Sentinal - Unity Menu Navigation & UI Selection System

A Unity package for managing hierarchical menu navigation with history tracking, input system integration, and automatic UI element selection. Perfect for game menus, settings panels, and any UI that requires structured navigation flow.

Note

This does not replace UGUI's navigation system.

🚀 Quick Start

1. Add the Core Manager: Place the SentinalManager singleton component in your scene.
2. Setup Menu Views: Add SentinalViewSelector components to your menu GameObjects.
3. Optional Input Integration: Add InputSystemHandler for automatic input management.
4. Optional Action Map Switching: Add InputActionSwitcher for seamless input context switching.

Tip

Use the provided Sentinal prefab from the Examples sample for quick setup.

Important

The SentinalManager component is required for this package to work. Navigation is triggered by GameObject activation/deactivation (OnEnable/OnDisable).

✨ Features

Core Navigation

• Menu/View Tracking: Navigate through multiple menus with automatic history tracking.
• UI Selection: Auto-selection of UI elements with memory of last selected items.
• Root View Support: Persistent root menus that stay in history but don't auto-close.
• Exclusive Views: Views that close all other menus when opened (excluding root views).

Input System Integration

• Action Map Switching: Automatic switching between Player/UI (or custom) action maps.
• Configurable Actions: Customizable input actions for different canceling and focus.

Developer Experience

• Custom Editor Tools: Runtime debugging with view stack visualization.
• Extensible Interfaces: ICloseableView and ISentinalSelector for custom behaviours.
• Comprehensive Events: Complete event system for view/menu operations.

📋 Requirements

• Unity 2019.4 or later
• Input System package (optional, for input handling features)
• TextMeshPro (for sample scenes)

🔧 Core Components

SentinalManager (Singleton Manager)

The central manager that handles all view/menu navigation logic and maintains the view stack.

Public API:

• CloseCurrentView() - Close the topmost view in the stack.
• CloseAllViews() - Close all views except root views.
• TrySelectCurrentView() - Attempt to select the current view's UI element.
• AnyViewsOpen - Check if any views are currently open.
• CurrentView - Get the currently active view selector.

Events:

• OnAdd - Fired when a new view is added to the stack.
• OnRemove - Fired when a view is removed from the stack.
• OnSwitch - Fired when switching between views.

SentinalViewSelector (Menu Component)

Add this to any GameObject that represents a menu or navigable view. One that will be SetActive(bool).

Properties:

• firstSelected - The GameObject to auto-select when this view becomes active.
• rootView - Treat as root view (added to history but never closed automatically).
• exclusiveView - Close all other views (except root views) when this view opens.
• trackView - Whether to include this view in the navigation history stack.
• preventSelection - Prevent automatic selection (useful for input-only views).
• autoSelectOnEnable - Automatically select the first element when view is enabled.
• rememberLastSelected - Remember and restore the last selected UI element.

InputSystemHandler (Optional Input Manager)

Handles Input System integration for input navigation.

Properties:

• playerInput - Reference to the PlayerInput component for input handling.
• cancelAction - Input action reference to close the current menu/view.
• focusAction - Input action reference to refocus the last selected element.

InputActionSwitcher (Auto Action Map Switching)

Automatically switches between action maps when menus open/close. Requires SentinalViewSelector component.

Properties:

• onEnableActionMapName - Action map name to switch to when this view opens (default: "UI").
• onAllDisableActionMapName - Action map name when all views are closed (default: "Player").
• rememberPreviousActionMap - Remember and restore previous action map instead of using onAllDisableActionMapName.
• logSwitching - Enable debug logging for action map switches.

🎯 Usage Examples

Basic Menu Setup

// Your menu GameObject needs:
// 1. SentinalViewSelector component
// 2. Enable/Disable the GameObject to open/close menus

// Open a menu
menuGameObject.SetActive(true); // Automatically tracked by SentinalManager

// Close current menu
SentinalManager.Instance.CloseCurrentView();

// Close all menus
SentinalManager.Instance.CloseAllViews();

Custom Closeable Menu With ICloseableView

[RequireComponent(typeof(SentinalViewSelector))]
public class CustomMenu : MonoBehaviour, ICloseableView
{
    [SerializeField] private Animator menuAnimator;

    public void Close()
    {
        // Custom close logic (animations, save data, etc.)
        StartCoroutine(CloseWithAnimation());
    }

    private IEnumerator CloseWithAnimation()
    {
        menuAnimator.SetTrigger("CloseMenu");
        yield return new WaitForSeconds(0.3f);
        gameObject.SetActive(false);
    }
}

Event Handling & Stack Monitoring

private void Start()
{
    SentinalManager.Instance.OnAdd += OnMenuOpened;
    SentinalManager.Instance.OnRemove += OnMenuClosed;
    SentinalManager.Instance.OnSwitch += OnMenuSwitched;
}

private void OnMenuOpened(SentinalViewSelector view)
{
    Debug.Log($"Menu opened: {view.name}");
    // Update UI, play sounds, etc.
}

private void OnMenuSwitched(SentinalViewSelector from, SentinalViewSelector to)
{
    Debug.Log($"Switched from {from?.name} to {to?.name}");
    // Handle transition effects
}

🐛 Debugging

Runtime Inspector

The custom editor shows real-time debugging information:

• Current view index in the navigation stack.
• Whether the view is currently active.
• View hierarchy visualization.

📝 Best Practices

1. Always use GameObject activation (SetActive(bool)) for menu open/close operations.
2. Use ICloseableView for menus that need custom close animations or specific menu closure.
3. Use Root Views for persistent UI elements like HUDs or a main menu screen.
4. Use Exclusive Views for modal dialogs or full-screen overlays.