二维码生成与读取

生成QR图    
private void createImage() {
        try {
            // 需要引入core包
            QRCodeWriter writer = new QRCodeWriter();

            String text = qr_text.getText().toString();

            Log.i(TAG, "生成的文本：" + text);
            if (text == null || "".equals(text) || text.length() < 1) {
                return;
            }

            // 把输入的文本转为二维码
            BitMatrix martix = writer.encode(text, BarcodeFormat.QR_CODE,
                    QR_WIDTH, QR_HEIGHT);

            System.out.println("w:" + martix.getWidth() + "h:"
                    + martix.getHeight());

            Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
            BitMatrix bitMatrix = new QRCodeWriter().encode(text,
                    BarcodeFormat.QR_CODE, QR_WIDTH, QR_HEIGHT, hints);
            int[] pixels = new int[QR_WIDTH * QR_HEIGHT];
            for (int y = 0; y < QR_HEIGHT; y++) {
                for (int x = 0; x < QR_WIDTH; x++) {
                    if (bitMatrix.get(x, y)) {
                        pixels[y * QR_WIDTH + x] = 0xff000000;
                    } else {
                        pixels[y * QR_WIDTH + x] = 0xffffffff;
                    }

                }
            }

            Bitmap bitmap = Bitmap.createBitmap(QR_WIDTH, QR_HEIGHT,
                    Bitmap.Config.ARGB_8888);

            bitmap.setPixels(pixels, 0, QR_WIDTH, 0, 0, QR_WIDTH, QR_HEIGHT);
            qr_image.setImageBitmap(bitmap);

        } catch (WriterException e) {
            e.printStackTrace();
        }
    }

    解析QR图片
    private void scanningImage() {

        Map<DecodeHintType, String> hints = new HashMap<DecodeHintType, String>();
        hints.put(DecodeHintType.CHARACTER_SET, "utf-8");

        // 获得待解析的图片
        Bitmap bitmap = ((BitmapDrawable) qr_image.getDrawable()).getBitmap();
        RGBLuminanceSource source = new RGBLuminanceSource(bitmap);
        BinaryBitmap bitmap1 = new BinaryBitmap(new HybridBinarizer(source));
        QRCodeReader reader = new QRCodeReader();
        Result result;
        try {
            result = reader.decode(bitmap1, hints);
            // 得到解析后的文字
            qr_result.setText(result.getText());
        } catch (NotFoundException e) {
            e.printStackTrace();
        } catch (ChecksumException e) {
            e.printStackTrace();
        } catch (FormatException e) {
            e.printStackTrace();
        }
    }

/**
	 * 用字符串生成二维码
	 * @param str
	 * @author zhouzhe@lenovo-cw.com
         * zxing是google的一个开源二维码项目,目前基本上和二维码打交道的东西,都会用到它. 最近项
         *  目中用到了android手机需要根据提供的字符串生成二维码图片,之前用zxing做过二维码解码,
         * 编码还没做过,看了一些demo都是用到了zxing的j2se包的内容,这个在android或者其他平台
         * 上显然无法实现,所以我们要利用zxing生成二维矩阵,然后根据android平台的提供的api来
         * 生成图片.
         * 这一切,需要zxing的core包,在zxing 1.6下测试通过.
	 * @return
	 * @throws WriterException
	 */
	public Bitmap Create2DCode(String str) throws WriterException {
		//生成二维矩阵,编码时指定大小,不要生成了图片以后再进行缩放,这样会模糊导致识别失败
		BitMatrix matrix = new MultiFormatWriter().encode(str,BarcodeFormat.QR_CODE, 300, 300);
		int width = matrix.getWidth();
		int height = matrix.getHeight();
		//二维矩阵转为一维像素数组,也就是一直横着排了
		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] = 0xff000000;
				}
				
			}
		}
		
		Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
		//通过像素数组生成bitmap,具体参考api
		bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
		return bitmap;
	}