Added impl for ApiInformation for Win8/8.1

Disabled SMTC on Win8.1

ZuneShell/Microsoft/WinRT/ApiInformation.cs

@@ -0,0 +1,41 @@
+#if WINDOWS
+
+using Microsoft.Win32;
+using System;
+
+namespace Microsoft.WinRT
+{
+    /// <summary>
+    /// Polyfills for <c>Windows.Foundation.Metadata.ApiInformation</c>
+    /// </summary>
+    internal static class ApiInformation
+    {
+        private static readonly Version Win8Version = new(6, 2, 0, 0);
+        private static readonly Version Win81Version = new(6, 3, 0, 0);
+        private static readonly Version Win10Version = new(10, 0, 0, 0);
+
+        /// <summary>
+        /// Returns <see langword="true"/> or <see langword="false"/> to indicate whether a specified type is present.
+        /// </summary>
+        /// <param name="typeName">
+        /// The namespace-qualified name of the type.
+        /// </param>
+        /// <returns>
+        /// <see langword="true"/> if the specified type is present; otherwise, <see langword="false"/>.
+        /// </returns>
+        public static bool IsTypePresent(string typeName)
+        {
+            if (Environment.OSVersion.Version >= Win10Version)
+            {
+                return Windows.Foundation.Metadata.ApiInformation.IsTypePresent(typeName);
+            }
+            else
+            {
+                var key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\WindowsRuntime\ActivatableClassId\" + typeName, false);
+                return key != null;
+            }
+        }
+    }
+}
+
+#endif

ZuneShell/ZuneUI/OSVersion.cs

@@ -20,5 +20,13 @@ namespace ZuneUI
                 return true;
             return Environment.OSVersion.Version.Major == 6 && Environment.OSVersion.Version.Minor >= 1;
         }
+
+#if NET6_0_OR_GREATER
+        public static bool IsLessThanWin8() => !OperatingSystem.IsWindowsVersionAtLeast(6, 2);
+
+        public static bool IsLessThanWin81() => !OperatingSystem.IsWindowsVersionAtLeast(6, 3);
+
+        public static bool IsLessThanWin10() => !OperatingSystem.IsWindowsVersionAtLeast(10, 0);
+#endif
     }
 }

ZuneShell/ZuneUI/TransportControls.cs

@@ -826,8 +826,11 @@ namespace ZuneUI
                 }
 
 #if WINDOWS
-                if (Windows.Foundation.Metadata.ApiInformation.IsTypePresent("Windows.Media.SystemMediaTransportControls"))
+                if (Microsoft.WinRT.ApiInformation.IsTypePresent("Windows.Media.SystemMediaTransportControls")
+                    && !OSVersion.IsLessThanWin10())
                 {
+                    // Windows 8.1 doesn't seem to support non-Metro apps using this API.
+
                     // On Windows 8.1 / 10 / 11
                     var _systemMediaTransportControls = Windows.Media.SystemMediaTransportControlsInterop.GetForWindow(Application.Window.Handle);
                     _systemMediaTransportControls.PlaybackStatus = stateNew switch
@@ -1770,7 +1773,7 @@ namespace ZuneUI
 
                         // Use SMTC when available
 #if WINDOWS
-                        if (Windows.Foundation.Metadata.ApiInformation.IsTypePresent("Windows.Media.SystemMediaTransportControls"))
+                        if (Microsoft.WinRT.ApiInformation.IsTypePresent("Windows.Media.SystemMediaTransportControls"))
                         {
                             // On Windows 8.1 / 10 / 11
                             var _systemMediaTransportControls = Windows.Media.SystemMediaTransportControlsInterop.GetForWindow(Application.Window.Handle);