Android onReadCode is only fired once

[Epick362]

Describe the bug Barcode scanning callback only runs once on Android. Works just fine on iOS. Library version: 12.1.0

To Reproduce Steps to reproduce the behavior:

1. Have a screen with Camera component like so

       <Camera
         style={{
           flex: 1,
           backgroundColor: 'transparent',
         }}
         cameraType={CameraType.Back}
         flashMode={'auto'}
         focusMode={'on'}
         zoomMode={'on'}
         scanBarcode={true}
         onReadCode={onScan}
       />

2. Scan a QR/barcode
3. Callback executed
4. wait a few seconds
5. try scanning any other QR code
6. Callback not executed

Expected behavior Callback gets executed multiple times.

Smartphone (please complete the following information):

• Device: Samsung Galaxy A12
• OS: Android 11

[Epick362]

I tried downgrading and this issue is happening since version 10.0.0

[DibyajyotiMishra]

Never found that happening. Can you describe further ?

[Epick362]

Callback function onScan() passed to prop onReadCode is only fired on the first detection of a QR code and then stops working. This is happening only on Android devices. After downgrading to 10.0.0 the callback works as expected multiple times.

[Maxth]

We are experiencing this as well. Same smartphone model Samsung Galaxy A12.

[hardikcc]

Anyone able to solve this issue?

[saaymeen]

Experiencing this issue as well, Galaxy Note 9 & S21.

[hardikcc]

Anyone had any luck on this?

[SteveWatson75]

Also experiencing this, tried to force reload the component and set a navigation focus listener but still doesn't work

https://user-images.githubusercontent.com/88657039/196120702-8e94f64e-d40d-487d-a192-6575e1587dc6.mp4

[DamianJudek]

Hi guys, I think I found some workaround. In my case the onReadCode callback was also fired once. I'm using React Navigation and I have a barcode scanning feature on one screen. So I decided to use the useIsFocused hook and unmount the camera when I leave the screen. Now the scan works as expected. It seems like Camera Screen lost the reference to onReadCode callback after scanning/refreshing the state. Maybe this will be a clue that will help you.

export const Camera = ({navigation}: any) => {
  const isFocused = useIsFocused();
  const [barcode, setBarcode] = useState<string>('');

  const handleBarcodeScan = (e: any) => {
    setBarcode(e.nativeEvent.codeStringValue);
  };

  return isFocused ? (
    <Layout>
      <CameraContainer>
        <CameraScreen
          style={{flex: 1}}
          scanBarcode={true}
          onReadCode={handleBarcodeScan}
          showFrame={true}
          laserColor="darkorange"
          frameColor="darkorange"
          hideControls={true}
        />
      </CameraContainer>
    </Layout>
  ) : null;
};

[danyzor]

@DamianJudek , worked for me, thanks a lot! :)

[Epick362]

Thanks @DamianJudek! This seems like a good workaround in the meantime.