lazy_wrap 1.1.1

A Flutter widget that mimics Wrap layout behavior with lazy rendering and zero layout jumps.

1.1.1

Added

• Added rapid-scroll regression coverage for measurement progress, edge bouncing, fade re-entry, row-spacing gaps, and large scroll offsets.
• Added an extreme validation scenario with 200,000 variable-size items, complete last-to-first traversal, and repeated edge jumps.
• Rebuilt the example as an interactive fixed/dynamic test lab with presets up to 200,000 items and manual rapid-scroll controls.

Changed

• Dynamic mode now uses exact precomputed row geometry instead of estimated variable-row offsets, making large jumps and rapid reversals deterministic.
• Row offsets and extents now use 64-bit precision for very large scroll areas.
• Internal benchmarks, planning documents, development tests, and experimental spike sources are excluded from the pub.dev archive.
• Refreshed the README around the public fixed and dynamic APIs.

Fixed

• Prevented dynamic Offstage measurement from stalling when consecutive sub-batches contain items with identical sizes.
• Added strict measurement backpressure so rapid edge scrolling cannot enqueue multiple unmeasured load batches and starve the UI thread.
• Removed the artificial load delay and made static custom loading indicators advance the measurement pipeline without requiring additional user input.
• Made one-time fade-ins resilient to row recycling and skipped transparent transitions during high-velocity scrolling, preventing gray/blank flashes.
• Kept loading state consistent when itemCount shrinks during pending work.
• Prevented following slivers from painting inside runSpacing gaps.

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1.1.0

Added

• Public engine enum: LazyWrapEngine { offstageV1, sliverV2 }.
• engine parameter in LazyWrap.dynamic and DynamicLazyWrap.
• itemWidthBuilder and itemHeightBuilder for sliverV2 opt-in.
• Engine parity tests and benchmark runner integration for sliverV2.

Changed

• DynamicLazyWrap now routes internally by engine while preserving the existing default behavior (offstageV1).
• Benchmark scenario dynamic_card_50k_sliver_v2 now uses the public API path (LazyWrap.dynamic(engine: LazyWrapEngine.sliverV2)).
• Offstage V1 visible widget cache now uses area-gated defaults tuned for large-card scenarios (OFFSTAGE_VISIBLE_WIDGET_CACHE_CAPACITY=256, OFFSTAGE_ADAPTIVE_VISIBLE_WIDGET_CACHE=true, OFFSTAGE_VISIBLE_WIDGET_CACHE_MIN_ITEM_AREA=12000).
• Added adaptive offstage measurement batch policy as opt-in experimental path (OFFSTAGE_ADAPTIVE_MEASURE_BATCH, OFFSTAGE_LARGE_ITEM_MEASURE_BATCH_CAP); default remains disabled to preserve current behavior.

Fixed

• Cleared stale measurement queues/state when itemCount shrinks in dynamic mode, preventing out-of-range item builds during pending measurement.

Notes

• sliverV2 is experimental and opt-in.
• Default engine remains offstageV1 (no breaking change).
• sliverV3 work remains internal/deep exploration and is not part of the public release surface in 1.1.0.

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1.0.0

🚀 Major Release - Zero Layout Jumps

• Offstage measurement: Items are now measured invisibly before display
• Zero layout jumps: No more "5 items → 10 items" sudden changes
• Fade-in animation: Optional smooth appearance (fadeInItems: true)
• Simplified API: Removed estimatedItemMainSize (no longer needed)
• Updated SDK: Requires Flutter 3.38+ and Dart 3.10+

Breaking Changes

• Removed estimatedItemMainSize and estimatedItemCrossSize params
• Removed animateRows, cleanupOffscreenSizes, memoryBufferMultiplier params

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0.1.1

• Bug fixed.

0.1.0

• Update documentation.

0.0.9+3

• Update screenshot.

0.0.9+2

• Update screenshot.

0.0.9+1

• Update screenshot.

0.0.9

• Added horizontal scroll.

0.0.8+6

• Added constructors.

0.0.8+5

• Update dynamic lazy wrap.

0.0.8+4

• Update default values.

0.0.8+3

• Added live demo.

0.0.8+2

• Bug fixed.

0.0.8+1

Fixed

• Fixed row alignment issue that caused overflow when using MainAxisAlignment.center.
• Wrapped Row in SizedBox with calculated width to prevent layout overflow.

0.0.8

• Added rowAlignment to allow horizontal alignment of children inside each row (e.g. center).

0.0.7

• Added fixed mode

0.0.6

• Performance improve

0.0.5

• Bug fixed.

0.0.4

• Bug fixed.

0.0.3

• Bug fixed.

0.0.2

• Added rowAlignment to allow horizontal alignment of children inside each row (e.g. center).

0.0.1

• Initial release.