How-To: Live Preview, Confirmation & Restart

Goal: give the Apply/Cancel flow AAA behavior - preview changes before committing, keep/revert dialogs for risky settings, and a restart banner.

Prerequisites

A UCrimsonSettingScreen subclass (Quick Start step 4). All three are optional.

Live preview

With live preview on, slider/option changes update the UI immediately but do not commit until Apply; Cancel discards them. It works automatically for the _BP value classes (which the data asset creates).

Screenshot pendingImages/CrimsonSettings/howto-preview-toggle.png

WBP_SettingsScreen -> Details -> Settings -> tick Live Preview (or call Set Live Preview at runtime).

Confirmation countdown

Mark a risky setting (resolution, display mode) with Requires Confirmation (and optional Confirmation Timeout Seconds, default 15) in the data asset. On Apply the change goes live, then the screen fires K2_OnConfirmationRequired(TimeoutSeconds); call ConfirmSettingChange() on Keep or RevertSettingChange() on Revert / timeout.

Hook	When
`K2_OnConfirmationRequired(Timeout)`	Fired after Apply when a confirmation-required setting was applied - show the keep/revert countdown UI.
`ConfirmSettingChange()`	Player pressed Keep - locks in the value.
`RevertSettingChange()`	Player pressed Revert, or your timer expired - restores the previous value.

Restart required

Mark a setting Requires Restart in the data asset. When such a setting is applied, the screen fires K2_OnRestartRequired() - override it to show a restart banner.

Verify

Preview: changes revert on Cancel. Confirmation: a countdown appears after Apply and auto-reverts if you wait. Restart: the banner shows after applying a restart-flagged setting.

Apply / Cancel is built in

The screen's Apply/Cancel run through UCrimsonSettingRegistryChangeTracker: ApplyChanges() commits every dirty setting; the screen's CancelChanges() reverts them via the tracker's RestoreToInitial() on each dirty setting (discarding preview values).