Record Video from Camera via Version Android 2.2

问题

enter code hereWhen I try to recording video from camera at version Android 2.2. It has some errors.No one could find the solution. İs there any bug Android MediaRecorder API. How can I solve this. I got more errors.You can see some of them in picture. And an error like that:Camera Preview -13 Thanks a lot.

http://i.stack.imgur.com/72lp7.png recorder.prepare() fails and throws Java.lang.illegalexeption Here is Code:

package app.raceway.com;

import java.io.File;
import java.io.IOException;

import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.hardware.Camera;
import android.media.CamcorderProfile;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;

public class VideoCapture extends Activity implements  SurfaceHolder.Callback {
    MediaRecorder recorder;
    SurfaceHolder holder;
    public Camera camera;
    File video;
    String filePath;
    boolean recording = false;
      private static final int FRAME_RATE = 15;

      private static final int CIF_WIDTH = 320;

      private static final int CIF_HEIGHT = 240;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);


    recorder = new MediaRecorder();

    setContentView(R.layout.main);

    SurfaceView cameraView = (SurfaceView) findViewById(R.id.cameraView);
    holder = cameraView.getHolder();
    holder.addCallback(this);
    holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    String path=Environment.getExternalStorageDirectory().getAbsolutePath()+
    "/video/videocapture_example.mpg4";
    // make sure the directory we plan to store the recording in exists
    File sampleDir = Environment.getExternalStorageDirectory();
    try { 
        video = new File(sampleDir+"/videofile.3gp");
        sampleDir.createNewFile();
          //video = File.createTempFile("videofile", ".3gp", sampleDir);
      } 
      catch (IOException e)
      {
          Log.e("deneme","sdcard access error");

      }
      filePath=video.getAbsolutePath();

}

private void initRecorder() {

    recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
    recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);

}
private void prepareRecorder() throws IOException{
    recorder.setCamera(camera);
    recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
    recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
    recorder.setVideoEncoder(MediaRecorder.VideoEncoder.H263);
    recorder.setOutputFile(filePath);
    recorder.setMaxDuration(50000); // 50 seconds
    recorder.setMaxFileSize(5000000); // Approximately 5 megabytes
try {

} catch (IllegalStateException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}


}



public void onclickSaveVideo(View v) throws IOException {
    if (recording) {
    Toast t=new Toast(getApplicationContext());
    t.makeText(getApplicationContext(), "Video Recording stopped",Toast.LENGTH_SHORT);
    t.show();
        recorder.stop();
        recording = false;

        // Let's initRecorder so we can record again
        initRecorder();     
    } else {
        try {
            prepareRecorder();
            //recorder.prepare();
        } catch (IllegalStateException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        recording = true;
        recorder.prepare();
        recorder.start();
        try {
            Thread.sleep(10000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        recorder.stop();
        Toast t=new Toast(getApplicationContext());
        t.makeText(getApplicationContext(), "Video Recording started",Toast.LENGTH_SHORT);
        t.show();
    }
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
    camera=Camera.open();

    try {
        camera.setPreviewDisplay(holder);
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    camera.startPreview();
    camera.unlock();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {

}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
    if (recording) {
        recorder.stop();
        recording = false;
    }
    recorder.release();
    finish();
    camera.release();
}


}

回答1:

Emin,

Based on the image of the logcat output you provide the crash is occuring with the start() method. You will see from the documentation for the start method that prepare() must be called first or else it will throw the IllegalStateException. In your code all the calls the prepare() are commented out?

EDIT: We sorted things out in the comments below my answer. He was running this code on an emulator and MediaRecorder is not supported by the emulator.

来源：https://stackoverflow.com/questions/6194830/record-video-from-camera-via-version-android-2-2