QR And Bar Code Scanning in Android

Hello Guys,

Here I share a sample code for QR Code and Bar Code Scanning using Android App.

No need to install any third party app for scanning.

Just see the sample code.

Sample Code:

File: CaptureActivity.java

package com.sneha.quick_response_code;

import java.text.DateFormat;
import java.util.Date;
import java.util.EnumSet;
import java.util.Map;
import java.util.Set;
import com.sneha.quick_response_code.result.ResultHandler;
import com.sneha.quick_response_code.result.ResultHandlerFactory;
import com.google.zxing.Result;
import com.google.zxing.ResultMetadataType;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.util.Log;
import android.util.TypedValue;
import android.view.KeyEvent;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;


public class CaptureActivity extends DecoderActivity
{
    private static final String TAG = CaptureActivity.class.getSimpleName();
    private static final Set<ResultMetadataType> DISPLAYABLE_METADATA_TYPES =                     EnumSet.of(ResultMetadataType.ISSUE_NUMBER, ResultMetadataType.SUGGESTED_PRICE,
    ResultMetadataType.ERROR_CORRECTION_LEVEL,                                                                         ResultMetadataType.POSSIBLE_COUNTRY);

    private TextView statusView = null;
    private View resultView = null;
    private boolean inScanMode = false;

    @Override
    public void onCreate(Bundle icicle)
    {
        super.onCreate(icicle);
        setContentView(R.layout.capture);
        Log.v(TAG, "onCreate()");

        resultView = findViewById(R.id.result_view);
        statusView = (TextView) findViewById(R.id.status_view);

        inScanMode = false;
    }

    @Override
    protected void onDestroy()
    {
        super.onDestroy();
        Log.v(TAG, "onDestroy()");
    }

    @Override
    protected void onResume()
    {
        super.onResume();
        Log.v(TAG, "onResume()");
    }

    @Override
    protected void onPause()
    {
        super.onPause();
        Log.v(TAG, "onPause()");
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event)
    {
        if (keyCode == KeyEvent.KEYCODE_BACK)
        {
            if (inScanMode)
                finish();
            else
                onResume();
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

    @Override
    public void handleDecode(Result rawResult, Bitmap barcode)
    {
        drawResultPoints(barcode, rawResult);

        ResultHandler resultHandler = ResultHandlerFactory.makeResultHandler(this, rawResult);
        handleDecodeInternally(rawResult, resultHandler, barcode);
    }

    protected void showScanner()
    {
        inScanMode = true;
        resultView.setVisibility(View.GONE);
        statusView.setText(R.string.msg_default_status);
        statusView.setVisibility(View.VISIBLE);
        viewfinderView.setVisibility(View.VISIBLE);
    }

    protected void showResults()
    {
        inScanMode = false;
        statusView.setVisibility(View.GONE);
        viewfinderView.setVisibility(View.GONE);
        resultView.setVisibility(View.VISIBLE);
    }

    // Put up our own UI for how to handle the decodBarcodeFormated contents.
    private void handleDecodeInternally(Result rawResult, ResultHandler resultHandler, Bitmap barcode)
    {
        onPause();
        showResults();

        ImageView barcodeImageView = (ImageView) findViewById(R.id.barcode_image_view);
     
        if (barcode == null)
        {
            barcodeImageView.setImageBitmap(BitmapFactory.decodeResource(getResources(),                         R.drawable.icon));
        }
        else
        {
            barcodeImageView.setImageBitmap(barcode);
        }

        TextView formatTextView = (TextView) findViewById(R.id.format_text_view);
        formatTextView.setText(rawResult.getBarcodeFormat().toString());

        TextView typeTextView = (TextView) findViewById(R.id.type_text_view);
        typeTextView.setText(resultHandler.getType().toString());

        DateFormat formatter = DateFormat.getDateTimeInstance(DateFormat.SHORT,                                   DateFormat.SHORT);
        String formattedTime = formatter.format(new Date(rawResult.getTimestamp()));
        TextView timeTextView = (TextView) findViewById(R.id.time_text_view);
        timeTextView.setText(formattedTime);

        TextView metaTextView = (TextView) findViewById(R.id.meta_text_view);
        View metaTextViewLabel = findViewById(R.id.meta_text_view_label);
        metaTextView.setVisibility(View.GONE);
        metaTextViewLabel.setVisibility(View.GONE);
        Map<ResultMetadataType, Object> metadata = rawResult.getResultMetadata();
       
        if (metadata != null)
        {
            StringBuilder metadataText = new StringBuilder(20);
           
            for (Map.Entry<ResultMetadataType, Object> entry : metadata.entrySet())
            {
                if (DISPLAYABLE_METADATA_TYPES.contains(entry.getKey()))
                {
                    metadataText.append(entry.getValue()).append('\n');
                }
            }
           
            if (metadataText.length() > 0)
            {
                metadataText.setLength(metadataText.length() - 1);
                metaTextView.setText(metadataText);
                metaTextView.setVisibility(View.VISIBLE);
                metaTextViewLabel.setVisibility(View.VISIBLE);
            }
        }

        TextView contentsTextView = (TextView) findViewById(R.id.contents_text_view);
        CharSequence displayContents = resultHandler.getDisplayContents();
        contentsTextView.setText(displayContents);
        // Crudely scale betweeen 22 and 32 -- bigger font for shorter text
        int scaledSize = Math.max(22, 32 - displayContents.length() / 4);
        contentsTextView.setTextSize(TypedValue.COMPLEX_UNIT_SP, scaledSize);
    }
}

Output:

Download Full Source Code From Here: QRBarCodeScanner

Happy Coding...!!!