changeTheme method
Updates the user's intent. Pass ThemeMode.system to follow the OS theme — currentMode then resolves to light / dark based on the platform brightness and re-resolves automatically when the OS theme is toggled.
Example:
themeService.changeTheme(ThemeMode.system);
Implementation
void changeTheme(ThemeMode requestedMode) {
runInAction(() => mode.value = requestedMode);
}