fix: Shift+Click on column header now triggers multi-column sort

CHANGELOG.md

@@ -40,6 +40,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - PostgreSQL: Schema name lost after app restart, causing "relation does not exist" errors for non-public schemas
 - Error dialog OK button not dismissing when a SwiftUI sheet is active, making the app unusable
+- Shift+Click on column header not triggering multi-column sort (NSTableView swallows Shift+Click on headers)
 - SQL Server: Unicode characters (Thai, CJK, etc.) in nvarchar/nchar/ntext columns displaying as question marks
 - Globe+F (fn+F) fullscreen shortcut not working in SwiftUI lifecycle app
 

TablePro/Views/Results/DataGridCoordinator.swift

@@ -32,6 +32,7 @@ final class TableViewCoordinator: NSObject, NSTableViewDelegate, NSTableViewData
     var onHideColumn: ((String) -> Void)?
     var onMoveRow: ((Int, Int) -> Void)?
     var onNavigateFK: ((String, ForeignKeyInfo) -> Void)?
+    var sortState = SortState()
     var getVisualState: ((Int) -> RowVisualState)?
     var dropdownColumns: Set<Int>?
     var typePickerColumns: Set<Int>?

TablePro/Views/Results/DataGridView.swift

@@ -83,6 +83,9 @@ struct DataGridView: NSViewRepresentable {
 
         let tableView = KeyHandlingTableView()
         tableView.coordinator = context.coordinator
+        let sortableHeader = SortableTableHeaderView()
+        sortableHeader.coordinator = context.coordinator
+        tableView.headerView = sortableHeader
         tableView.style = .plain
         tableView.setAccessibilityLabel(String(localized: "Data grid"))
         tableView.setAccessibilityRole(.table)
@@ -176,6 +179,7 @@ struct DataGridView: NSViewRepresentable {
 
         scrollView.documentView = tableView
         context.coordinator.tableView = tableView
+        context.coordinator.sortState = sortState
         context.coordinator.onMoveRow = onMoveRow
         context.coordinator.rebuildColumnMetadataCache()
         if let connectionId {
@@ -229,6 +233,7 @@ struct DataGridView: NSViewRepresentable {
         )
         if currentIdentity == coordinator.lastIdentity {
             // Only refresh closure callbacks — they capture new state on each body eval
+            coordinator.sortState = sortState
             coordinator.onCellEdit = onCellEdit
             coordinator.onSort = onSort
             coordinator.onAddRow = onAddRow
@@ -299,6 +304,7 @@ struct DataGridView: NSViewRepresentable {
         coordinator.onRefresh = onRefresh
         coordinator.onCellEdit = onCellEdit
         coordinator.onDeleteRows = onDeleteRows
+        coordinator.sortState = sortState
         coordinator.onSort = onSort
         coordinator.onAddRow = onAddRow
         coordinator.onUndoInsert = onUndoInsert
@@ -504,7 +510,6 @@ struct DataGridView: NSViewRepresentable {
         }
     }
 
-    /// Synchronize sort descriptors and indicators with the table view
     private func syncSortDescriptors(tableView: NSTableView, coordinator: TableViewCoordinator) {
         coordinator.isSyncingSortDescriptors = true
         defer { coordinator.isSyncingSortDescriptors = false }
@@ -513,18 +518,16 @@ struct DataGridView: NSViewRepresentable {
             if !tableView.sortDescriptors.isEmpty {
                 tableView.sortDescriptors = []
             }
-        } else if let firstSort = sortState.columns.first,
-                  firstSort.columnIndex >= 0 && firstSort.columnIndex < rowProvider.columns.count {
-            // Sync with first sort column for NSTableView's built-in sort indicators
-            let key = "col_\(firstSort.columnIndex)"
-            let ascending = firstSort.direction == .ascending
-            let currentDescriptor = tableView.sortDescriptors.first
-            if currentDescriptor?.key != key || currentDescriptor?.ascending != ascending {
-                tableView.sortDescriptors = [NSSortDescriptor(key: key, ascending: ascending)]
+        } else {
+            let descriptors = sortState.columns.compactMap { sortCol -> NSSortDescriptor? in
+                guard sortCol.columnIndex >= 0 && sortCol.columnIndex < rowProvider.columns.count else { return nil }
+                return NSSortDescriptor(key: "col_\(sortCol.columnIndex)", ascending: sortCol.direction == .ascending)
+            }
+            if tableView.sortDescriptors != descriptors {
+                tableView.sortDescriptors = descriptors
             }
         }
 
-        // Update column header titles for multi-sort indicators
         Self.updateSortIndicators(tableView: tableView, sortState: sortState, columns: rowProvider.columns)
     }
 
@@ -662,19 +665,17 @@ struct DataGridView: NSViewRepresentable {
             guard let colIndex = Int(idString.dropFirst(4)),
                   colIndex < columns.count else { continue }
 
-            let baseName = columns[colIndex]
-
-            if let sortIndex = sortState.columns.firstIndex(where: { $0.columnIndex == colIndex }) {
-                let sortCol = sortState.columns[sortIndex]
-                if sortState.columns.count > 1 {
-                    let indicator = " \(sortIndex + 1)\(sortCol.direction.indicator)"
-                    column.title = "\(baseName)\(indicator)"
-                } else {
-                    // Single sort: NSTableView shows its own indicator, keep base name
-                    column.title = baseName
-                }
+            if let sortCol = sortState.columns.first(where: { $0.columnIndex == colIndex }) {
+                let imageName = sortCol.direction == .ascending
+                    ? "NSAscendingSortIndicator"
+                    : "NSDescendingSortIndicator"
+                tableView.setIndicatorImage(NSImage(named: imageName), in: column)
             } else {
-                // Not sorted: restore base name
+                tableView.setIndicatorImage(nil, in: column)
+            }
+
+            let baseName = columns[colIndex]
+            if column.title != baseName {
                 column.title = baseName
             }
         }

TablePro/Views/Results/Extensions/DataGridView+Sort.swift

@@ -24,6 +24,14 @@ extension TableViewCoordinator {
         onSort?(columnIndex, sortDescriptor.ascending, isMultiSort)
     }
 
+    // NSTableView swallows Shift+Click on headers, so SortableTableHeaderView calls this directly.
+    // Cycles: not sorted -> ascending -> descending -> remove
+    func handleShiftClickSort(columnIndex: Int) {
+        guard columnIndex >= 0 && columnIndex < rowProvider.columns.count else { return }
+        let ascending = !sortState.columns.contains(where: { $0.columnIndex == columnIndex })
+        onSort?(columnIndex, ascending, true)
+    }
+
     // MARK: - Double-Click Column Divider Auto-Fit
 
     func tableView(_ tableView: NSTableView, sizeToFitWidthOfColumn columnIndex: Int) -> CGFloat {

TablePro/Views/Results/KeyHandlingTableView.swift

@@ -422,3 +422,37 @@ final class KeyHandlingTableView: NSTableView {
         return super.menu(for: event)
     }
 }
+
+// MARK: - Sortable Table Header View
+
+/// Custom NSTableHeaderView that intercepts Shift+Click for multi-column sort.
+/// NSTableView swallows Shift+Click on column headers (sortDescriptorsDidChange never fires),
+/// so we detect the modifier here and route to the coordinator's multi-sort handler.
+final class SortableTableHeaderView: NSTableHeaderView {
+    weak var coordinator: TableViewCoordinator?
+
+    override func mouseDown(with event: NSEvent) {
+        guard event.modifierFlags.contains(.shift) else {
+            super.mouseDown(with: event)
+            return
+        }
+
+        // Shift is held — handle multi-sort manually
+        let pointInHeader = convert(event.locationInWindow, from: nil)
+        let clickedColumn = column(at: pointInHeader)
+        guard clickedColumn >= 0,
+              let tableView,
+              clickedColumn < tableView.tableColumns.count else {
+            super.mouseDown(with: event)
+            return
+        }
+
+        let column = tableView.tableColumns[clickedColumn]
+        guard let dataColumnIndex = DataGridView.columnIndex(from: column.identifier) else {
+            super.mouseDown(with: event)
+            return
+        }
+
+        coordinator?.handleShiftClickSort(columnIndex: dataColumnIndex)
+    }
+}