Using TonePlayer for Audio Playback (for System Applications Only)

TonePlayer⁹⁺ provides APIs for playing and managing Dual Tone Multi Frequency (DTMF) tones, such as dial tones, ringback tones, supervisory tones, and proprietary tones. The main task of the TonePlayer is to generate sine waves of different frequencies by using the built-in algorithm based on the ToneType and add the sine waves to create a sound. The sound can then be played by using the AudioRenderer, and the playback task can also be managed by using the AudioRenderer. The full process includes loading the DTMF tone configuration, starting DTMF tone playing, stopping the playback, and releasing the resources associated with the TonePlayer object. For details about the APIs, see the TonePlayer API Reference.

Supported Tone Types

The table below lists the supported tone types. You can call load() with audio.ToneType.type as a parameter to load the tone resource of the specified type.

Tone Type	Value	Description
TONE_TYPE_DIAL_0	0	DTMF tone of key 0.
TONE_TYPE_DIAL_1	1	DTMF tone of key 1.
TONE_TYPE_DIAL_2	2	DTMF tone of key 2.
TONE_TYPE_DIAL_3	3	DTMF tone of key 3.
TONE_TYPE_DIAL_4	4	DTMF tone of key 4.
TONE_TYPE_DIAL_5	5	DTMF tone of key 5.
TONE_TYPE_DIAL_6	6	DTMF tone of key 6.
TONE_TYPE_DIAL_7	7	DTMF tone of key 7.
TONE_TYPE_DIAL_8	8	DTMF tone of key 8.
TONE_TYPE_DIAL_9	9	DTMF tone of key 9.
TONE_TYPE_DIAL_S	10	DTMF tone of the star key (*).
TONE_TYPE_DIAL_P	11	DTMF tone of the pound key (#).
TONE_TYPE_DIAL_A	12	DTMF tone of key A.
TONE_TYPE_DIAL_B	13	DTMF tone of key B.
TONE_TYPE_DIAL_C	14	DTMF tone of key C.
TONE_TYPE_DIAL_D	15	DTMF tone of key D.
TONE_TYPE_COMMON_SUPERVISORY_DIAL	100	Supervisory tone - dial tone.
TONE_TYPE_COMMON_SUPERVISORY_BUSY	101	Supervisory tone - busy.
TONE_TYPE_COMMON_SUPERVISORY_CONGESTION	102	Supervisory tone - congestion.
TONE_TYPE_COMMON_SUPERVISORY_RADIO_ACK	103	Supervisory tone - radio path acknowledgment.
TONE_TYPE_COMMON_SUPERVISORY_RADIO_NOT_AVAILABLE	104	Supervisory tone - radio path not available.
TONE_TYPE_COMMON_SUPERVISORY_CALL_WAITING	106	Supervisory tone - call waiting tone.
TONE_TYPE_COMMON_SUPERVISORY_RINGTONE	107	Supervisory tone - ringing tone.
TONE_TYPE_COMMON_SUPERVISORY_CALL_HOLDING¹⁸⁺	108	Call hold tone.
TONE_TYPE_COMMON_PROPRIETARY_BEEP	200	Proprietary tone - beep tone.
TONE_TYPE_COMMON_PROPRIETARY_ACK	201	Proprietary tone - ACK.
TONE_TYPE_COMMON_PROPRIETARY_PROMPT	203	Proprietary tone - PROMPT.
TONE_TYPE_COMMON_PROPRIETARY_DOUBLE_BEEP	204	Proprietary tone - double beep tone.

How to Develop

To implement audio playback with the TonePlayer, perform the following steps:

Create a TonePlayer instance.

import { audio } from '@kit.AudioKit';

let audioRendererInfo: audio.AudioRendererInfo = {
  usage: audio.StreamUsage.STREAM_USAGE_DTMF, // Audio stream usage type: DTMF. Set this parameter based on the service scenario.
  rendererFlags: 0 // AudioRenderer flag.
};

async function createTonePlayer() {
  let tonePlayerPromise = await audio.createTonePlayer(audioRendererInfo);
}

Load the DTMF tone configuration of the specified type.

async function load() {
  await tonePlayerPromise.load(audio.ToneType.TONE_TYPE_DIAL_0);
}

Start DTMF tone playing.

async function start() {
  await tonePlayerPromise.start();
}

Stop the tone that is being played.

async function stop() {
  await tonePlayerPromise.stop();
}

Release the resources associated with the TonePlayer instance.

async function release() {
  await tonePlayerPromise.release();
}

If the APIs are not called in the preceding sequence, the error code 6800301 NAPI_ERR_SYSTEM is returned.

Complete Sample Code

Refer to the following code to play the DTMF tone when the dial key on the keyboard is pressed.

To prevent the UI thread from being blocked, most TonePlayer calls are asynchronous. Each API provides the callback and promise functions. The following examples use the promise functions. For more information, see TonePlayer.

import { audio } from '@kit.AudioKit';
import { BusinessError } from '@kit.BasicServicesKit';

let timerPro : number;
// Promise mode.
async function testTonePlayerPromise(type: audio.ToneType) {
  console.info('testTonePlayerPromise start');
  if (timerPro) clearTimeout(timerPro);
  let tonePlayerPromise: audio.TonePlayer;
  let audioRendererInfo: audio.AudioRendererInfo = {
    usage: audio.StreamUsage.STREAM_USAGE_DTMF, // Audio stream usage type: DTMF. Set this parameter based on the service scenario.
    rendererFlags: 0 // AudioRenderer flag.
  };
  timerPro = setTimeout(async () => {
    try {
      console.info('testTonePlayerPromise: createTonePlayer');
      // Create a DTMF player.  
      tonePlayerPromise = await audio.createTonePlayer(audioRendererInfo);
      console.info('testTonePlayerPromise: createTonePlayer-success');
      console.info(`testTonePlayerPromise: load type: ${type}`);
      // Load the tone configuration of the specified type.
      await tonePlayerPromise.load(type);
      console.info('testTonePlayerPromise: load-success');
      console.info(`testTonePlayerPromise: start type: ${type}`);
      // Start DTMF tone playing.
      await tonePlayerPromise.start();
      console.info('testTonePlayerPromise: start-success');
      console.info(`testTonePlayerPromise: stop type: ${type}`);
      setTimeout(async()=>{
        // Stop the tone that is being played.
        await tonePlayerPromise.stop();
        console.info('testTonePlayerPromise: stop-success');
        console.info(`testTonePlayerPromise: release type: ${type}`);
        // Release the resources associated with the TonePlayer instance.
        await tonePlayerPromise.release();
        console.info('testTonePlayerPromise: release-success');
      }, 30)
    } catch(err) {
      let error = err as BusinessError;
      console.error(`testTonePlayerPromise err : ${error}`);
    }
  }, 200)
};

async function testTonePlayer() {
   testTonePlayerPromise(audio.ToneType.TONE_TYPE_DIAL_0);
}