illegalStateException in android_问答_开发者_运维开发者技术经验分享

I taken sound recording code from http://developer.android.com/guide/topics/media/index.html, after running it on my emulator it is throwing illegalStateException, I also tried in my device, but there also its same thing.

I am new to android, please help me

package com.android.audiorecordtest;

import android.app.Activity;
import android.widget.LinearLayout;
import android.os.Bundle;
import android.os.Environment;
import android.view.ViewGroup;
import android.widget.Button;
import android.view.View;
import android.view.View.OnClickListener;
import android.content.Context;
import android.util.Log;
import android.media.MediaRecorder;
import android.media.MediaPlayer;

import java.io.IOException;


public class AudioRecordTest extends Activity
{
    private static final String LOG_TAG = "AudioRecordTest";
    private static String mFileName = null;

    private RecordButton mRecordButton = null;
    private MediaRecorder mRecorder = null;

    private PlayButton   mPlayButton = null;
    private MediaPlayer   mPlayer = null;

    private void onRecord(boolean start) {
        if (start) {
            startRecording();
        } else {
            stopRecording();
        }
    }

    private void onPlay(boolean start) {
        if (start) {
            startPlaying();
        } else {
            stopPlaying();
        }
    }

    private void startPlaying() {
        mPlayer = new MediaPlayer();
        try {
            mPlayer.setDataSource(mFileName);
            mPlayer.prepare();
            mPlayer.start();
        } catch (IOException e) {
            Log.e(LOG_TAG, "prepare() failed");
        }
    }

    private void stopPlaying() {
        mPlayer.release();
        mPlayer = null;
    }

    private void startRecording() {
        mRecorder = new MediaRecorder();
        mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        mRecorder.setOutputFormat(MediaRecorder.OutputFor开发者_如何学Pythonmat.THREE_GPP);
        mRecorder.setOutputFile(mFileName);
        mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);

        try {
            mRecorder.prepare();
        } catch (IOException e) {
            Log.e(LOG_TAG, "prepare() failed");
        }

        mRecorder.start();
    }

    private void stopRecording() {
        mRecorder.stop();
        mRecorder.release();
        mRecorder = null;
    }

    class RecordButton extends Button {
        boolean mStartRecording = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onRecord(mStartRecording);
                if (mStartRecording) {
                    setText("Stop recording");
                } else {
                    setText("Start recording");
                }
                mStartRecording = !mStartRecording;
            }
        };

        public RecordButton(Context ctx) {
            super(ctx);
            setText("Start recording");
            setOnClickListener(clicker);
        }
    }

    class PlayButton extends Button {
        boolean mStartPlaying = true;

        OnClickListener clicker = new OnClickListener() {
            public void onClick(View v) {
                onPlay(mStartPlaying);
                if (mStartPlaying) {
                    setText("Stop playing");
                } else {
                    setText("Start playing");
                }
                mStartPlaying = !mStartPlaying;
            }
        };

        public PlayButton(Context ctx) {
            super(ctx);
            setText("Start playing");
            setOnClickListener(clicker);
        }
    }

    public AudioRecordTest() {
        mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
        mFileName += "/audiorecordtest.3gp";
    }

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);

        LinearLayout ll = new LinearLayout(this);
        mRecordButton = new RecordButton(this);
        ll.addView(mRecordButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        mPlayButton = new PlayButton(this);
        ll.addView(mPlayButton,
            new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                0));
        setContentView(ll);
    }

    @Override
    public void onPause() {
        super.onPause();
        if (mRecorder != null) {
            mRecorder.release();
            mRecorder = null;
        }

        if (mPlayer != null) {
            mPlayer.release();
            mPlayer = null;
        }
    }
}

Stack Trace:

> 06-01 11:06:18.440:
> ERROR/AndroidRuntime(724): Uncaught
> handler: thread main exiting due to
> uncaught exception 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):
> java.lang.IllegalStateException 06-01
> 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.media.MediaRecorder.start(Native
> Method) 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.example.android.whereareyou.Main.startRecording(Main.java:75)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.example.android.whereareyou.Main.onRecord(Main.java:32)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.example.android.whereareyou.Main.access$0(Main.java:30)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.example.android.whereareyou.Main$RecordButton$1.onClick(Main.java:89)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.View.performClick(View.java:2179)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.View.onTouchEvent(View.java:3828)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.widget.TextView.onTouchEvent(TextView.java:6291)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.View.dispatchTouchEvent(View.java:3368)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:863)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:863)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:863)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:863)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1707)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1197)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.app.Activity.dispatchTouchEvent(Activity.java:1993)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1691)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.view.ViewRoot.handleMessage(ViewRoot.java:1525)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.os.Handler.dispatchMessage(Handler.java:99)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.os.Looper.loop(Looper.java:123)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> android.app.ActivityThread.main(ActivityThread.java:3948)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> java.lang.reflect.Method.invokeNative(Native
> Method) 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> java.lang.reflect.Method.invoke(Method.java:521)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:782)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> com.android.internal.os.ZygoteInit.main(ZygoteInit.java:540)
> 06-01 11:06:18.449:
> ERROR/AndroidRuntime(724):     at
> dalvik.system.NativeStart.main(Native
> Method)

Try to use that:-

public class VoiceRecorder extends Activity {
/** Called when the activity is first created. */
private MediaRecorder mediaRecorder;
boolean recording= false;
private Button start; //Start Button to start the recordings
private Button stop; // Stop button to stop the recordings
@Override
public void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.voice_recorder);
    mediaRecorder = new MediaRecorder();
    start = (Button)findViewById(R.id.start);

    //Activity when user click the start Button
    start.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            // TODO Auto-generated method stub
            settings();
            recordPrepare();
            mediaRecorder.start();
            recording = true;

        }

    });

    //Activity when user click the stop Button
    stop = (Button)findViewById(R.id.stop);
    stop.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            // TODO Auto-generated method stub

            if(recording)
            {
                mediaRecorder.stop();
                mediaRecorder.release();
                recording = false;
                settings();
                recordPrepare();
            }

        }
    });
}
//Settings for Audio Recorder
private void settings()
{
    long name = new Date().getTime();
    mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT);
    mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT);
    mediaRecorder.setOutputFile("/sdcard/"+Long.toString(name)+".3gp");
    DataModel dbModel = new DataModel(this);
    Calendar cal = Calendar.getInstance();
    dbModel.insertMultimedia("/sdcard/"+Long.toString(name)+".3gp", Long.toString(name), cal);
}
//prepare the Environment for Recording
private void recordPrepare()
{
    try
    {
        mediaRecorder.prepare();
    }
    catch(IllegalStateException e)
    {
        e.printStackTrace();

    } 
    catch (IOException e) 
    {
        e.printStackTrace();
    }
}

}

This will work fine. and file will be stored into SD card. you can also play by using play method as you have used in your code.

The problem in the code provided there is that the name of the filename where you record (mFileName) is null.

You can just call AudioRecordTest() before calling mRecorder.setOutputFile(mFileName) on startRecording() method. That should work. At least it did for me.