Nowadays Barcodes and QR Codes are widely used in lot of mobile apps. In a QR Code you can store information like text, sms, email, url, image, audio and few other formats. In Android you can extract the information stored in barcodes by using Google Vision Library. Even though there are lot of other libraries available, google vision library is best to consider as it’s not only provide barcode reading but also have other features like face detection, text detection.

In this article we are going to learn how to use the google vision library by creating a simple movie ticket scanning app.

1. Google Mobile Vision API

Google Mobile Vision api helps in finding objects in an image or video. It provides functionalities like face detection, text detection and barcode detection. All these functionalities can be used separately or combined together.

This article aims to explain the barcode detection with a realtime use case scenario. We can see lot of barcode scanning apps used in supermarkets, theatres and hotels which scans a barcode and provides user desired information. In this article we’ll try to build a simple movie ticket scanner app which scans a barcode / qrcode and displays the movie information to book a ticket.

The google vision library is a part of play services and can be added to your project’s build.gradle.

compile 'com.google.android.gms:play-services-vision:11.0.2'

2. Barcode Scanner Library

Google provided a simple tutorial to tryout the barcode scanning library with a simple bitmap image. But when it comes to scanning a realtime camera feed for a barcode, things become difficult to implement as we need to perform barcode detection on camera video.

I have developed a simple barcode scanner library by forking the google vision sample. In this library few bugs were fixed and added other functionalities like callbacks when barcode is scanned and a overlay scanning line indicator that can be used in your apps.

3. How to Use the Barcode library

Follow the below simple steps to include the barcode / qrcode library in your project.

1. Add the androidhive barcode reader and google vision library to your app’s build.gradle file.

This article was written using Android Studio 3.0 Canary 9. The command compile is deprecated and replaced with implementation

dependencies { // barcode reader library implementation 'info.androidhive:barcode-reader:1.1.5' // google vision library implementation 'com.google.android.gms:play-services-vision:11.0.2' }

2. Add the barcode camera fragment to your activity or fragment.

<fragment android:id="@+id/barcode_scanner" android:name="info.androidhive.barcode.BarcodeReader" android:layout_width="match_parent" android:layout_height="match_parent" app:auto_focus="true" app:use_flash="false" />

3. Implement your Activity from BarcodeReader.BarcodeReaderListener and override the necessary methods.

import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.SparseArray; import com.google.android.gms.vision.barcode.Barcode; import java.util.List; import info.androidhive.barcode.BarcodeReader; public class MainActivity extends AppCompatActivity implements BarcodeReader.BarcodeReaderListener { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_scan); } @Override public void onScanned(Barcode barcode) { // single barcode scanned } @Override public void onScannedMultiple(List<Barcode> list) { // multiple barcodes scanned } @Override public void onBitmapScanned(SparseArray<Barcode> sparseArray) { // barcode scanned from bitmap image } @Override public void onScanError(String s) { // scan error } @Override public void onCameraPermissionDenied() { // camera permission denied } }

4. Run your project and try to scan barcode or qrcode. The scanned result will be returned in onScanned() or onScannedMultiple() method.

3.1 Adding Scanning Overlay Indicator Line

We can see all the scanning apps generally adds an indicator line on the camera overlay to indicate the scanning progress in going on. To achieve this, I have added a reusable class in the same library which can be added on to camera screen.

To add the animating scanning line, add the info.androidhive.barcode.ScannerOverlay to same activity overlapping the camera fragment.

<info.androidhive.barcode.ScannerOverlay android:layout_width="match_parent" android:layout_height="match_parent" android:background="#44000000" app:line_color="#7323DC" app:line_speed="6" app:line_width="4" app:square_height="200" app:square_width="200"/>

The library also contains few other useful functionalities like auto flash, beep sound etc., Detailed information about library can be found on it’s Github page.

4. Creating New Project – Building Simple Ticket Scanning App

As the barcode scanning library is already available, we’ll see how to use the library considering a real use case scenario. The app we are going to build not only explains the barcode scanning, but it also covers building the complex UI, making REST api calls to fetch the movie json and writing custom view classes.

Overall the app contains three screens. The first is splash screen, second is barcode scanning and the last one is to display the movie ticket information.

Below are the screenshots of the app.

4.1 The REST API

To build this app we need a REST api to search through movie database by movie barcode. I have written a simple rest api to search for a movie by barcode. This takes predefined barcode value as query param and searches it in the db. Here are the few sample barcodes for testing.

1. dn_barcode.jpg

2. spiderman_barcode.jpg

3. wonderwoman_barcode.jpg

4. dunkirk_barcode.jpg

Search Movie:

Make GET request with the barcode value read.

https://api.androidhive.info/barcodes/search.php?code=dunkirk

Movie Result:

The matched movie json will be given in the response.

{ "name": "Dunkirk", "poster": "https://api.androidhive.info/barcodes/dunkirk.jpg", "duration": "1hr 46min", "rating": 4.6, "released": true, "genre": "Action", "price": "₹200", "director": "Christopher Nolan" }

Now we have all the necessary information with us. Let’s start by creating a new project in Android Studio.

Note: This project is developed using Android Studio 3.0 Canary 9

1. Create a new project in Android Studio from File ⇒ New Project and fill the project details. I gave project name as MovieTickets and package name as info.androidhive.movietickets

2. Open app’s build.gradle and add the barcode and google vision dependencies. I am also adding Glide, Volley and Gson libraries as they are required to make http calls, json parsing and display images.

dependencies { implementation 'com.google.android.gms:play-services-vision:11.0.2' // vision barcode scanner implementation 'info.androidhive:barcode-reader:1.1.2' // glide image library implementation 'com.github.bumptech.glide:glide:4.0.0-RC1' annotationProcessor 'com.github.bumptech.glide:compiler:4.0.0-RC1' implementation 'com.android.volley:volley:1.0.0' implementation 'com.google.code.gson:gson:2.6.2' }

3. Add the below string, dimen, color resources to respective files under res directory.

<resources> <string name="app_name">Movie Tickets</string> <string name="title_activity_ticket">Book Ticket</string> <string name="lbl_duration">DURATION</string> <string name="lbl_genre">GENRE</string> <string name="lbl_rating">RATING</string> <string name="lbl_price">PRICE</string> <string name="btn_buy_now">BUY NOW</string> <string name="btn_coming_soon">COMING SOON</string> <string name="msg_no_ticket_found">No ticket found. Try scanning the QR Codes from http://api.androidhive.info/qrcodes/</string> </resources>

<?xml version="1.0" encoding="utf-8"?> <resources> <dimen name="dimen_20">20dp</dimen> <dimen name="dimen_10">10dp</dimen> <dimen name="activity_margin">16dp</dimen> <dimen name="lbl_directory">14dp</dimen> <dimen name="lbl_movie_name">28dp</dimen> <dimen name="img_poster_height">220dp</dimen> <dimen name="dimen_40">40dp</dimen> </resources>

<?xml version="1.0" encoding="utf-8"?> <resources> <color name="colorPrimary">#6d0094</color> <color name="colorPrimaryDark">#6d0094</color> <color name="colorAccent">#ff2068</color> <color name="colorAccentSecondary">#ad1a7f</color> <color name="viewBg">#f8f8f8</color> <color name="btn_disabled">#999</color> <color name="lbl_value">#222222</color> </resources>

4. Create a class named MyApplication.java and add the below code. Here we create volley singleton instance.

Volley is not suggested for making http calls, but to make the integration simple, it’s considered in this tutorial. Consider using Retrofit in your production apps.

import android.app.Application; import android.text.TextUtils; import com.android.volley.Request; import com.android.volley.RequestQueue; import com.android.volley.toolbox.Volley; /** * Created by ravi on 31/07/17. */ public class MyApplication extends Application { public static final String TAG = MyApplication.class .getSimpleName(); private RequestQueue mRequestQueue; private static MyApplication mInstance; @Override public void onCreate() { super.onCreate(); mInstance = this; } public static synchronized MyApplication getInstance() { return mInstance; } public RequestQueue getRequestQueue() { if (mRequestQueue == null) { mRequestQueue = Volley.newRequestQueue(getApplicationContext()); } return mRequestQueue; } public <T> void addToRequestQueue(Request<T> req, String tag) { // set the default tag if tag is empty req.setTag(TextUtils.isEmpty(tag) ? TAG : tag); getRequestQueue().add(req); } public <T> void addToRequestQueue(Request<T> req) { req.setTag(TAG); getRequestQueue().add(req); } public void cancelPendingRequests(Object tag) { if (mRequestQueue != null) { mRequestQueue.cancelAll(tag); } } }

5. Open AndroidManifest.xml and add the MyApplication class to <applicaton> tag. Also add the INTERNET permission as we need to make http calls.

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="info.androidhive.movietickets"> <uses-permission android:name="android.permission.INTERNET" /> <application android:name=".MyApplication" 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"> <activity android:name=".MainActivity" android:screenOrientation="portrait" android:theme="@style/AppTheme.NoActionBar"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".ScanActivity" android:screenOrientation="portrait" /> <activity android:name=".TicketActivity" android:label="@string/title_activity_ticket" android:screenOrientation="portrait" android:theme="@style/AppTheme.NoActionBar"></activity> </application> </manifest>

6. Under res ⇒ drawable folder create an xml drawable named bg_gradient.xml This drawable gives gradient background to view.

<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <gradient android:angle="135" android:centerColor="@color/colorAccentSecondary" android:endColor="@color/colorPrimary" android:startColor="@color/colorAccent" android:type="linear" /> <corners android:radius="0dp" /> </shape>

4.2 Adding Landing Screen

The landing screen will have few text fields and a button to open the scanner camera. The interesting thing you will learn here is giving gradient background to activity.

7. Open the layout file your main activity (activity_main.xml) add the below layout. Here we are adding button to launch scanner activity.

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout 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" android:background="@drawable/bg_gradient" tools:context="info.androidhive.movietickets.MainActivity"> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerHorizontal="true" android:layout_centerInParent="true" android:gravity="center" android:orientation="vertical" android:paddingLeft="40dp" android:paddingRight="40dp"> <ImageView android:id="@+id/icon" android:layout_width="100dp" android:layout_height="100dp" android:layout_centerHorizontal="true" android:clickable="true" android:foreground="?attr/selectableItemBackground" android:src="@drawable/qrcode" android:tint="@android:color/white" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="30dp" android:fontFamily="sans-serif-light" android:gravity="center" android:text="Scan the QR code on the poster and book your movie tickets" android:textColor="@android:color/white" android:textSize="16dp" /> </LinearLayout> <Button android:id="@+id/btn_scan" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true" android:layout_marginBottom="40dp" android:background="@android:color/transparent" android:foreground="?attr/selectableItemBackground" android:paddingLeft="20dp" android:paddingRight="20dp" android:fontFamily="sans-serif-medium" android:text="Scan QR Code" android:textColor="@android:color/white" android:textSize="18sp" /> </RelativeLayout>

8. Open the main activity and do the below necessary changes. In this activity transparentToolbar() method makes toolbar transparent. The button click listener launches the scanner activity which we are going to create shortly.

import android.app.Activity; import android.content.Intent; import android.graphics.Color; import android.os.Build; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.SparseArray; import android.view.View; import android.view.Window; import android.view.WindowManager; import com.google.android.gms.vision.barcode.Barcode; import java.util.List; import info.androidhive.barcode.BarcodeReader; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // making toolbar transparent transparentToolbar(); setContentView(R.layout.activity_main); findViewById(R.id.btn_scan).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { startActivity(new Intent(MainActivity.this, ScanActivity.class)); } }); } private void transparentToolbar() { if (Build.VERSION.SDK_INT >= 19 && Build.VERSION.SDK_INT < 21) { setWindowFlag(this, WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, true); } if (Build.VERSION.SDK_INT >= 19) { getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN); } if (Build.VERSION.SDK_INT >= 21) { setWindowFlag(this, WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS, false); getWindow().setStatusBarColor(Color.TRANSPARENT); } } private void setWindowFlag(Activity activity, final int bits, boolean on) { Window win = activity.getWindow(); WindowManager.LayoutParams winParams = win.getAttributes(); if (on) { winParams.flags |= bits; } else { winParams.flags &= ~bits; } win.setAttributes(winParams); } }

If you run the app, you can see the landing screen as below.

4.3 Adding Ticket Scan Screen

Now we have the landing screen ready. Let’s create the scanner activity.

9. Create a new activity from File ⇒ New ⇒ Activity ⇒ Empty Activity and name it as ScanActivity.java

10. Open layout file of ticket activity (activity_scan.xml) and add the Barcode Reader fragment as below. Here we are also adding the scanner line indicator animation view.

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout 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="info.androidhive.movietickets.ScanActivity"> <fragment android:id="@+id/barcode_scanner" android:name="info.androidhive.barcode.BarcodeReader" android:layout_width="match_parent" android:layout_height="match_parent" app:auto_focus="true" app:use_flash="false" /> <info.androidhive.barcode.ScannerOverlay android:layout_width="match_parent" android:layout_height="match_parent" android:background="#44000000" app:line_color="#7323DC" app:line_speed="6" app:line_width="4" app:square_height="200" app:square_width="200" /> </RelativeLayout>

11. Open ScanActivity.java and do the below necessary changes.

> Implement the activity from BarcodeReader.BarcodeReaderListener

> Override the callback methods onScanned(), onScannedMultiple() and other callbacks.

> barcodeReader.playBeep() plays beep sound upon barcode is read.

> Launch the TicketActivity once the barcode is scanned by passing the barcode value in intent.

package info.androidhive.movietickets; import android.content.Intent; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.SparseArray; import android.widget.Toast; import com.google.android.gms.vision.barcode.Barcode; import java.util.List; import info.androidhive.barcode.BarcodeReader; public class ScanActivity extends AppCompatActivity implements BarcodeReader.BarcodeReaderListener { BarcodeReader barcodeReader; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_scan); // get the barcode reader instance barcodeReader = (BarcodeReader) getSupportFragmentManager().findFragmentById(R.id.barcode_scanner); } @Override public void onScanned(Barcode barcode) { // playing barcode reader beep sound barcodeReader.playBeep(); // ticket details activity by passing barcode Intent intent = new Intent(ScanActivity.this, TicketActivity.class); intent.putExtra("code", barcode.displayValue); startActivity(intent); } @Override public void onScannedMultiple(List<Barcode> list) { } @Override public void onBitmapScanned(SparseArray<Barcode> sparseArray) { } @Override public void onCameraPermissionDenied() { finish(); } @Override public void onScanError(String s) { Toast.makeText(getApplicationContext(), "Error occurred while scanning " + s, Toast.LENGTH_SHORT).show(); } }

Run the app and try to scan any barcode. The scanned barcode will be returned in onScanned() method.

4.4 Adding Ticket Scan Result Screen

The next screen will be ticket results activity. On this screen the movie details will be displayed by sending the scanned qrcode to search endpoint and get the result.

If you observe the design, I have placed the movie details on a ticket view which will have punched holes in the corners. To achieve this I have created a custom view and made the holes using eraser.

4.4.1 Preparing Ticket View with Punching Holes

12. Create a class named TicketView.java. This is a plain view class in which the Canvas is used to render the view with transparent holes on the corners.

import android.content.Context; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.DashPathEffect; import android.graphics.Paint; import android.graphics.Path; import android.graphics.PorterDuff; import android.graphics.PorterDuffXfermode; import android.util.AttributeSet; import android.widget.LinearLayout; /** * Created by ravi tamada on 29/07/17. * Ticket view creates view with view punches making circular holes * in the view */ public class TicketView extends LinearLayout { private Bitmap bm; private Canvas cv; private Paint eraser; private int holesBottomMargin = 70; private int holeRadius = 40; public TicketView(Context context) { super(context); Init(); } public TicketView(Context context, AttributeSet attrs) { super(context, attrs); Init(); } public TicketView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); Init(); } private void Init() { eraser = new Paint(); eraser.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR)); eraser.setAntiAlias(true); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { if (w != oldw || h != oldh) { bm = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888); cv = new Canvas(bm); } super.onSizeChanged(w, h, oldw, oldh); } @Override protected void onDraw(Canvas canvas) { int w = getWidth(); int h = getHeight(); bm.eraseColor(Color.TRANSPARENT); // set the view background color cv.drawColor(Color.WHITE); // drawing footer square contains the buy now button Paint paint = new Paint(); paint.setARGB(255, 250, 250, 250); paint.setStrokeWidth(0); paint.setStyle(Paint.Style.FILL); cv.drawRect(0, h, w, h - pxFromDp(getContext(), holesBottomMargin), paint); // adding punching holes on the ticket by erasing them cv.drawCircle(0, 0, holeRadius, eraser); // top-left hole cv.drawCircle(w / 2, 0, holeRadius, eraser); // top-middle hole cv.drawCircle(w, 0, holeRadius, eraser); // top-right cv.drawCircle(0, h - pxFromDp(getContext(), holesBottomMargin), holeRadius, eraser); // bottom-left hole cv.drawCircle(w, h - pxFromDp(getContext(), holesBottomMargin), holeRadius, eraser); // bottom right hole // drawing the image canvas.drawBitmap(bm, 0, 0, null); // drawing dashed lines at the bottom Path mPath = new Path(); mPath.moveTo(holeRadius, h - pxFromDp(getContext(), holesBottomMargin)); mPath.quadTo(w - holeRadius, h - pxFromDp(getContext(), holesBottomMargin), w - holeRadius, h - pxFromDp(getContext(), holesBottomMargin)); // dashed line Paint dashed = new Paint(); dashed.setARGB(255, 200, 200, 200); dashed.setStyle(Paint.Style.STROKE); dashed.setStrokeWidth(2); dashed.setPathEffect(new DashPathEffect(new float[]{10, 5}, 0)); canvas.drawPath(mPath, dashed); super.onDraw(canvas); } public static float pxFromDp(final Context context, final float dp) { return dp * context.getResources().getDisplayMetrics().density; } }

13. Create new class named TicketResultActivity.java by navigating to File ⇒ New ⇒ Activity ⇒ Empty Activity.

14. Open the layout of ticket result activity (activity_ticket_result.xml) and add the below layout.

<?xml version="1.0" encoding="utf-8"?> <android.support.design.widget.CoordinatorLayout 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:id="@+id/main_content" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/bg_gradient" android:descendantFocusability="beforeDescendants" android:fitsSystemWindows="true" tools:context=".TicketResultActivity"> <android.support.design.widget.AppBarLayout foreground="?android:windowContentOverlay" android:layout_width="match_parent" android:layout_height="wrap_content" android:theme="@style/AppTheme.AppBarOverlay"> <android.support.v7.widget.Toolbar android:id="@+id/toolbar" android:layout_width="match_parent" android:layout_height="?actionBarSize" android:background="@color/colorPrimary" app:popupTheme="@style/AppTheme.PopupOverlay"></android.support.v7.widget.Toolbar> </android.support.design.widget.AppBarLayout> <include layout="@layout/content_ticket_details"/> </android.support.design.widget.CoordinatorLayout>

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout 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" android:background="@drawable/bg_gradient" app:layout_behavior="@string/appbar_scrolling_view_behavior" tools:context=".TicketResultActivity"> <TextView android:id="@+id/txt_error" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerHorizontal="true" android:layout_centerInParent="true" android:gravity="center_horizontal" android:text="@string/msg_no_ticket_found" android:textColor="@android:color/white" android:padding="@dimen/dimen_20" android:textSize="16dp" android:visibility="gone" /> <info.androidhive.movietickets.TicketView android:id="@+id/layout_ticket" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_marginLeft="@dimen/dimen_20" android:layout_marginRight="@dimen/dimen_20" android:layout_marginTop="@dimen/dimen_20" android:background="@android:color/transparent" android:orientation="vertical" android:paddingTop="@dimen/dimen_10" android:visibility="gone"> <TextView android:id="@+id/director" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:fontFamily="sans-serif-condensed" android:paddingLeft="@dimen/activity_margin" android:paddingRight="@dimen/activity_margin" android:paddingTop="@dimen/activity_margin" android:textAllCaps="true" android:textSize="@dimen/lbl_directory" /> <TextView android:id="@+id/name" android:layout_width="match_parent" android:layout_height="wrap_content" android:fontFamily="sans-serif-condensed" android:paddingLeft="16dp" android:paddingRight="16dp" android:textAllCaps="true" android:textColor="#111" android:maxLines="1" android:ellipsize="end" android:textSize="@dimen/lbl_movie_name" /> <ImageView android:id="@+id/poster" android:layout_width="match_parent" android:layout_height="@dimen/img_poster_height" android:layout_marginBottom="@dimen/activity_margin" android:layout_marginTop="@dimen/activity_margin" android:scaleType="centerCrop" /> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:paddingLeft="@dimen/activity_margin" android:paddingRight="@dimen/activity_margin" android:weightSum="2"> <LinearLayout android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:orientation="vertical"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:fontFamily="sans-serif-condensed" android:text="@string/lbl_duration" android:textSize="12dp" /> <TextView android:id="@+id/duration" android:layout_width="match_parent" android:layout_height="wrap_content" android:fontFamily="sans-serif-condensed" android:textColor="@color/lbl_value" android:textSize="22dp" /> </LinearLayout> <LinearLayout android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:orientation="vertical"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:fontFamily="sans-serif-condensed" android:text="@string/lbl_genre" android:textSize="12dp" /> <TextView android:id="@+id/genre" android:layout_width="match_parent" android:layout_height="wrap_content" android:fontFamily="sans-serif-condensed" android:textAllCaps="true" android:textColor="@color/lbl_value" android:textSize="22dp" /> </LinearLayout> </LinearLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="16dp" android:orientation="horizontal" android:paddingLeft="16dp" android:paddingRight="16dp" android:weightSum="2"> <LinearLayout android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:orientation="vertical"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:fontFamily="sans-serif-condensed" android:text="@string/lbl_rating" android:textSize="12dp" /> <TextView android:id="@+id/rating" android:layout_width="match_parent" android:layout_height="wrap_content" android:fontFamily="sans-serif-condensed" android:textColor="@color/lbl_value" android:textSize="22dp" /> </LinearLayout> <LinearLayout android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:orientation="vertical"> <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginBottom="5dp" android:fontFamily="sans-serif-condensed" android:text="@string/lbl_price" android:textSize="12dp" /> <TextView android:id="@+id/price" android:layout_width="match_parent" android:layout_height="wrap_content" android:fontFamily="sans-serif-condensed" android:textAllCaps="true" android:textColor="@color/lbl_value" android:textSize="22dp" /> </LinearLayout> </LinearLayout> </info.androidhive.movietickets.TicketView> <Button android:id="@+id/btn_buy" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true" android:layout_marginBottom="10dp" android:background="@android:color/transparent" android:fontFamily="sans-serif-condensed" android:foreground="?attr/selectableItemBackground" android:paddingLeft="@dimen/activity_margin" android:paddingRight="@dimen/activity_margin" android:textColor="@color/colorPrimary" android:textSize="26dp" /> <ProgressBar android:id="@+id/progressBar" android:layout_width="@dimen/dimen_40" android:layout_height="@dimen/dimen_40" android:layout_centerInParent="true" android:indeterminateTint="@android:color/white" android:indeterminateTintMode="src_atop" android:visibility="visible" /> </RelativeLayout>

15. Open the respective TicketResultActivity.java and modify the code as below.

> searchBarcode() makes the volley http call to search endpoint by passing the barcode scanned.

> renderMovie() parses the json and renders the movie details on the screen.

import android.os.Bundle; import android.support.v4.content.ContextCompat; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.Toolbar; import android.text.TextUtils; import android.util.Log; import android.view.MenuItem; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.ProgressBar; import android.widget.TextView; import android.widget.Toast; import com.android.volley.Request; import com.android.volley.Response; import com.android.volley.VolleyError; import com.android.volley.toolbox.JsonObjectRequest; import com.bumptech.glide.Glide; import com.google.gson.Gson; import com.google.gson.JsonSyntaxException; import com.google.gson.annotations.SerializedName; import org.json.JSONObject; public class TicketResultActivity extends AppCompatActivity { private static final String TAG = TicketResultActivity.class.getSimpleName(); // url to search barcode private static final String URL = "https://api.androidhive.info/barcodes/search.php?code="; private TextView txtName, txtDuration, txtDirector, txtGenre, txtRating, txtPrice, txtError; private ImageView imgPoster; private Button btnBuy; private ProgressBar progressBar; private TicketView ticketView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_ticket_result); Toolbar toolbar = findViewById(R.id.toolbar); setSupportActionBar(toolbar); getSupportActionBar().setDisplayHomeAsUpEnabled(true); txtName = findViewById(R.id.name); txtDirector = findViewById(R.id.director); txtDuration = findViewById(R.id.duration); txtPrice = findViewById(R.id.price); txtRating = findViewById(R.id.rating); imgPoster = findViewById(R.id.poster); txtGenre = findViewById(R.id.genre); btnBuy = findViewById(R.id.btn_buy); imgPoster = findViewById(R.id.poster); txtError = findViewById(R.id.txt_error); ticketView = findViewById(R.id.layout_ticket); progressBar = findViewById(R.id.progressBar); String barcode = getIntent().getStringExtra("code"); // close the activity in case of empty barcode if (TextUtils.isEmpty(barcode)) { Toast.makeText(getApplicationContext(), "Barcode is empty!", Toast.LENGTH_LONG).show(); finish(); } // search the barcode searchBarcode(barcode); } /** * Searches the barcode by making http call * Request was made using Volley network library but the library is * not suggested in production, consider using Retrofit */ private void searchBarcode(String barcode) { // making volley's json request JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.GET, URL + barcode, null, new Response.Listener<JSONObject>() { @Override public void onResponse(JSONObject response) { Log.e(TAG, "Ticket response: " + response.toString()); // check for success status if (!response.has("error")) { // received movie response renderMovie(response); } else { // no movie found showNoTicket(); } } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { Log.e(TAG, "Error: " + error.getMessage()); showNoTicket(); } }); MyApplication.getInstance().addToRequestQueue(jsonObjReq); } private void showNoTicket() { txtError.setVisibility(View.VISIBLE); ticketView.setVisibility(View.GONE); progressBar.setVisibility(View.GONE); } /** * Rendering movie details on the ticket */ private void renderMovie(JSONObject response) { try { // converting json to movie object Movie movie = new Gson().fromJson(response.toString(), Movie.class); if (movie != null) { txtName.setText(movie.getName()); txtDirector.setText(movie.getDirector()); txtDuration.setText(movie.getDuration()); txtGenre.setText(movie.getGenre()); txtRating.setText("" + movie.getRating()); txtPrice.setText(movie.getPrice()); Glide.with(this).load(movie.getPoster()).into(imgPoster); if (movie.isReleased()) { btnBuy.setText(getString(R.string.btn_buy_now)); btnBuy.setTextColor(ContextCompat.getColor(this, R.color.colorPrimary)); } else { btnBuy.setText(getString(R.string.btn_coming_soon)); btnBuy.setTextColor(ContextCompat.getColor(this, R.color.btn_disabled)); } ticketView.setVisibility(View.VISIBLE); progressBar.setVisibility(View.GONE); } else { // movie not found showNoTicket(); } } catch (JsonSyntaxException e) { Log.e(TAG, "JSON Exception: " + e.getMessage()); showNoTicket(); Toast.makeText(getApplicationContext(), "Error occurred. Check your LogCat for full report", Toast.LENGTH_SHORT).show(); } catch (Exception e) { // exception showNoTicket(); Toast.makeText(getApplicationContext(), "Error occurred. Check your LogCat for full report", Toast.LENGTH_SHORT).show(); } } @Override public boolean onOptionsItemSelected(MenuItem item) { if (item.getItemId() == android.R.id.home) { finish(); } return super.onOptionsItemSelected(item); } private class Movie { String name; String director; String poster; String duration; String genre; String price; float rating; @SerializedName("released") boolean isReleased; public String getName() { return name; } public String getDirector() { return director; } public String getPoster() { return poster; } public String getDuration() { return duration; } public String getGenre() { return genre; } public String getPrice() { return price; } public float getRating() { return rating; } public boolean isReleased() { return isReleased; } } }

Now if you run the app and scan the qr codes provided in this article, the results will be shown as below.

5. Testing the App

The app can scan any barcode but the movie ticket information will be shown only when the qr code is scanned provided in this article.

Run the app and try to scan the below qr codes. You should able to see the proper movie information as shown in the demo.

1. dn_barcode.jpg

2. spiderman_barcode.jpg

3. wonderwoman_barcode.jpg

4. dunkirk_barcode.jpg