Android中二维码的扫描和生成(使用zxing库)

public class CreateUtil { //String codestring：要生成二维码的字符串 // int width：二维码图片的宽度 // int height：二维码图片的高度 public static Bitmap createQRCode(String codestring,int width,int height){ try { //首先判断参数的合法性，要求字符串内容不能为空或图片长宽必须大于0 if (TextUtils.isEmpty(codestring)||width<=0||height<=0){ return null; } //设置二维码的相关参数，生成BitMatrix（位矩阵）对象 Hashtable hashtable=new Hashtable<>(); hashtable.put(EncodeHintType.CHARACTER_SET,"utf-8");  //设置字符转码格式 hashtable.put(EncodeHintType.ERROR_CORRECTION,"H");   //设置容错级别 hashtable.put(EncodeHintType.MARGIN,"2"); //设置空白边距 //encode需要抛出和处理异常 BitMatrix bitMatrix=new QRCodeWriter().encode(codestring, BarcodeFormat.QR_CODE,width,height,hashtable); //再创建像素数组，并根据位矩阵为数组元素赋颜色值 int[] pixel=new int[width*width]; for (int h=0;h

//点击开始生成按钮监听事件 startBt1.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String input=inputEt.getText().toString();  //获取用户输入的字符串 //调用CreateUtil类生成二维码后显示在界面上 contentIv.setImageBitmap(CreateUtil.createQRCode(input,contentIv.getWidth(),contentIv.getHeight())); } });

        //开始扫描按钮点击事件监听 startBt2.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { scanQRCode(); } }); //实现扫描二维码的方法 private void scanQRCode() { //申请相机权限 if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, Constant.REQ_PERM_CAMERA); return; } //申请文件(相册)读写权限 if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, Constant.REQ_PERM_EXTERNAL_STORAGE); return; } //二维码扫码 //然后通过Intent机制启动zxing框架的CaptureActivity，请求返回结果 Intent intent = new Intent(this, CaptureActivity.class); startActivityForResult(intent, Constant.REQ_QR_CODE); } @Override protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) { super.onActivityResult(requestCode, resultCode, data); //扫描结果回调 if (requestCode == Constant.REQ_QR_CODE && resultCode == RESULT_OK) { Bundle bundle = data.getExtras(); String scanResult = bundle.getString(Constant.INTENT_EXTRA_KEY_QR_SCAN); //将扫描出的信息显示出来 resultTv.setText(scanResult); } } @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { super.onRequestPermissionsResult(requestCode, permissions, grantResults); switch (requestCode){ case Constant.REQ_PERM_CAMERA: //摄像头权限申请 if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { //获得授权 scanQRCode(); } else { //被禁止授权 Toast.makeText(this, "请至权限中心打开本应用的相机访问权限", Toast.LENGTH_LONG).show(); } break; case Constant.REQ_PERM_EXTERNAL_STORAGE: //文件读写权限申请 if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { //获得授权 scanQRCode(); } else { //被禁止授权 Toast.makeText(this, "请至权限中心打开本应用的文件读写权限", Toast.LENGTH_LONG).show(); } break; } } }

implementation 'com.google.zxing:core:3.3.3'

 public static com.google.zxing.Result[] decodeQR(Bitmap srcBitmap) { com.google.zxing.Result[] result = null; if (srcBitmap != null) { int width = srcBitmap.getWidth(); int height = srcBitmap.getHeight(); int[] pixels = new int[width * height]; srcBitmap.getPixels(pixels, 0, width, 0, 0, width, height); // 新建一个RGBLuminanceSource对象 RGBLuminanceSource source = new RGBLuminanceSource(width, height, pixels); // 将图片转换成二进制图片 BinaryBitmap binaryBitmap = new BinaryBitmap(new GlobalHistogramBinarizer(source)); QRCodeMultiReader reader = new QRCodeMultiReader();// 初始化解析对象 try { result = reader.decodeMultiple(binaryBitmap, CodeHintsUtils.getDefaultDecodeHints());// 解析获取一个Result数组 } catch (NotFoundException e) { e.printStackTrace(); } } return result; }