Posts by Tech Android Network Team

Passing a value down through every view in a hierarchy, layer by layer, gets unwieldy fast when many unrelated views need the same piece of shared state — a logged-in…

SwiftUI decides whether to update an existing view or throw it away and create a fresh one based on a concept called identity. Misunderstanding it is behind a specific, recognizable…

NavigationStack, introduced in iOS 16, replaced the older NavigationView for pushing and popping screens. The main thing it adds is programmatic control: instead of only reacting to a user tapping…

State is the data that changes what your Compose UI looks like — a counter's value, whether a menu is open, the list of items fetched from a server. Getting…

State hoisting is the pattern Compose uses instead of two-way data binding: rather than a component owning and mutating its own state, you move ("hoist") that state up to a…

A composable function is supposed to be free of side effects — it just describes UI based on its inputs, and Compose may call it more often than you'd expect,…

mutableStateOf and MutableStateFlow both hold a value and notify observers when it changes, and both are common choices for state in a Compose app. They're not interchangeable, though — they…

derivedStateOf exists to solve a specific, easy-to-miss performance problem: recomputing a value from other state on every recomposition, even when that computed value hasn't actually changed. The Problem It Solves…

Unnecessary recomposition — Compose re-running a function whose output hasn't actually changed — is the most common source of jank in a Compose app. Here's how to actually see it…

Compose can skip recomposing a function entirely if it can prove none of its inputs actually changed. Whether it can prove that comes down to a concept called stability. Understanding…