fix: Added the ability to link with Form.

packages/masamune/lib/form/extension.dart

@@ -0,0 +1,56 @@
+part of masamune;
+
+/// Extension methods for [FormMediaValue].
+///
+/// [FormMediaValue]の拡張メソッドです。
+extension FormMediaValueExtensions on FormMediaValue {
+  /// Convert to [ModelImageUri].
+  ///
+  /// If [path] is empty, null is returned.
+  ///
+  /// Returns an error if the original [FormMediaType] is not [FormMediaType.image].
+  ///
+  /// [ModelImageUri]に変換します。
+  ///
+  /// [path]が空の場合はnullを返します。
+  ///
+  /// 元の[FormMediaType]が[FormMediaType.image]でない場合はエラーを返します。
+  ModelImageUri? toModelImageUri() {
+    if (path.isEmpty) {
+      return null;
+    }
+    final uri = Uri.tryParse(path!);
+    if (uri == null) {
+      return null;
+    }
+    if (type != FormMediaType.image) {
+      throw Exception("The original FormMediaType is not FormMediaType.image");
+    }
+    return ModelImageUri(uri);
+  }
+
+  /// Convert to [ModelVideoUri].
+  ///
+  /// If [path] is empty, null is returned.
+  ///
+  /// Returns an error if the original [FormMediaType] is not [FormMediaType.video].
+  ///
+  /// [ModelVideoUri]に変換します。
+  ///
+  /// [path]が空の場合はnullを返します。
+  ///
+  /// 元の[FormMediaType]が[FormMediaType.video]でない場合はエラーを返します。
+  ModelVideoUri? toModelVideoUri() {
+    if (path.isEmpty) {
+      return null;
+    }
+    final uri = Uri.tryParse(path!);
+    if (uri == null) {
+      return null;
+    }
+    if (type != FormMediaType.video) {
+      throw Exception("The original FormMediaType is not FormMediaType.video");
+    }
+    return ModelVideoUri(uri);
+  }
+}

packages/masamune/lib/masamune.dart

@@ -40,6 +40,7 @@ export 'package:masamune_annotation/masamune_annotation.dart';
 export 'package:meta/meta.dart' show useResult;
 
 part 'form/form_scoped_widget.dart';
+part 'form/extension.dart';
 part 'model/model.dart';
 part 'model/extension.dart';
 part 'prefs/prefs.dart';

packages/masamune/lib/model/extension.dart

@@ -14,4 +14,39 @@ extension ModelImageUriExtensions on ModelImageUri {
   ImageProvider image([String defaultAssetURI = "assets/image.png"]) {
     return Asset.image(value.toString(), defaultAssetURI);
   }
+
+  /// Convert to [FormMediaValue].
+  ///
+  /// If [value] is empty, null is returned.
+  ///
+  /// [FormMediaValue]に変換します。
+  ///
+  /// [value]が空の場合はnullを返します。
+  FormMediaValue? toFormMediaValue() {
+    final path = value.toString();
+    if (path.isEmpty) {
+      return null;
+    }
+    return FormMediaValue(path: path, type: FormMediaType.image);
+  }
+}
+
+/// Extension methods for [ModelVideoUri].
+///
+/// [ModelVideoUri]の拡張メソッドです。
+extension ModelVideoUriExtensions on ModelVideoUri {
+  /// Convert to [FormMediaValue].
+  ///
+  /// If [value] is empty, null is returned.
+  ///
+  /// [FormMediaValue]に変換します。
+  ///
+  /// [value]が空の場合はnullを返します。
+  FormMediaValue? toFormMediaValue() {
+    final path = value.toString();
+    if (path.isEmpty) {
+      return null;
+    }
+    return FormMediaValue(path: path, type: FormMediaType.video);
+  }
 }

packages/masamune/pubspec.lock

@@ -303,15 +303,15 @@ packages:
       path: "../katana_model"
       relative: true
     source: path
-    version: "2.4.0"
+    version: "2.5.0"
   katana_model_local:
     dependency: "direct main"
     description:
       name: katana_model_local
-      sha256: "7385af1797643dacdd09604927297012037466766914ce080c80e3440bec5a5e"
+      sha256: "08f44756c97ab70d5de4a75294e6757ad0f731ddbdc42de8f0b979a8307eab30"
       url: "https://pub.dev"
     source: hosted
-    version: "2.1.2"
+    version: "2.2.0"
   katana_prefs:
     dependency: "direct main"
     description: