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SkillsMP has collected 224 skills from maxrave-dev/kotlin-footguns. Open a skill to review its source and details.
maxrave-dev/kotlin-footgunsShowing 40 of 224 collected skills.
The multiplatform resource formatter substitutes plain positional placeholders and nothing else — no flags, no width, no escaped percent — so padding, rounding, units and symbols belong in code and the resource only ever joins already-formatted pieces. Covers…
Reading a response whose shape drifts — classify each field by the marker the payload itself declares rather than by its position, treat a filtering map as data loss and count what it drops, refuse to substitute a placeholder for a failed parse, and parse…
A per-word karaoke wipe driven straight off a ticking time source looks stepped instead of smooth, a word that was already fully sung stays lit after the user seeks backward past it, or skinning an existing line-level lyrics renderer for word-level…
A design rule with legitimate exceptions survives only if every exception carries its reason at the call site and the rule itself is greppable — otherwise nothing distinguishes an exception from a violation and the rule silently rots. Covers where the rule…
A reusable top-glow layer that gives pages with no imagery of their own the same tinted ground the image-backed screens get — emitted as the first sibling of a navigation destination's content, with no wrapper, because destinations already stack. Covers why a…
Derive a complete tonal colour scheme from one artwork-extracted seed and wrap only that subtree in it, so every control inherits contrast-paired roles instead of hand-picked swatches — covers falling back by comparing against the sentinel the seed was…
Rules for implementing a protocol someone else defined — no renaming, no reordering, constants the schema omits read off the counterpart implementation rather than guessed, unknown message types decoded to null instead of thrown, and negotiated capabilities…
Group events by local hour or local day in application code from one raw scan, not in SQL — the engine's local-time modifier answers from the process time zone rather than the user's, and four local-time aggregates mean four scans that can disagree with each…
Keep a tracked markdown file of dated entries that record symptom, mechanism, what was ruled out and the condition for removing the workaround — and enforce it with a rule that the entry lands with the change. Use when a fix rests on non-obvious behaviour…
A custom window title bar, splash, or crash dialog composed as a sibling of the app theme rather than inside it reads MaterialTheme's framework DEFAULT scheme — light, always, no matter what the user picked — and nothing errors. Covers extracting the…
An editable value that is written on focus loss stores whatever was half-typed when a dialog, a rotation or a stray tap took the focus away; keep the draft in its own state keyed on the stored value and write only when the user asks for it. Covers why the…
Mine a repository's history without being misled by it — an empty-bodied commit's file statistics are its real abstract, a nested-repository bump hides its entire content behind a one-line pointer change, and a merge flattens a branch's decision trail into a…
A shared ViewModel base class for Compose Multiplatform — container-aware so subclasses can pull extra dependencies without constructor threading, with one loading/error surface for every screen — and the blocking resource-lookup hazard that such a base…
Size a slider's range from the real distribution of values it will be handed — stored, imported, migrated — rather than from a neighbouring control's range, because a value outside the range parks the thumb at the end of the track while your readout shows a…
A crossfade's container is a Box aligned to the top-start corner and sized to the largest child currently composed, so swapping a thin child for a taller one pins the thin one to the top mid-transition and drops it when the tall one leaves. Covers boxing both…
Render a change figure against an empty or zero baseline as nothing at all — never "+100%", never an infinity, never a saturated integer — and guard the two spans being compared as well as the divisor. Use when a new user's first period shows a huge increase…
Detect a scrub as a playhead that moved further than wall-clock time can account for, from the progress stream every platform already emits, because the platform's own discontinuity callback exists on one backend only and neither the item stream nor the…
Pass the raw target to a component that animates a property itself — an externally tweened value is a stream of new targets, and such components typically ignore new targets while their own animation is still running, which freezes the effect part-way. Covers…
Put several measures that share no whole onto concentric arcs instead of slicing one circle between them, cap the largest sweep short of 360°, and draw value wedges over a full-ring track. Use when a donut/pie is about to encode counts that do not add up to…
A celebration burst drawn by a plain draw modifier that paints past its host's own bounds — draw modifiers are unclipped by default, so the modifier must sit before every .clip(...) in the chain, and any clipping ancestor still trims whatever leaves its edge.…
When the value being edited is a curve, draw a draggable curve instead of N sliders and embed it in the settings list instead of pushing a screen — with a raw pointer loop rather than a drag-gesture helper, a draft that commits once per gesture, and smoothing…
Replace a populated header with an empty-state message without deleting the controls that header owned — re-supply them only in the branch that owned them, order the loading branch above the empty one, and stop reserving the artwork's height for a line of…
Split a span into buckets of exactly equal width and let the remainder fall outside, pick the bucket unit from how many rows a person will read, and never draw a partial newest bucket at full width. Use when a bar chart's oldest or newest bar is inexplicably…
Fire a one-shot celebration effect from the click that caused it, never from the state that click produced — an effect watching a boolean for a false→true edge cannot tell a tap from data arriving a beat later, so moving to an already-marked record fires the…
Expose a device capability to shared Compose code as a @Composable expect function, with a full implementation on the platform that has it and a stub that returns the neutral value on the platform that does not. Covers the three shapes these take — a…
Two independent features want entries in one engine property that holds the WHOLE chain, so writing it replaces everything — keep each feature's entries in its own field, compose them in a single writer, and let "clear" drop only its own tier. Use when a…
Counting entities encountered for the first time means taking MIN over the entity's whole history and asking whether that minimum lands inside the window — the natural version, which filters to the window and then groups, calls every entity new. Covers why…
When a user setting picks between two renderings of the same control — an expensive decorative one and a plain twin — every geometry decision has to be mirrored between them (item width, bar height, indicator size, inset, and the rule that computes the width…
Re-subscribe a downstream flow whenever a key flow changes using flatMapLatest, then collapse the resulting high-frequency stream to a composite key with distinctUntilChanged before firing expensive one-shot work. Use when a fetch re-runs on every progress…
A control floated over a scrolling column is a sibling that takes part in no measurement, so the column has to reserve the strip it covers explicitly — as a leading spacer, or as a header row whose twin spacers keep a centred title centred over the hole.…
Build a follower's playable item from the payload the shared session carries, not by re-resolving it from your own catalogue — a local resolver that infers the rendition from artwork shape lands on the wrong one, and a per-item network round trip inside the…
A follower in a shared session owns its own stop button — pausing is local and silent, and pressing play asks where the session is now rather than restoring where this device stopped. Use when a follower cannot pause because the next state update immediately…
Keep one part of a Compose app rendered dark — screens drawn over dark artwork — while the rest of the app follows the user's light theme, by providing a whole dark colour scheme plus your own token locals to that subtree; includes why a text-colour flag…
Put a user's on/off setting for an optional decorative surface treatment inside the one shared primitive that draws it — published from the theme as a CompositionLocal defaulting to on — instead of asking every call site to check the flag. Covers why the off…
Build a home-screen widget that renders the app's existing state holder rather than a parallel copy of it, by injecting the same shared state object and the same long-lived scope the app already uses and re-issuing the widget update whenever that state…
Share the boolean that drives a fade, never the tween that runs it — each look derives its own curve, so one can go asymmetric (fast in, slow out) without changing how the other feels; covers why a symmetric linear fade over a bright backdrop makes…
Bundle a multi-field setting into one immutable value and hand it to a hot consumer as a supplier, so the consumer asks "has this changed?" with a single reference comparison instead of diffing N numbers per buffer — and can never observe the fields…
Retry a record's image at a variant the source guarantees when the high-resolution one is missing, by holding the URL in composition state and swapping it once in onError. Covers making the disk-cache key follow the mutated URL, resetting the state per…
Specify a user-facing exchange file — why a version field can be worse than none, rejecting a file whose parse yields nothing, stating the same-length rule that positionally-aligned arrays imply, naming the legacy values a producer must never emit, and, when…
Pick one boundary convention for a stepping period navigator and hold it everywhere — a closed upper bound at 23:59:59 drops the last second's sub-second remainder, and half-open bounds handed to an inclusive BETWEEN double-count the shared instant — then…