How to scan QR Code Android (Beginner Tutorial)

QR codes are everywhere these days, serving as quick links to websites, discounts, or important information. However, the method to scan them isn't always the same across all Android devices. Depending on your phone model, you might be able to use your built-in camera app, or you might need a separate QR code scanner. To clear up any confusion, we've put together a detailed guide to help you scan QR codes effortlessly on any Android smartphone or tablet. We'll also explore a programmatic way to scan QR codes using the IronQR library.

Built-in Methods to Scan QR Codes on Android

Android devices often come equipped with native capabilities to support QR code scanning. These built-in methods offer convenience and security, as they don't require the installation of third-party applications. Let's examine the primary built-in options available to Android device users.

1. Google Lens App

Google Lens is a powerful visual analysis tool that includes QR code scanning capabilities. This application is often pre-installed on Android devices and can be accessed through various entry points.

Accessing Google Lens

Users can access Google Lens on their Android phone through several methods, depending on their device and preferences. The most common approach is via the Google App. Here are the steps to access Google Lens:

1. Open the Google App.
2. Locate the Google Lens icon near the search bar.

3. Tap the icon to activate Google Lens.

For those who prefer working with existing images, Google Photos offers another entry point. The process is as follows:

1. Open Google Photos.

2. Select an image containing a QR code.

3. Tap the Google Lens icon at the bottom of the screen. After that, you can use the Google Lens feature for QR code scanning.

Some Android devices, particularly those running more recent versions of the operating system, integrate Google Lens directly into the native camera application. Users of these devices can access Google Lens by:

1. Launching the camera app.
2. Looking for a "Modes" or "More" option.
3. Selecting Google Lens if available.

Using Google Lens for QR Code Scanning

Once Google Lens is activated, the process of scanning a QR code is straightforward. Here's how to use it:

1. Direct your device's camera towards the QR code.
2. Wait for Google Lens to automatically initiate a scan.
3. When a QR code is recognized, a pop-up will appear with the encoded information.
4. Tap the pop-up to proceed to the linked content or perform the associated action.

2. Quick Settings Tile

Some Android devices provide a Quick Settings tile for QR code scanning, offering rapid access to this functionality. To set up and use this feature:

1. Access the Quick Settings panel by swiping down from the top of the screen.

2. Expand the full panel with a second downward swipe.

3. Locate the edit function, often represented by a pencil icon or three-dot icons.

4. In edit mode, search for a tile labeled "QR code" or "QR Scanner."

5. Drag this tile into the active Quick Settings area.
6. Save the changes to confirm the new layout.

To utilize the Quick Settings QR code scanner:

1. Open the Quick Settings panel.
2. Tap the QR code scanner tile.
3. The device will launch a QR code scanning interface, which may utilize the camera app or Google Lens.
4. Point the camera at the QR code to initiate the scan.

These built-in methods offer Android users efficient ways to scan QR codes without the need for additional software installation. Users can quickly access the information encoded in QR codes while maintaining the security and integrity of their devices. Other than this, you can download a third-party app for QR code scanning on Android phones using the Google Play Store.

Introducing the IronQR .NET Library

While the built-in methods we've discussed provide excellent QR code scanning capabilities for end-users, developers often require more robust tools for creating and manipulating QR codes within their applications. This is where the IronQR .NET library comes into play. It offers a powerful solution for QR code functionality in Android app development.

Overview of IronQR

IronQR is a comprehensive .NET library designed for generating, reading QR codes, and manipulating QR codes. Although primarily targeted at .NET developers, it can be utilized in Android development through frameworks like Xamarin or .NET MAUI. It is a perfect choice for cross-platform applications with QR functionalities.

Key Features and Benefits

IronQR offers many features regarding QR code functionality:

1. QR Code Generation: Developers can create QR codes programmatically, controlling various parameters such as size, error correction level, and content.
2. Advanced Scanning Capabilities: The library provides robust algorithms for reading QR codes, even in challenging conditions or from images.
3. Customization Options: IronQR allows for the creation of customized QR codes, including the addition of logos or custom colors, while maintaining scannability.
4. Support for Various Data Types: The library can encode different types of data, including URLs, contact information, and custom text, into QR codes.
5. Error Handling and Correction: IronQR implements advanced error correction techniques, ensuring that generated QR codes are reliable and easily scannable.

Integration with Android Development

For Android developers working in a .NET environment, IronQR can be integrated into projects to provide server-side QR code generation or to enhance the capabilities of Android applications. This integration allows for more complex QR code operations that may not be possible with standard Android libraries.

Developers can create Android applications with sophisticated QR code functionalities, such as batch QR code generation, advanced decoding features, or custom QR code designs that align with branding requirements. The IronQR .NET library serves as a powerful tool for developers looking to extend the QR code capabilities of their Android applications beyond the standard built-in features.

Code Example

Here is a demonstration of a .NET MAUI QR Code Scanner App using IronQR. After installing the IronQR library in the project, update the MauiPage.xaml code:

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="QR_Code_Business_Card.MainPage"
             Title="QR Code Reader">
    <Grid Padding="20" RowDefinitions="Auto,*" ColumnDefinitions="*,Auto,*">
        <!-- Left side -->
        <VerticalStackLayout Grid.Row="1" Grid.Column="0" Spacing="20">
            <Button x:Name="ScanQRButton" 
                    Text="Scan QR Code"
                    Clicked="OnScanQRButtonClicked"
                    HorizontalOptions="Fill"
                    BackgroundColor="#6200EE"
                    TextColor="White"
                    FontAttributes="Bold"
                    CornerRadius="10" />
            <Frame BorderColor="#E0E0E0" Padding="0" CornerRadius="10" HasShadow="True">
                <Grid>
                    <Image x:Name="SelectedImage"
                           HeightRequest="300"
                           WidthRequest="300"
                           Aspect="AspectFit" />
                    <ActivityIndicator x:Name="LoadingIndicator"
                                       IsRunning="False"
                                       IsVisible="False"
                                       Color="#6200EE"
                                       VerticalOptions="Center"
                                       HorizontalOptions="Center" />
                </Grid>
            </Frame>
        </VerticalStackLayout>
        <!-- Divider -->
        <BoxView Grid.Row="0" Grid.RowSpan="2" Grid.Column="1" 
                 WidthRequest="1" 
                 Color="#E0E0E0" 
                 Margin="10,0" />
        <!-- Right side -->
        <VerticalStackLayout Grid.Row="1" Grid.Column="2" Spacing="20">
            <Frame BorderColor="#E0E0E0" Padding="10" CornerRadius="10" HasShadow="True">
                <Editor x:Name="ResultEditor"
                        HeightRequest="200"
                        IsReadOnly="True"
                        Placeholder="QR code content will appear here"
                        FontSize="16" />
            </Frame>
            <Button x:Name="CopyTextButton" 
                    Text="Copy Text"
                    Clicked="OnCopyTextButtonClicked"
                    HorizontalOptions="Fill"
                    BackgroundColor="#6200EE"
                    TextColor="White"
                    FontAttributes="Bold"
                    CornerRadius="10" />
        </VerticalStackLayout>
    </Grid>
</ContentPage>

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="QR_Code_Business_Card.MainPage"
             Title="QR Code Reader">
    <Grid Padding="20" RowDefinitions="Auto,*" ColumnDefinitions="*,Auto,*">
        <!-- Left side -->
        <VerticalStackLayout Grid.Row="1" Grid.Column="0" Spacing="20">
            <Button x:Name="ScanQRButton" 
                    Text="Scan QR Code"
                    Clicked="OnScanQRButtonClicked"
                    HorizontalOptions="Fill"
                    BackgroundColor="#6200EE"
                    TextColor="White"
                    FontAttributes="Bold"
                    CornerRadius="10" />
            <Frame BorderColor="#E0E0E0" Padding="0" CornerRadius="10" HasShadow="True">
                <Grid>
                    <Image x:Name="SelectedImage"
                           HeightRequest="300"
                           WidthRequest="300"
                           Aspect="AspectFit" />
                    <ActivityIndicator x:Name="LoadingIndicator"
                                       IsRunning="False"
                                       IsVisible="False"
                                       Color="#6200EE"
                                       VerticalOptions="Center"
                                       HorizontalOptions="Center" />
                </Grid>
            </Frame>
        </VerticalStackLayout>
        <!-- Divider -->
        <BoxView Grid.Row="0" Grid.RowSpan="2" Grid.Column="1" 
                 WidthRequest="1" 
                 Color="#E0E0E0" 
                 Margin="10,0" />
        <!-- Right side -->
        <VerticalStackLayout Grid.Row="1" Grid.Column="2" Spacing="20">
            <Frame BorderColor="#E0E0E0" Padding="10" CornerRadius="10" HasShadow="True">
                <Editor x:Name="ResultEditor"
                        HeightRequest="200"
                        IsReadOnly="True"
                        Placeholder="QR code content will appear here"
                        FontSize="16" />
            </Frame>
            <Button x:Name="CopyTextButton" 
                    Text="Copy Text"
                    Clicked="OnCopyTextButtonClicked"
                    HorizontalOptions="Fill"
                    BackgroundColor="#6200EE"
                    TextColor="White"
                    FontAttributes="Bold"
                    CornerRadius="10" />
        </VerticalStackLayout>
    </Grid>
</ContentPage>

After that, update the MauiPage.xaml.cs code:

using IronQr;
using IronSoftware.Drawing;
namespace QR_Code_Business_Card
{
    public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();
            License.LicenseKey = "License-Key";
        }

        private async void OnScanQRButtonClicked(object sender, EventArgs e)
        {
            try
            {
                var result = await FilePicker.PickAsync(new PickOptions
                {
                    FileTypes = FilePickerFileType.Images,
                    PickerTitle = "Pick an image with a QR code"
                });

                if (result != null)
                {
                    string filePath = result.FullPath;
                    SelectedImage.Source = ImageSource.FromFile(filePath);

                    // Show loading indicator
                    LoadingIndicator.IsVisible = true;
                    LoadingIndicator.IsRunning = true;
                    ResultEditor.Text = "Processing QR code...";

                    // Process QR code in the background
                    await Task.Run(() =>
                    {
                        var inputBmp = AnyBitmap.FromFile(filePath);
                        QrImageInput imageInput = new QrImageInput(inputBmp);
                        QrReader reader = new QrReader();
                        IEnumerable<QrResult> results = reader.Read(imageInput);

                        MainThread.BeginInvokeOnMainThread(() =>
                        {
                            if (results.Any())
                            {
                                string scannedData = results.First().Value.ToString();
                                ResultEditor.Text = scannedData;
                            }
                            else
                            {
                                ResultEditor.Text = "No QR code found in the image.";
                            }

                            // Hide loading indicator
                            LoadingIndicator.IsVisible = false;
                            LoadingIndicator.IsRunning = false;
                        });
                    });
                }
            }
            catch (Exception ex)
            {
                ResultEditor.Text = $"An error occurred: {ex.Message}";
                LoadingIndicator.IsVisible = false;
                LoadingIndicator.IsRunning = false;
            }
        }

        private async void OnCopyTextButtonClicked(object sender, EventArgs e)
        {
            if (!string.IsNullOrWhiteSpace(ResultEditor.Text))
            {
                await Clipboard.SetTextAsync(ResultEditor.Text);
                await DisplayAlert("Success", "Text copied to clipboard", "OK");
            }
            else
            {
                await DisplayAlert("Error", "No text to copy", "OK");
            }
        }
    }
}

using IronQr;
using IronSoftware.Drawing;
namespace QR_Code_Business_Card
{
    public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();
            License.LicenseKey = "License-Key";
        }

        private async void OnScanQRButtonClicked(object sender, EventArgs e)
        {
            try
            {
                var result = await FilePicker.PickAsync(new PickOptions
                {
                    FileTypes = FilePickerFileType.Images,
                    PickerTitle = "Pick an image with a QR code"
                });

                if (result != null)
                {
                    string filePath = result.FullPath;
                    SelectedImage.Source = ImageSource.FromFile(filePath);

                    // Show loading indicator
                    LoadingIndicator.IsVisible = true;
                    LoadingIndicator.IsRunning = true;
                    ResultEditor.Text = "Processing QR code...";

                    // Process QR code in the background
                    await Task.Run(() =>
                    {
                        var inputBmp = AnyBitmap.FromFile(filePath);
                        QrImageInput imageInput = new QrImageInput(inputBmp);
                        QrReader reader = new QrReader();
                        IEnumerable<QrResult> results = reader.Read(imageInput);

                        MainThread.BeginInvokeOnMainThread(() =>
                        {
                            if (results.Any())
                            {
                                string scannedData = results.First().Value.ToString();
                                ResultEditor.Text = scannedData;
                            }
                            else
                            {
                                ResultEditor.Text = "No QR code found in the image.";
                            }

                            // Hide loading indicator
                            LoadingIndicator.IsVisible = false;
                            LoadingIndicator.IsRunning = false;
                        });
                    });
                }
            }
            catch (Exception ex)
            {
                ResultEditor.Text = $"An error occurred: {ex.Message}";
                LoadingIndicator.IsVisible = false;
                LoadingIndicator.IsRunning = false;
            }
        }

        private async void OnCopyTextButtonClicked(object sender, EventArgs e)
        {
            if (!string.IsNullOrWhiteSpace(ResultEditor.Text))
            {
                await Clipboard.SetTextAsync(ResultEditor.Text);
                await DisplayAlert("Success", "Text copied to clipboard", "OK");
            }
            else
            {
                await DisplayAlert("Error", "No text to copy", "OK");
            }
        }
    }
}

Imports IronQr
Imports IronSoftware.Drawing
Namespace QR_Code_Business_Card
	Partial Public Class MainPage
		Inherits ContentPage

		Public Sub New()
			InitializeComponent()
			License.LicenseKey = "License-Key"
		End Sub

		Private Async Sub OnScanQRButtonClicked(ByVal sender As Object, ByVal e As EventArgs)
			Try
				Dim result = Await FilePicker.PickAsync(New PickOptions With {
					.FileTypes = FilePickerFileType.Images,
					.PickerTitle = "Pick an image with a QR code"
				})

				If result IsNot Nothing Then
					Dim filePath As String = result.FullPath
					SelectedImage.Source = ImageSource.FromFile(filePath)

					' Show loading indicator
					LoadingIndicator.IsVisible = True
					LoadingIndicator.IsRunning = True
					ResultEditor.Text = "Processing QR code..."

					' Process QR code in the background
					Await Task.Run(Sub()
						Dim inputBmp = AnyBitmap.FromFile(filePath)
						Dim imageInput As New QrImageInput(inputBmp)
						Dim reader As New QrReader()
						Dim results As IEnumerable(Of QrResult) = reader.Read(imageInput)

						MainThread.BeginInvokeOnMainThread(Sub()
							If results.Any() Then
								Dim scannedData As String = results.First().Value.ToString()
								ResultEditor.Text = scannedData
							Else
								ResultEditor.Text = "No QR code found in the image."
							End If

							' Hide loading indicator
							LoadingIndicator.IsVisible = False
							LoadingIndicator.IsRunning = False
						End Sub)
					End Sub)
				End If
			Catch ex As Exception
				ResultEditor.Text = $"An error occurred: {ex.Message}"
				LoadingIndicator.IsVisible = False
				LoadingIndicator.IsRunning = False
			End Try
		End Sub

		Private Async Sub OnCopyTextButtonClicked(ByVal sender As Object, ByVal e As EventArgs)
			If Not String.IsNullOrWhiteSpace(ResultEditor.Text) Then
				Await Clipboard.SetTextAsync(ResultEditor.Text)
				Await DisplayAlert("Success", "Text copied to clipboard", "OK")
			Else
				Await DisplayAlert("Error", "No text to copy", "OK")
			End If
		End Sub
	End Class
End Namespace

After running the application, you'll see the following UI. After selecting the QR code, it'll scan the QR code and show the result text in the text box, which you can copy using the copy button.

Conclusion

Scanning QR codes on Android devices is made easy with built-in features like Google Lens and Quick Settings tiles. These native methods provide users with quick and secure access to QR code information without the need for additional apps.

For developers aiming to incorporate advanced QR code functionalities into their applications, the IronQR .NET library offers a powerful solution. It enables custom QR code generation, advanced scanning capabilities, and extensive customization options. IronQR offers a free trial for developers to explore its features, with licenses starting from $749, making it a worthwhile investment for professional-grade QR code integration in Android applications.