block_editor 0.0.4-dev.1

A Notion-inspired, block-based rich text editor for Flutter. Built from scratch with a plugin system, inline embeds, variables, tags, and export to JSON, Markdown, and HTML.

Changelog

All notable changes to the block_editor package are documented here.

The format follows Keep a Changelog. This package adheres to Semantic Versioning.

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0.0.4-dev.1 — 2026-04-02

Re-release of Phase 4 content with updated package README and fully working example app. No API changes from 0.0.3-dev.1.

Changed

• Package README.md rewritten with full public API documentation, usage examples, and roadmap
• Example app completed — demonstrates all built-in block types, formatting toolbar, slash command menu, block action menu, keyboard shortcuts, drag and drop, and read-only viewer mode

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0.0.3-dev.1 — 2026-04-01

Phase 4 — Toolbar & Commands. 540 tests passing. API is unstable — breaking changes are expected before 1.0.0.

Added

Keyboard Shortcuts

• KeyboardShortcutHandler — centralised keyboard shortcut dispatcher, fully testable without the Flutter binding
• ModifierKeys — value object carrying cmd, shift, alt booleans; production callers use ModifierKeys.fromHardware(), test callers construct directly
• KeyboardShortcutHandler.handle(KeyEvent, ModifierKeys) — dispatches a key event and returns whether it was consumed

Formatting Toolbar

• FormattingToolbar — context-sensitive floating toolbar appearing over any expanded text selection; never shown in readOnly mode
• Eight buttons: Bold, Italic, Underline, Strikethrough, Inline Code, Link, Text Color, Background Color
• Each button reflects active / inactive / mixed state across the selection with toggle semantics
• Display mode controlled by BlockEditorWidget.toolbarBreakpoint — floats above selection anchor above threshold, pins to editor bottom below it
• Color buttons delegate to onColorPickerRequested callback when provided, otherwise open built-in 12-swatch palette popover

Slash Command Menu

• SlashCommandMenu — data-driven block insertion menu triggered by / at the start of an empty block or after a space; never shown in readOnly mode
• Groups entries by BlockPlugin.slashCommandGroup() — built-in order: Text, Headings, Lists, Media, Embeds, Advanced; external groups follow alphabetically
• Real-time filtering as the user types; arrow key navigation; Enter or Tab confirms; Escape or Backspace-to-empty dismisses; mouse click selects
• On confirmation: empty triggering block is transformed to selected type; block with content gets a new block inserted below; / and filter text removed

Block Action Menu

• BlockActionMenu — five-action floating menu anchored to each block's drag handle; never shown in readOnly mode
• Actions: Delete Block, Duplicate Block, Turn Into (submenu), Move Up, Move Down
• Move Up disabled for first block; Move Down disabled for last block; all actions dispatch through BlockController

BlockEditorWidget — new parameters

• toolbarBreakpoint (double, default 768.0) — width threshold in logical pixels controlling toolbar display mode
• onColorPickerRequested (Future<Color?> Function(Color? currentColor)?) — optional custom color picker callback; built-in 12-swatch palette used when null

BlockRegistry

• plugins getter — returns all registered BlockPlugin instances; used by SlashCommandMenu and BlockActionMenu

BlockController

• duplicate(String blockId) — inserts a copy of the identified block immediately below it with a fresh UUID, preserving type, attributes, children, and delta

EditorEditingOperations — new methods

• applyStrikethrough() — toggles strikethrough on expanded selection or stores as pending attribute on collapsed selection
• applyInlineCode() — toggles inline code on expanded selection or stores as pending attribute on collapsed selection
• applyAttributes(InlineAttributes) — applies arbitrary InlineAttributes to the expanded selection; used by toolbar for color application
• extendSelectionToLineStart(), extendSelectionToLineEnd() — extend selection focus to start or end of current block
• extendSelectionToDocumentStart(), extendSelectionToDocumentEnd() — extend selection focus to first or last offset in document
• extendSelectionWordLeft(), extendSelectionWordRight() — extend selection focus one word boundary, crossing block boundaries
• applyBold(), applyItalic(), applyUnderline() — now also store pending attributes on collapsed selection, applied to next inserted character

Changed

• TextDelta.applyAttributes — toggle semantics added for boolean attributes (bold, italic, underline, strikethrough, inlineCode); if every op in the target range already has the attribute set it is removed, otherwise set on all ops; color and link attributes unaffected

Fixed

• Background color (InlineAttributes.backgroundColor) was stored correctly but never rendered; RichTextRenderer now reads and applies it alongside inline code background, with inline code taking priority
• InlineAttributes.copyWith silently ignored null values causing toggle-off to never work; TextDelta.applyAttributes now constructs InlineAttributes(...) directly so null correctly clears a field

Breaking Changes

• EditorEditingOperations is no longer const-constructible — it holds mutable pending attribute state; all construction sites use EditorEditingOperations(controller) without const so no call site changes are required for existing consumers

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0.0.2-dev.1 — 2026-03-20

First published pre-release. Covers Phase 1 (Document Model), Phase 2 (Rendering Engine), and Phase 3 (Block Plugin System). API is unstable — breaking changes are expected in future pre-release versions before 1.0.0.

Added

Document Model (Phase 1)

• BlockNode — typed content node with id, type, attributes, and children
• BlockDocument — root container with ordered BlockNode list, JSON serialisation and deserialisation
• TextDelta — inline rich text model as a list of DeltaOp objects
• DeltaOp sealed class with TextOp subtype carrying InlineAttributes
• InlineAttributes — bold, italic, underline, strikethrough, inline code, link, text color, background color
• BlockController — document state manager with insert, delete, update, move, and transform operations
• BlockTypes — typed constants for all built-in block type identifiers
• EditorSelection — sealed class replacing BlockSelection for cursor and range selection
• Undo/redo stack with snapshot-based history
• selectionStream on BlockController alongside the document change stream

Rendering Engine (Phase 2)

• BlockRenderer — stateless widget mapping BlockNode to its Flutter widget via BlockRegistry
• BlockEditorWidget — root editor widget with external BlockController ownership, keyboard events, focus, and scroll
• RichTextRenderer — converts TextDelta into a TextSpan tree
• Block widgets for Paragraph, H1, H2, H3, BulletList, NumberedList, Todo, Quote, and Divider
• Cursor rendering with public animation API
• Single-block and cross-block selection highlight
• Character-level editing operations in pure Dart
• Drag and drop block reordering with ghost preview and drop indicator
• readOnly flag on BlockEditorWidget
• BlockEvent sealed class as the universal block interaction contract
• CustomBlockEvent wrapper subtype for external package event extensibility

Block Plugin System (Phase 3)

• BlockPlugin abstract interface — blockType, build(), serialize(), deserialize(), optional toolbarButton(), slashCommandItem(), slashCommandGroup()
• BlockRegistry with public register(BlockPlugin) method — built-in blocks pre-registered internally
• Per-block stream system via BlockController.streamForBlock(String blockId)
• EditorEditingOperations extended to operate on TextDelta.ops preserving inline formatting
• IME and mobile soft keyboard input via TextInputConnection
• Built-in media block plugins: Image, Video, YouTube embed, File attachment, Code, Callout, Link
• Inline embed DeltaOp subtypes for variables and tags

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0.0.1 — 2026-01-01

Initial mono-repo scaffold. No functional code. Repository structure, CI pipeline, Melos workspace configuration, and pubspec files only.