Schedule: mouse drag scrolls the board sideways only; wheel stays vertical

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/desktop/lib/src/schedule/ui/schedule_card.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 
 import '../schedule_model.dart';
@@ -100,7 +101,12 @@ class DayColumn extends StatelessWidget {
                   ? Center(
                       child: Text('—', style: TextStyle(color: scheme.onSurfaceVariant)),
                     )
-                  : ListView.separated(
+                  // The board's mouse drag is sideways only: a column scrolls by
+                  // wheel (or touch), never by dragging the mouse.
+                  : ScrollConfiguration(
+                      behavior: ScrollConfiguration.of(context)
+                          .copyWith(dragDevices: {...PointerDeviceKind.values}..remove(PointerDeviceKind.mouse)),
+                      child: ListView.separated(
                         padding: const EdgeInsets.fromLTRB(8, 0, 8, 10),
                         itemCount: cards.length,
                         separatorBuilder: (_, _) => SizedBox(height: compact ? 6 : 10),
@@ -108,6 +114,7 @@ class DayColumn extends StatelessWidget {
                       ),
                     ),
             ),
+          ),
         ],
       ),
     );

apps/desktop/lib/src/schedule/ui/schedule_page.dart

@@ -501,6 +501,7 @@ class _SchedulePageState extends State<SchedulePage> {
       (byDay[DateTime(l.year, l.month, l.day)] ??= []).add(e);
     }
     return HScroll(
+      wheel: false,
       controller: _scroll,
       builder: (c) => ListView.separated(
         key: const ValueKey('schedule-board'),

apps/desktop/lib/src/shell/motion.dart

@@ -89,7 +89,11 @@ Future<T?> showPopover<T>(
 class HScroll extends StatefulWidget {
   final ScrollController? controller;
   final Widget Function(ScrollController controller) builder;
-  const HScroll({super.key, this.controller, required this.builder});
+  /// Map the plain (vertical) wheel to sideways scrolling. Off where the
+  /// children scroll vertically themselves (the schedule's day columns):
+  /// there only mouse drag and Shift+wheel move sideways.
+  final bool wheel;
+  const HScroll({super.key, this.controller, required this.builder, this.wheel = true});
 
   @override
   State<HScroll> createState() => _HScrollState();
@@ -121,6 +125,6 @@ class _HScrollState extends State<HScroll> {
   Widget build(BuildContext context) => ScrollConfiguration(
         behavior: ScrollConfiguration.of(context)
             .copyWith(dragDevices: PointerDeviceKind.values.toSet()),
-        child: Listener(onPointerSignal: _wheel, child: widget.builder(_c)),
+        child: widget.wheel ? Listener(onPointerSignal: _wheel, child: widget.builder(_c)) : widget.builder(_c),
       );
 }