现在扫码相同离线订单时不作处理并播放提示音

app/src/main/java/com/bgycc/smartcanteen/activity/MainActivity.java

@@ -222,7 +222,12 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
                     qrCodeText.setText(msg);
                     break;
                 case QRCodeState.FAILED:
+                    String failedText = event.getMessage();
+                    if (TextUtils.isEmpty(failedText)) {
                         TTSHelper.speak("无效二维码");
+                    } else {
+                        TTSHelper.speak(failedText);
+                    }
                     qrCodeViewModel.scan();
                     break;
                 case QRCodeState.ILLEGAL:

app/src/main/java/com/bgycc/smartcanteen/entity/PayData.java

@@ -52,6 +52,14 @@ public class PayData {
         return payState == PAY_SUCCESS;
     }
 
+    public boolean failed() {
+        return payState == PAY_FAILED;
+    }
+
+    public boolean offline() {
+        return payState == PAY_OFFLINE;
+    }
+
     public void paySuccess() {
         payState = PAY_SUCCESS;
     }

app/src/main/java/com/bgycc/smartcanteen/viewModel/QRCodeViewModel.java

@@ -119,6 +119,13 @@ public class QRCodeViewModel extends ViewModel {
         }
 
         PayData newPay = new PayData(deviceSN, scanData, terminalType);
+        // 扫描到的二维码，先检查是否已存在该订单(若标记“支付失败”，则认为该订单不存在)
+        PayData existsPay = payDataRepository.queryPayDataByPayCode(scanData);
+        if (existsPay != null && !existsPay.failed()) {
+            // 存在相同订单时不作处理
+            qrCodeState.postValue(new QRCodeState(QRCodeState.FAILED, "请不要重复扫码"));
+            return;
+        }
         // 扫描到的二维码保存到数据库
         long lastInsertId = payDataRepository.insertPayData(newPay);
         if (lastInsertId == -1) {