Barcode Scanner App Android without using ZXing library

Question

Is it possible to create a barcode scanning app that doesn't use the ZXing library as all I have found so far is that the ZXing library requires their Barcode Scanning app but I don't want my app to rely on a third party app.

Thank you

Answer 1

Yes It is possible, You can create your application Using google vision library only. If you use Google Pay, then You can see the qr scanner. I exactly made that, And UI Part with blur effect also. You can go through code as well.

Use this google library in build.gradle in app,

implementation 'com.google.android.gms:play-services-vision:19.0.0'

Then You have to make a UI part like this xml,

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".ui.scanqrcode.BarcodeReaderActivity">

    <include layout="@layout/toolbar_base" />

    <SurfaceView
        android:id="@+id/surfaceView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentStart="true"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true" />

    <TextView
        android:id="@+id/txtBarcodeValue"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginStart="@dimen/activity_horizontal_margin"
        android:layout_marginLeft="@dimen/activity_horizontal_margin"
        android:text="No Barcode Detected"
        android:textColor="@android:color/white"
        android:textSize="20sp" />

    <com.techkyoso.denTech.utils.QRCodeScannerView
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>



    <TextView
        android:id="@+id/txtScanCode"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:text="Scan QR code"
        android:layout_margin="@dimen/activity_vertical_margin_8dp"
        android:layout_above="@id/ivScannerIcon"
        android:textColor="@android:color/white"
        android:textSize="@dimen/text_size_16sp" />


    <ImageView
        android:id="@+id/ivScannerIcon"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="@dimen/activity_horizontal_margin_32dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/icon_qr"
        android:layout_centerHorizontal="true"
        />

</RelativeLayout>

In Ui there is BarCodeScannerView class which I draw on canvas as you can see the code;

public class QRCodeScannerView extends View {
    private Paint mPaint;
    private Paint mStrokePaint;
    private Path mPath = new Path();
    private Point pTopLeft = new Point();
    private Point pBotRight = new Point();

    public QRCodeScannerView(Context context) {
        super(context);
        initPaints();
    }

    public QRCodeScannerView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initPaints();
    }

    public QRCodeScannerView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        initPaints();
    }

    private void initPaints() {
        mPaint = new Paint();
        mPaint.setColor(Color.parseColor("#A6000000"));

        mStrokePaint = new Paint();
        mStrokePaint.setColor(Color.YELLOW);
        mStrokePaint.setStrokeWidth(4);
        mStrokePaint.setStyle(Paint.Style.STROKE);

    }

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        pTopLeft.x = (getWidth() / 13)+10;
        pTopLeft.y = (getHeight() / 4)+20;
        pBotRight.x = (getWidth() - pTopLeft.x)-10;
        pBotRight.y = (getHeight() - pTopLeft.y)-20;

        mPaint.setColor(Color.parseColor("#77000000"));

        //Top Rect
        canvas.drawRect(0, 0, getWidth(), pTopLeft.y, mPaint);

        //Left Rect
        canvas.drawRect(0, pTopLeft.y, pTopLeft.x, pBotRight.y, mPaint);

        //Right Rect
        canvas.drawRect(pBotRight.x, pTopLeft.y, getWidth(), pBotRight.y, mPaint);

        //Bottom rect
        canvas.drawRect(0, pBotRight.y, getWidth(), getHeight(), mPaint);

        //Draw Outer Line drawable
        Drawable d = getResources().getDrawable(R.drawable.scanner_outline, null);
        d.setBounds(pTopLeft.x, pTopLeft.y, pBotRight.x, pBotRight.y);
        d.draw(canvas);

    }
}

Then You have the Activity code where you open your camera and set the barcodeReader variable and get the value. and the code is ;

public class BarcodeReaderActivity extends AppCompatActivity  {

    SurfaceView surfaceView;
    TextView txtBarcodeValue;
    private BarcodeDetector barcodeDetector;
    private CameraSource cameraSource;
    private static final int REQUEST_CAMERA_PERMISSION = 201;
    Button btnAction;
    String intentData = "";
    boolean isEmail = false;
    Toolbar toolBar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_barcode_reader);
        toolBar = findViewById(R.id.toolbar);
        setSupportActionBar(toolBar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setTitle("Scan QR Code");
        toolBar.getNavigationIcon().setColorFilter(getResources().getColor(R.color.white), PorterDuff.Mode.SRC_ATOP);
        toolBar.setNavigationOnClickListener(view -> onBackPressed());
        initViews();
    }

    private void initViews() {
        txtBarcodeValue = findViewById(R.id.txtBarcodeValue);
        surfaceView = findViewById(R.id.surfaceView);

    }

    private void initialiseDetectorsAndSources() {

        Toast.makeText(getApplicationContext(), "Barcode scanner started", Toast.LENGTH_SHORT).show();

        barcodeDetector = new BarcodeDetector.Builder(this)
                .setBarcodeFormats(Barcode.ALL_FORMATS)
                .build();

        cameraSource = new CameraSource.Builder(this, barcodeDetector)
                .setRequestedPreviewSize(1920, 1080)
                .setAutoFocusEnabled(true) //you should add this feature
                .build();

        surfaceView.getHolder().addCallback(new SurfaceHolder.Callback() {
            @Override
            public void surfaceCreated(SurfaceHolder holder) {
                try {
                    if (ActivityCompat.checkSelfPermission(BarcodeReaderActivity.this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {
                        cameraSource.start(surfaceView.getHolder());
                    } else {
                        ActivityCompat.requestPermissions(BarcodeReaderActivity.this, new
                                String[]{Manifest.permission.CAMERA}, REQUEST_CAMERA_PERMISSION);
                    }

                } catch (IOException e) {
                    e.printStackTrace();
                }

            }

            @Override
            public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

            }

            @Override
            public void surfaceDestroyed(SurfaceHolder holder) {
                cameraSource.stop();
            }
        });


        barcodeDetector.setProcessor(new Detector.Processor<Barcode>() {
            @Override
            public void release() {
                  Toast.makeText(getApplicationContext(), "To prevent memory leaks barcode scanner has been stopped", Toast.LENGTH_SHORT).show();
            }

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

                final SparseArray<Barcode> barcodes = detections.getDetectedItems();
                if (barcodes.size() != 0) {
                    Intent data = new Intent();
                    data.putExtra("FirstValue", barcodes.valueAt(0).displayValue);
                    setResult(RESULT_OK, data);
                    finish();

                }
            }
        });
    }


    @Override
    protected void onPause() {
        super.onPause();
        cameraSource.release();
    }

    @Override
    protected void onResume() {
        super.onResume();
        initialiseDetectorsAndSources();
    }

Answer 2

Yes u can go with google vision library for barcode scanning in your app. Checkout here