Selection State Pattern
Make selected rows, cards, and objects look and behave the same everywhere.
What it adds
One selection model and one visual treatment shared by tables, card grids, lists, and canvas surfaces.
What your agent is told to do
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What your agent is told to do
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Find every surface that already has a notion of selection — table rows, card grids, file lists, canvas objects, option pickers — and reduce them to a single selection model rather than the several that have accumulated.
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Hold selection as state keyed by stable record identity, never by row index or position in the DOM, so sorting, filtering, and paging cannot move the highlight onto a different record.
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Support click to select, modifier click to add and remove, and shift click to extend a range, and make each of those reachable from the keyboard as well as the pointer.
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Always show how many items are selected and give a single control that clears the selection, placed where the user can find it without scrolling back to the top of a long list.
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Do not express selection with a background tint alone. A row can be hovered, focused, and selected at once, and one tint cannot carry three meanings — pair selection with a persistent marker such as a checkbox or a border, and leave the focus ring itself to the Hover Active Focus Checklist.
Edge cases it handles
7
Edge cases it handles
7- Hover, keyboard focus, and selection frequently land on the same row at the same time; all three must stay readable together and none may visually cancel another.
- Range selection needs a defined anchor. The anchor must move on a plain click and be preserved across a shift click, or extending a range a second time selects the wrong span.
- Forced-colours and high contrast modes discard background colours, so selection must also be carried by a border, an outline, or a control that genuinely exists in the accessibility tree.
- Re-sorting, filtering, or paging must keep the same records selected, including records that have scrolled out of view, rather than keeping the same positions selected.
- Select-all needs a stated scope: everything on this page, or everything matching the current filter. Conflating the two ends with a bulk action applied to records the user never saw.
- A selected record deleted by someone else, or moved out of the filter, must drop out of the selection quietly and the count must update.
- Screen readers need the selected state exposed through the control's role rather than implied by colour; a selected row that reads identically to an unselected one is unusable.
Definition of done
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Definition of done
9- A single selection model backs tables, grids, lists, and canvas surfaces.
- Selection is keyed to record identity and survives sorting, filtering, and paging.
- Single, additive, and range selection all work with the pointer and from the keyboard.
- Hover, focus, and selected states remain distinguishable when applied to the same element.
- Selection stays visible under forced-colours and high contrast settings.
- The selected count is visible and can be cleared in one action.
- Select-all states its scope explicitly before it is applied.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Feedback Widget
Feedback Widget
Let anyone report a bug or send a comment from the page they are looking at.
What it does
An always-available launcher that opens a short feedback form and submits it with page context attached.
How it works
- 1 Put a single persistent launcher in one corner of the app and open a compact form in place. Do not route the user to a separate feedback page and lose the context they were about to describe.
- 2 Attach the current URL, the app version, the viewport size, the signed-in account, and a short trail of recent client errors automatically, so the reporter does not have to describe where they were.
- 3 Show the captured context to the user before they send it, in a collapsible section, and let them remove it. Silent collection of screen state is a trust problem.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/feedback-widget
Booking Page
Booking Page
A shareable page where someone picks an open time and confirms it in a few clicks.
What it does
A public scheduling page listing open slots, taking a booking, and confirming it to both sides.
How it works
- 1 Build the visitor path first: pick a date, see open times in their own zone, fill a short form, confirm, and receive an email with the details and a cancellation link. That is the minimum coherent version.
- 2 Derive open slots from the owner's availability rules and existing bookings on the server at request time. Do not trust a slot list the browser has been holding since page load.
- 3 Reuse the app's existing Time Zone-Aware Scheduling for conversion and storage, store every time as an absolute instant, and display it converted to the visitor's detected zone with the zone named on screen.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/booking-page
Date and Time Display Component
Date and Time Display Component
Render every date and time through one component so none of them are ambiguous.
What it does
A single shared way of displaying dates and times, covering absolute format, time zone, and optional relative phrasing.
How it works
- 1 Find every place the app renders a date or a time — tables, activity feeds, audit logs, exports, emails, tooltips — and route them all through one display path rather than formatting at each call site.
- 2 Never render an all-numeric date whose day and month could be swapped. Spell or abbreviate the month, or use an unambiguous ordering consistently, because a reader has no way to tell 04/07 from 07/04.
- 3 State the time zone whenever the value is a specific moment rather than a calendar day, and be explicit about whose zone it is — the viewer's, the record's, or the account's — rather than leaving it implied.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/date-and-time-display-component
How it works
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1
Copy the link
Grab the Markdown instruction URL for this feature.
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Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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It inspects, then implements
Your agent reads your existing app first, then adds the feature to fit it.
Works with your stack
These instructions are written to adapt. They tell the agent to detect your framework, match your existing design system, and reuse what you already have — rather than assuming a particular stack.
Need it tighter than that? Customize the feature and tell it exactly what you're running.