Zxing兼容2.3等低版本

需要修改的地方

1.InactivityTimer.java

public synchronized void onActivity() {

　　　...

　　if (Build.VERSION.SDK_INT < 11) {
        inactivityTask.execute();
    }else{
        inactivityTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
    }

}

2.AutoFocusManager.java

public synchronized void onAutoFocus(boolean success, Camera theCamera) {
        if (active) {
            outstandingTask = new AutoFocusTask();
            if (Build.VERSION.SDK_INT < 11) {
                outstandingTask.execute();
            } else {
                outstandingTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
            }
        }
    }

3.CameraManager.java （报W/CaptureActivity(24188): java.io.IOException: setPreviewDisplay failed异常，需要给SurfaceHolder设置type,   surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);）

　　@Override
    protected void onResume() {

　　　　...

　　　SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
        SurfaceHolder surfaceHolder = surfaceView.getHolder();
        if (Build.VERSION.SDK_INT < 11) {
            surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

　　}

　　@Override
    public void surfaceCreated(SurfaceHolder holder) {
        if (holder == null) {
            Log.e(TAG, "*** WARNING *** surfaceCreated() gave us a null surface!");
        }else{
            if (Build.VERSION.SDK_INT < 11) {
                holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
            }
        }
        if (!hasSurface) {
            hasSurface = true;
            initCamera(holder);
        }
    }

4.CameraConfigurationManager.java （报 java.lang.NoSuchMethodError: android.view.Display.getSize）

void initFromCameraParameters(Camera camera) {
        Camera.Parameters parameters = camera.getParameters();
        WindowManager manager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        Display display = manager.getDefaultDisplay();
        Point theScreenResolution = new Point();
        if (Build.VERSION.SDK_INT < 13) {
            theScreenResolution.x = display.getWidth();
            theScreenResolution.y = display.getHeight();
        } else {
            display.getSize(theScreenResolution);
        }
        screenResolution = theScreenResolution;
        Log.i(TAG, "Screen resolution: " + screenResolution);
        cameraResolution = findBestPreviewSizeValue(parameters, screenResolution);
        Log.i(TAG, "Camera resolution: " + cameraResolution);
    }