David Ortinau

Posted on Jul 5, 2022

Roundup of .NET MAUI - Week of June 27, 2022

#dotnet #beginners

What better way to catch up from my vacation than to check out the latest updates to .NET MAUI content via NuGets and YouTube videos? Ya'll been busy! Here we go:

NuGets

Source Generators

Are you looking for source generators to reduce the boilerplate code you need to write when creating bindable properties for custom components? Here are a few options:

Syncfusion Updates

Syncfusion has published update v20.2.36 for a bunch of .NET MAUI controls including:

SignaturePad
DataGrid
Maps
Barcode
Sliders
ListView
Scheduler
Gauges
Charts
TabView

https://www.syncfusion.com/maui-controls

MauiReactor + HotReload

MauiReactor is an MVU "Component based UI library inspired by ReactJS and Flutter", and the successor to ReactorUI which was based on Xamarin.Forms. Coupled with it's own Hot Reload component, and you have a nice, productive C# first development experience.

adospace / reactorui-maui

MauiReactor is a MVU UI framework built on top of .NET MAUI

MauiReactor

Component-based UI Library built on top of .NET MAUI

MauiReactor is .NET library written on top of .NET MAUI that allows you to write applications in pure C# using an MVU approach.

This is the classic Counter app in MauiReactor:

class CounterPageState
{
    public int Counter { get; set; }
}

class CounterPage : Component<CounterPageState>
{
    public override VisualNode Render()
        => ContentPage("Counter Sample",
            VStack(
                Label($"Counter: {State.Counter}"),

                Button("Click To Increment", () =>
                    SetState(s => s.Counter++))
            )
            .Spacing(10)
            .Center()
        );
    
}

Setting up MauiReactor from CLI

Install MauiReactor templates

dotnet new install Reactor.Maui.TemplatePack

Install MauiReactor hot reload console command

dotnet tool install -g Reactor.Maui.HotReload

If you already…

View on GitHub

using MauiReactor.WeatherTwentyOne.Pages.Components;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MauiReactor.WeatherTwentyOne.Pages
{
    internal class HomePage : Component
    {
        public override VisualNode Render()
        {
            return new ContentPage(title: "Redmond, WA")
            {
                Device.Idiom == TargetIdiom.Desktop ?
                RenderDesktopLayout()
                :
                RenderPhoneLayout()
            };
        }

        private VisualNode RenderPhoneLayout()
        {
            return new ScrollView
            {
                new VerticalStackLayout
                {
                    new CurrentWidget(),

                    new BoxView()
                        .HeightRequest(1),

                    new Next24HrWidget(),

                    new Next7DWidget()
                }
                .Padding(0,50)
                .Spacing(25)
            };
        }

        private VisualNode RenderDesktopLayout()
            => new Grid(
                rows: "*",
                columns: "*,500")
                {
                    new ScrollView
                    {
                        new VerticalStackLayout
                        {
                            new FlexLayout
                            {
                                new CurrentWidget()
                                    .Width(200),

                                new WindLiveWidget(),
                            }
                            .MinimumHeightRequest(360)
                            .AlignItems(Microsoft.Maui.Layouts.FlexAlignItems.Center)
                            .AlignContent(Microsoft.Maui.Layouts.FlexAlignContent.Center)
                            .JustifyContent(Microsoft.Maui.Layouts.FlexJustify.SpaceEvenly),

                            new BoxView()
                                .HeightRequest(1),

                            new Next24HrWidget(),

                            new Next7DWidget()
                        }
                        .Padding(0,50)
                        .Spacing(50)
                    },

                    new WidgetsPanel()
                        .GridColumn(1)
                };

    }
}

SkiaSharp.Views.Maui.Controls

This set of SkiaSharp views can be added to any .NET MAUI application for drawing. This is similar to what you can do with the built-in GraphicsView and Microsoft.Maui.Graphics, but directly to SkiaSharp.

<skia:SKCanvasView x:Name="skiaView" PaintSurface="OnPaintSurface"
                       EnableTouchEvents="True" Touch="OnTouch"
                       IgnorePixelScaling="True" />

private void OnPaintSurface(object sender, SKPaintSurfaceEventArgs e)
        {
            // the the canvas and properties
            var canvas = e.Surface.Canvas;

            // make sure the canvas is blank
            canvas.Clear(SKColors.White);

            // decide what the text looks like
            using var paint = new SKPaint
            {
                Color = SKColors.Black,
                IsAntialias = true,
                Style = SKPaintStyle.Fill,
                TextAlign = SKTextAlign.Center,
                TextSize = 24
            };

            // adjust the location based on the pointer
            var coord = (touchLocation is SKPoint loc)
                ? new SKPoint(loc.X, loc.Y)
                : new SKPoint(e.Info.Width / 2, (e.Info.Height + paint.TextSize) / 2);

            // draw some text
            canvas.DrawText("SkiaSharp", coord, paint);
        }

OnScreenSize XAML Markup Extension

Just like with OnPlatform and OnIdiom, you can specify different values to control properties based on screen dimensions with this library. This looks useful, so long as you agree on the predefined sizes I suppose. This doesn't look like it would be adaptive at runtime. For this I recommend using adaptive triggers and providing your own size requirements.

carolzbnbr / OnScreenSizeMarkup

OnScreenSizeMarkup is a XAML markup extension for controlling UI elements (Views) based on the category a device's screen sizes fits in (Medium-sized devices, Large-sized devices, and etc).

This project is based on a post I wrote a long time ago for my blog.

.NET MAUI library Moved to another Repository

The .NET MAUI library has been separated into its own repository. If you are looking for the library for .NET MAUI, please go here.

If you are looking for Xamarin library, keep on this current repo.

OnScreenSizeMarkup: A XAML markup extension

OnScreenSizeMarkup is XAML markup extension for controlliing UI elements depending on the device screen size category.

Where can I use it?

OnScreenSizeMarkup is currently compatible with:

Xamarin.Forms
MAUI

What does that mean?

It works exactly as other markup extensions such as OnPlatform or OnIdiom, allowing you to control UI views accordding to the screen sizes category a device fits in.

Screen Categories

The screen sizes are grouped into six categories:

ExtraSmall - Tiny devices as an Apple Watch.
Small - Small devices, such…

View on GitHub

<Grid RowDefinitions="{markups:OnScreenSize Large='200, *, 200', 
                                                     ExtraLarge='300, *, 300',
                                                     DefaultSize='100, *, 100'}">
            <Label 
                    Padding="{markups:OnScreenSize 
                            Medium='15, 15, 0, 0', 
                            Large='20, 20, 0, 0', 
                            DefaultSize='10, 10, 0, 0'}"
                    Text="Hello" TextColor="White" />
         </Grid>

ImageEdit

This is a fork of a Xamarin.Forms library updated to support .NET MAUI mobile platforms for image manipulation.

https://www.nuget.org/packages/Xamarin.Plugin.ImageEdit.NET/2.0.0-alpha1

using (var image = await CrossImageEdit.Current.CreateImageAsync(imageByteArray)) {
    var croped = await Task.Run(() =>
            image.Crop(10, 20, 250, 100)
                 .Rotate(180)
                 .Resize(100, 0)
                 .ToPng()
    );
}

TinyMVVM

There are many MVVM libraries out there, but perhaps none as "tiny".

https://www.nuget.org/packages/TinyMvvm.Maui/4.0.1-pre9

BLE.Net

Another library forked and updated to .NET 6 from Xamarin, this provides bluetooth functionality for mobile platforms.

https://www.nuget.org/packages/Plugin.BLE.Net/3.0.0-alpha.1

Videos

SignalR

Real-time messaging between your .NET MAUI app and a server/service.

[French] DevFest - .NET MAUI : Mais c'est quoi ce truc ?

Helicopter Game

A 60s video to inspire. Yes, you can create 2D graphics and games in .NET MAUI. :)

[Portugues] Windows Subsystem for Android

Why MVVM?

James Montemagno breaks down the what, why, and how of MVVM for .NET MAUI apps.

.NET MAUI Arduino(?)

Looks like a .NET MAUI app running on Windows and using an older DLL that works with some Arduino device. 대박!

youtube.com

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