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Angular Transfer List (Select + Move Between Two Lists)

By FrontendAtlas Team · Updated Jan 30, 2026

Build a dual-list transfer UI in Angular. Users select items in one list and move them to the other via buttons. Preserve order, clear selection after transfer, disable buttons when nothing is selected, and keep the UI consistent. Consider edge cases like large lists and…

Render two lists: Top and Bottom.
Each list renders items with a checkbox for selection.

What you’ll build / What this tests

This premium angular coding focuses on Angular Transfer List (Select + Move Between Two Lists). You’ll apply components and state thinking with medium level constraints. The prompt emphasizes Build a dual-list transfer UI in Angular. Users select items in one list and move them….

Learning goals

Translate the prompt into a clear angular API signature and return shape.
Apply components, state, forms techniques to implement angular transfer list (select + move between two lists).
Handle medium edge cases without sacrificing readability.
Reason about time/space complexity and trade-offs in angular.

Key decisions to discuss

Define the exact input/output contract before coding.
Choose iteration vs higher-order methods for readability.
Decide on concurrency and error propagation behavior.
Prioritize predictable edge-case handling over micro-optimizations.

Evaluation rubric

Correctness: covers required behaviors and edge cases.
Clarity: readable structure and predictable control flow.
Complexity: avoids unnecessary work for large inputs.
API discipline: no mutation of inputs; returns expected shape.
Testability: solution is easy to unit test.

Constraints / Requirements

Render two lists: Top and Bottom.
Each list renders items with a checkbox for selection.
Provide two transfer buttons between lists: "↓" moves selected Top items to Bottom; "↑" moves selected Bottom items…
Disable "↓" when no Top items are selected; disable "↑" when no Bottom items are selected.
After transfer, moved items must be unselected in the destination list.
Preserve item order within each list (append moved items to the end of destination list).
Selecting items in Top and clicking "↓" removes them from Top and appends them to Bottom.
Selecting items in Bottom and clicking "↑" removes them from Bottom and appends them to Top.
If nothing is selected in a list, its transfer button is disabled and does nothing.
Selections are independent per list and are cleared for moved items after transfer.

Mini snippet (usage only)

// Example usage
const input = /* angular transfer list (select + move between two lists) input */;
const result = solve(input);
console.log(result);

// Edge case check
const empty = input ?? null;
const fallback = solve(input);
console.log(fallback);

// Expected: describe output shape, not the implementation
// (no solution code in preview)

Common pitfalls

Mutating inputs instead of returning a new value.
Skipping edge cases like empty input, duplicates, or nulls.
Overlooking time complexity for large inputs.