Struct UidObserverCodes 

pub struct UidObserverCodes {
    pub register_code: u32,
    pub unregister_code: u32,
    pub register_for_uids_code: Option<u32>,
    pub on_gone_code: u32,
    pub on_active_code: u32,
    pub on_idle_code: u32,
    pub on_cached_code: u32,
    pub on_state_code: u32,
    pub on_adj_code: u32,
}

Uid lifecycle observer tx codes (uid-scoped, event-driven both ways).

registerUidObserver(observer, which, cutpoint, callingPackage) reports per-uid lifecycle events: onUidGone (no more processes for the uid), onUidActive (uid is no longer idle), onUidIdle, onUidCachedChanged (cached state changed), plus onUidStateChanged/onUidProcAdjChanged when the corresponding UID_OBSERVER_* flags are requested. The daemon pins the app’s uid at handoff, so it can filter these events on that single uid — no pid resolution, no /proc, no retry loop.

registerUidObserverForUids (added in S) is the filtered variant that only delivers events for a caller-supplied uid list; it requires the caller to hold PACKAGE_USAGE_STATS (or PERMISSION_GRANTED via root/system canAccessUnexportedComponents).

Fields

register_code: u32

TRANSACTION_registerUidObserver on IActivityManager$Stub

unregister_code: u32

TRANSACTION_unregisterUidObserver on IActivityManager$Stub

register_for_uids_code: Option<u32>

TRANSACTION_registerUidObserverForUids on IActivityManager$Stub (filtered variant, API 31+)

on_gone_code: u32

TRANSACTION_onUidGone on IUidObserver$Stub

on_active_code: u32

TRANSACTION_onUidActive on IUidObserver$Stub

on_idle_code: u32

TRANSACTION_onUidIdle on IUidObserver$Stub

on_cached_code: u32

TRANSACTION_onUidCachedChanged on IUidObserver$Stub

on_state_code: u32

TRANSACTION_onUidStateChanged on IUidObserver$Stub

on_adj_code: u32

TRANSACTION_onUidProcAdjChanged on IUidObserver$Stub