android - 在无效状态 : 4 中调用 MediaRecorder 启动

Question

我刚刚开始涉足 Android/Glass 开发，我正在尝试添加基本的视频录制功能。目前，Glass 将你限制为 10 秒，除非你再次点击/按下按钮，我想绕过这个，只需要一个开放式录像机。

我跟着两个摄像头API演练:

并引用了另一个 project :

到目前为止，我的代码如下所示:

private void startRecording()
{
    try{
    camera = Camera.open();
    mediaRecorder = new MediaRecorder();
    surfaceView = new CamSurfaceView(this, camera);

    try {
        camera.setPreviewDisplay(surfaceView.getHolder());
    } catch (IOException e1) {

    }
    camera.startPreview();
    camera.unlock();
    mediaRecorder.setCamera(camera);
    mediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
    mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
    mediaRecorder.setProfile(CamcorderProfile.get(MediaRecorder.OutputFormat.MPEG_4));
    mediaRecorder.setOutputFile(getOutputMediaFile().toString());
    mediaRecorder.setPreviewDisplay(surfaceView.getHolder().getSurface());

    try{
    mediaRecorder.prepare();
    }
    catch(IllegalStateException e){

    }
    catch(IOException e){

    }
    mediaRecorder.start();  //Code failure occurs here.
    }
    catch(Exception e)
    {
        if(mediaRecorder != null)
            mediaRecorder.release();
        if(camera != null)
            camera.release();
    }
}
private Uri getOutputMediaFile()
{
    File mediaStorageDir = new File(Environment.getExternalStorageDirectory()+File.separator+"DCIM/Camera");

    File[] files =mediaStorageDir.listFiles();

    if(!mediaStorageDir.exists())
    {
        if(!mediaStorageDir.mkdirs())
        {
            Log.d("KarmaCam","Failed to create directory");
            return null;
        }
    }

    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    File file = new File(mediaStorageDir.getPath() + File.separator+ "VID_"+timeStamp+".mp4");
    return Uri.fromFile(file);

}

我的 SurfaceView:

public class KarmaCamSurfaceView extends SurfaceView implements SurfaceHolder.Callback {

private SurfaceHolder mHolder;
private Camera mCamera;

public CamSurfaceView(Context context, Camera camera) {
    super(context);
    mCamera = camera;
    mHolder = getHolder();
    mHolder.addCallback(this);      
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int weight, int height) {

    if(mHolder.getSurface() == null)
        return;     
    try
    {
        mCamera.stopPreview();  
    }
    catch(Exception e)  {}

    try
    {
        mCamera.setPreviewDisplay(mHolder);
        mCamera.startPreview();
    }
    catch(Exception e){}        
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
    try
    {
        mCamera.setPreviewDisplay(holder);
        mCamera.startPreview();
    }
    catch(Exception e){}

}

@Override
public void surfaceDestroyed(SurfaceHolder arg0) {
    // TODO Auto-generated method stub

}

我见过其他人有类似的问题/问题，它们通常发生在不正确的输出文件名格式周围。据我所知，我的没问题，但我很好奇目录路径是否有效。这是内置 Glass 视频的存储位置。

Answer 1

将您的位置更改为:

 Environment.getExternalStorageDirectory() + File.separator 
            + Environment.DIRECTORY_DCIM + File.separator + "FILE_NAME";

这对我有用。希望对您有所帮助!