最近得到了一个需求，在后台拍照并保存

public void onTakePhotoClicked() {

final SurfaceView preview = new SurfaceView(this);

SurfaceHolder holder = preview.getHolder();

// deprecated setting, but required on Android versions prior to 3.0

holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

holder.addCallback(new SurfaceHolder.Callback() {

@Override

//The preview must happen at or after this point or takePicture fails

public void surfaceCreated(SurfaceHolder holder) {

Log.d(TAG, "Surface created");

camera = null;

try {

camera = Camera.open(Camera.CameraInfo.CAMERA_FACING_BACK);

Log.d(TAG, "Opened camera");

try {

camera.setPreviewDisplay(holder);

} catch (IOException e) {

throw new RuntimeException(e);

}

camera.startPreview();

Log.d(TAG, "Started preview");

//延时拍照

ThreadUtils.postOnUiThreadDelayed(new Runnable() {

@Override

public void run() {

Log.e("zgj","开始拍照");

camera.takePicture(null, null, CameraService.this);

}

},5000);

} catch (Exception e) {

if (camera != null)

camera.release();

throw new RuntimeException(e);

}

}

@Override

public void surfaceDestroyed(SurfaceHolder holder) {}

@Override

public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {}

});

WindowManager wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE);

WindowManager.LayoutParams params = new WindowManager.LayoutParams(

1, 1, //Must be at least 1x1

WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,

0,

//Don't know if this is a safe default

PixelFormat.UNKNOWN);

//Don't set the preview visibility to GONE or INVISIBLE

wm.addView(preview, params);

}

@Override

public void onPictureTaken(byte[] bytes, Camera camera) {

Log.e("zgj", "拍照结束");

File pictureDir = Environment.getExternalStorageDirectory();

if (pictureDir == null) {

Log.d("zgj",

"Error creating media file, check storage permissions!");

return;

}

try {

String pictureName = "ssss.png";

File file = new File(pictureDir + "/pic/");

if (!file.exists()) {

file.mkdir();

}

file = new File(pictureDir + "/pic/" + pictureName);

FileOutputStream fos = new FileOutputStream(file);

fos.write(bytes);

fos.close();

} catch (FileNotFoundException e) {

Log.d("zgj", "File not found: " + e.getMessage());

} catch (IOException e) {

Log.d("zgj", "Error accessing file: " + e.getMessage());

}

}