.NET MAUI Blazor Hybrid Development

Expert guidance for building cross-platform apps with .NET MAUI and Blazor.

Implementation Workflow 1. Analysis Phase (Required)

Before implementation, determine:

App type: Pure MAUI Blazor or MAUI + Blazor Web App (shared UI) Platform targets: Android, iOS, Windows, macOS Native features needed: Sensors, camera, file system, notifications State management: Component state, MVVM, or hybrid approach Navigation pattern: Blazor-only, Shell, or mixed navigation 2. Architecture Decision Scenario Recommended Approach Mobile-first with some web maui-blazor template Shared UI across mobile + web maui-blazor-web template with RCL Complex native integration MVVM with platform services Simple data-driven UI Component state with DI services 3. Project Setup // MauiProgram.cs - Essential setup public static MauiApp CreateMauiApp() { var builder = MauiApp.CreateBuilder(); builder .UseMauiApp() .ConfigureFonts(fonts => { fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular"); });

builder.Services.AddMauiBlazorWebView();

if DEBUG

builder.Services.AddBlazorWebViewDeveloperTools();

endif

// Register services
builder.Services.AddSingleton<IDeviceService, DeviceService>();
builder.Services.AddScoped<IDataService, DataService>();

return builder.Build();

}

1. BlazorWebView Configuration

Core Patterns Dependency Injection Lifetime Use Case AddSingleton App-wide state, device services, settings AddScoped Per-BlazorWebView instance state AddTransient Stateless utilities, factories // Interface for platform-specific implementation public interface IDeviceService { string GetDeviceModel(); Task HasPermissionAsync(string permission); }

// Platform implementation registered in MauiProgram.cs builder.Services.AddSingleton();

Component Lifecycle @code { [Parameter] public string Id { get; set; } = "";

// Called once when component initializes
protected override async Task OnInitializedAsync()
{
    await LoadDataAsync();
}

// Called when parameters change (including first render)
protected override void OnParametersSet()
{
    // React to parameter changes
}

// Called after each render
protected override void OnAfterRender(bool firstRender)
{
    if (firstRender)
    {
        // JS interop safe here
    }
}

}

Platform Feature Access // Check platform and access native features @inject IDeviceService DeviceService

@if (DeviceInfo.Current.Platform == DevicePlatform.Android) { }

@code { private async Task AccessCameraAsync() { var status = await Permissions.CheckStatusAsync(); if (status != PermissionStatus.Granted) { status = await Permissions.RequestAsync(); }

    if (status == PermissionStatus.Granted)
    {
        // Use camera
    }
}

}

State Updates from External Events @implements IDisposable @inject IDataService DataService

@message

@code { private string message = "";

protected override void OnInitialized()
{
    DataService.OnDataChanged += HandleDataChanged;
}

private async void HandleDataChanged(object? sender, EventArgs e)
{
    message = "Data updated!";
    await InvokeAsync(StateHasChanged); // Required for external events
}

public void Dispose()
{
    DataService.OnDataChanged -= HandleDataChanged;
}

}

Reference Documentation

For detailed patterns and examples, see:

Project Structure: Solution templates, RCL setup, multi-targeting Blazor Components: Lifecycle, RenderFragment, EventCallback, data binding Platform Integration: Device APIs, permissions, platform-specific code Navigation & Routing: Blazor routing, Shell, deep linking State Management: MVVM, DI patterns, CommunityToolkit.Mvvm Quick Reference Common Service Registration // Services builder.Services.AddSingleton(); builder.Services.AddSingleton(Connectivity.Current); builder.Services.AddSingleton(Geolocation.Default);

// ViewModels (if using MVVM) builder.Services.AddTransient(); builder.Services.AddTransient();

// Pages with DI builder.Services.AddTransient();

Platform Checks // Runtime platform check if (DeviceInfo.Current.Platform == DevicePlatform.iOS) { } if (DeviceInfo.Current.Platform == DevicePlatform.Android) { } if (DeviceInfo.Current.Platform == DevicePlatform.WinUI) { } if (DeviceInfo.Current.Platform == DevicePlatform.macOS) { }

// Compile-time platform check

if ANDROID

// Android-specific code

elif IOS

// iOS-specific code

elif WINDOWS

// Windows-specific code

endif

Navigation Patterns // Blazor navigation (within BlazorWebView) @inject NavigationManager Navigation Navigation.NavigateTo("/details/123");

// MAUI navigation (to other pages) await Navigation.PushAsync(new SettingsPage()); await Shell.Current.GoToAsync("//settings");