Implemented editor providers.

Progrart/App.axaml.cs

@@ -6,6 +6,7 @@ using System.Linq;
 using Avalonia.Markup.Xaml;
 using Progrart.Views;
 using Progrart.Icons;
+using Progrart.Pages;
 
 namespace Progrart;
 
@@ -19,12 +20,22 @@ public partial class App : Application
 
 	public override void OnFrameworkInitializationCompleted()
 	{
+		IconProvider.Register(new DefaultIconProvider());
+		EditorProvider.Register("text", "Default Text Editor", typeof(EditorPage));
+		EditorProvider.BindFileType("cs", "text");
+		EditorProvider.BindFileType("c", "text");
+		EditorProvider.BindFileType("cpp", "text");
+		EditorProvider.BindFileType("h", "text");
+		EditorProvider.BindFileType("hpp", "text");
+		EditorProvider.BindFileType("txt", "text");
+		EditorProvider.BindFileType("cpp", "text");
+		EditorProvider.BindFileType("json", "text");
+		EditorProvider.BindFileType("sh", "text");
 		if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
 		{
 			// Avoid duplicate validations from both Avalonia and the CommunityToolkit. 
 			// More info: https://docs.avaloniaui.net/docs/guides/development-guides/data-validation#manage-validationplugins
 			isDesktop = true;
-			IconProvider.Register(new DefaultIconProvider());
 			DisableAvaloniaDataAnnotationValidation();
 			desktop.MainWindow = new MainWindow();
 		}

Progrart/Controls/FileItem.axaml

@@ -10,7 +10,7 @@
 
 				<Button.ContextMenu>
 					<ContextMenu>
-						<MenuItem Header="_Open"/>
+						<MenuItem Header="_Open" Name="OpenFileMenuItem"/>
 						<MenuItem Header="_Delete"/>
 					</ContextMenu>
 				</Button.ContextMenu>

Progrart/Controls/FileItem.axaml.cs

@@ -2,7 +2,9 @@ using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Markup.Xaml;
 using Avalonia.Platform.Storage;
+using Progrart.Controls.TabSystem;
 using Progrart.Icons;
+using Progrart.Pages;
 using System.Threading.Tasks;
 
 namespace Progrart.Controls;
@@ -11,6 +13,7 @@ public partial class FileItem : UserControl
 {
 	IStorageItem currentItem;
 	bool isOpen = false;
+	string extension = "";
 	public FileItem(IStorageItem storageItem)
 	{
 		InitializeComponent();
@@ -29,7 +32,7 @@ public partial class FileItem : UserControl
 			var dotIndex = file.Name.LastIndexOf('.');
 			if (dotIndex >= 0)
 			{
-				var extension = file.Name[(dotIndex + 1)..];
+				extension = file.Name[(dotIndex + 1)..];
 				if (IconProvider.TryGetIcon(extension, out var icon))
 				{
 					GenericFileIcon.IsVisible = false;
@@ -41,20 +44,45 @@ public partial class FileItem : UserControl
 		NameBlock.Text = storageItem.Name;
 		MainButton.DoubleTapped += async (_, _) =>
 		{
-			if (currentItem is IStorageFolder folder)
+			await OpenItem();
+		};
+		OpenFileMenuItem.Click += async (a, b) =>
+		{
+			await OpenItem();
+		};
+	}
+	async Task OpenItem()
+	{
+
+		if (currentItem is IStorageFolder folder)
+		{
+			if (isOpen)
 			{
-				if (isOpen)
+				RemoveAll();
+				isOpen = false;
+			}
+			else
+			{
+				isOpen = true;
+				await LoadAll(folder);
+			}
+		}
+		else
+			if (currentItem is IStorageFile file)
+			{
+
+				if (EditorProvider.TryGetEditor(extension, out var page))
 				{
-					RemoveAll();
-					isOpen = false;
-				}
-				else
-				{
-					isOpen = true;
-					await LoadAll(folder);
+					if (page is ITabPage editor)
+					{
+						if (page is IEditorPage editor_page)
+						{
+							editor_page.LoadDocument(file);
+						}
+						EditorProvider.OpenEditor(editor);
+					}
 				}
 			}
-		};
 	}
 	async Task LoadAll(IStorageFolder folder)
 	{

Progrart/Controls/TabSystem/ITabPage.cs

@@ -9,7 +9,5 @@ namespace Progrart.Controls.TabSystem
 		void SetHost(TabHost host);
 		void BindButton(TabButton button);
 		bool IsModified();
-		void Save();
-		void Execute();
 	}
 }

Progrart/Pages/EditorPage.axaml

@@ -5,7 +5,7 @@
 			 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 			 mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
 			 x:Class="Progrart.Pages.EditorPage">
-	<avaloniaedit:TextEditor Name="CodePane" Text="" SyntaxHighlighting="JavaScript"
+	<avaloniaedit:TextEditor Name="CodeEditBox" Text="" SyntaxHighlighting="JavaScript"
 							 ShowLineNumbers="True"
-							 FontFamily="Cascadia Code,Consolas,Menlo,Monospace"/>
+							 FontFamily="Sarasa Mono Slab CL,Cascadia Code,Consolas,Menlo,Monospace"/>
 </UserControl>

Progrart/Pages/EditorPage.axaml.cs

@@ -1,11 +1,15 @@
 using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Markup.Xaml;
+using Avalonia.Platform.Storage;
+using Avalonia.Threading;
 using Progrart.Controls.TabSystem;
+using System.IO;
+using System.Threading.Tasks;
 
 namespace Progrart.Pages;
 
-public partial class EditorPage : UserControl, ITabPage
+public partial class EditorPage : UserControl, ITabPage, IEditorPage
 {
 	public EditorPage()
 	{
@@ -14,7 +18,7 @@ public partial class EditorPage : UserControl, ITabPage
 
 	public void BindButton(TabButton button)
 	{
-		button.Title="Editor Page";
+		button.Title = "Editor Page";
 	}
 
 	public void Execute()
@@ -26,6 +30,20 @@ public partial class EditorPage : UserControl, ITabPage
 		return false;
 	}
 
+	public void LoadDocument(IStorageFile file)
+	{
+		Task.Run(async () =>
+		{
+			using var stream = await file.OpenReadAsync();
+			using StreamReader sr = new StreamReader(stream);
+			var text = sr.ReadToEnd();
+			Dispatcher.UIThread.Invoke(() =>
+			{
+				CodeEditBox.Text = text;
+			});
+		});
+	}
+
 	public void Save()
 	{
 	}

Progrart/Pages/EditorProvider.cs

@@ -0,0 +1,60 @@
+using Avalonia.Controls;
+using Avalonia.Platform.Storage;
+using Progrart.Controls.TabSystem;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
+using System.Text;
+
+namespace Progrart.Pages
+{
+	static public class EditorProvider
+	{
+		static Dictionary<string, string> Names = new();
+		static Dictionary<string, string> ExtensionMapping = new();
+		static Dictionary<string, Type> EditorTypes = new();
+		static TabHost? currentHost = null;
+		public static void setHost(TabHost host)
+		{
+			currentHost = host;
+		}
+		public static void Register(string id, string name, Type t)
+		{
+			Names[id] = name;
+			EditorTypes[id] = t;
+		}
+		public static void BindFileType(string type, string id)
+		{
+			ExtensionMapping[type] = id;
+		}
+		public static void OpenEditor(ITabPage page)
+		{
+			currentHost?.AddPage(page);
+		}
+		public static bool TryGetEditor(string extension, [MaybeNullWhen(false)] out Control editorPage)
+		{
+			if (ExtensionMapping.TryGetValue(extension.ToLower(), out var id))
+			{
+
+				if (EditorTypes.TryGetValue(id, out var editorType))
+				{
+					var obj = Activator.CreateInstance(editorType);
+					if (obj is Control control)
+					{
+						editorPage = control;
+						return true;
+					}
+				}
+			}
+			editorPage = null;
+			return false;
+		}
+	}
+	public interface IEditorPage
+	{
+		void LoadDocument(IStorageFile file);
+		void Save();
+		void Execute();
+	}
+}

Progrart/Views/MainView.axaml.cs

@@ -30,7 +30,7 @@ public partial class MainView : UserControl
 			}
 		};
 		Trace.Listeners.Add(new ConsoleLogger());
-
+		EditorProvider.setHost(MainTabHost);
 		BottomPanelToggle.IsCheckedChanged += (a, b) =>
 		{
 			bool v = BottomPanelToggle.IsChecked == true;