101 posts
An element removed by an if is gone immediately, so an exit animation has nothing to animate. AnimatedVisibility keeps it composed until the exit finishes — and AnimatedContent does the same for swaps.
updateTransition coordinates several animations driven by one state. It handles multi-state enums, per-property specs via transitionSpec, and child transitions — all with coherent interruption a group of animate*AsState calls cannot give you.
animate*AsState animates toward a target that can change at any moment. Understanding it as declarative rather than imperative explains interruption, redirection, and why spring is the right default.
The Compose animation surface looks large because it is organised by what you're animating rather than by how. Three questions pick the right API, and picking wrong is why animation code gets complicated.
A bitmap costs width × height × 4 bytes in memory regardless of its file size. Decoding at display size, choosing the right config and budgeting the cache are what keep an image-heavy app from being reclaimed.
Drawing custom shapes means Path plus DrawScope. Shadows are separate, and Modifier.shadow takes its own shape parameter — omitting it is why rounded cards get square shadows.
Compose gradients take pixel coordinates, so a hardcoded end point produces a different result on every screen size. Float.POSITIVE_INFINITY and DrawScope.size are the two ways to make a brush relative.
Painter draws content and declares an intrinsic size, which is what lets it participate in layout the way a resource does. Writing one is the right answer when drawing needs to be reusable across Image, Icon and modifiers.
ImageVector is drawing commands executed at render time; ImageBitmap is pixels held in memory. The choice is about scaling fidelity versus per-frame cost, and the common mistakes run in both directions.
Image sizing depends on the modifier constraints and contentScale together. Understanding which one crops, which one fits, and where the aspect ratio comes from resolves most image layout bugs in one pass.
Compose's autofill is a semantics property on a text field. Declaring content types lets password managers and the platform fill forms correctly, and omitting it is why users abandon sign-up.
A custom font covers a subset of Unicode. Everything outside it falls back, and the fallback decides how your app renders emoji, non-Latin scripts and symbols — usually without anyone checking.
