fix tap on chart

lib/screens/overview_screen.dart

@@ -487,6 +487,16 @@ class _OverviewScreenState extends State<OverviewScreen> {
                 : null),
         periodMode: favourite.period,
       ),
+      onChartTap: () => _openChartFilter(
+        context,
+        labelIds: {
+          for (final id in favourite.labelIds) id,
+        },
+        flow: favourite.metric == OverviewMetricMode.labels
+            ? favourite.flow
+            : null,
+        periodMode: favourite.period,
+      ),
     );
   }
 
@@ -609,6 +619,10 @@ class _OverviewScreenState extends State<OverviewScreen> {
             flow: flow ??
                 (_metric == OverviewMetricMode.labels ? _labelFlow : null),
           ),
+          onChartTap: () => _openChartFilter(
+            context,
+            flow: _metric == OverviewMetricMode.labels ? _labelFlow : null,
+          ),
         ),
         const SizedBox(height: 14),
         if (_metric == OverviewMetricMode.flow) ...[
@@ -784,6 +798,34 @@ class _OverviewScreenState extends State<OverviewScreen> {
       ),
     );
   }
+
+  /// Open Transactions with this chart's filters (no specific bar/column).
+  void _openChartFilter(
+    BuildContext context, {
+    Set<String>? labelIds,
+    TxFlowFilter? flow,
+    OverviewPeriodMode? periodMode,
+  }) {
+    final mode = periodMode ?? _period;
+    final yearly = mode == OverviewPeriodMode.yearly;
+    final resolvedLabelIds = labelIds ??
+        {
+          for (final id in _includedLabelIds) id,
+        };
+    Navigator.of(context).push(
+      MaterialPageRoute<void>(
+        builder: (_) => TransactionsScreen(
+          // Monthly charts show a year — open that whole year with the chart filter.
+          initialMonth: yearly ? null : DateTime(_cursor.year, 12),
+          initialYear: yearly ? null : _cursor.year,
+          initialLabelIds: resolvedLabelIds,
+          initialLabelMatch: LabelMatchMode.or,
+          initialFlow: flow,
+          initialSearchInMonthOnly: false,
+        ),
+      ),
+    );
+  }
 }
 
 class _MonthBucket {
@@ -1183,6 +1225,7 @@ class _ChartCard extends StatelessWidget {
     required this.availableLabelCount,
     required this.onLabelTap,
     required this.onMonthTap,
+    required this.onChartTap,
     this.onPeriodModeChanged,
     this.onEdit,
   });
@@ -1211,6 +1254,7 @@ class _ChartCard extends StatelessWidget {
     String? labelId,
     TxFlowFilter? flow,
   }) onMonthTap;
+  final VoidCallback onChartTap;
   final ValueChanged<OverviewPeriodMode>? onPeriodModeChanged;
   final VoidCallback? onEdit;
 
@@ -1551,6 +1595,8 @@ class _ChartCard extends StatelessWidget {
             ],
             SizedBox(
               height: chartHeight,
+              child: _TappableChartArea(
+                onChartTap: onChartTap,
                 child: metric == OverviewMetricMode.flow
                     ? _FlowBars(
                         months: months,
@@ -1558,6 +1604,7 @@ class _ChartCard extends StatelessWidget {
                         currency: currency,
                         period: period,
                         onMonthTap: onMonthTap,
+                        onChartTap: onChartTap,
                       )
                     : _LabelMonthBars(
                         months: months,
@@ -1568,6 +1615,8 @@ class _ChartCard extends StatelessWidget {
                         barStyle: labelBarStyle,
                         invertChart: invertChart,
                         onMonthTap: onMonthTap,
+                        onChartTap: onChartTap,
+                      ),
               ),
             ),
           ],
@@ -1577,6 +1626,69 @@ class _ChartCard extends StatelessWidget {
   }
 }
 
+/// Lets empty-chart taps open the chart filter without double-firing when a bar
+/// was just selected (fl_chart + parent [GestureDetector] both see the tap).
+class _TappableChartArea extends StatefulWidget {
+  const _TappableChartArea({
+    required this.onChartTap,
+    required this.child,
+  });
+
+  final VoidCallback onChartTap;
+  final Widget child;
+
+  @override
+  State<_TappableChartArea> createState() => _TappableChartAreaState();
+}
+
+class _TappableChartAreaState extends State<_TappableChartArea> {
+  var _handling = false;
+
+  void _runExclusive(VoidCallback action) {
+    if (_handling) return;
+    _handling = true;
+    action();
+    Future<void>.delayed(const Duration(milliseconds: 400), () {
+      if (mounted) _handling = false;
+    });
+  }
+
+  void openChartFilter() => _runExclusive(widget.onChartTap);
+
+  void openBar(VoidCallback action) => _runExclusive(action);
+
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      behavior: HitTestBehavior.opaque,
+      onTap: openChartFilter,
+      child: _ChartTapScope(
+        openChartFilter: openChartFilter,
+        openBar: openBar,
+        child: widget.child,
+      ),
+    );
+  }
+}
+
+class _ChartTapScope extends InheritedWidget {
+  const _ChartTapScope({
+    required this.openChartFilter,
+    required this.openBar,
+    required super.child,
+  });
+
+  final VoidCallback openChartFilter;
+  final void Function(VoidCallback action) openBar;
+
+  static _ChartTapScope? maybeOf(BuildContext context) {
+    return context.getInheritedWidgetOfExactType<_ChartTapScope>();
+  }
+
+  @override
+  bool updateShouldNotify(_ChartTapScope oldWidget) => false;
+}
+
 class _FlowBars extends StatelessWidget {
   const _FlowBars({
     required this.months,
@@ -1584,6 +1696,7 @@ class _FlowBars extends StatelessWidget {
     required this.currency,
     required this.period,
     required this.onMonthTap,
+    required this.onChartTap,
   });
 
   final List<DateTime> months;
@@ -1595,6 +1708,7 @@ class _FlowBars extends StatelessWidget {
     String? labelId,
     TxFlowFilter? flow,
   }) onMonthTap;
+  final VoidCallback onChartTap;
 
   @override
   Widget build(BuildContext context) {
@@ -1613,7 +1727,10 @@ class _FlowBars extends StatelessWidget {
     });
 
     if (empty) {
-      return Center(
+      return GestureDetector(
+        behavior: HitTestBehavior.opaque,
+        onTap: onChartTap,
+        child: Center(
           child: Text(
             period == OverviewPeriodMode.yearly
                 ? 'No income or expenses in these years'
@@ -1621,6 +1738,7 @@ class _FlowBars extends StatelessWidget {
             style: theme.textTheme.bodyMedium,
             textAlign: TextAlign.center,
           ),
+        ),
       );
     }
 
@@ -1632,15 +1750,25 @@ class _FlowBars extends StatelessWidget {
           touchCallback: (event, response) {
             if (event is! FlTapUpEvent) return;
             final spot = response?.spot;
-            if (spot == null) return;
-            final index = spot.touchedBarGroupIndex;
-            if (index < 0 || index >= months.length) return;
+            final index = spot?.touchedBarGroupIndex;
+            if (spot == null ||
+                index == null ||
+                index < 0 ||
+                index >= months.length) {
+              // Parent GestureDetector also handles empty-area taps.
+              return;
+            }
             final rodIndex = spot.touchedRodDataIndex;
             // Rods: 0 = expense, 1 = income.
             final flow = rodIndex == 1
                 ? TxFlowFilter.income
                 : TxFlowFilter.expense;
+            final scope = _ChartTapScope.maybeOf(context);
+            if (scope != null) {
+              scope.openBar(() => onMonthTap(months[index], flow: flow));
+            } else {
               onMonthTap(months[index], flow: flow);
+            }
           },
           touchTooltipData: BarTouchTooltipData(
             getTooltipItem: (group, groupIndex, rod, rodIndex) {
@@ -1755,6 +1883,7 @@ class _LabelMonthBars extends StatelessWidget {
     required this.barStyle,
     required this.invertChart,
     required this.onMonthTap,
+    required this.onChartTap,
   });
 
   static const _maxSeriesLabels = 6;
@@ -1771,6 +1900,7 @@ class _LabelMonthBars extends StatelessWidget {
     String? labelId,
     TxFlowFilter? flow,
   }) onMonthTap;
+  final VoidCallback onChartTap;
 
   double _plot(double value) => invertChart ? -value : value;
 
@@ -1779,12 +1909,16 @@ class _LabelMonthBars extends StatelessWidget {
     final theme = Theme.of(context);
     final colors = theme.colorScheme;
     if (labelSpend.isEmpty) {
-      return Center(
+      return GestureDetector(
+        behavior: HitTestBehavior.opaque,
+        onTap: onChartTap,
+        child: Center(
           child: Text(
             'No labeled activity in this period.\nTag transactions to see them here.',
             style: theme.textTheme.bodyMedium,
             textAlign: TextAlign.center,
           ),
+        ),
       );
     }
 
@@ -1841,12 +1975,16 @@ class _LabelMonthBars extends StatelessWidget {
       }
     }
     if (maxY == 0 && minY == 0) {
-      return Center(
+      return GestureDetector(
+        behavior: HitTestBehavior.opaque,
+        onTap: onChartTap,
+        child: Center(
           child: Text(
             'No labeled activity in this period.\nTag transactions to see them here.',
             style: theme.textTheme.bodyMedium,
             textAlign: TextAlign.center,
           ),
+        ),
       );
     }
     final span = (maxY - minY).abs();
@@ -1949,9 +2087,14 @@ class _LabelMonthBars extends StatelessWidget {
           touchCallback: (event, response) {
             if (event is! FlTapUpEvent) return;
             final spot = response?.spot;
-            if (spot == null) return;
-            final index = spot.touchedBarGroupIndex;
-            if (index < 0 || index >= months.length) return;
+            final index = spot?.touchedBarGroupIndex;
+            if (spot == null ||
+                index == null ||
+                index < 0 ||
+                index >= months.length) {
+              // Parent GestureDetector also handles empty-area taps.
+              return;
+            }
             String? labelId;
             if (stacked) {
               final stackIdx = spot.touchedStackItemIndex;
@@ -1965,7 +2108,14 @@ class _LabelMonthBars extends StatelessWidget {
               }
             // Last rod may be "Other" — open month with chart labels only.
             }
+            final scope = _ChartTapScope.maybeOf(context);
+            if (scope != null) {
+              scope.openBar(
+                () => onMonthTap(months[index], labelId: labelId),
+              );
+            } else {
               onMonthTap(months[index], labelId: labelId);
+            }
           },
           touchTooltipData: BarTouchTooltipData(
             getTooltipItem: (group, groupIndex, rod, rodIndex) {