Mastering Unity Custom Toolbar with VisualElement: Create Your Ultimate Developer Tool

Unity’s Custom Toolbar capabilities using VisualElement can revolutionize your workflow, especially for game developers looking to streamline repetitive tasks, integrate debugging tools, or enhance project organization. While Unity’s IMGUI has traditionally been the go-to solution for custom editor development, UI Toolkit with VisualElement offers a more modern, flexible, and visually appealing alternative.

In this article, we’ll explore how to create a robust custom toolbar in Unity using VisualElement, and why this approach is essential for professional game development. Whether you’re a seasoned programmer or just getting into Unity editor extensions, this guide will help you build a feature-rich, reusable toolbar.

Why Build a Custom Toolbar with VisualElement?

1. Increased Productivity
   Automate mundane tasks like scene loading, object management, or asset navigation.
2. Modern UI
   VisualElement provides a responsive, scalable UI that adapts to various resolutions and editor themes.
3. Customizability
   Add buttons, sliders, dropdown menus, and other interactive elements to suit your specific needs.
4. Reusable Code
   With proper modular design, the toolbar can be adapted for different projects, saving development time.

What is VisualElement?

VisualElement is part of Unity’s UI Toolkit, a system for creating user interfaces using a declarative, CSS-like approach. It replaces IMGUI and introduces better styling, event handling, and performance optimization.

Key features include:

• UXML: A markup language for defining UI layouts.
• USS: A style sheet language for controlling the appearance of elements.
• Hierarchy-based Layouts: Organize UI elements in a tree-like structure.

Where Can It Be Used?

Custom toolbars can be used in numerous scenarios:

• Level Designers: Quickly place prefabs or navigate scenes.
• Game Testing: Toggle debugging options, activate cheats, or track performance stats.
• Asset Management: Search and organize project assets efficiently.
• Pipeline Integration: Create buttons for common build or deployment tasks.

Step-by-Step: Building a Custom Toolbar

1. Setting Up Your Project

Ensure your project uses Unity 2021.1 or later, where UI Toolkit and VisualElement are fully supported. Add the UI Toolkit package via the Package Manager if not already included.

2. Creating the Toolbar Script

Toolbar Code (CustomToolbar.cs):

using UnityEditor;
using UnityEngine;
using UnityEngine.UIElements;

public class CustomToolbar : EditorWindow
{
    [MenuItem("Tools/Custom Toolbar")]
    public static void ShowToolbar()
    {
        var window = GetWindow<CustomToolbar>();
        window.titleContent = new GUIContent("Custom Toolbar");
        window.Show();
    }

    public void CreateGUI()
    {
        // Root container
        VisualElement root = rootVisualElement;

        // Style sheet
        var styleSheet = AssetDatabase.LoadAssetAtPath<StyleSheet>("Assets/Editor/CustomToolbar.uss");
        root.styleSheets.Add(styleSheet);

        // Add buttons
        var buttonContainer = new VisualElement { name = "button-container" };
        root.Add(buttonContainer);

        // Example buttons
        var loadSceneButton = new Button(() => LoadScene("SampleScene")) { text = "Load Scene" };
        var debugToggleButton = new Button(() => ToggleDebugMode()) { text = "Toggle Debug" };

        buttonContainer.Add(loadSceneButton);
        buttonContainer.Add(debugToggleButton);
    }

    private void LoadScene(string sceneName)
    {
        Debug.Log($"Loading Scene: {sceneName}");
        EditorApplication.OpenScene($"Assets/Scenes/{sceneName}.unity");
    }

    private void ToggleDebugMode()
    {
        Debug.Log("Debug Mode Toggled");
    }
}

3. Adding Styles

Style Sheet (CustomToolbar.uss):

#button-container {
    flex-direction: row;
    justify-content: space-around;
    margin: 10px;
}

button {
    font-size: 14px;
    background-color: #5A9;
    border-radius: 5px;
    padding: 5px;
    color: white;
}

4. Using UXML for Layouts (Optional)

If your toolbar requires a complex layout, define it in a UXML file.

UXML (CustomToolbar.uxml):

<ui:UXML xmlns:ui="UnityEngine.UIElements">
    <ui:VisualElement name="button-container">
        <ui:Button text="Load Scene" />
        <ui:Button text="Toggle Debug" />
    </ui:VisualElement>
</ui:UXML>

5. Testing and Enhancing

• Test the Toolbar: Open it via the Unity menu (Tools > Custom Toolbar).
• Enhance with Features: Add sliders, dropdown menus, or even live performance graphs.

Advantages and Disadvantages

Advantages

1. Enhanced Workflow: Streamlines repetitive tasks, saving time.
2. Reusable Codebase: Modular design allows the toolbar to be easily integrated into multiple projects.
3. Visually Appealing: UI Toolkit offers polished and modern interfaces.

Disadvantages

1. Learning Curve: Requires familiarity with VisualElement, USS, and UXML.
2. Compatibility: Limited to Unity 2021.1 and newer versions.

Conclusion

Building a custom toolbar in Unity with VisualElement is a powerful way to improve productivity and create professional-grade tools for your development pipeline. The example provided here demonstrates how to set up a basic toolbar, but the possibilities are endless—think dynamic asset previews, real-time debugging panels, or integrated build management.

With proper implementation, your custom toolbar will not only save time but also elevate the quality of your game development workflow. Start building your own now and redefine how you work in Unity!