Struct ThemeOverrideWatcher 

pub struct ThemeOverrideWatcher { /* private fields */ }

Per-shell-instance watcher over the process-wide override slot: each of the three shells owns one, polling it once per frame (desktop: before rebuild in RedrawRequested; mobile: at the top of the frame callback) to detect a set_app_theme/clear_app_theme call since the last poll.

Implementations

impl ThemeOverrideWatcher

pub fn new() -> Self

A fresh watcher, matching the slot’s initial (never-overridden) state.

pub fn poll(&mut self) -> Option<Option<Theme>>

Poll the slot once. Returns:

• None — no set_app_theme/clear_app_theme call since the last poll (or since construction); the shell does nothing.
• Some(Some(theme)) — a new forced theme to push to both delivery paths.
• Some(None) — the override was cleared; the shell should revert to its platform-derived default theme.

Trait Implementations

impl Debug for ThemeOverrideWatcher

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ThemeOverrideWatcher

fn default() -> Self

Returns the “default value” for a type.