小编Dan*_*rez的帖子

大家晚上好!

我有以下麻烦:我正在尝试使用我的手机麦克风测量分贝(声音),但不知道为什么它不起作用!任何建议??感谢您的帮助!!

该计划是这样的:

`package com.dani;



import java.io.IOException;


import android.media.MediaRecorder;
import android.os.Bundle;
import android.app.Activity;

import android.widget.TextView;

public class Pruebita2 extends Activity {

TextView TextView;
StringBuilder builder=new StringBuilder();
MediaRecorder  mRecorder;
double powerDb;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.pruebita2);
TextView=new TextView(this);
setContentView(TextView);

mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mRecorder.setOutputFile("/dev/null"); 
try {
    mRecorder.prepare();
} catch (IllegalStateException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}
mRecorder.start();

}
public double getAmplitude() {
if (mRecorder != …