Google Vision Api Camera preview issue

[Maheswaran140387]

I am facing the below issue while using the google vision api for scanning qr code.

Detector processor must first be set with setProcessor in order to receive detection results. site:stackoverflow.com

can you please help me on this?

The camera preview is not opening at the first time, also I am unable to update the UI once the scan is successful.

Below is my code

{

private BusinessModel bmodel;
private DisplayMetrics displaymetrics;
private boolean is7InchTablet;
private SurfaceView surfaceView;
private BarcodeDetector barcodeDetector;
private CameraSource cameraSource;
private Button startVisit,btn_scan;
private Spinner reasonSpinnerForScanFailed,qrcodeTypeSpinner;
private boolean isScanSuccussfull;
private ArrayAdapter<ReasonMaster> reasonAdapterForScanFailed,adapterqrtype;
private String type = "0",reason = "0";
private SparseArray<Barcode> response;
private TextView tvresult;
private AlertDialog.Builder builder;
private AlertDialog alertDialog;
private static String TAG = "XCYCLE";
private boolean isCameraEnabled;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_qrcodescan);

    bmodel = (BusinessModel) getApplicationContext();
    bmodel.setContext(this);
    Log.i(TAG, "onCreate()");
    overridePendingTransition(R.anim.trans_left_in, R.anim.trans_left_out);
    displaymetrics = new DisplayMetrics();
    getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    is7InchTablet = this.getResources().getConfiguration().isLayoutSizeAtLeast(SCREENLAYOUT_SIZE_LARGE);

    Toolbar toolbar = findViewById(R.id.toolbar);
    if (toolbar != null) {
        setSupportActionBar(toolbar);
        if (getSupportActionBar() != null) {
            getSupportActionBar().setDisplayShowTitleEnabled(false);
            setScreenTitle("QR Code Scan");
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            getSupportActionBar().setDisplayShowHomeEnabled(true);
        }
    }

    startVisit = (Button)findViewById(R.id.save);
    btn_scan = (Button)findViewById(R.id.scan);
    tvresult = (TextView)findViewById(R.id.tvresult);
    surfaceView = (SurfaceView)findViewById(R.id.cameraview);
    reasonSpinnerForScanFailed = (Spinner)findViewById(R.id.reasonspinnerforscanfailed);
    qrcodeTypeSpinner = (Spinner)findViewById(R.id.qrcodetypespinner);
    startVisit.setOnClickListener(this);
    btn_scan.setOnClickListener(this);
    if(getIntent().getExtras() != null)
        type = getIntent().getExtras().getString("type");

    if(checkAndRequestPermissionAtRunTime(2))
        startScan();
}

@Override
protected void onStart() {
    super.onStart();
    Log.i(TAG, "onStart()");
    loadTypeSpinner();
    loadReasonSpinner();

    qrcodeTypeSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            ReasonMaster qrtype = (ReasonMaster) adapterView.getSelectedItem();
            type = qrtype.getReasonID();
        }

        @Override
        public void onNothingSelected(AdapterView<?> adapterView) {

        }
    });

    reasonSpinnerForScanFailed.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
            ReasonMaster reasonMaster = (ReasonMaster) adapterView.getSelectedItem();
            reason = reasonMaster.getReasonID();
        }

        @Override
        public void onNothingSelected(AdapterView<?> adapterView) {

        }
    });

}

private void startScan() {

    try {

        barcodeDetector = new BarcodeDetector.Builder(this).setBarcodeFormats(Barcode.QR_CODE).build();
        cameraSource = new CameraSource.Builder(QRCodeScan.this, barcodeDetector)
                .setRequestedPreviewSize(400, 400)
                .build();

        surfaceView.getHolder().addCallback(new SurfaceHolder.Callback2() {
            @Override
            public void surfaceRedrawNeeded(SurfaceHolder surfaceHolder) {
                Toast.makeText(QRCodeScan.this, "surfaceRedrawNeeded()", Toast.LENGTH_LONG).show();
            }

            @Override
            public void surfaceCreated(SurfaceHolder surfaceHolder) {
                try {
                    Toast.makeText(QRCodeScan.this, "surfaceCreated()", Toast.LENGTH_LONG).show();
                    cameraSource.start(surfaceView.getHolder());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            @Override
            public void surfaceChanged(SurfaceHolder surfaceHolder, int i, int i1, int i2) {
                Toast.makeText(QRCodeScan.this, "surfaceChanged()", Toast.LENGTH_LONG).show();
            }

            @Override
            public void surfaceDestroyed(SurfaceHolder surfaceHolder) {
                Toast.makeText(QRCodeScan.this, "surfaceDestroyed()", Toast.LENGTH_LONG).show();
                cameraSource.stop();
            }
        });

        barcodeDetector.setProcessor(new Detector.Processor<Barcode>() {
            @Override
            public void release() {
            }

            @Override
            public void receiveDetections(Detector.Detections<Barcode> detections) {

                try
                {
                    response = detections.getDetectedItems();
                    if (response != null && response.size() > 0) {
                        barcodeDetector.release();
                        isScanSuccussfull = true;
                        if (validateAndSave()) {
                            moveToHomeScreenTwo();
                        }
                    }
                }catch (Exception e){
                    e.printStackTrace();
                }
            }
        });
    }catch (Exception e){
        e.printStackTrace();
    }
}

@Override
protected void onResume() {
    super.onResume();
    Log.i(TAG, "onResume()");
    checkAndRequestPermissionAtRunTime(2);
    int permissionStatus = ContextCompat.checkSelfPermission(this,
            Manifest.permission.CAMERA);
    if (permissionStatus == PackageManager.PERMISSION_GRANTED) {
        startScan();
    } else {
        Toast.makeText(this,
                getResources().getString(R.string.permission_enable_msg)
                        + " " + getResources().getString(R.string.permission_camera)
                , Toast.LENGTH_LONG).show();
    }
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();
    if (id == android.R.id.home) {
        startActivity(new Intent(this, ProfileActivity.class));
        overridePendingTransition(R.anim.trans_right_in, R.anim.trans_right_out);
        finish();
    }
    return super.onOptionsItemSelected(item);
}

@Override
public void onClick(View view) {
    switch (view.getId()) {

        case R.id.save: {
            if (type.equals("0"))
                Toast.makeText(QRCodeScan.this, getResources().getString(R.string.qr_type_alert), Toast.LENGTH_LONG).show();
            else if(reason.equals("0")){
                Toast.makeText(QRCodeScan.this, getResources().getString(R.string.qr_reason), Toast.LENGTH_LONG).show();
            }else {
                if(validateAndSave())
                    moveToHomeScreenTwo();
                else
                    Toast.makeText(QRCodeScan.this, getResources().getString(R.string.qr_try_again), Toast.LENGTH_LONG).show();
            }
        }

        case R.id.scan: {
            if(checkAndRequestPermissionAtRunTime(2)) {
                if (!type.isEmpty() && !type.equals("0"))
                    startScan();
                else
                    Toast.makeText(QRCodeScan.this, getResources().getString(R.string.qr_type_alert), Toast.LENGTH_LONG).show();
            } else {
                Toast.makeText(this,getResources().getString(R.string.qr_camera_permission),Toast.LENGTH_LONG).show();
            }
        }
    }
}

private void moveToHomeScreenTwo(){
    Toast.makeText(QRCodeScan.this, "Scanned Success", Toast.LENGTH_LONG);
    Intent i = new Intent(this, HomeScreenTwo.class);
    i.putExtra("isLocDialog", true);
    i.putExtra("isMandatoryDialog", true);
    i.setFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    startActivity(i);
    finish();
}

private boolean validateAndSave(){
    String val = "";
    try{
        if(isScanSuccussfull)
            val = response.valueAt(0).displayValue;

        if(bmodel.getAppDataProvider().getRetailMaster().getListOfQRCodeValues() == null)
            return bmodel.qrCodeHelper.saveQRCodeScannedData(type, val, reason , "I");
        else if(!val.isEmpty() && !bmodel.getAppDataProvider().getRetailMaster().getListOfQRCodeValues().contains(val)) {
            isScanSuccussfull = false;
            return false;
        }else
            return bmodel.qrCodeHelper.saveQRCodeScannedData(type, val, reason, "A");
    }catch (Exception e){
        e.printStackTrace();
        return false;
    }
}

private void loadReasonSpinner(){
    try{
        reasonAdapterForScanFailed = new ArrayAdapter<>(this,
                R.layout.call_analysis_spinner_layout);
        reasonAdapterForScanFailed.add(new ReasonMaster(0 + "", getResources().getString(R.string.select_reason)));
        if (bmodel.qrCodeHelper.getQrCodeReasons() != null) {
            for (ReasonMaster temp : bmodel.qrCodeHelper.getQrCodeReasons())
                reasonAdapterForScanFailed.add(temp);

            reasonAdapterForScanFailed.add(new ReasonMaster(-1 + "", getResources().getString(R.string.other_reason)));
        }
        reasonAdapterForScanFailed.setDropDownViewResource(R.layout.call_analysis_spinner_list_item);
        reasonSpinnerForScanFailed.setAdapter(reasonAdapterForScanFailed);
    }catch (Exception e){
        e.printStackTrace();
    }
}

private void loadTypeSpinner(){
    try{
        adapterqrtype = new ArrayAdapter<>(this,
                R.layout.call_analysis_spinner_layout);
        adapterqrtype.add(new ReasonMaster(0 + "", getResources().getString(R.string.qr_hint_type)));
        if (bmodel.qrCodeHelper.getQrCodeReasons() != null) {
            for (ReasonMaster temp : bmodel.qrCodeHelper.getQrCodeTypes())
                adapterqrtype.add(temp);
        }
        adapterqrtype.setDropDownViewResource(R.layout.call_analysis_spinner_list_item);
        qrcodeTypeSpinner.setAdapter(adapterqrtype);
    }catch (Exception e){
        e.printStackTrace();
    }
}

private void openCamera(){
    try{
        cameraSource.start(surfaceView.getHolder());
    }catch (Exception e){
        e.printStackTrace();
    }
}

}

[simiyu1]

This would be better handled in Stackoverflow... it is not an error within the API but with your code. As pointed out when you set the processor

barcodeDetector.setProcessor(new Detector.Processor<Barcode>() 

should be something like

BarcodeDetector barcodeDetector = new BarcodeDetector.Builder(context).build();
        BarcodeTrackerFactory barcodeFactory = new BarcodeTrackerFactory(mGraphicOverlay, this);
        barcodeDetector.setProcessor(
                new MultiProcessor.Builder<>(barcodeFactory).build())

and then to get the results

@Override
    public void onBarcodeDetected(Barcode barcode) {
        //do something with barcode data returned
    }

checkout out this Google sample on this class.