public class CameraKitKat extends ACamera{private Camera camera;private SurfaceHolder holder;private float displayScale;public CameraKitKat(SurfaceView surfaceView) {super(surfaceView);init();}private void init(){holder=displayView.getHolder();}
　　//获得一个相机实例@Overridepublic void open(int type){　　　　//获取预览方向设置int rotation=((WindowManager)displayView.getContext().getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getRotation();　　　　//判断相机是否开启if(!openCamera(type))return;　　　　//修改相机设置setParameters(camera,rotation);　　　　//设置正确的预览方向setDisplayOrientation(camera,rotation);　　　　//设置预览的承载，如果没有这一步，相机无法开始预览setPreviewDisplay(camera,holder);　　　　//开启预览camera.startPreview();}@Overridepublic void close(){camera.stopPreview();camera.release();}//调整SurfaceView的大小private void resizeDisplayView(){　　　　//获得相机实例的默认设置Camera.Parameters parameters=camera.getParameters();　　　　//将预览View的Size和Camera的PreviewSize设置相同Camera.Size size=parameters.getPreviewSize();　　　　//返回布局参数的引用FrameLayout.LayoutParams p= (FrameLayout.LayoutParams) displayView.getLayoutParams();float scale=size.width/(float)size.height;displayScale=displayView.getHeight()/(float)displayView.getWidth();if(scale>displayScale){p.height= (int) (scale*displayView.getWidth());p.width=displayView.getWidth();}else{p.width= (int) (displayView.getHeight()/scale);p.height=displayView.getHeight();}Log.e("wuwang","-->"+size.width+"/"+size.height);Log.e("wuwang","--<"+p.height+"/"+p.width);displayView.setLayoutParams(p);displayView.invalidate();}
　　//获得当前设备的Camera个数，为0表示不支持摄像头private boolean checkCameraId(int cameraId){return cameraId>=0&&cameraId<Camera.getNumberOfCameras();}//相机使用第一步，打开相机，获得相机实例private boolean openCamera(int cameraId){if(!checkCameraId(cameraId))return false;camera=Camera.open(cameraId);return true;}//相机使用第二步，设置相机实例参数//TODO :里面还存在问题，需要修改private void setParameters(Camera camera,int rotation){Camera.Parameters parameters=camera.getParameters();//PreviewSize设置为设备支持的最高分辨率final Camera.Size size=Collections.max(camera.getParameters().getSupportedPreviewSizes(),new Comparator<Camera.Size>() {@Overridepublic int compare(Camera.Size lhs, Camera.Size rhs) {return lhs.width*lhs.height-rhs.width*rhs.height;}});parameters.setPreviewSize(size.width,size.height);//PictureSize设置为和预览大小最近的Camera.Size picSize=Collections.max(parameters.getSupportedPictureSizes(), new Comparator<Camera.Size>() {@Overridepublic int compare(Camera.Size lhs, Camera.Size rhs) {return (int) (Math.sqrt(Math.pow(size.width-rhs.width,2)+Math.pow(size.height-rhs.height,2))-Math.sqrt(Math.pow(size.width-lhs.width,2)+Math.pow(size.height-lhs.height,2)));}});parameters.setPictureSize(picSize.width,picSize.height);//如果相机支持自动聚焦，则设置相机自动聚焦，否则不设置if(parameters.getSupportedFocusModes().contains(Camera.Parameters.FOCUS_MODE_AUTO)){parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);}//设置颜色效果
//        parameters.setColorEffect(Camera.Parameters.EFFECT_MONO);camera.setParameters(parameters);resizeDisplayView();}//相机使用第三步，设置相机预览方向private void setDisplayOrientation(Camera camera,int rotation){if(rotation== Surface.ROTATION_0||rotation==Surface.ROTATION_180){camera.setDisplayOrientation(90);}else{camera.setDisplayOrientation(0);}}//相机使用第四步，设置相机预览载体SurfaceHolderprivate void setPreviewDisplay(Camera camera,SurfaceHolder holder){try {camera.setPreviewDisplay(holder);} catch (IOException e) {e.printStackTrace();}}@Overridepublic void measureSize(int width, int height) {super.measureSize(width, height);}
　　//拍照@Overridepublic void takePicture() {super.takePicture();camera.takePicture(new Camera.ShutterCallback() {@Override　　　　　　//原始图像数据回调public void onShutter() {}}, new Camera.PictureCallback() {@Override　　　　　　//展示图像数据的回调public void onPictureTaken(byte[] data, Camera camera) {}}, new Camera.PictureCallback() {@Override　　　　　　//JPEG图像数据的回调public void onPictureTaken(byte[] data, Camera camera) {if(pictureCallback!=null){pictureCallback.onPictureTaken(data,displayScale);}}});}
}