Optimize selective export implementation for performance and maintain…

lib/models/section.dart

@@ -92,6 +92,9 @@ class Section {
   bool getIsSelected() => isSelected;
   void setIsSelected(bool selected) => isSelected = selected;
 
+  /// Toggle selection state
+  void toggleSelection() => isSelected = !isSelected;
+
   double getLength() => length;
   double getDepthStart() => depthStart;
   double getDepthEnd() => depthEnd;

lib/models/section_list.dart

@@ -43,14 +43,35 @@ class SectionList {
   /// Get only selected sections
   List<Section> get selectedSections => sections.where((section) => section.isSelected).toList();
 
+  /// Get selection statistics in a single pass for better performance
+  SelectionStats get selectionStats {
+    if (sections.isEmpty) return SelectionStats.empty();
+
+    int selectedCount = 0;
+    for (final section in sections) {
+      if (section.isSelected) selectedCount++;
+    }
+
+    return SelectionStats(
+      total: sections.length,
+      selected: selectedCount,
+    );
+  }
+
   /// Check if all sections are selected
-  bool get allSelected => sections.isNotEmpty && sections.every((section) => section.isSelected);
+  bool get allSelected {
+    final stats = selectionStats;
+    return stats.total > 0 && stats.selected == stats.total;
+  }
 
   /// Check if no sections are selected
-  bool get noneSelected => sections.every((section) => !section.isSelected);
+  bool get noneSelected => selectionStats.selected == 0;
 
   /// Check if some sections are selected (for partial selection state)
-  bool get someSelected => sections.any((section) => section.isSelected) && !allSelected;
+  bool get someSelected {
+    final stats = selectionStats;
+    return stats.selected > 0 && stats.selected < stats.total;
+  }
 
   /// Select all sections
   void selectAll() {
@@ -66,16 +87,47 @@ class SectionList {
     }
   }
 
-  /// Toggle selection for all sections
+  /// Toggle selection for all sections (optimized)
   void toggleSelectAll() {
-    if (allSelected) {
-      deselectAll();
-    } else {
-      selectAll();
+    final shouldSelectAll = selectionStats.selected < sections.length;
+    for (final section in sections) {
+      section.isSelected = shouldSelectAll;
+    }
+  }
+
+  /// Set selection state for multiple sections efficiently
+  void setSelectionForSections(List<Section> sectionsToUpdate, bool selected) {
+    for (final section in sectionsToUpdate) {
+      section.isSelected = selected;
     }
   }
 
   /// Legacy getters/setters for compatibility with existing code
   List<Section> getSections() => sections;
   void setSections(List<Section> newSections) => sections = newSections;
+}
+
+/// Efficient statistics for section selection state
+class SelectionStats {
+  final int total;
+  final int selected;
+
+  const SelectionStats({required this.total, required this.selected});
+
+  const SelectionStats.empty() : total = 0, selected = 0;
+
+  /// Get number of unselected sections
+  int get unselected => total - selected;
+
+  /// Check if all are selected
+  bool get allSelected => total > 0 && selected == total;
+
+  /// Check if none are selected
+  bool get noneSelected => selected == 0;
+
+  /// Check if some are selected
+  bool get someSelected => selected > 0 && selected < total;
+
+  @override
+  String toString() => 'SelectionStats(selected: $selected, total: $total)';
 }

lib/widgets/data_toolbar.dart

@@ -39,89 +39,115 @@ class DataToolbar extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return AppBar(
-      // Left side - Input functions
-      leading: Row(
-        mainAxisSize: MainAxisSize.min,
-        children: [
-          // Select all/deselect all button
-          if (hasSections)
-            IconButton(
-              onPressed: onToggleSelectAll,
-              icon: Icon(allSectionsSelected ? Icons.deselect : Icons.select_all),
-              tooltip: allSectionsSelected ? "Deselect All" : "Select All",
-            ),
-
-          // Clear data button
-          IconButton(
-            onPressed: !hasSections ? null : onReset,
-            icon: const Icon(Icons.backspace_rounded),
-            tooltip: "Clear local Data",
-          ),
-
-          // Read data from device button
-          IconButton(
-            onPressed: (serialBusy || !connected) ? null : onReadData,
-            icon: const Icon(Icons.download_rounded),
-            tooltip: "Read Data from Device",
-          ),
-
-          // Open DMP file button
-          FileIcon(
-            onPressed: serialBusy ? null : onOpenDMP,
-            icon: Icons.file_open,
-            extension: 'DMP',
-            tooltip: "Open DMP file",
-            size: 24,
-            color: serialBusy ? Colors.black26 : Colors.black54,
-            extensionColor: serialBusy ? Colors.black26 : Colors.black87,
-          ),
-        ],
-      ),
-      leadingWidth: hasSections ? 240 : 192, // Adjust width based on whether select all button is shown
-
-      // Right side - Export functions
-      actions: [
-        // Save DMP file button
-        FileIcon(
-          onPressed: (serialBusy || !hasSelectedSections) ? null : onSaveDMP,
-          extension: 'DMP',
-          tooltip: "Save selected surveys as DMP",
-          size: 24,
-          color: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black54,
-          extensionColor: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black87,
-        ),
-
-        // Export to Excel button
-        FileIcon(
-          onPressed: (serialBusy || !hasSelectedSections) ? null : onExportXLS,
-          extension: 'XLS',
-          tooltip: "Export selected surveys as Excel",
-          size: 24,
-          color: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black54,
-          extensionColor: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black87,
-        ),
-
-        // Export to Survex button
-        FileIcon(
-          onPressed: (serialBusy || !hasSelectedSections) ? null : onExportSVX,
-          extension: 'SVX',
-          tooltip: "Export selected surveys as Survex",
-          size: 24,
-          color: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black54,
-          extensionColor: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black87,
-        ),
-
-        // Export to Therion button
-        FileIcon(
-          onPressed: (serialBusy || !hasSelectedSections) ? null : onExportTH,
-          extension: 'TH',
-          tooltip: "Export selected surveys as Therion",
-          size: 24,
-          color: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black54,
-          extensionColor: (serialBusy || !hasSelectedSections) ? Colors.black26 : Colors.black87,
-        ),
-      ],
+      leading: _buildInputActions(),
+      leadingWidth: hasSections ? 240 : 192,
+      actions: _buildExportActions(),
       backgroundColor: Colors.white30,
     );
   }
+
+  Widget _buildInputActions() {
+    return Row(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        if (hasSections) _buildSelectAllButton(),
+        _buildClearDataButton(),
+        _buildReadDataButton(),
+        _buildOpenDMPButton(),
+      ],
+    );
+  }
+
+  Widget _buildSelectAllButton() {
+    return IconButton(
+      onPressed: onToggleSelectAll,
+      icon: Icon(allSectionsSelected ? Icons.deselect : Icons.select_all),
+      tooltip: allSectionsSelected ? "Deselect All" : "Select All",
+    );
+  }
+
+  Widget _buildClearDataButton() {
+    return IconButton(
+      onPressed: !hasSections ? null : onReset,
+      icon: const Icon(Icons.backspace_rounded),
+      tooltip: "Clear local Data",
+    );
+  }
+
+  Widget _buildReadDataButton() {
+    return IconButton(
+      onPressed: (serialBusy || !connected) ? null : onReadData,
+      icon: const Icon(Icons.download_rounded),
+      tooltip: "Read Data from Device",
+    );
+  }
+
+  Widget _buildOpenDMPButton() {
+    return FileIcon(
+      onPressed: serialBusy ? null : onOpenDMP,
+      icon: Icons.file_open,
+      extension: 'DMP',
+      tooltip: "Open DMP file",
+      size: 24,
+      color: serialBusy ? Colors.black26 : Colors.black54,
+      extensionColor: serialBusy ? Colors.black26 : Colors.black87,
+    );
+  }
+
+  List<Widget> _buildExportActions() {
+    return [
+      _buildSaveDMPButton(),
+      _buildExportExcelButton(),
+      _buildExportSurvexButton(),
+      _buildExportTherionButton(),
+    ];
+  }
+
+  Widget _buildSaveDMPButton() {
+    return _buildExportFileIcon(
+      onPressed: onSaveDMP,
+      extension: 'DMP',
+      tooltip: "Save selected surveys as DMP",
+    );
+  }
+
+  Widget _buildExportExcelButton() {
+    return _buildExportFileIcon(
+      onPressed: onExportXLS,
+      extension: 'XLS',
+      tooltip: "Export selected surveys as Excel",
+    );
+  }
+
+  Widget _buildExportSurvexButton() {
+    return _buildExportFileIcon(
+      onPressed: onExportSVX,
+      extension: 'SVX',
+      tooltip: "Export selected surveys as Survex",
+    );
+  }
+
+  Widget _buildExportTherionButton() {
+    return _buildExportFileIcon(
+      onPressed: onExportTH,
+      extension: 'TH',
+      tooltip: "Export selected surveys as Therion",
+    );
+  }
+
+  Widget _buildExportFileIcon({
+    required VoidCallback? onPressed,
+    required String extension,
+    required String tooltip,
+  }) {
+    final isEnabled = !serialBusy && hasSelectedSections;
+    return FileIcon(
+      onPressed: isEnabled ? onPressed : null,
+      extension: extension,
+      tooltip: tooltip,
+      size: 24,
+      color: isEnabled ? Colors.black54 : Colors.black26,
+      extensionColor: isEnabled ? Colors.black87 : Colors.black26,
+    );
+  }
 }