[AndroidStudio]zxing 库的使用

环境：androidstudio2.3.2
zxing git源码路径 https://github.com/zxing/zxing

AndroidStudio引用该库：
dependencies {
compile fileTree(dir: ‘libs’, include: [‘*.jar’])
compile ‘com.android.support:appcompat-v7:25.3.1’
compile ‘com.google.zxing:core:3.2.1’
}

使用代码

/**
 * 生成QRCode二维码
 *
 * @param data
 * @param size qr二维码为正方形码，宽高一致
 * @return
 */
private Bitmap generateQRCodeBitmap(String data, int size) {
    return generateQRCodeBitmap(data, size, size);
}

private Bitmap generateQRCodeBitmap(String data, int width, int height) {
    QRCodeWriter qrCodeWriter = new QRCodeWriter();
    Map hints = new HashMap<>();
    //编码
    hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
    //容错率
    hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.Q);
    int margin = 1;  //自定义白边边框宽度
    //二维码边框宽度
    hints.put(EncodeHintType.MARGIN, margin);
    try {
        BitMatrix encode = qrCodeWriter.encode(data, BarcodeFormat.QR_CODE, width, height, hints);
        int[] pixels = new int[width * height];
        for (int i = 0; i < height; i++) {
            for (int j = 0; j < width; j++) {
                if (encode.get(j, i)) {
                    pixels[i * width + j] = 0x00000000;
                } else {
                    pixels[i * width + j] = 0xffffffff;
                }
            }
        }
        return Bitmap.createBitmap(pixels, 0, width, width, height, Bitmap.Config.RGB_565);
    } catch (WriterException e) {
        e.printStackTrace();
    }
    return null;
}

其他：
解析二维码，参考：http://blog.csdn.net/xiaanming/article/details/10163203

去除白边或进行放缩：http://blog.csdn.net/jdsjlzx/article/details/45268815