How-To: Show Save/Load Progress UI

Goal: show a loading screen while a slot loads, and a "saving - do not close the game" indicator while a save runs, both driven by the save manager's lifecycle delegates.

Prerequisites
You can reach the save manager from a widget or HUD (see How-To: Build a Save/Load Menu). All four delegates below live on UCrimsonSaveGameManagerSubsystem and are BlueprintAssignable.

1. The four lifecycle delegates

Each operation has a start/finish pair. Bind the start delegate to show UI and the matching finish delegate to hide it. Because saves and loads are asynchronous, never hide the UI on the line after the request call - wait for the finish delegate.

DelegateSignatureWhen fired
OnLoadStarted(none)A load begins, before any fragment is read.
OnLoadCompletebool bSuccessA load finishes. bSuccess is false if a fragment failed.
OnSaveStarted(none)A save begins, before any fragment is written.
OnSaveCompletebool bSuccessA save finishes. bSuccess is false if any fragment failed.

2. Bind start and finish to show and hide the UI

For the loading screen, add it to your loading queue on OnLoadStarted and remove it on OnLoadComplete. For the "do not quit" banner, show it on OnSaveStarted and hide it on OnSaveComplete. The save pair covers every save path - manual, quick, auto, and the synchronous save-on-exit.

Screenshot pendingImages/CrimsonSaveSystem/howto-progress-ui.png
On BeginPlay: **Get Crimson Save Game Manager** -> **Bind Event to On Load Started** (show loading screen) and **On Load Complete** (hide it), then **On Save Started** / **On Save Complete** for the saving banner.
Verify
Call RequestLoadFromSlot on a populated slot: the loading screen appears immediately and disappears only once OnLoadComplete fires. Then trigger a save and confirm the banner shows on OnSaveStarted and clears on OnSaveComplete.

3. Poll the state instead of binding

When you just need a yes/no right now - to gate a Quit button or a level-transition prompt - call IsSaveOrLoadInProgress() instead of holding your own flag. It is a BlueprintPure getter (Blueprint node Is Save Or Load In Progress) that returns true between any start and its matching complete.

cpp
UCrimsonSaveGameManagerSubsystem* SaveMgr =
    UCrimsonSaveGameManagerSubsystem::Get(this);


const bool bBusy = SaveMgr && SaveMgr->IsSaveOrLoadInProgress();
QuitButton->SetIsEnabled(!bBusy);
Multiplayer: where these fire
Saves are server/standalone only, so OnSaveStarted / OnSaveComplete fire only on the instance that runs the save - a listen-server host or a single-player client sees them; a pure client never does. To show a saving indicator on clients, replicate a flag or send a Client_ RPC from the server. Loads fire on whichever instance calls RequestLoadFromSlot.
Synchronous save-on-exit
SaveGameToActiveSlotSynchronous() (the shutdown / PIE-end save) blocks the game thread, so OnSaveStarted and OnSaveComplete fire back-to-back on the same frame. A banner will not paint during it - expected, since the game is closing.

See also

  • How-To: Handle Save/Load Errors
  • How-To: Build a Save/Load Menu
  • API Reference -> Save Manager Subsystem -> Delegates