reference/apis/js-apis-inner-multimedia-soundPool.md

# SoundPool (Sound Pool)

The **SoundPool** module provides APIs for loading, unloading, playing, and stopping playing system sounds, setting the volume, and setting the number of loops.

Before using these APIs, you must call [media.createSoundPool](js-apis-media.md#mediacreatesoundpool10) to create a **SoundPool** instance.

> **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

```js
import media from '@ohos.multimedia.media';
import audio from '@ohos.multimedia.audio';
```

## PlayParameters

Describes the playback parameters of the sound pool.

These parameters are used to control the playback volume, number of loops, and priority.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

| Name           | Type                                    | Mandatory| Description                                                        |
| --------------- | ---------------------------------------- | ---- | ------------------------------------------------------------ |
| loop | number   | No | Number of loops. The value **0** means that the sound does not loop (the sound is played once), and **-1** means that the sound loops forever.                  |
| rate | number    | No | Playback rate. For details, see [AudioRendererRate](js-apis-audio.md#AudioRendererRate).|
| leftVolume  | number | No | Volume of the left channel. The value ranges from 0 to 1.                                   |
| rightVolume | number  | No | Volume of the right channel. (Currently, the volume cannot be set separately for the left and right channels. The volume set for the left channel is used.)|
| priority  | number  | No | Playback priority. The value **0** means the lowest priority. A larger value indicates a higher priority.     |
| parallelPlayFlag | boolean | No  | Whether the sound can be played in parallel with other active audio streams. The value **true** means that the sound can be played in parallel with other active audio streams, without preempting the audio focus, and **false** means the opposite.|

## SoundPool

Implements a sound pool that provides APIs for loading, unloading, playing, and stopping playing system sounds, setting the volume, and setting the number of loops. Before using these APIs, you must call [createSoundPool](js-apis-media.md#mediacreatesoundpool10) to create a **SoundPool** instance.

### load

load(uri: string, callback: AsyncCallback\<number>): void

Loads a sound. This API uses an asynchronous callback to obtain the sound ID. The input parameter **uri** is a string starting with fd://, which is generated based on the file descriptor (FD) obtained.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                                  | Mandatory| Description                                 |
| -------- | -------------------------------------- | ---- | ------------------------------------- |
| uri   | string | Yes  | URI of the audio file to load. Generally, the URI starts with fd://.|
| callback | AsyncCallback\<number>                   | Yes  | Callback used to return the ID of the sound loaded. A valid value must be greater than 0.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operation not allowed. Return by callback.|
| 5400103  | I/O error. Return by callback. |
| 5400105  | Service died. Return by callback. |

**Example**

```js
let uri:string = "";

// Obtain the URI starting with fd://.
await fs.open('/test_01.mp3', fs.OpenMode.READ_ONLY).then((file: fs.File) => {
  console.info("file fd: " + file.fd);
  uri = 'fd://' + (file.fd).toString()
}); // '/test_01.mp3' here is only an example. You need to pass in the actual URI.

soundPool.load(uri, (error, soundId_: number) => {
  if (error) {
    console.info(`load soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info(`load soundPool Success` + JSON.stringify(soundId_))
  }
})
```

### load

load(uri: string): Promise\<number>

Loads a sound. This API uses a promise to obtain the sound ID. The input parameter **uri** is a starting with fd://, which is generated based on the FD obtained.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name| Type                                  | Mandatory| Description                      |
| ------ | -------------------------------------- | ---- | -------------------------- |
| uri | string | Yes  | URI of the audio file to load. Generally, the URI starts with fd://.|

**Return value**

| Type          | Description                                      |
| -------------- | ------------------------------------------ |
| Promise\<number> | Promise used to return the ID of the sound loaded. A valid value must be greater than 0.|

**Example**

```js
let uri:string = "";
let soundID: number;

// Obtain the URI starting with fd://.
await fs.open('/test_01.mp3', fs.OpenMode.READ_ONLY).then((file: fs.File) => {
  console.info("file fd: " + file.fd);
  uri = 'fd://' + (file.fd).toString()
}); // '/test_01.mp3' here is only an example. You need to pass in the actual URI.

soundPool.load(uri).then((soundId: number) => {
  console.info('soundPool load uri success');
  soundID = soundId;
}).catch((err) => {
  console.error('soundPool load failed and catch error is ' + err.message);
});

```

### load

load(fd: number, offset: number, length: number, callback: AsyncCallback\<number>): void

Loads a sound. This API uses an asynchronous callback to obtain the sound ID. The input parameter **fd** can be manually input or automatically obtained by reading the embedded resource of the application.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| fd     | number | Yes  | Resource handle, which is obtained by calling **resourceManager.getRawFileDescriptor**.    |
| offset | number | Yes  | Resource offset, which needs to be entered based on the preset resource information. An invalid value causes a failure to parse audio and video resources.|
| length | number | Yes  | Resource length, which needs to be entered based on the preset resource information. An invalid value causes a failure to parse audio and video resources.|
| callback | AsyncCallback\<number> | Yes  | Callback used to return the sound ID. A valid value must be greater than 0.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operation not allowed. Return by callback. |
| 5400103  |I/O error. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let fd: number;
let soundID: number;
let fileSize: number;
let maxOffset: number;

// Obtain the FD.
await fs.open('/test_01.mp3', fs.OpenMode.READ_ONLY).then((file: fs.File) => {
  console.info("file fd: " + file.fd);
  uri = 'fd://' + (file.fd).toString()
}); // '/test_01.mp3' here is only an example. You need to pass in the actual URI.
let stat: Stat = await fs.stat('/test_01.mp3');
fileSize = stat.size;
maxOffset = stat.size;

soundPool.load(fd, 0, fileSize, (error, soundId_: number) => {
  if (error) {
    console.info(`load soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    soundID = soundId_;
    console.info('load success soundid:' + soundId_);
  }
})

```

### load

load(fd: number, offset: number, length: number): Promise\<number>

Loads a sound. This API uses a promise to obtain the sound ID. The input parameter **fd** can be manually input or automatically obtained by reading the embedded resource of the application.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| fd     | number | Yes  | Resource handle, which is obtained by calling **resourceManager.getRawFileDescriptor**.    |
| offset | number | Yes  | Resource offset, which needs to be entered based on the preset resource information. An invalid value causes a failure to parse audio and video resources.|
| length | number | Yes  | Resource length, which needs to be entered based on the preset resource information. An invalid value causes a failure to parse audio and video resources.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<number> | Promise used to return the sound ID. A valid value must be greater than 0.|

**Example**

```js
let fd: number;
let soundID: number;
let fileSize: number;
let maxOffset: number;

// Obtain the FD.
await fs.open('/test_01.mp3', fs.OpenMode.READ_ONLY).then((file: fs.File) => {
  console.info("file fd: " + file.fd);
  uri = 'fd://' + (file.fd).toString()
}); // '/test_01.mp3' here is only an example. You need to pass in the actual URI.
let stat = await fs.stat('/test_01.mp3');
fileSize = stat.size;
maxOffset = stat.size;

soundPool.load(fd, 0, fileSize).then((soundId: number) => {
  console.info('load success');
  soundID = soundId;
}).catch((err) => {
  console.error('soundpool load failed and catch error is ' + err.message);
});
```

### play

play(soundID: number, params: PlayParameters, callback: AsyncCallback\<number>): void

Plays a sound. This API uses an asynchronous callback to obtain the audio stream ID.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| soundID | number | Yes  | Sound ID, which is obtained by calling **load()**.|
| params | [PlayParameters](#playparameters) | Yes | Playback parameters.|
| callback | AsyncCallback\<number> | Yes  | Callback used to return the ID of the audio stream. A valid value must be greater than 0.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let soundID: number;
let streamID: number;
let PlayParameters: media.PlayParameters = {
    loop: number = 3, // The sound is played four times (three loops).
    rate: audio.AudioRendererRate = audio.AudioRendererRate.RENDER_RATE_NORMAL, // The sound is played at the original frequency.
    leftVolume: number = 0.5, // range = 0.0-1.0
    rightVolume: number = 0.5, // range = 0.0-1.0
    priority: number = 0 // The sound playback has the lowest priority.
    parallelPlayFlag: boolean = false // The sound is not played in parallel with other active audio streams.
  }
soundPool.play(soundID, PlayParameters, (error, streamId: number) => {
  if (error) {
    console.info(`play sound Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    streamID = streamId;
    console.info('play success soundid:' + streamId);
  }
})
```

### play

play(soundID: number, callback: AsyncCallback\<number>): void

Plays a sound. This API uses an asynchronous callback to obtain the audio stream ID.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| soundID | number | Yes  | Sound ID, which is obtained by calling **load()**.|
| callback | AsyncCallback\<number> | Yes  | Callback used to return the ID of the audio stream. A valid value must be greater than 0.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let soundID: number;
let streamID: number;
soundPool.play(soundID,  (error, streamId: number) => {
  if (error) {
    console.info(`play sound Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    streamID = streamId;
    console.info('play success soundid:' + streamId);
  }
})
```

### play

play(soundID: number, params?: PlayParameters): Promise\<number>

Plays a sound. This API uses a promise to obtain the audio stream ID.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| soundID | number | Yes  | Sound ID, which is obtained by calling **load()**.|
| params | [PlayParameters](#playparameters) | No | Playback parameters.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<number> | Promise used to return the ID of the audio stream. A valid value must be greater than 0.|

**Example**

```js
let soundID: number;
let streamID: number;
let PlayParameters: media.PlayParameters = {
    loop: number = 3, // The sound is played four times (three loops).
    rate: audio.AudioRendererRate = audio.AudioRendererRate.RENDER_RATE_NORMAL, // The sound is played at the original frequency.
    leftVolume: number = 0.5, // range = 0.0-1.0
    rightVolume: number = 0.5, // range = 0.0-1.0
    priority: number = 0 // The sound playback has the lowest priority.
    parallelPlayFlag: boolean = false // The sound is not played in parallel with other active audio streams.
  }

soundPool.play(soundID, PlayParameters).then((streamId: number) => {
  console.info('play success');
  streamID = streamId;
}).catch((err) => {
  console.error('soundpool play failed and catch error is ' + err.message);
});
```

### stop

stop(streamID: number, callback: AsyncCallback\<void>): void

Stops playing a sound. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
soundPool.stop(streamID, (error) => {
  if (error) {
    console.info(`stop sound Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('stop success');
  }
})

```

### stop

stop(streamID: number): Promise\<void>

Stops playing a sound. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.

soundPool.stop(streamID).then(() => {
  console.info('stop success');
}).catch((err) => {
  console.error('soundpool load stop and catch error is ' + err.message);
});
```

### setLoop

setLoop(streamID: number, loop: number, callback: AsyncCallback\<void>): void;

Sets the loop mode for an audio stream. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| loop | number | Yes  | Number of loops. The value **0** means that the sound does not loop (the sound is played once), and a value smaller than **0** means that the sound loops forever.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operate not permit. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
// Set the number of loops to 2.
soundPool.setLoop(streamID, 2, (error) => {
  if (error) {
    console.info(`setLoop soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('setLoop success streamID:' + streamID);
  }
})
```

### setLoop

setLoop(streamID: number, loop: number): Promise\<void>

Sets the loop mode for an audio stream. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| loop | number | Yes  | Number of loops. The value **0** means that the sound does not loop (the sound is played once), and a value smaller than **0** means that the sound loops forever.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
// Set the number of loops to 1.
soundPool.setLoop(streamID, 1).then(() => {
  console.info('setLoop success streamID:' + streamID);
}).catch((err) => {
  console.error('soundpool setLoop failed and catch error is ' + err.message);
});
```

### setPriority

setPriority(streamID: number, priority: number, callback: AsyncCallback\<void>): void

Sets the priority for an audio stream. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| priority | number | Yes  | Priority. The value **0** means the lowest priority.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operate not permit. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
// Set the priority to 1.
soundPool.setPriority(streamID, 1, (error) => {
  if (error) {
    console.info(`setPriority soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('setPriority success streamID:' + streamID);
  }
})

```

### setPriority

setPriority(streamID: number, priority: number): Promise\<void>

Sets the priority for an audio stream. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| priority | number | Yes  | Priority. The value **0** means the lowest priority.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
// Set the priority to 1.

soundPool.setPriority(streamID, 1).then(() => {
  console.info('setPriority success');
}).catch((err) => {
  console.error('soundpool setPriority failed and catch error is ' + err.message);
});
```

### setRate

setRate(streamID: number, rate: audio.AudioRendererRate, callback: AsyncCallback\<void>): void

Sets the playback rate for an audio stream. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| rate | [audio.AudioRendererRate](js-apis-audio.md#audiorendererrate8) | Yes  | Playback rate.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operate not permit. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let streamID: number;
let selectedAudioRendererRate: audio.AudioRendererRate = audio.AudioRendererRate.RENDER_RATE_NORMAL; // The sound is played at the original frequency.
// Call play() to obtain the stream ID.

soundPool.setRate(streamID, selectedAudioRendererRate, (error) => {
  if (error) {
    console.info(`setRate soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('setRate success streamID:' + streamID);
  }
})

```

### setRate

setRate(streamID: number, rate: audio.AudioRendererRate): Promise\<void>

Sets the playback rate for an audio stream. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| rate | [audio.AudioRendererRate](js-apis-audio.md#audiorendererrate8) | Yes  | Playback rate.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let streamID: number;
let selectedAudioRendererRate: audio.AudioRendererRate = audio.AudioRendererRate.RENDER_RATE_NORMAL; // The sound is played at the original frequency.
// Call play() to obtain the stream ID.

soundPool.setRate(streamID, selectedAudioRendererRate).then(() => {
  console.info('setRate success');
}).catch((err) => {
  console.error('soundpool setRate failed and catch error is ' + err.message);
});
```

### setVolume

setVolume(streamID: number, leftVolume: number, rightVolume: number, callback: AsyncCallback\<void>): void

Sets the volume for an audio stream. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| leftVolume | number | Yes  | Volume of the left channel. The value ranges from 0.0 to 1.0.|
| rightVolume | number | Yes  | Volume of the right channel. Currently, setting the volume for the right channel does not take effect. The volume set for the left channel is used.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operate not permit. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let streamID: number;
// Call play() to obtain the stream ID.
// Set the volume to 0.5.
soundPool.setVolume(streamID, 0.5, 0.5, (error) => {
  if (error) {
    console.info(`setVolume soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('setVolume success streamID:' + streamID);
  }
})

```

### setVolume

setVolume(streamID: number, leftVolume: number, rightVolume: number): Promise<void>

Sets the volume for an audio stream. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| streamID | number | Yes  | Audio stream ID, which is obtained by calling **play()**.|
| leftVolume | number | Yes  | Volume of the left channel. The value ranges from 0.0 to 1.0.|
| rightVolume | number | Yes  | Volume of the right channel. Currently, setting the volume for the right channel does not take effect. The volume set for the left channel is used.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let streamID: number;
selectedAudioRendererRate: number = 0; // The sound plays at the original frequency.
// Call play() to obtain the stream ID.

soundPool.setVolume(streamID, 0.5, 0.5).then(() => {
  console.info('setVolume success');
}).catch((err) => {
  console.error('soundpool setVolume failed and catch error is ' + err.message);
});
```

### unload

unload(soundID: number, callback: AsyncCallback\<void>): void

Unloads a sound. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| soundID | number | Yes  | Sound ID, which is obtained by calling **load()**.|
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400102  | Operation not allowed. Return by callback. |
| 5400103  | I/O error. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
let soundID: number;
// Call load() to obtain the sound ID.
soundPool.unload(soundID, (error) => {
  if (error) {
    console.info(`unload soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('unload success:');
  }
})

```

### unload

unload(soundID: number): Promise\<void>

Unloads a sound. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| soundID | number | Yes  | Sound ID, which is obtained by calling **load()**.|

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js
let soundID: number;
// Call load() to obtain the sound ID.

soundPool.unload(soundID).then(() => {
  console.info('unload success');
}).catch((err) => {
  console.error('soundpool unload failed and catch error is ' + err.message);
});
```

### release

release(callback: AsyncCallback\<void>): void

Releases this **SoundPool** instance. This API uses an asynchronous callback to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type                  | Mandatory| Description                       |
| -------- | ---------------------- | ---- | --------------------------- |
| callback | AsyncCallback\<void> | Yes  | Callback used to return the result.|

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400105  | Service died. Return by callback.       |

**Example**

```js

soundPool.release((error) => {
  if (error) {
    console.info(`release soundPool Error: errCode is ${error.code}, errMessage is ${error.message}`)
  } else {
    console.info('release success');
  }
})

```

### release

release(): Promise\<void>

Releases this **SoundPool** instance. This API uses a promise to return the result.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Return value**

| Type            | Description                            |
| ---------------- | -------------------------------- |
| Promise\<void> | Promise that returns no value.|

**Example**

```js

soundPool.release().then(() => {
  console.info('release success');
}).catch((err) => {
  console.error('soundpool release failed and catch error is ' + err.message);
});
```

### on('loadComplete')

on(type: 'loadComplete', callback: Callback<number>): void

Subscribes to events indicating that a sound finishes loading.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type    | Mandatory| Description                                                        |
| -------- | -------- | ---- | ------------------------------------------------------------ |
| type     | string   | Yes  | Event type, which is **'loadComplete'** in this case. This event is triggered when a sound is loaded.|
| callback | Callback\<number> | Yes  | ID of the sound that has been loaded.                              |

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400103  | IO error. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
soundPool.on('loadComplete', (soundId: number) => {
  console.info('loadComplete success, soundId: ' + soundId)
})
```

### off('loadComplete')

off(type: 'loadComplete'): void

Unsubscribes from events indicating that a sound finishes loading.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name| Type  | Mandatory| Description                                                        |
| ------ | ------ | ---- | ------------------------------------------------------------ |
| type   | string | Yes  | Event type. The value is fixed at **'loadComplete'**.|

**Example**

```js
soundPool.off('loadComplete')
```

### on('playFinished')

on(type: 'playFinished', callback: Callback<void>): void

Subscribes to events indicating that a sound finishes playing.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type    | Mandatory| Description                                                        |
| -------- | -------- | ---- | ------------------------------------------------------------ |
| type     | string   | Yes  | Event type, which is **'playFinished'** in this case. This event is triggered when a sound finishes playing.|
| callback | Callback\<void> | Yes  |  Callback used to return the result.       |

**Error codes**

For details about the error codes, see [Media Error Codes](../errorcodes/errorcode-media.md).

| ID| Error Message                               |
| -------- | --------------------------------------- |
| 5400103  | IO error. Return by callback. |
| 5400105  | Service died. Return by callback.       |

**Example**

```js
soundPool.on('playFinished', () => {
  console.info('playFinished success')
})
```

### off('playFinished')

off(type: 'playFinished'): void

Unsubscribes from events indicating that a sound finishes playing.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name| Type  | Mandatory| Description                                                        |
| ------ | ------ | ---- | ------------------------------------------------------------ |
| type   | string | Yes  | Event type. The value is fixed at **'playFinished'**.|

**Example**

```js
soundPool.off('playFinished')
```

### on('error')

on(type: 'error', callback: ErrorCallback): void

Subscribes to error events of this **SoundPool** instance. This event is used only for error prompt.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name  | Type    | Mandatory| Description                                                        |
| -------- | -------- | ---- | ------------------------------------------------------------ |
| type     | string   | Yes  | Event type, which is **'error'** in this case. This event can be triggered by both user operations and the system.|
| callback | function | Yes  | Callback used to return the error code ID and error message.|

The **SoundPool** class provides the following error types<a name = error_info></a>:

| ID| Error Message             | Description                                                        |
| -------- | --------------------- | ------------------------------------------------------------ |
| 401      | Invalid Parameter:    | Incorrect input parameter, causing an invalid call.                                    |
| 801      | Unsupport Capability: | Unsupported API, causing an invalid call.                             |
| 5400101  | No Memory:            | Insufficient memory.|
| 5400102  | Operation Not Allowed:   | Unsupported operation in the current state, causing an invalid call.                      |
| 5400103  | IO Error:             | I/O exception.|
| 5400105  | Service Died:         | The playback process is dead, and the service on which the sound pool depends is abnormal.|

**Example**

```js
soundPool.on('error', (error) => {
  console.error('error happened,and error message is :' + error.message)
  console.error('error happened,and error code is :' + error.code)
})
```

### off('error')

off(type: 'error'): void

Unsubscribes from error events of this **SoundPool** instance.

**System capability**: SystemCapability.Multimedia.Media.SoundPool

**Parameters**

| Name| Type  | Mandatory| Description                                     |
| ------ | ------ | ---- | ----------------------------------------- |
| type   | string | Yes  | Event type, which is **'error'** in this case.|

**Example**

```js
soundPool.off('error')
```