Rotate/flip images in Xamarin

GemBox.Imaging is a standalone .NET component with cross-platform support. You can use it on non-Windows platforms like Xamarin and Mono, enabling you to run it on Android and iOS mobile devices.

With GemBox.Imaging you can process your images (read, write, convert, and edit image files) from native mobile apps.

The following example shows how you can load, edit, and save files in a Xamarin.Forms mobile application.

Image rotator/flipper on a native Android mobile app with Xamarin.Forms — Screenshot of Xamarin Android app that rotates/flips image

XAML
C#

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<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="http://xamarin.com/schemas/2014/forms/design"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             mc:Ignorable="d"
             x:Class="ImagingXamarin.MainPage">

    <StackLayout Padding="30" 
                 Spacing="20">

        <Label Text="GemBox.Imaging Example"
               HorizontalOptions="Center"
               FontSize="Large" />

        <Picker x:Name="rotateFlipPicker" Title="Rotation/Flipping" ItemsSource="{Binding RotateFlipOptions}" ItemDisplayBinding="{Binding Text}" />

        <Image x:Name="sourceImage" Source="" HeightRequest="160" WidthRequest="160" />

        <Button x:Name="button"
                Text="TRANSFORM IMAGE"
                Clicked="Button_Clicked"/>

    </StackLayout>
</ContentPage>

using GemBox.Imaging;
using ImagingXamarin.Models;
using System;
using System.IO;
using System.Net;
using Xamarin.Essentials;
using Xamarin.Forms;

public partial class MainPage : ContentPage
{
    private byte[] imageData;

    public MainPage()
    {
        ComponentInfo.SetLicense("FREE-LIMITED-KEY");
        InitializeComponent();

        BindingContext = new RotateFlipViewModel();
    }

    protected override void OnAppearing()
    {
        base.OnAppearing();

        if (imageData == null)
            using (var client = new WebClient())
                this.imageData = client.DownloadData("https://www.gemboxsoftware.com/imaging/examples/101/resources/FragonardReader.jpg");

        this.sourceImage.Source = ImageSource.FromStream(() => new MemoryStream(this.imageData));
    }

    private string RotateImage(Stream stream)
    {
        var documentPath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
        var selectedRotationFlipping = (RotateFlipOption)rotateFlipPicker.SelectedItem;
        var destinationFilePath = Path.Combine(documentPath, $"{selectedRotationFlipping.Text}.jpg");
        using (var image = GemBox.Imaging.Image.Load(stream))
        {
            image.RotateFlip(selectedRotationFlipping.Type);
            image.Save(destinationFilePath);
        }
        return destinationFilePath;
    }

    private async void Button_Clicked(object sender, EventArgs e)
    {
        button.IsEnabled = false;

        try
        {
            var filePath = RotateImage(new MemoryStream(this.imageData));
            await Launcher.OpenAsync(new OpenFileRequest(Path.GetFileName(filePath), new ReadOnlyFile(filePath)));
        }
        catch (Exception ex)
        {
            await DisplayAlert("Error", ex.Message, "Close");
        }

        button.IsEnabled = true;
    }

    public class RotateFlipOption
    {
        public RotateFlipType Type { get; set; }
        public string Text { get; set; }
    }

    public class RotateFlipViewModel
    {
        public ICollection<RotateFlipOption> RotateFlipOptions { get; set; }

        public RotateFlipViewModel()
        {
            // Filling the collection for picker with possible RotateFlipTypes.
            this.RotateFlipOptions = Enum.GetNames(typeof(RotateFlipType))
                .Select(x => new RotateFlipOption
                {
                    Text = x,
                    Type = (RotateFlipType)Enum.Parse(typeof(RotateFlipType), x)
                }).ToList();
        }
    }
}

Next steps

GemBox.Imaging is a .NET component that provides an easy way to load, edit, save images. GemBox.Imaging also supports file format conversions and image transformations (resize, crop, rotate and flip).

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Published: September 21, 2022 | Modified: November 17, 2022 | Author: Ercan Görgülü

Rotate/flip images in Xamarin

See also

Next steps