我有这个Android问题一直给我带来困难。
我正在开发一款应用程序，只要手机通过麦克风感应到噪音，我就会播放声音。逻辑的核心是一个while循环，它从另一个类调用声音播放方法。
当设置方法将循环的条件切换为false时，此循环终止。问题出现在播放延迟直到循环条件设置为false的情况下。一旦循环结束，它会在混乱的爆炸中一次性播放声音播放方法的调用，而不是在循环的每次传递中调用它。
尽管在runOnUiThread内进行了线程化并将声音播放方法调用粘在一起，但仍然会发生这种情况。 MediaPlayer和SoundPool也会发生这种情况。我只想让playFart()方法在调用时完全播放。
NoiseActivatedFart
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageButton;
import android.widget.TextView;
public class NoiseActivatedFart extends Activity {
public static int raw = 0; //For debugging. Will be removed
public static int trigger = 0; //For debugging. Will be removed
private Animation press;
private boolean activate_button_state = true;
private EvaluateAmbientNoise evaluateAmbientNoise = new EvaluateAmbientNoise(this);
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.noise_activated_fart);
final TextView debugTextView = (TextView) findViewById(R.id.debug);
press = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.press);
final ImageButton activateButton = (ImageButton) findViewById(R.id.activateButton);
activateButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
if (activate_button_state) {
activateButton.startAnimation(press);
activate_button_state = false;
//The Android.MediaRecorder documentation recommends that objects
//be used in their own threads, as it can really drag the main thread down
new Thread() {
public void run(){
evaluateAmbientNoise.startListening();
}
}.start();
}
else {
activateButton.startAnimation(press);
debugTextView.setText(raw + " " + trigger);
activate_button_state = true;
evaluateAmbientNoise.stopListening();
System.out.println("stop listening");
}
}
});
}
}
评估环境噪音
import android.content.Context;
import android.media.MediaRecorder;
import android.app.Activity;
class EvaluateAmbientNoise implements Runnable {
Activity activity = new Activity();
int[] average = new int[10];
int averageNoiseLevel = 1;
int noiseTriggerLevel = 1;
Context context;
FartPlayer fartplayer = new FartPlayer();
MediaRecorder recorder = null;
boolean recorder_state = false;
boolean keepGoing = false;
/**
* Constructor
* The SoundPool object that is utilized by "fartPlayer"
* requires a context object to function, and gets it from here
*/
EvaluateAmbientNoise(Context input_context) {
context = input_context;
}
public void run() {
startListening();
}
/**
* startListening prepares and starts an Android.MediaRecorder object that is
* used for it's getMaxAmplitude() function. It checks the level of
* noise several times, averages them, and uses the average to determine a trigger level.
* It continues to check the levels and play a fart whenever the levels exceed the trigger.
* It continues until stopListening is called.
*/
public void startListening() {
prepareMediaRecorder();
startMediaRecorder();
fartplayer.initSounds(context);
//Gather sound levels, average them, and use it to make a trigger
averageNoiseLevel = 0;
for (int counter = 0; counter < 10; counter++) {
average[counter] = recorder.getMaxAmplitude();
System.out.println("getting values: " + average[counter]);
}
for (int i:average){
averageNoiseLevel += i;
System.out.println("averaging array: " + averageNoiseLevel);
}
averageNoiseLevel = averageNoiseLevel / average.length;
noiseTriggerLevel = (int)(averageNoiseLevel * 1.5);
System.out.println("average total : " + averageNoiseLevel);
System.out.println("trigger: " + noiseTriggerLevel);
//Listen for noise, and play a fart when the noise exceeds the trigger
keepGoing = true;
int currentLevel = 0;
while (keepGoing) {
currentLevel = recorder.getMaxAmplitude();
if (currentLevel > (noiseTriggerLevel)) {
activity.runOnUiThread(new Runnable() {
public void run() {
fartplayer.playFart();
}
});
}
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
System.err.println("Caught Exception: " + e.getMessage());
}
System.out.println("tick");
}
}
public static void sleep() {
System.out.println("sleeping 1000ms");
}
// Stops "startListening()"
public void stopListening() {
keepGoing = false;
stopMediaRecorder();
}
/**
* start and stopMediaRecorder essentially staples a crude state flag to an
* Android.MediaRecorder object. This is needed because of the object's different states,
* and its simultaneous lack of state-checking functions.
*/
private void startMediaRecorder() {
if (recorder_state == false) {
recorder.start();
recorder_state = true;
}
}
private void stopMediaRecorder() {
if (recorder_state == true) {
recorder.stop();
recorder.release();
recorder = null;
recorder_state = false;
}
}
/**
* prepareMediaRecorder initializes the Android.MediaRecorder object before use.
* Any calls to MediaRecorder throw an exception otherwise
*/
public void prepareMediaRecorder() {
recorder = new MediaRecorder();
recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
recorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
recorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
recorder.setOutputFile("/dev/null/");
try {
recorder.prepare();
}
catch (Exception e){
System.out.println("Caught IOException: " + e.getMessage());
}
}
}
放屁球员
import android.app.Activity;
import android.content.Context;
import android.media.AudioManager;
import android.media.SoundPool;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
public class FartPlayer extends Activity {
private final Random fartSelector = new Random();
private List<Integer> fartList = new ArrayList<Integer>();
SoundPool sp;
//Initializes the SoundPool object and loads some fart mp3s into it
public void initSounds(Context c) {
sp = new SoundPool(5, AudioManager.STREAM_MUSIC, 0);
fartList.add(sp.load(c, R.raw.fart1, 1));
fartList.add(sp.load(c, R.raw.fart2, 1));
fartList.add(sp.load(c, R.raw.fart3, 1));
fartList.add(sp.load(c, R.raw.fart4, 1));
fartList.add(sp.load(c, R.raw.fart5, 1));
fartList.add(sp.load(c, R.raw.fart6, 1));
}
//Plays a random fart from the SoundPool when called
public void playFart() {
sp.play(fartList.get(fartSelector.nextInt(fartList.size())),1f,1f,1,0,1f);
System.out.println("farting");
}
}
答案 0 :(得分：0)
问题在于：
public void initSounds(Context c) {
sp = new SoundPool(5, AudioManager.STREAM_MUSIC, 0);
fartList.add(sp.load(c, R.raw.fart1, 1));
fartList.add(sp.load(c, R.raw.fart2, 1));
fartList.add(sp.load(c, R.raw.fart3, 1));
fartList.add(sp.load(c, R.raw.fart4, 1));
fartList.add(sp.load(c, R.raw.fart5, 1));
fartList.add(sp.load(c, R.raw.fart6, 1));
}
一次加载所有声音，一旦播放，每次声音都会立即播放，因为每个声音都会被加载并立即播放。您可以尝试使用MediaPlayer：
import android.content.Context;
import android.media.MediaPlayer;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
public class FartPlayer {
private Random fartSelector = new Random();
private List<Integer> songs;
Context c;
MediaPlayer mp;
//Initializes the SoundPool object and loads some fart mp3s into it
public void initSounds(Context c) {
this.c = c;
mp = new MediaPlayer();
songs = new ArrayList<Integer>();
songs.add(0, fart1);//starts at 0 so random isnt messed up
songs.add(1, fart2);
songs.add(2, fart3);
songs.add(3, fart4);
songs.add(4, fart5);
songs.add(5, fart6);
}
//Plays a random fart from the SoundPool when called
public void playFart(){
int song;
song = songs.get(fartSelector.nextInt(songs.size()));//selects a random number from 0-5(up to 6)
mp = MediaPlayer.create(c, song);//sets up the output
mp.start();//plays
System.out.println("farting");
}
}
然而，它可以通过加载一个声音来解决：
Random r = new Random();
public void initSounds(Context c) {
this.c = c;
sp = new SoundPool(1, AudioManager.STREAM_MUSIC, 0);
songs = new ArrayList<Integer>();
songs.add(0, fart1);//starts at 0 so random isnt messed up
songs.add(1, fart2);
songs.add(2, fart3);
songs.add(3, fart4);
songs.add(4, fart5);
songs.add(5, fart6);
}
//Plays a random fart from the SoundPool when called
public void playFart(){
int song;
song = songs.get(fartSelector.nextInt(songs.size()));//selects a random number from 0-5(up to 6)
sp.load(c, song, 1);//if this doesnt work, comment this answer
sp.play(fartList.get(r.nextInt(fartList.size())));
System.out.println("farting");
}