Android Camera打开流程详解

Camera open process
一.上层调用
CameraActivity.java (src\com\android\camera) 101442 2015-7-23
@Override
    public void onCreate(Bundle icicle) {
    ............
        mCameraDeviceCtrl.openCamera();
}


CameraDeviceCtrl.java (src\com\android\camera\bridge) 64825 2015-10-16
public void openCamera() {
        Log.d(TAG, "[openCamera] cameraState:" + getCameraState());//D/CAM_ori/CameraDeviceCtrl( 3621): [openCamera] cameraState:STATE_OPENING_CAMERA
        if (getCameraState() != CameraState.STATE_CAMERA_CLOSED) {
            return;
        }
        mCameraStartUpThread.openCamera();
        setCameraState(CameraState.STATE_OPENING_CAMERA);
    }

    public synchronized void openCamera() {
            mOpenCamera = true;
            mCancel = false;
            notifyAll();
    }

private int openCamera(boolean isDualCamera) {
            Log.i(TAG, "[openCamera] isDualCamera:" + isDualCamera + "mCameraId:" + mCameraId);//I/CAM_ori/CameraDeviceCtrl( 3621): [openCamera] isDualCamera:falsemCameraId:0
            int cameraId = getPreferredCameraId(mPreferences);
            if (mCameraId != cameraId) {

                SettingUtils.writePreferredCameraId(mPreferences, mCameraId);
            }
            try {
                // TODO will delete this
                if (mCameraActivity.isNeedOpenStereoCamera()) {
                    String ROPERTY_KEY_CLIENT_APPMODE = "client.appmode";
                    String APP_MODE_NAME_MTK_DUAL_CAMERA = "MtkStereo";
                    android.hardware.Camera.setProperty(ROPERTY_KEY_CLIENT_APPMODE,
                            APP_MODE_NAME_MTK_DUAL_CAMERA);
                }
                Util.openCamera(mCameraActivity, isDualCamera, mCameraId);
                mCameraDevice = CameraHolder.instance().getCameraProxy(mCameraId);
                mTopCamId = (mCameraId == CameraHolder.instance().getBackCameraId()) ? CameraHolder
                        .instance().getFrontCameraId() : CameraHolder.instance().getBackCameraId();
                mTopCamDevice = CameraHolder.instance().getCameraProxy(mTopCamId);
                // M: added for mock camera
                prepareMockCamera();
                // mIsCameraOpened = true;
            } catch (CameraHardwareException e) {
                Log.i(TAG, "[openCamera]CameraHardwareException e:" + e);
                mIsOpenCameraFail = true;
                mMainHandler.sendEmptyMessage(MSG_OPEN_CAMERA_FAIL);
                return CAMERA_HARDWARE_EXCEPTION;
            } catch (CameraDisabledException e) {
                Log.i(TAG, "[openCamera]CameraDisabledException e:" + e);
                mIsOpenCameraFail = true;
                mMainHandler.sendEmptyMessage(MSG_OPEN_CAMERA_DISABLED);
                return CAMERA_DISABLED_EXCEPTION;
            }
            mParameters = (mCameraDevice == null) ? null : CameraHolder.instance()