尽管Google的SDK文档写到了相关的，内容但是实在是太短小精悍了，因为需要写个简单的Demo，所以学习了一下。
现在，我们一起来看看，到底要怎么去写吧：
首先，我们肯定要用到摄像头，因此需要在Manifest文件中声明使用权限：
<uses-permission android:name="android.permission.CAMERA" />如果还要使用一些硬件属性，那还要做额外的声明，例如：
<uses-feature android:name="android.hardware.camera"/><uses-feature:name="android.hardware.camera.autofocus"/>当然，你还想要录制音频的话，还得加上：
<uses-permission android:name="android.permission.RECORD_AUDIO" />
当我们在录制的时候，通常都想要看到我们正在拍什么，这就需要预览，而预览需要在一个SurfaceView上实现，因此我们要添加一个控件：
<SurfaceView android:id="@+id/surface_camera" xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="fill_parent"android:layout_height="fill_parent"android:layout_centerInParent="true"android:layout_weight="1"></SurfaceView>然后，我们来实现这个Activity：
public class CustomVideoCamera extends Activity implements SurfaceHolder.Callback{private static final String TAG = "CAMERA_TUTORIAL";private SurfaceView surfaceView;private SurfaceHolder surfaceHolder;private Camera camera;private boolean previewRunning; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.camera_surface); surfaceView = (SurfaceView) findViewById(R.id.surface_camera); surfaceHolder = surfaceView.getHolder(); surfaceHolder.addCallback(this); surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); } @Override public void surfaceCreated(SurfaceHolder holder) { camera = Camera.open(); if (camera != null){ Camera.Parameters params = camera.getParameters(); camera.setParameters(params); } else { Toast.makeText(getApplicationContext(), "Camera not available!", Toast.LENGTH_LONG).show(); finish(); } } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { if (previewRunning){ camera.stopPreview(); } Camera.Parameters p = camera.getParameters(); p.setPreviewSize(width, height); p.setPreviewFormat(PixelFormat.JPEG); camera.setParameters(p); try { camera.setPreviewDisplay(holder); camera.startPreview(); previewRunning = true; } catch (IOException e) { Log.e(TAG,e.getMessage()); e.printStackTrace(); } } @Override public void surfaceDestroyed(SurfaceHolder holder) { camera.stopPreview(); previewRunning = false; camera.release(); }}接着，我们就可以录制了：
private MediaRecorder mediaRecorder; private final int maxDurationInMs = 20000; private final long maxFileSizeInBytes = 500000; private final int videoFramesPerSecond = 20; public boolean startRecording(){ try { camera.unlock(); mediaRecorder = new MediaRecorder(); mediaRecorder.setCamera(camera); mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC); mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA); mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.DEFAULT); mediaRecorder.setMaxDuration(maxDurationInMs); tempFile = new File(getCacheDir(),cacheFileName); mediaRecorder.setOutputFile(tempFile.getPath()); mediaRecorder.setVideoFrameRate(videoFramesPerSecond); mediaRecorder.setVideoSize(surfaceView.getWidth(), surfaceView.getHeight()); mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.DEFAULT); mediaRecorder.setVideoEncoder(MediaRecorder.VideoEncoder.DEFAULT); mediaRecorder.setPreviewDisplay(surfaceHolder.getSurface()); mediaRecorder.setMaxFileSize(maxFileSizeInBytes); mediaRecorder.prepare();
mediaRecorder.start(); return true; } catch (IllegalStateException e) { Log.e(TAG,e.getMessage()); e.printStackTrace(); return false; } catch (IOException e) { Log.e(TAG,e.getMessage()); e.printStackTrace(); return false; } }停止拍摄，则：
public void stopRecording(){ mediaRecorder.stop(); camera.lock();}
这样的话，通过编译之后，在Android OS 2.1 和 2.2上都能实现了，但在部分机器上会有些小问题，主要是预览上，看到app内的预览是另开线程做的，不知道是否会有改善？
