android zxing简单生成二维码

 public static Bitmap createQRImage(String url, final int width, final int height) {
        try {
            // 判断URL合法性
            if (url == null || "".equals(url) || url.length() < 1) {
                return null;
            }
            Hashtable hints = new Hashtable();
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
            // 图像数据转换，使用了矩阵转换
            BitMatrix bitMatrix = new QRCodeWriter().encode(url,
                    BarcodeFormat.QR_CODE, width, height, hints);
            int[] pixels = new int[width * height];
            // 下面这里按照二维码的算法，逐个生成二维码的图片，
            // 两个for循环是图片横列扫描的结果
            for (int y = 0; y < height; y++) {
                for (int x = 0; x < width; x++) {
                    if (bitMatrix.get(x, y)) {
                        pixels[y * width + x] = 0xff000000;
                    } else {
                        pixels[y * width + x] = 0xffffffff;
                    }
                }
            }
            // 生成二维码图片的格式，使用ARGB_8888
            Bitmap bitmap = Bitmap.createBitmap(width, height,
                    Bitmap.Config.ARGB_8888);
            bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
            return bitmap;
        } catch (WriterException e) {
            e.printStackTrace();
        }
        return null;
    }