[移动开发]Android二维码生成与识别

导入依赖
implememtation 'com.google.zxing:core:3.4.1'

public class QrCodeUtil {
	public static String decode(Context context, Uri uri) {
		try {
			Bitmap bmp= MediaStore.Images.Media.getBitmap(context.getContentResolver(), uri);
			return decode(bmp);
		} catch (Exception e) {
			return "";
		}
	}

	public static String decode(Bitmap bmp) {
		Hashtable<DecodeHintType,String> hints=new Hashtable<>();
		hints.put(DecodeHintType.CHARACTER_SET, "utf-8");

		try {
			int width=bmp.getWidth();
			int height=bmp.getHeight();
			int[] pixels=new int[width * height];
			bmp.getPixels(pixels, 0, width, 0, 0, width, height);

			RGBLuminanceSource source=new RGBLuminanceSource(width, height, pixels);
			return new MultiFormatReader().decode(new BinaryBitmap(new HybridBinarizer(source)), hints).getText();
		} catch (Exception e) {
			return "";
		}
	}

	public static Bitmap generate(CharSequence content, int width, int height) {
		if (TextUtils.isEmpty(content)) {
			return null;
		}
		Hashtable<EncodeHintType,String> hints=new Hashtable<>();
		hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
		try {
			BitMatrix bitMatrix=new QRCodeWriter().encode(content.toString(), 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 (Exception e) {
			return null;
		}
	}
}