新增毛玻璃主题

lib/widgets/app_overlay.dart

@@ -0,0 +1,102 @@
+import 'dart:ui' as ui;
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import '../providers/app_provider.dart';
+
+/// 毛玻璃主题下的通用磨砂面板：真实背景模糊 + 半透明深色
+/// 仅在毛玻璃模式下生效，其余主题直接透传 child，不影响原样式
+class FrostedPanel extends StatelessWidget {
+  final Widget child;
+  final BorderRadiusGeometry borderRadius;
+  final Color color;
+
+  const FrostedPanel({
+    super.key,
+    required this.child,
+    this.borderRadius = BorderRadius.zero,
+    this.color = const Color(0xCC121418),
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final frosted = context.watch<AppProvider>().frostedActive;
+    if (!frosted) return child;
+    return ClipRRect(
+      borderRadius: borderRadius,
+      child: BackdropFilter(
+        filter: ui.ImageFilter.blur(sigmaX: 22, sigmaY: 22),
+        child: ColoredBox(color: color, child: child),
+      ),
+    );
+  }
+}
+
+/// 毛玻璃版底部弹层：毛玻璃模式下自动加磨砂，其余主题与原 showModalBottomSheet 一致
+Future<T?> appModalBottomSheet<T>({
+  required BuildContext context,
+  Color? backgroundColor,
+  Color? barrierColor,
+  double? elevation,
+  ShapeBorder? shape,
+  bool isScrollControlled = false,
+  bool isDismissible = true,
+  bool enableDrag = true,
+  bool useSafeArea = false,
+  bool showDragHandle = false,
+  BoxConstraints? constraints,
+  bool useRootNavigator = false,
+  required WidgetBuilder builder,
+}) {
+  final frosted = context.read<AppProvider>().frostedActive;
+  return showModalBottomSheet(
+    context: context,
+    backgroundColor: frosted ? Colors.transparent : backgroundColor,
+    barrierColor: barrierColor,
+    elevation: elevation,
+    shape: shape,
+    isScrollControlled: isScrollControlled,
+    isDismissible: isDismissible,
+    enableDrag: enableDrag,
+    useSafeArea: useSafeArea,
+    showDragHandle: showDragHandle,
+    constraints: constraints,
+    useRootNavigator: useRootNavigator,
+    builder: (ctx) {
+      final content = builder(ctx);
+      if (!frosted) return content;
+      return FrostedPanel(
+        borderRadius: const BorderRadius.vertical(top: Radius.circular(20)),
+        child: content,
+      );
+    },
+  );
+}
+
+/// 毛玻璃版对话框：毛玻璃模式下自动加磨砂
+Future<T?> appDialog<T>({
+  required BuildContext context,
+  bool barrierDismissible = true,
+  Color? barrierColor,
+  bool useSafeArea = true,
+  RouteSettings? routeSettings,
+  bool useRootNavigator = true,
+  required WidgetBuilder builder,
+}) {
+  final frosted = context.read<AppProvider>().frostedActive;
+  return showDialog(
+    context: context,
+    barrierDismissible: barrierDismissible,
+    barrierColor: barrierColor,
+    useSafeArea: useSafeArea,
+    routeSettings: routeSettings,
+    useRootNavigator: useRootNavigator,
+    builder: (ctx) {
+      final content = builder(ctx);
+      if (!frosted) return content;
+      return FrostedPanel(
+        borderRadius: BorderRadius.circular(20),
+        child: content,
+      );
+    },
+  );
+}