实例11--播放按键声音
? 实例11播放按键声音，在java me中有playTone的方法，可以指定一些特定的频率播放，在android中，我没找到相应的方法，所以就用了另一种方法，但是播放出来的生硬不是音乐的音符，只是其他的一些声音，下面给出源代码。因为简单，也没有涉及到界面，所以就不给出效果图，也没有MainView,就单单一个acitivity.
package com.wjh.test_tone;import android.app.Activity;import android.media.AudioManager;import android.media.ToneGenerator;import android.os.Bundle;import android.view.KeyEvent;public class TestTone extends Activity { /** Called when the activity is first created. */ToneGenerator tonePlayer = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); tonePlayer = new ToneGenerator(AudioManager.STREAM_MUSIC, 70); }@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event) {// TODO Auto-generated method stubswitch(keyCode){case KeyEvent.KEYCODE_0:tonePlayer.startTone(ToneGenerator.TONE_DTMF_0,100);break;case KeyEvent.KEYCODE_1:tonePlayer.startTone(ToneGenerator.TONE_DTMF_1,100);break;case KeyEvent.KEYCODE_2:tonePlayer.startTone(ToneGenerator.TONE_DTMF_2,100);break;case KeyEvent.KEYCODE_3:tonePlayer.startTone(ToneGenerator.TONE_DTMF_3,100);break;case KeyEvent.KEYCODE_4:tonePlayer.startTone(ToneGenerator.TONE_DTMF_4,100);break;case KeyEvent.KEYCODE_5:tonePlayer.startTone(ToneGenerator.TONE_DTMF_5,100);break;case KeyEvent.KEYCODE_6:tonePlayer.startTone(ToneGenerator.TONE_DTMF_6,100);break;case KeyEvent.KEYCODE_7:tonePlayer.startTone(ToneGenerator.TONE_DTMF_7,100);break;case KeyEvent.KEYCODE_8:tonePlayer.startTone(ToneGenerator.TONE_DTMF_8,100);break;case KeyEvent.KEYCODE_9:tonePlayer.startTone(ToneGenerator.TONE_DTMF_9,100);break;}return super.onKeyDown(keyCode, event);} }?在想playtone的时候，我在csdn发问了，fontlose回答了一种方法，我觉得还不错，有发出那7个声音，下面给出他提供的方法源码：
private final int duration = 1; // seconds private final int sampleRate = 8000; private final int numSamples = duration * sampleRate; private final double sample[] = new double[numSamples]; private final double freqOfTone[] ={262, 294,330,349,392,440,494,524}; // do，rui，mi，fa，so，la，xi，dou的频率 private final byte generatedSnd[] = new byte[2 * numSamples]; private int freqCnt=0; class PlayThread extends Thread { private int playfreq;//播放频率 public PlayThread(int cnt) { playfreq=cnt%8; } @Override public void run() { // TODO Auto-generated method stub for (int i = 0; i < numSamples; ++i) { sample[i] = Math.sin(2 * Math.PI * i / (sampleRate/freqOfTone[playfreq])); } int idx = 0; for (final double dVal : sample) { // scale to maximum amplitude final short val = (short) ((dVal * 32767)); // in 16 bit wav PCM, first byte is the low order byte generatedSnd[idx++] = (byte) (val & 0x00ff); generatedSnd[idx++] = (byte) ((val & 0xff00) >>> 8); } final AudioTrack audioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, sampleRate, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, numSamples, AudioTrack.MODE_STATIC); audioTrack.write(generatedSnd, 0, generatedSnd.length); audioTrack.play(); super.run(); } } new PlayThread(0).start(); //0播发duo 1播放rui 2播放mi ......?
?apk文件（将后缀改为 apk）：Demon_11.zip
源代码文件:Demon_11.rar