How Common UI is Setup in LyraStarterGame

This document describes how the CommonUI plugin is set up and used by LyraStarterGame.

For general information about CommonUI, see my Common UI Overview.

Overall UI Layout

• Project Settings
• Default UI Policy

UI Layers (Activatable Widget Stacks)

UI.Layer.Game

• Things like the HUD.
• Layer Root is expected to be assigned by the Lyra Experience
  • Layer Root generally derives from LyraHUDLayout

Example: W_ShooterHUDLayout

• Load B_ShooterGame_Elimination Experience
  • Activate LAS_ShooterGame_StandardHUD Action Set
    • Assign UI.Layer.Game = W_ShooterHUDLayout
    • Assign other widgets to slots defined by this HUD

UI.Layer.GameMenu

• “Menus” specifically related to gameplay, like maybe an in game inventory UI.
  • Not in use in current shipping version of Lyra
    • Prototype Inventory map incorrectly tries to use this, but it doesn’t work correctly.
• You can implement this yourself in your game
  • Make sure you make the root a LyraHUDLayout widget
    • Then add other widgets to the root as needed for your game

UI.Layer.Menu

• Things like the settings screen.
• Widgets get pushed to this layer by the UI.Layer.Game base class LyraHUDLayout

UI.Layer.Modal

• Confirmation dialogs, error dialogs.
• Managed by Lyra UI Messaging Subsystem

Lyra HUD Layout

LyraHUDLayout : public LyraActivatableWidget from CommonUI

/**
 * ULyraHUDLayout
 *
 *	Widget used to lay out the player's HUD (typically specified by an Add Widgets action in the experience)
 */
UCLASS(Abstract, BlueprintType, Blueprintable, Meta = (DisplayName = "Lyra HUD Layout", Category = "Lyra|HUD"))
class ULyraHUDLayout : public ULyraActivatableWidget

Widgets deriving from LyraHUDLayout will get native support to listen for UI.Action.Escape input tags and on each event push the BP-defined EscapeMenuClass to UI.Layer.Menu

The UI.Action.Escape event is defined in Project Settings

Debugging

When you’re wondering which widgets are currently active, you can use this console command to get an output log dump from Common UI:

Console Debug command: CommonUI.DumpActivatableTree