Fixing a crash an and UI issue

.github/workflows/dotnet.yml

@@ -0,0 +1,25 @@
+name: .NET
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v1
+      with:
+        dotnet-version: 5.0.x
+    - name: Restore dependencies
+      run: dotnet restore
+    - name: Build
+      run: dotnet build --no-restore
+    - name: Test
+      run: dotnet test --no-build --verbosity normal

.gitignore

@@ -1,196 +1,6 @@
-## Ignore Visual Studio temporary files, build results, and
-## files generated by popular Visual Studio add-ons.
-
-# User-specific files
-*.suo
-*.user
-*.sln.docstates
-
-# Build results
-[Dd]ebug/
-[Dd]ebugPublic/
-[Rr]elease/
-x64/
-build/
-bld/
-[Bb]in/
-[Oo]bj/
-
-# Roslyn cache directories
-*.ide/
-
-# MSTest test Results
-[Tt]est[Rr]esult*/
-[Bb]uild[Ll]og.*
-
-#NUNIT
-*.VisualState.xml
-TestResult.xml
-
-# Build Results of an ATL Project
-[Dd]ebugPS/
-[Rr]eleasePS/
-dlldata.c
-
-*_i.c
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-*.ilk
-*.meta
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-
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-
-# TFS 2012 Local Workspace
-$tf/
-
-# Guidance Automation Toolkit
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-
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-*.[Rr]e[Ss]harper
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-
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-.JustCode
-
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-_TeamCity*
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-*.dotCover
-
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-
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-
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-
-# DocProject is a documentation generator add-in
-DocProject/buildhelp/
-DocProject/Help/*.HxT
-DocProject/Help/*.HxC
-DocProject/Help/*.hhc
-DocProject/Help/*.hhk
-DocProject/Help/*.hhp
-DocProject/Help/Html2
-DocProject/Help/html
-
-# Click-Once directory
-publish/
-
-# Publish Web Output
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-
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-packages/*
-## TODO: If the tool you use requires repositories.config
-## uncomment the next line
-#!packages/repositories.config
-
-# Enable "build/" folder in the NuGet Packages folder since
-# NuGet packages use it for MSBuild targets.
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-!packages/build/
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-
-# Others
-sql/
-*.Cache
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-[Ss]tyle[Cc]op.*
-~$*
-*~
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-node_modules/
-bower_components/
-
-# RIA/Silverlight projects
-Generated_Code/
-
-# Backup & report files from converting an old project file
-# to a newer Visual Studio version. Backup files are not needed,
-# because we have git ;-)
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-
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-
-Thumbs.db
-/.vs
-/.vs
-/.vs/slnx.sqlite
-/.vs/ProjectSettings.json
+**/.vs/
+**/.vscode/
+**/bin/
+**/obj/
+**/Properties/*
+**/*.user

Extensions.cs

@@ -0,0 +1,59 @@
+using Microsoft.Win32;
+using System;
+
+namespace WebPageScreensaver
+{
+    public static class Extensions
+    {
+        public static RegistryKey GetOrCreateSubKey(this RegistryKey root, string subKeyName)
+        {
+            if (root == null)
+            {
+                throw new ArgumentNullException(nameof(root));
+            }
+            if (string.IsNullOrWhiteSpace(subKeyName))
+            {
+                throw new ArgumentException($"Argument is null or whitespace: {nameof(subKeyName)}");
+            }
+
+            RegistryKey? key = root.OpenSubKey(subKeyName, writable: true);
+            if (key == null)
+            {
+                key = root.CreateSubKey(subKeyName, writable: true);
+                if (key == null)
+                {
+                    throw new UnauthorizedAccessException($"Could not get/create key to registry: {subKeyName}");
+                }
+            }
+            return key;
+        }
+
+        public static string GetOrCreateValue<T>(this RegistryKey root, string valueName, T defaultValue)
+        {
+            if (root == null)
+            {
+                throw new ArgumentNullException(nameof(root));
+            }
+            if (defaultValue == null)
+            {
+                throw new ArgumentNullException(nameof(defaultValue));
+            }
+            if (string.IsNullOrWhiteSpace(valueName))
+            {
+                throw new ArgumentNullException(nameof(valueName));
+            }
+
+            object? obj = root.GetValue(valueName);
+            if (obj == null)
+            {
+                root.SetValue(valueName, defaultValue);
+                obj = root.GetValue(valueName);
+                if (obj == null)
+                {
+                    throw new UnauthorizedAccessException($"Could not get/create the registry value: {valueName}");
+                }
+            }
+            return obj.ToString() ?? string.Empty;
+        }
+    }
+}

MultiFormContext.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using System.Windows.Forms;
+
+namespace WebPageScreensaver
+{
+    internal class MultiFormContext : ApplicationContext
+    {
+        public MultiFormContext(List<Form> forms)
+        {
+            if (forms == null)
+            {
+                throw new ArgumentNullException(nameof(forms));
+            }
+
+            foreach (Form form in forms)
+            {
+                form.FormClosed += (s, args) => ExitThread();
+                form.Show();
+            }
+        }
+    }
+}

MultiScreenMode.cs

@@ -0,0 +1,23 @@
+namespace WebPageScreensaver
+{
+    /// <summary>
+    /// Specifies the different ways a screensaver can be shown in multiple screens.
+    /// </summary>
+    internal enum MultiScreenMode
+    {
+        /// <summary>
+        /// Same webpage in all screens.
+        /// </summary>
+        Mirror,
+
+        /// <summary>
+        /// Each screen has its own individual list of webpages.
+        /// </summary>
+        Separate,
+
+        /// <summary>
+        /// Show one webpage split among all the screens.
+        /// </summary>
+        Span
+    }
+}