Merge pull request #97 from twsouthwick/blazor

Enable progress bar, images, and breadcrumb navigation in Blazor

sample/HotUI.Blazor.Sample/Startup.cs

@@ -1,14 +1,9 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
+using HotUI.Blazor.Sample.Data;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
-using Microsoft.AspNetCore.HttpsPolicy;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
-using HotUI.Blazor.Sample.Data;
 
 namespace HotUI.Blazor.Sample
 {
@@ -25,6 +20,7 @@ namespace HotUI.Blazor.Sample
         // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
         public void ConfigureServices(IServiceCollection services)
         {
+            services.AddHotUI();
             services.AddRazorPages();
             services.AddServerSideBlazor();
             services.AddSingleton<WeatherForecastService>();
@@ -48,6 +44,7 @@ namespace HotUI.Blazor.Sample
             app.UseStaticFiles();
 
             app.UseRouting();
+            app.UseHotUI();
 
             app.UseEndpoints(endpoints =>
             {

sample/HotUI.Samples/ListViewDetails.cs

@@ -4,15 +4,15 @@ using HotUI.Samples.Models;
 namespace HotUI.Samples {
 	public class ListViewDetails : View {
 		[State]
-		Song song;
+		readonly Song song;
 		public ListViewDetails (Song song)
 		{
 			this.song = song;
 			Body = () => new VStack {
-				new Image(song.ArtworkUrl),
-				new Text(song.Title),
-				new Text(song.Artist),
-				new Text(song.Album),
+				new Image(() => song.ArtworkUrl),
+				new Text(() => song.Title),
+				new Text(() => song.Artist),
+				new Text(() => song.Album),
 			};
 		}
 	}

src/HotUI.Blazor/BlazorExtensions.cs

@@ -1,15 +1,9 @@
 using HotUI.Blazor.Handlers;
-using Microsoft.AspNetCore.Components.RenderTree;
 
 namespace HotUI.Blazor
 {
     internal static class BlazorExtensions
     {
-        static BlazorExtensions()
-        {
-            UI.Init();
-        }
-
         public static IBlazorViewHandler GetOrCreateViewHandler(this View view)
         {
             if (view == null)

src/HotUI.Blazor/Components/BImage.razor

@@ -0,0 +1,10 @@
+@inherits HotUIComponentBase
+
+<span class="hotui-img">
+    <img src="@Url" />
+</span>
+
+@code {
+    [Parameter]
+    public string Url { get; set; }
+}

src/HotUI.Blazor/Components/BLabel.razor

@@ -1,8 +1,8 @@
 @inherits HotUIComponentBase
 
-<span class="hotui-label">
+<div class="hotui-label">
     <p>@Value</p>
-</span>
+</div>
 
 @code {
     [Parameter]

src/HotUI.Blazor/Components/BProgressBar.razor

@@ -0,0 +1,22 @@
+@inherits HotUIComponentBase
+
+@if (IsIndeterminate)
+{
+    <div class="hotui-progress progress">
+        <div class="progress-bar progress-bar-striped progress-bar-animated" role="progressbar" style="width: 100%" aria-valuenow="100" aria-valuemin="0" aria-valuemax="100" />
+    </div>
+}
+else
+{
+    <div class="hotui-progress progress">
+        <div class="progress-bar" role="progressbar" style="width: @Value%" aria-valuenow="@Value" aria-valuemin="0" aria-valuemax="100" />
+    </div>
+}
+
+@code {
+    [Parameter]
+    public double Value { get; set; }
+
+    [Parameter]
+    public bool IsIndeterminate { get; set; }
+}

src/HotUI.Blazor/Components/BView.cs

@@ -16,18 +16,26 @@ namespace HotUI.Blazor.Components
             // Check if unsupported as this can cause infinite recursion if not checked
             if (View.IsIUnsupportednternalView())
             {
-                builder.AddContent(2, $"Unsupported view: {View.GetType()}");
+                builder.OpenElement(2, "div");
+                builder.AddAttribute(3, "class", "alert alert-warning");
+                builder.AddAttribute(4, "role", "alert");
+                builder.AddMarkupContent(5, $"Unsupported view: <b>{View.GetType()}</b>");
+                builder.CloseElement();
             }
             else if (View?.GetOrCreateViewHandler() is IBlazorViewHandler handler)
             {
-                builder.OpenComponent(3, handler.Component);
+                builder.OpenComponent(6, handler.Component);
                 builder.SetKey(handler);
                 builder.AddComponentReferenceCapture(4, handler.OnComponentLoad);
                 builder.CloseComponent();
             }
             else
             {
-                builder.AddContent(5, "Error: No view");
+                builder.OpenElement(7, "div");
+                builder.AddAttribute(8, "class", "alert alert-danger");
+                builder.AddAttribute(9, "role", "alert");
+                builder.AddMarkupContent(10, $"Invalid view handler: <b>{View.GetType()}</b>");
+                builder.CloseElement();
             }
 
             builder.CloseElement();

src/HotUI.Blazor/Components/HotUIComponentBase.cs

@@ -8,6 +8,6 @@ namespace HotUI.Blazor.Components
         {
         }
 
-        internal void NotifyUpdate() => base.StateHasChanged();
+        internal void NotifyUpdate() => Invoke(StateHasChanged);
     }
 }

src/HotUI.Blazor/Handlers/ImageHandler.cs

@@ -0,0 +1,24 @@
+using HotUI.Blazor.Components;
+
+namespace HotUI.Blazor.Handlers
+{
+    internal class ImageHandler : BlazorHandler<Image, BImage>
+    {
+        public static readonly PropertyMapper<Image> Mapper = new PropertyMapper<Image>
+        {
+            { nameof(Image.Bitmap), MapBitmapProperty },
+        };
+
+        public ImageHandler()
+            : base(Mapper)
+        {
+        }
+
+        public static void MapBitmapProperty(IViewHandler viewHandler, Image virtualView)
+        {
+            var nativeView = (BImage)viewHandler.NativeView;
+
+            nativeView.Url = (string)virtualView.Bitmap.NativeBitmap;
+        }
+    }
+}

src/HotUI.Blazor/Handlers/ProgressBarHandler.cs

@@ -0,0 +1,34 @@
+using System;
+using HotUI.Blazor.Components;
+
+namespace HotUI.Blazor.Handlers
+{
+    internal class ProgressBarHandler : BlazorHandler<ProgressBar, BProgressBar>
+    {
+        public static readonly PropertyMapper<ProgressBar> Mapper = new PropertyMapper<ProgressBar>
+        {
+            { nameof(ProgressBar.Value), MapValueProperty },
+            { nameof(ProgressBar.IsIndeterminate), MapIsIndeterminateProperty }
+        };
+        
+        public ProgressBarHandler()
+            : base(Mapper)
+        {
+        }
+
+        public static void MapValueProperty(IViewHandler viewHandler, ProgressBar virtualView)
+        {
+            var nativeView = (BProgressBar)viewHandler.NativeView;
+            
+            nativeView.Value = virtualView.Value;
+        }
+
+
+        private static void MapIsIndeterminateProperty(IViewHandler viewHandler, ProgressBar virtualView)
+        {
+            var nativeView = (BProgressBar)viewHandler.NativeView;
+
+            nativeView.IsIndeterminate = virtualView.IsIndeterminate;
+        }
+    }
+}

src/HotUI.Blazor/HotUIExtensions.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace HotUI.Blazor
+{
+    public static class HotUIExtensions
+    {
+        public static void AddHotUI(this IServiceCollection services)
+        {
+            UI.Init();
+
+            services.AddImages();
+        }
+
+        public static void UseHotUI(this IApplicationBuilder app)
+        {
+            app.UseImages();
+        }
+    }
+}

src/HotUI.Blazor/HotUIPage.razor

@@ -1,20 +1,24 @@
 @using HotUI.Blazor.Components
 
-    <div class="hotui-page">
-        @if (_views.Any())
-        {
-            <button class="btn btn-link" @onclick="@Back">Back</button>
-        }
-        else
-        {
-            <button class="btn btn-link" @onclick="@Back" disabled>Back</button>
-        }
-        <br />
-        <BView @key="@View" View="@View" />
-    </div>
+<div class="hotui-page">
+    <nav aria-label="breadcrumb">
+        <ol class="breadcrumb">
+            @foreach (var view in _navigationStack.Reverse())
+            {
+                <li class="breadcrumb-item" aria-current="page">
+                    <a href="#" @onclick="@(()=>Back(view))">@GetTitle(view)</a>
+                </li>
+            }
+
+            <li class="breadcrumb-item active" aria-current="page">@GetTitle(View)</li>
+        </ol>
+    </nav>
+    <br />
+    <BView @key="@View" View="@View" />
+</div>
 
 @code {
-    private Stack<View> _views = new Stack<View>();
+    private readonly Stack<View> _navigationStack = new Stack<View>();
     private View _view;
 
     [Parameter]
@@ -31,7 +35,7 @@
             {
                 nav.PerformNavigate = toView =>
                 {
-                    _views.Push(View);
+                    _navigationStack.Push(View);
                     View = toView;
                     StateHasChanged();
                 };
@@ -39,9 +43,22 @@
         }
     }
 
-    private void Back()
+    private string GetTitle(View view)
     {
-        View = _views.Pop();
-        StateHasChanged();
+        return view.GetEnvironment<string>(EnvironmentKeys.View.Title) ?? "Unnamed page";
+    }
+
+    private void Back(View view)
+    {
+        while (_navigationStack.Any())
+        {
+            View = _navigationStack.Pop();
+
+            if (View == view)
+            {
+                StateHasChanged();
+                return;
+            }
+        }
     }
 }

src/HotUI.Blazor/Middleware/Images/BitmapExtensions.cs

@@ -0,0 +1,27 @@
+using HotUI.Blazor.Middleware.Images;
+using HotUI.Services;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace HotUI.Blazor
+{
+    internal static class BitmapExtensions
+    {
+        public static void AddImages(this IServiceCollection services)
+        {
+            services.AddSingleton<BitmapRepository>();
+            services.AddSingleton<IBitmapService, BlazorBitmapService>();
+            services.AddHttpClient<BitmapMiddleware>();
+        }
+
+        public static void UseImages(this IApplicationBuilder app)
+        {
+            Device.BitmapService = app.ApplicationServices.GetRequiredService<IBitmapService>();
+
+            app.Map(BlazorBitmap.Prefix, app2 =>
+            {
+                app2.UseMiddleware<BitmapMiddleware>();
+            });
+        }
+    }
+}

src/HotUI.Blazor/Middleware/Images/BitmapMiddleware.cs

@@ -0,0 +1,57 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.Logging;
+using System.Net.Http;
+using System.Threading.Tasks;
+
+namespace HotUI.Blazor.Middleware.Images
+{
+    internal class BitmapMiddleware : IMiddleware
+    {
+        private readonly HttpClient _client;
+        private readonly BitmapRepository _repository;
+        private readonly ILogger<BitmapMiddleware> _logger;
+
+        public BitmapMiddleware(HttpClient client, BitmapRepository repository, ILogger<BitmapMiddleware> logger)
+        {
+            _client = client;
+            _repository = repository;
+            _logger = logger;
+        }
+
+        public Task InvokeAsync(HttpContext context, RequestDelegate next)
+        {
+            if (_repository.TryMatch(context.Request.Path, out var url))
+            {
+                return ProxyImageAsync(context, url);
+            }
+            else
+            {
+                context.Response.StatusCode = 404;
+                return Task.CompletedTask;
+            }
+        }
+
+        private async Task ProxyImageAsync(HttpContext context, string url)
+        {
+            using (var result = await _client.GetAsync(url, HttpCompletionOption.ResponseHeadersRead).ConfigureAwait(false))
+            {
+                if (!result.IsSuccessStatusCode)
+                {
+                    _logger.LogInformation("Could not find image at {Url}", url);
+                    context.Response.StatusCode = 404;
+                    return;
+                }
+                else
+                {
+                    context.Response.StatusCode = 200;
+                    context.Response.ContentType = result.Content.Headers.ContentType.MediaType;
+
+                    using (var stream = await result.Content.ReadAsStreamAsync())
+                    {
+                        await stream.CopyToAsync(context.Response.Body, context.RequestAborted).ConfigureAwait(false);
+                    }
+                }
+            }
+        }
+    }
+}

src/HotUI.Blazor/Middleware/Images/BitmapRepository.cs

@@ -0,0 +1,31 @@
+using Microsoft.AspNetCore.Http;
+using System;
+using System.Collections.Concurrent;
+
+namespace HotUI.Blazor.Middleware.Images
+{
+    internal class BitmapRepository
+    {
+        private readonly ConcurrentDictionary<string, string> _repository;
+
+        public BitmapRepository()
+        {
+            _repository = new ConcurrentDictionary<string, string>(StringComparer.Ordinal);
+        }
+
+        public void Add(BlazorBitmap bitmap)
+        {
+            _repository.TryAdd(bitmap.Id, bitmap.Url);
+        }
+
+        public void Remove(BlazorBitmap bitmap)
+        {
+            _repository.TryRemove(bitmap.Id, out _);
+        }
+
+        public bool TryMatch(PathString path, out string url)
+        {
+            return _repository.TryGetValue(path.Value.Substring(1), out url);
+        }
+    }
+}

src/HotUI.Blazor/Middleware/Images/BlazorBitmap.cs

@@ -0,0 +1,46 @@
+using HotUI.Graphics;
+using Microsoft.AspNetCore.Http;
+using System;
+using System.Diagnostics;
+
+namespace HotUI.Blazor
+{
+    internal class BlazorBitmap : Bitmap
+    {
+        public static readonly PathString Prefix = "/hotui/blazor/image";
+
+        private readonly Action<BlazorBitmap> _remove;
+
+        public BlazorBitmap(string url, Action<BlazorBitmap> remove)
+        {
+            Url = url;
+            Id = GenerateId();
+            _remove = remove;
+        }
+
+        public string LocalUrl => $"{Prefix}/{Id}";
+
+        public string Id { get; }
+
+        public string Url { get; }
+
+        public override SizeF Size => default;
+
+        public override object NativeBitmap => LocalUrl;
+
+        protected override void DisposeNative()
+        {
+            _remove(this);
+        }
+
+        private static string GenerateId()
+        {
+            var guid = Guid.NewGuid();
+            Span<byte> bytes = stackalloc byte[16];
+            Debug.Assert(guid.TryWriteBytes(bytes));
+
+            // Remove any padding done with '='
+            return Convert.ToBase64String(bytes).TrimEnd('=');
+        }
+    }
+}

src/HotUI.Blazor/Middleware/Images/BlazorBitmapService.cs

@@ -0,0 +1,29 @@
+using HotUI.Graphics;
+using HotUI.Services;
+using System.Threading.Tasks;
+
+namespace HotUI.Blazor.Middleware.Images
+{
+    internal class BlazorBitmapService : IBitmapService
+    {
+        private readonly BitmapRepository _repo;
+
+        public BlazorBitmapService(BitmapRepository repo)
+        {
+            _repo = repo;
+        }
+
+        public Task<Bitmap> LoadBitmapAsync(string source)
+        {
+            var bitmap = new BlazorBitmap(source, _repo.Remove);
+
+            _repo.Add(bitmap);
+
+            return Task.FromResult<Bitmap>(bitmap);
+        }
+
+        public Task<Bitmap> LoadBitmapFromFileAsync(string file) => LoadBitmapAsync(file);
+
+        public Task<Bitmap> LoadBitmapFromUrlAsync(string source) => LoadBitmapAsync(source);
+    }
+}

src/HotUI.Blazor/UI.cs

@@ -1,5 +1,4 @@
-using HotUI.Blazor.Components;
-using HotUI.Blazor.Handlers;
+using HotUI.Blazor.Handlers;
 
 namespace HotUI.Blazor
 {
@@ -24,6 +23,8 @@ namespace HotUI.Blazor
             Registrar.Handlers.Register<ListView, ListViewHandler>();
             Registrar.Handlers.Register<Spacer, SpacerHandler>();
             Registrar.Handlers.Register<TextField, TextFieldHandler>();
+            Registrar.Handlers.Register<ProgressBar, ProgressBarHandler>();
+            Registrar.Handlers.Register<Image, ImageHandler>();
 
             Device.PerformInvokeOnMainThread = a => a();
             Device.OnStateChanged = view => () =>