sheetifye 1.1.0

Flutter spreadsheet engine with XLSX/CSV support, live editing, undo/redo, formula evaluation, clipboard, autofill, and a full persistence lifecycle.

Changelog

All notable changes to Sheetifye are documented here. This project follows Semantic Versioning and Keep a Changelog.

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1.1.0 — 2026-05-18 🚀

This release transforms Sheetifye from a viewer into a full spreadsheet editing platform. Every major subsystem has been upgraded or built from scratch, with 324 tests covering the complete lifecycle.

✨ Added

Editing System

• Inline Cell Editor — Double-tap or keyboard entry opens a native text overlay directly over the active cell.
• Formula Entry — Type = to begin a formula; the formula bar shows the raw expression while the cell renders the computed result.
• readOnly Flag — Toggle the widget between view-only and fully editable modes at runtime.

Persistence Lifecycle

• onSave callback — Async hook invoked when the user triggers Save; return true to mark the workbook clean.
• onSaveAs callback — Async hook for Save As workflows.
• onBeforeClose callback — Intercepts back-navigation and window-close events; prompt users to save before exiting.
• onDiscardChanges callback — Hook for discard/revert flows.
• onWorkbookChanged callback — Fires whenever the workbook content or dirty state changes; ideal for driving save-indicator UI.
• PersistenceOptions — Internal provider that decouples lifecycle callbacks from the widget tree.
• Dirty State Tracking — WorkbookState.hasUnsavedChanges reflects whether there are uncommitted edits.

Undo / Redo

• Full undo/redo stack powered by a command pattern architecture.
• Undo/redo interactions correctly update the dirty state flag.
• Accessible via keyboard shortcuts (desktop) and the workbook action menu.

Clipboard System

• In-App Copy/Paste — Copies a cell range to an internal clipboard with formula reference shifting.
• System Clipboard — Falls back to RFC-4180 TSV parsing when pasting from external sources (Excel, Sheets).
• Formula Shifting — Relative formula references are automatically adjusted on paste.

Autofill Engine

• Drag the autofill handle to extend a cell's value or pattern to adjacent cells.
• Smart-fill detects arithmetic sequences and repeating text patterns.

Formula Engine Improvements

• AST-based tokenizer and evaluator for nested formula expressions.
• Live re-evaluation — changing a cell immediately recalculates all dependents.
• Dependency graph tracks cell relationships for targeted invalidation.

Workbook Action System

• WorkbookAction model — Describes any executable workbook-level action (id, label, icon, group, callbacks).
• WorkbookActionGroup enum — file, sharing, workbook, view, developer, other.
• customActions parameter — Inject developer-defined actions into the workbook menu from the host app.
• Adaptive menu — Renders as a bottom sheet on mobile and a popup menu on desktop/web.
• Built-in actions — Save, Save As, Export CSV, Export XLSX, Undo, Redo, Discard Changes.

Export API

• WorkbookExporter.toCsv(workbook) — Export any sheet to a CSV string.
• WorkbookExporter.toXlsxBytes(workbook) — Export the active sheet to a minimal XLSX byte array.
• WorkbookExporter.toJson(workbook) — Serialize the full workbook to JSON.

Overlay System

• Cell editor overlay renders above the grid canvas without disrupting scroll state.
• Autofill drag-handle overlay with gesture detection.
• OverlayManager coordinates all overlay layers cleanly.

Validation

• Cell validation rules enforceable at the engine level.
• Invalid entries are highlighted and blocked based on configured constraints.

Mobile UX

• Adaptive toolbar for touch devices: contextual bottom sheet replaces the desktop popup menu.
• Touch-optimized selection handles.
• Soft keyboard interaction managed transparently by the editor overlay.

🚀 Improved

• CSV Support — CSV parsing upgraded to RFC-4180 compliant scanner supporting quoted fields, escaped commas, and CRLF line endings.
• Sorting — Sort any column ascending/descending while maintaining row index integrity via rowIndexManager.
• Filtering — Column filters now track active state and can be cleared independently.
• Merged Cell Hit Testing — Accurate selection and editing within merged regions.
• Shimmer Loading — Refined shimmer animation during initial file parsing.
• Error Widget — Default error UI now shows a Retry button when file loading fails.
• Source cacheKey — Widget correctly reloads when the source changes without requiring a full rebuild.

🔧 Fixed

• Fixed use_build_context_synchronously — ScaffoldMessenger captured before await gaps in example app.
• Fixed implementation_imports — WorkbookAction is now exported from the public library barrel.
• Fixed curly_braces_in_flow_control_structures — All bare if statements in the clipboard manager now use blocks.
• Fixed merged cell scroll rendering artifacts on high-DPI displays.
• Fixed formula bar not updating when navigating between sheets.

⚡ Performance

• Background parsing via compute() isolates XLSX and CSV parsing from the UI thread.
• LRU cache bounds memory usage regardless of dataset size.
• Formula dependency graph ensures only affected cells re-evaluate on mutation.
• Undo/redo stack operations complete in <1 ms.

🧪 Testing

• 324 tests across 31+ test files — all passing.
• 17 engine test categories: clipboard, CSV, editing, filtering, formulas, interoperability, merged cells, overlays, persistence (12 files), recalculation, scrolling, selection, sorting, structure, undo/redo, validation, virtualization.
• 5 widget test categories: editor overlay, formula bar, grid, toolbar, workbook.
• 5 integration test categories: desktop, mobile, web, stress, XLSX samples.

⚠️ Breaking Changes

None. All new parameters (onSave, onSaveAs, onBeforeClose, onDiscardChanges, onWorkbookChanged, customActions) are optional and default to the original read-only viewer behavior. Existing integrations require no migration.

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1.0.2 — 2026-05-13

🚀 Improved

• SEO & Discoverability — Optimized all documentation for search engines and pub.dev rankings.
• Onboarding Experience — Restructured README with clear installation and usage guides.
• Example Gallery — Polished the example application and simplified the quick-start guide.

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1.0.1 — 2026-05-12

🔧 Fixed

• Fixed minor rendering artifacts in merged cell regions on specific screen densities.
• Improved memory cleanup when disposing of large workbooks.

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1.0.0 — 2026-05-12 🎉

✨ Added

• Virtualized Rendering Engine — High-performance grid maintaining 60+ FPS on workbooks of any size.
• Native XLSX Parsing — Full in-app Excel reader supporting assets, file, memory, and network sources.
• Bi-directional Scrolling — Smooth horizontal and vertical navigation.
• Selection System — Advanced single-cell and range selection with keyboard and touch support.
• Formula Bar — Professional UI for viewing raw cell values and computed results.
• Merged Cell Support — Accurate rendering and hit-testing for complex spreadsheet layouts.
• Custom Theming — Theme-aware UI that integrates seamlessly with your app's brand.

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