用ZXING生成二维码的工具类（可以去掉白边，添加logo）

===========================用ZXING生成二维码的工具类（可以去掉白边，添加logo）==========================

/**

 * @auther gjc

 * @since 2016/12/27.

 */

public class CreateCodeUtil {

    public static Bitmap createQRImage(String str, int width, int height, Bitmap logoBm) {

        try {

            Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();

            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");

            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);

//            hints.put(EncodeHintType.MARGIN, 1);

            BitMatrix matrix = new QRCodeWriter().encode(str, BarcodeFormat.QR_CODE, width, height);

            matrix = deleteWhite(matrix);//删除白边

            width = matrix.getWidth();

            height = matrix.getHeight();

            int[] pixels = new int[width * height];

            for (int y = 0; y < height; y++) {

                for (int x = 0; x < width; x++) {

                    if (matrix.get(x, y)) {

                        pixels[y * width + x] = Color.BLACK;

                    } else {

                        pixels[y * width + x] = Color.WHITE;

                    }

                }

            }

            Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);

            bitmap.setPixels(pixels, 0, width, 0, 0, width, height);

            bitmap = addLogo(bitmap, logoBm);

            return bitmap;

        } catch (Exception e) {

            return null;

        }

    }

    /**

     * 删除白边

     * */

    private static BitMatrix deleteWhite(BitMatrix matrix) {

        int[] rec = matrix.getEnclosingRectangle();

        int resWidth = rec[2] + 1;

        int resHeight = rec[3] + 1;

        BitMatrix resMatrix = new BitMatrix(resWidth, resHeight);

        resMatrix.clear();

        for (int i = 0; i < resWidth; i++) {

            for (int j = 0; j < resHeight; j++) {

                if (matrix.get(i + rec[0], j + rec[1]))

                    resMatrix.set(i, j);

            }

        }

        return resMatrix;

    }

    /**

     * 在二维码中间添加Logo图案

     */

    private static Bitmap addLogo(Bitmap src, Bitmap logo) {

        if (src == null) {

            return null;

        }

        if (logo == null) {

            return src;

        }

        //获取图片的宽高

        int srcWidth = src.getWidth();

        int srcHeight = src.getHeight();

        int logoWidth = logo.getWidth();

        int logoHeight = logo.getHeight();

        if (srcWidth == 0 || srcHeight == 0) {

            return null;

        }

        if (logoWidth == 0 || logoHeight == 0) {

            return src;

        }

        //logo大小为二维码整体大小的1/5

        float scaleFactor = srcWidth * 1.0f / 5 / logoWidth;

        Bitmap bitmap = Bitmap.createBitmap(srcWidth, srcHeight, Bitmap.Config.ARGB_8888);

        try {

            Canvas canvas = new Canvas(bitmap);

            canvas.drawBitmap(src, 0, 0, null);

            canvas.scale(scaleFactor, scaleFactor, srcWidth / 2, srcHeight / 2);

            canvas.drawBitmap(logo, (srcWidth - logoWidth) / 2, (srcHeight - logoHeight) / 2, null);

            canvas.save(Canvas.ALL_SAVE_FLAG);

            canvas.restore();

        } catch (Exception e) {

            bitmap = null;

            e.getStackTrace();

        }

        return bitmap;

    }

}