how to create qr code reader in android studio

In this article today learn how to create qr code reader in android studio so lets start tutorial.

What is barcode scanner:

Clients new to barcoding typically take, `` What is the barcode reader? '' The statement is simple: The barcode scanner—also called The barcode reader—is The electronic device that decodes and physically captures data contained at barcodes. It comprises of the following elements, which work together to gather the information contained in the printed barcode:

The barcode reader (or barcode reader) is the machine peripheral for reading barcodes published on different surfaces. The barcode reader consists of a detector, a decoder (either built-in or external) , and the wire used to connect the audience with the computer. Additionally, almost all barcode readers currently created contain decoder circuitry examining the barcode’s picture information offered by the image conductor and mailing the barcode’s message to the scanner’s output port. CCD readers: CCD (cost Coupled Device) readers (also referred to as LED reader) have the array of hundreds of small fluorescent detectors lined up in one line in the head of the reader. This significant difference between the CCD audience and the pen or laser reader is that this CCD audience is evaluating emitted ambient lighting from this room code whereas pen or laser scanners are measuring reflected light of a specific frequency originating from the scanner itself.

Follow the full source code how to create qr code reader in android studio:

1.build.gradle:

implementation 'com.google.android.gms:play-services-vision:11.8.0'

2.MainActivity.java:

package com.akash.barcodescanner;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

public class MainActivity extends AppCompatActivity {

Button btnScanBarcode;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btnScanBarcode = findViewById(R.id.btnScanBarcode);

btnScanBarcode.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View view) {

startActivity(new Intent(MainActivity.this, ScannedBarcodeActivity.class));

}

});

}

3.activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context=".MainActivity">

<Button

android:id="@+id/btnScanBarcode"

android:layout_width="300dp"

android:layout_height="wrap_content"

android:layout_centerHorizontal="true"

android:layout_marginBottom="44dp"

android:layout_marginEnd="8dp"

android:layout_marginStart="8dp"

android:text="@string/scan_barcode"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintHorizontal_bias="0.676"

app:layout_constraintStart_toStartOf="parent" />

</android.support.constraint.ConstraintLayout>

4.ScannedBarcodeActivity.java:

package com.akash.barcodescanner;

import android.Manifest;

import android.content.Intent;

import android.content.pm.PackageManager;

import android.net.Uri;

import android.os.Bundle;

import android.util.SparseArray;

import android.view.SurfaceHolder;

import android.view.SurfaceView;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import androidx.core.app.ActivityCompat;

import com.google.android.gms.vision.CameraSource;

import com.google.android.gms.vision.Detector;

import com.google.android.gms.vision.barcode.Barcode;

import com.google.android.gms.vision.barcode.BarcodeDetector;

import java.io.IOException;

public class ScannedBarcodeActivity 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;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_scanned_barcode);

initViews();

}

private void initViews() {

txtBarcodeValue = findViewById(R.id.txtBarcodeValue);

surfaceView = findViewById(R.id.surfaceView);

btnAction = findViewById(R.id.btnAction);

btnAction.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

if (intentData.length() > 0) {

if (isEmail)

startActivity(new Intent(ScannedBarcodeActivity.this, EmailActivity.class).putExtra("email_address", intentData));

else {

startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(intentData)));

}

});

}

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(ScannedBarcodeActivity.this, Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) {

cameraSource.start(surfaceView.getHolder());

} else {

ActivityCompat.requestPermissions(ScannedBarcodeActivity.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) {

txtBarcodeValue.post(new Runnable() {

@Override

public void run() {

if (barcodes.valueAt(0).email != null) {

txtBarcodeValue.removeCallbacks(null);

intentData = barcodes.valueAt(0).email.address;

txtBarcodeValue.setText(intentData);

isEmail = true;

btnAction.setText("ADD CONTENT TO THE MAIL");

} else {

isEmail = false;

btnAction.setText("LAUNCH URL");

intentData = barcodes.valueAt(0).displayValue;

txtBarcodeValue.setText(intentData);

}

});

}

});

}

@Override

protected void onPause() {

super.onPause();

cameraSource.release();

}

@Override

protected void onResume() {

super.onResume();

initialiseDetectorsAndSources();

}

5.activity_scanned_barcode.xml:

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:padding="@dimen/activity_horizontal_margin">

<SurfaceView

android:id="@+id/surfaceView"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:layout_above="@+id/btnAction"

android:layout_alignParentLeft="true"

android:layout_alignParentStart="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_marginLeft="@dimen/activity_horizontal_margin"

android:layout_marginStart="@dimen/activity_horizontal_margin"

android:text="No Barcode Detected"

android:textColor="@android:color/white"

android:textSize="20sp" />

<Button

android:id="@+id/btnAction"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_alignParentBottom="true"

android:text="ADD CONTENT IN THE MAIL" />

</RelativeLayout>

6.EmailActivity.java:

package com.akash.barcodescanner;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.TextView;

public class EmailActivity extends AppCompatActivity implements View.OnClickListener {

EditText inSubject, inBody;

TextView txtEmailAddress;

Button btnSendEmail;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_email);

initViews();

}

private void initViews() {

inSubject = findViewById(R.id.inSubject);

inBody = findViewById(R.id.inBody);

txtEmailAddress = findViewById(R.id.txtEmailAddress);

btnSendEmail = findViewById(R.id.btnSendEmail);

if (getIntent().getStringExtra("email_address") != null) {

txtEmailAddress.setText("Recipient : " + getIntent().getStringExtra("email_address"));

}

btnSendEmail.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

Intent intent = new Intent(Intent.ACTION_SEND);

intent.setType("text/plain");

intent.putExtra(Intent.EXTRA_EMAIL, new String[]{txtEmailAddress.getText().toString()});

intent.putExtra(Intent.EXTRA_SUBJECT, inSubject.getText().toString().trim());

intent.putExtra(Intent.EXTRA_TEXT, inBody.getText().toString().trim());

startActivity(Intent.createChooser(intent, "Send Email"));

}

});

}

@Override

public void onClick(View v) {

switch (v.getId()) {

case R.id.btnScanBarcode:

startActivity(new Intent(EmailActivity.this, ScannedBarcodeActivity.class));

break;

}

7.activity_email.xml:

<?xml version="1.0" encoding="utf-8"?>

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context=".EmailActivity">

<Button

android:id="@+id/btnSendEmail"

android:layout_width="300dp"

android:layout_height="wrap_content"

android:layout_below="@+id/inBody"

android:layout_centerHorizontal="true"

android:layout_marginBottom="64dp"

android:layout_marginEnd="8dp"

android:layout_marginStart="8dp"

android:text="@string/send_email"

app:layout_constraintBottom_toBottomOf="parent"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent" />

<TextView

android:id="@+id/txtEmailAddress"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_alignParentTop="true"

android:layout_marginBottom="8dp"

android:layout_marginEnd="8dp"

android:layout_marginStart="8dp"

android:layout_marginTop="8dp"

android:text="Email Address: "

android:textSize="16dp"

android:textStyle="bold"

app:layout_constraintBottom_toTopOf="@+id/inSubject"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent" />

<EditText

android:id="@+id/inSubject"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@+id/txtEmailAddress"

android:layout_centerHorizontal="true"

android:layout_marginEnd="8dp"

android:layout_marginStart="8dp"

android:layout_marginTop="88dp"

android:ems="10"

android:hint="Subject"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent" />

<EditText

android:id="@+id/inBody"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_below="@+id/inSubject"

android:layout_centerHorizontal="true"

android:layout_marginEnd="8dp"

android:layout_marginStart="8dp"

android:layout_marginTop="164dp"

android:ems="10"

android:hint="Body"

app:layout_constraintEnd_toEndOf="parent"

app:layout_constraintHorizontal_bias="1.0"

app:layout_constraintStart_toStartOf="parent"

app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

8.AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="com.akash.barcodescanner">

<uses-feature

android:name="android.hardware.camera"

android:required="true" />

<uses-permission android:name="android.permission.CAMERA" />

<uses-feature android:name="android.hardware.camera.autofocus" />

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<uses-permission android:name="android.permission.INTERNET" />

<application

android:allowBackup="true"

android:icon="@mipmap/ic_launcher"

android:label="@string/app_name"

android:roundIcon="@mipmap/ic_launcher_round"

android:supportsRtl="true"

android:theme="@style/AppTheme">

<intent-filter>

</intent-filter>

</activity>

</application>

</manifest>

9.strings.xml:

<string name="app_name">Barcode scanner</string>

<string name="scan_barcode">scan_barcode</string>

<string name="send_email">send_email</string>

</resources>

10.dimens.xml:

</resources>

Android Tutorial

Thursday 11 June 2020

how to create qr code reader in android studio