The plugin allows you to scan and decode various types of barcodes, including QR codes and UPC codes. For a complete list of supported barcodes, see BarcodeFormat. The scanning is done directly on the device and does not require a network connection. The plugin supports Android and iOS, and it allows multiple barcodes to be scanned at once. It also has torch and autofocus support, and an optional ready-to-use interface without the need for webview customizations.
Great job!
But it seems me a bit unstable.
I couldn’t run it using --livereload and the scann doesn’t work.
Please, which version of NodeJS, Ionic and Capacitor do you recommend to have a best result?
Thanks!
Hi. Could you help me again. I tried using version 0.0.3 and it works however I have an error for samsung S21.
Android version 13
When I try to scan a barcode I have an error
scan failed.
com.google.mlkit.common.MlKitException: Failed to scan code.
at com.google.mlkit.vision.codescanner.internal.zze.zzc(com.google.android.gms:play-services-code-scanner@@16.0.0-beta3:4)
at com.google.mlkit.vision.codescanner.internal.zzf.onActivityResult(com.google.android.gms:play-services-code-scanner@@16.0.0-beta3:5)
at androidx.activity.result.ActivityResultRegistry.doDispatch(ActivityResultRegistry.java:409)
at androidx.activity.result.ActivityResultRegistry.dispatchResult(ActivityResultRegistry.java:366)
at androidx.activity.ComponentActivity.onActivityResult(ComponentActivity.java:712)
at android.app.Activity.dispatchActivityResult(Activity.java:8951)
at android.app.ActivityThread.deliverResults(ActivityThread.java:5987)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:6033)
at android.app.servertransaction.ActivityResultItem.execute(ActivityResultItem.java:67)
at android.app.servertransaction.ActivityTransactionItem.execute(ActivityTransactionItem.java:45)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2574)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:226)
at android.os.Looper.loop(Looper.java:313)
at android.app.ActivityThread.main(ActivityThread.java:8757)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1067)
Probably something happens here
static void zzc(@Nullable Barcode var0, int var1) {
Pair var2 = (Pair)zza.getAndSet((Object)null);
if (var2 != null) {
if (var0 != null) {
((TaskCompletionSource)var2.first).setResult(var0);
} else if (var1 == 201) {
((CancellationTokenSource)var2.second).cancel();
} else {
Object var3 = var2.first;
TaskCompletionSource var4 = (TaskCompletionSource)var3;
MlKitException var5 = new MlKitException("Failed to scan code.", var1);
var4.setException(var5);
}
} else {
Log.e("GmsBarcodeScannerImpl", "Scanning task source doesn't exist when setting back result.");
}
}
Also tried using iPhone 11 and Samsung A70 and it works for both
There is a workaround mentioned in this thread. I will give it a try as soon as i have some time. If it works, I will release an update. I have created a new GitHub issue for this: bug: · Issue #38 · capawesome-team/capacitor-mlkit · GitHub
In the meantime, you can use the startScan(…) method. This works without any problems.
startScan failed.
java.lang.NullPointerException: Attempt to invoke virtual method ‘androidx.camera.core.Preview$SurfaceProvider androidx.camera.view.PreviewView.getSurfaceProvider()’ on a null object reference
at io.capawesome.capacitorjs.plugins.mlkit.barcodescanning.BarcodeScanner.lambda$startScan$0$io-capawesome-capacitorjs-plugins-mlkit-barcodescanning-BarcodeScanner(BarcodeScanner.java:100)
at io.capawesome.capacitorjs.plugins.mlkit.barcodescanning.BarcodeScanner$$ExternalSyntheticLambda8.run(Unknown Source:8)
at android.os.Handler.handleCallback(Handler.java:942)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:226)
at android.os.Looper.loop(Looper.java:313)
at android.app.ActivityThread.main(ActivityThread.java:8757)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1067)
message: “Attempt to invoke virtual method ‘androidx.camera.core.Preview$SurfaceProvider androidx.camera.view.PreviewView.getSurfaceProvider()’ on a null object reference”
startScan failed.
java.lang.NullPointerException: Attempt to invoke virtual method ‘androidx.camera.core.Preview$SurfaceProvider androidx.camera.view.PreviewView.getSurfaceProvider()’ on a null object reference
at io.capawesome.capacitorjs.plugins.mlkit.barcodescanning.BarcodeScanner.lambda$startScan$0$io-capawesome-capacitorjs-plugins-mlkit-barcodescanning-BarcodeScanner(BarcodeScanner.java:100)
at io.capawesome.capacitorjs.plugins.mlkit.barcodescanning.BarcodeScanner$$ExternalSyntheticLambda8.run(Unknown Source:8)
at android.os.Handler.handleCallback(Handler.java:942)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:226)
at android.os.Looper.loop(Looper.java:313)
at android.app.ActivityThread.main(ActivityThread.java:8757)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1067)
it shows me this method
public void startScan(ScanSettings scanSettings, StartScanResultCallback callback) {
// Stop the camera if running
stopScan();
// Hide WebView background
hideWebViewBackground();
this.scanSettings = scanSettings;
BarcodeScannerOptions options = buildBarcodeScannerOptions(scanSettings);
barcodeScannerInstance = BarcodeScanning.getClient(options);
ImageAnalysis imageAnalysis = new ImageAnalysis.Builder().setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST).build();
imageAnalysis.setAnalyzer(ContextCompat.getMainExecutor(plugin.getContext()), this);
ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(plugin.getContext());
cameraProviderFuture.addListener(
() -> {
try {
processCameraProvider = cameraProviderFuture.get();
CameraSelector cameraSelector = new CameraSelector.Builder().requireLensFacing(this.scanSettings.lensFacing).build();
previewView = plugin.getActivity().findViewById(R.id.preview_view);
Preview preview = new Preview.Builder().build();
preview.setSurfaceProvider(previewView.getSurfaceProvider());// This place shows the error
// Start the camera
camera =
processCameraProvider.bindToLifecycle((LifecycleOwner) plugin.getContext(), cameraSelector, preview, imageAnalysis);
callback.success();
} catch (Exception exception) {
callback.error(exception);
}
},
ContextCompat.getMainExecutor(plugin.getContext())
);
}
Samsung S21,
Android version 13
“@capacitor-mlkit/barcode-scanning”: “^0.0.3”
