibration. Code: ${error.code}, message: ${error.message}`);
      return;
    }
    console.info('Succeed in stopping vibration');
  })
} catch (error) {
  let e: BusinessError = error as BusinessError;
  console.error(`An unexpected error occurred. Code: ${e.code}, message: ${e.message}`);
}