Manager

The base class for all game system managers — automatic two-stage initialization and lifecycle integration with the Game Manager.
Categories:
Tags:

Image showing a Manager prefab with the wrapper entity set as Editor-Only inside Prefab Edit Mode.

Overview

The GS_ManagerComponent is the base class that all game system managers inherit from. It handles the two-stage initialization pattern with the Game Manager automatically, so you can focus on your system’s logic without worrying about startup ordering.

Every built-in GS_Play manager (Save, Stage, Options, UI, Unit, Camera, Audio, Performer) extends this class. When you need a custom game system manager, you extend it too.

How It Works

When the Game Manager spawns its list of manager prefabs, each Manager component goes through this lifecycle:

  1. Activate — The component initializes itself (connects to buses, sets up internal state). When done, it broadcasts OnRegisterManagerInit() to tell the Game Manager it is ready.

  2. OnStartupManagers — Called by the Game Manager after all managers have reported initialized. This is where you connect to other managers and set up cross-references. When done, broadcasts OnRegisterManagerStartup().

  3. OnStartupComplete — The Game Manager broadcasts this after all managers report started up. The game is fully ready.

  4. OnEnterStandby / OnExitStandby — Called when the Game Manager enters or exits standby mode. Pause and resume your subsystem here.

  5. OnShutdownManagers — Called when the game is shutting down. Clean up your subsystem.

The base class handles steps 1-2 automatically — you override them to add your own logic, then call the base implementation to complete the handshake.

Setup

Image showing the Manager wrapper entity set as Editor-Only inside Prefab Edit Mode.

  1. Create an entity. Attach your Manager component (built-in or custom) to it.
  2. Configure any properties needed in the Entity Inspector.
  3. Turn the entity into a prefab.
  4. Enter prefab edit mode. Set the wrapper entity (parent of your Manager entity) to Editor Only. Save.
  5. Delete the Manager entity from the level (it will be spawned by the Game Manager at runtime).
  6. In the Game Manager prefab, add your Manager .spawnable to the Startup Managers list.

The premade manager prefabs for each GS_Play gem are located in that gem’s Assets/Prefabs directory.

Inspector Properties

The base GS_ManagerComponent exposes no inspector properties of its own. Properties are defined by each inheriting manager component (e.g., the Save Manager exposes a Save System Version Number, the Stage Manager exposes a Stages list).

API Reference

Lifecycle Bus: GameManagerOutgoingEventBus

The Manager base class automatically subscribes to these events from the Game Manager:

EventWhen It FiresWhat You Do
OnStartupManagersAll managers are initializedConnect to other managers, set up cross-references, then call base to report.
OnStartupCompleteAll managers are started upBegin runtime operation.
OnEnterStandbyGame is entering standbyPause your subsystem (stop ticks, halt processing).
OnExitStandbyGame is exiting standbyResume your subsystem.
OnShutdownManagersGame is shutting downClean up resources, disconnect buses.

Registration Methods

These are called internally by the Manager base class to report back to the Game Manager:

MethodDescription
OnRegisterManagerInit()Called at the end of Activate(). Reports to the Game Manager that this manager has initialized.
OnRegisterManagerStartup()Called at the end of OnStartupManagers(). Reports to the Game Manager that this manager has started up.

Usage Examples

Checking if the Game Manager is Ready

#include <GS_Core/GS_CoreBus.h>

bool isStarted = false;
GS_Core::GameManagerIncomingEventBus::BroadcastResult(
    isStarted,
    &GS_Core::GameManagerIncomingEventBus::Events::IsStarted
);

if (isStarted)
{
    // Safe to access all managers
}

Extending the Manager Class

Create a custom manager whenever you need a singleton game system that initializes with the rest of the framework.

Header (.h)

#pragma once
#include <Source/Managers/GS_ManagerComponent.h>

// Define your EBus interface for other systems to call your manager
class MyManagerRequests
{
public:
    AZ_RTTI(MyManagerRequests, "{YOUR-UUID-HERE}");
    virtual ~MyManagerRequests() = default;

    virtual int GetSomeValue() = 0;
    virtual void DoSomething() = 0;
};

class MyManagerBusTraits : public AZ::EBusTraits
{
public:
    static constexpr AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Single;
    static constexpr AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::Single;
};

using MyManagerRequestBus = AZ::EBus<MyManagerRequests, MyManagerBusTraits>;

namespace MyProject
{
    class MyManagerComponent
        : public GS_Core::GS_ManagerComponent
        , protected MyManagerRequestBus::Handler
    {
    public:
        AZ_COMPONENT_DECL(MyManagerComponent);

        static void Reflect(AZ::ReflectContext* context);

    protected:
        // Manager lifecycle
        void Activate() override;
        void Deactivate() override;
        void OnStartupManagers() override;
        void OnEnterStandby() override;
        void OnExitStandby() override;

        // Your bus implementation
        int GetSomeValue() override;
        void DoSomething() override;

    private:
        int m_someValue = 0;
    };
}

Implementation (.cpp)

#include "MyManagerComponent.h"
#include <AzCore/Serialization/SerializeContext.h>

namespace MyProject
{
    AZ_COMPONENT_IMPL(MyManagerComponent, "MyManagerComponent", "{YOUR-UUID-HERE}");

    void MyManagerComponent::Reflect(AZ::ReflectContext* context)
    {
        if (auto serializeContext = azrtti_cast<AZ::SerializeContext*>(context))
        {
            serializeContext->Class<MyManagerComponent, GS_Core::GS_ManagerComponent>()
                ->Version(0)
                ->Field("SomeValue", &MyManagerComponent::m_someValue);

            if (AZ::EditContext* editContext = serializeContext->GetEditContext())
            {
                editContext->Class<MyManagerComponent>("My Manager", "A custom game system manager")
                    ->ClassElement(AZ::Edit::ClassElements::EditorData, "")
                        ->Attribute(AZ::Edit::Attributes::Category, "MyProject")
                        ->Attribute(AZ::Edit::Attributes::AppearsInAddComponentMenu, AZ_CRC_CE("Game"))
                    ->DataElement(AZ::Edit::UIHandlers::Default,
                        &MyManagerComponent::m_someValue, "Some Value", "Description of this property");
            }
        }
    }

    void MyManagerComponent::Activate()
    {
        // Connect your bus
        MyManagerRequestBus::Handler::BusConnect();

        // IMPORTANT: Call base Activate last — it reports OnRegisterManagerInit()
        GS_ManagerComponent::Activate();
    }

    void MyManagerComponent::Deactivate()
    {
        MyManagerRequestBus::Handler::BusDisconnect();
        GS_ManagerComponent::Deactivate();
    }

    void MyManagerComponent::OnStartupManagers()
    {
        // Access other managers here — they are all initialized by now
        // Example: query the Save Manager, connect to the Stage Manager, etc.

        // IMPORTANT: Call base last — it reports OnRegisterManagerStartup()
        GS_ManagerComponent::OnStartupManagers();
    }

    void MyManagerComponent::OnEnterStandby()
    {
        // Pause your subsystem
    }

    void MyManagerComponent::OnExitStandby()
    {
        // Resume your subsystem
    }

    int MyManagerComponent::GetSomeValue()
    {
        return m_someValue;
    }

    void MyManagerComponent::DoSomething()
    {
        // Your game system logic
    }
}

Module Registration

m_descriptors.insert(m_descriptors.end(), {
    MyProject::MyManagerComponent::CreateDescriptor(),
});

Then create a prefab for your manager and add it to the Game Manager’s Startup Managers list.

See Also