java - 为什么我无法激活 4 个按钮来开始录音？

Question

我正在开发一个音频应用程序，我想知道为什么我的录音机无法工作。根据 Eclipse，没有可见的错误，因此我很不清楚为什么我的录制按钮不起作用

这是我的 XML 布局:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >

<Button
    android:id="@+id/btnstart"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="47dp"
    android:onClick="buttonTapped"
    android:text="Start" />

<Button
    android:id="@+id/btnfinish"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/btnstart"
    android:layout_centerHorizontal="true"
    android:onClick="buttonTapped"
    android:text="Finish" />

<Button
    android:id="@+id/btnplay"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignRight="@+id/btnfinish"
    android:layout_below="@+id/btnfinish"
    android:onClick="buttonTapped"
    android:text="Play" />

<Button
    android:id="@+id/btnstop"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignRight="@+id/btnstart"
    android:layout_below="@+id/btnplay"
    android:onClick="buttonTaped"
    android:text="stop" />

</RelativeLayout>

声音类文件:

 package com.example.testproject;

    import java.io.File;
    import android.app.Activity;
    import android.media.MediaPlayer;
    import android.media.MediaRecorder;
    import android.os.Bundle;
    import android.os.Environment;
    import android.view.View;

    public class Sound extends Activity {

private MediaPlayer mediaPlayer;
private MediaRecorder recorder;
private String OUTPUT_FILE;


@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.audio);

    OUTPUT_FILE=Environment.getExternalStorageDirectory()+"/audiorecorder.3gpp";

}

public void buttonTapped(View view){

    switch(view.getId()){
    case R.id.btnstart:

    try {
        beginRecording();
    }catch(Exception e){
        e.printStackTrace();
    }

    break;

    case R.id.btnfinish:

    try {
        stopRecording();
    }catch(Exception e){
        e.printStackTrace();
    }

    break;

    case R.id.btnplay:

    try {
        playRecording();
    }catch(Exception e){
        e.printStackTrace();
    }

    break;

    case R.id.btnstop:

    try {
        stopPlayback();
    }catch(Exception e){
        e.printStackTrace();
    }

    break;
    }       

    }

private void stopPlayback(){

}

private void playRecording() throws Exception{
    ditchMediaPlayer();
    mediaPlayer = new MediaPlayer();
    mediaPlayer.setDataSource(OUTPUT_FILE);
    mediaPlayer.prepare();
    mediaPlayer.start();

}

private void ditchMediaPlayer(){
    if(mediaPlayer != null)
    {
        try{
            mediaPlayer.release();
        }catch(Exception e)
        {
            e.printStackTrace();
        }
    }
}

private void stopRecording(){

    if(recorder != null)
        recorder.stop();

}

private void beginRecording() throws Exception{

    ditchMediaRecorder();
    File outputFile = new File(OUTPUT_FILE);

    if(outputFile.exists())
        outputFile.delete();

    recorder = new MediaRecorder();
    recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
    recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
    recorder.setOutputFile(OUTPUT_FILE);
    recorder.prepare();
    recorder.start();

}

private void ditchMediaRecorder() { 
    if(recorder != null)
        recorder.release();
}

  }

AndroidManifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.camera"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
    android:minSdkVersion="3"
    android:targetSdkVersion="11" />

<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.testproject.Testproject"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

             <activity
        android:name=".Camera"
        android:label="@string/app_name" />
</application>

</manifest>

Answer 1

您似乎没有在 list 中设置适当的权限

添加

<uses-permission android:name="android.permission.RECORD_AUDIO" />

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

到您的 list 文件并检查。