fix use after dispose error from videos

Fixes #169

lib/widgets/players/video.dart

@@ -38,30 +38,19 @@ class const VideoPlayer(
       return player.dispose;
     }, []);
 
-    final aspectRatio = switch (info) {
-      VideoInfo(:final width?, :final height?) when width > 0 && height > 0 =>
-        width / height,
-      _ => 16 / 9,
-    };
-
-    return ConstrainedBox(
-      constraints: const .new(maxHeight: 300),
-      child: AspectRatio(
-        aspectRatio: aspectRatio,
-        child: ClipRRect(
-          borderRadius: .circular(12),
-          child: Video(
-            controller: controller,
-            controls: (_) =>
+    final controls = useCallback(
+      (VideoState _) =>
           // Until media_kit moves to material_ui, this Material is needed.
           Material(
             type: .transparency,
-                  child: Stack(
+            child: ValueListenableBuilder(
+              valueListenable: loaded,
+              builder: (_, loaded, _) => Stack(
                 children: [
                   Positioned.fill(
                     child: GestureDetector(
                       behavior: .opaque,
-                          onTap: loaded.value ? player.playOrPause : null,
+                      onTap: loaded ? player.playOrPause : null,
                     ),
                   ),
                   Positioned(
@@ -98,7 +87,7 @@ class const VideoPlayer(
                         padding: const .only(left: 4, right: 4, top: 16),
                         child: PlayerControls(
                           player,
-                              loading: !loaded.value,
+                          loading: !loaded,
                           size: info?.size,
                           color: Colors.white,
                           actions: .new([
@@ -107,8 +96,7 @@ class const VideoPlayer(
                                 final fullscreen = isFullscreen(context);
 
                                 return IconButton(
-                                      onPressed: () =>
-                                          toggleFullscreen(context),
+                                  onPressed: () => toggleFullscreen(context),
                                   color: Colors.white,
                                   tooltip: fullscreen
                                       ? "Exit fullscreen"
@@ -130,6 +118,22 @@ class const VideoPlayer(
               ),
             ),
           ),
+      [uri, encrypted, filename, info],
+    );
+
+    final aspectRatio = switch (info) {
+      VideoInfo(:final width?, :final height?) when width > 0 && height > 0 =>
+        width / height,
+      _ => 16 / 9,
+    };
+
+    return ConstrainedBox(
+      constraints: const .new(maxHeight: 300),
+      child: AspectRatio(
+        aspectRatio: aspectRatio,
+        child: ClipRRect(
+          borderRadius: .circular(12),
+          child: Video(controller: controller, controls: controls),
         ),
       ),
     );