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Get started with UI Toolkit

Follow a simple workflow to get started with UI Toolkit.
Read time 7 minutesLast updated a month ago

Want to create your first UI with UI Toolkit? Use this basic UI Toolkit workflow example to get started.
Note
For demonstration purposes, this guide describes how to add UI controls for the Editor UI. However, the instructions on adding UI controls to a UI Document also apply to runtime UI. For more information, refer to Get started with runtime UI.
If you perform a specific task often, you can use UI Toolkit to create a dedicated UI for it. For example, you can create a custom Editor window. The example demonstrates how to create a custom Editor window and add UI controls into your custom Editor window with UI Builder, UXML, and C# script.
You can find the completed files that this example creates in this GitHub repository.

Create a custom Editor window

Create a custom Editor window with two labels.
  1. Create a project in Unity Editor with any template.
  2. In the Project window, right-click in the
    Assets
    folder, and then select Create > UI Toolkit > Editor Window.
  3. In UI Toolkit Editor Window Creator, enter
    SimpleCustomEditor
    in the C# box.
  4. Keep the UXML checkbox selected and clear the USS checkbox.
  5. Select Confirm.
  6. To open the Editor window, select Window > UI Toolkit > SimpleCustomEditor.
You can find the source files for it in the
Assets/Editor
folder.

Add UI controls to the window

You can add UI controls to your window in the following ways:
You can use any of these methods individually, or combine. The following examples create three sets of labels, buttons, and toggles with a combination of these methods.

Use UI Builder to add UI controls

To visually add UI controls to your window, use UI Builder. The following steps add a button and a toggle into your custom Editor window in addition to the default label.
  1. In the
    Editor
    folder, double-click
    SimpleCustomEditor.uxml
    to open the UI Builder.
  2. In the UI Builder, drag Button and Toggle from Library > Controls into the Hierarchy or the window preview in the
    Viewport

    ?

    .
  3. In the Hierarchy window, select Label.
  4. In the
    Inspector

    ?

    window, change the default text to
    These controls were created in UI Builder
    in the Text field.
  5. In the Hierarchy window, select Button.
  6. In the Inspector window, enter
    This is button1
    in the Text field.
  7. Enter
    button1
    in the Name field.
  8. In the Hierarchy window, select Toggle.
  9. In the Inspector window, enter
    Number?
    in the Label field.
  10. Enter
    toggle1
    in the Name field.
  11. Save and close the UI Builder window.
  12. Close your custom Editor window if you haven't done so.
  13. In the Project window, select
    SimpleCustomEditor.cs
    and make sure the Visual Tree Asset is set to
    SimpleCustomEditor (Visual Tree Asset)
    in the Inspector window.
  14. Select Window > UI Toolkit > SimpleCustomEditor to re-open your custom Editor window to see the button and the toggle you just added.

Custom Editor Window with one set UI Controls

Use UXML to add UI controls

If you prefer to define your UI in a text file, you can edit the UXML to add the UI controls. The following steps add another set of label, button, and toggle into your window.
  1. In the
    Editor
    folder, select Assets > Create > UI Toolkit > UI Document to create a UXML file called
    SimpleCustomEditor_UXML.uxml
    .
  2. Select the arrow on
    SimpleCustomEditor_UXML.uxml
    in the Project window.
  3. Double-click
    inlineStyle
    to open
    SimpleCustomEditor_UXML.uxml
    in a text editor.
  4. Replace the contents of
    SimpleCustomEditor_uxml.uxml
    with the following:
    <ui:UXML xmlns:ui="UnityEngine.UIElements" xmlns:uie="UnityEditor.UIElements" xsi="http://www.w3.org/2001/XMLSchema-instance" engine="UnityEngine.UIElements" editor="UnityEditor.UIElements" noNamespaceSchemaLocation="../../UIElementsSchema/UIElements.xsd" editor-extension-mode="False"> <ui:Label text="These controls were created with UXML." /> <ui:Button text="This is button2" name="button2"/> <ui:Toggle label="Number?" name="toggle2"/></ui:UXML>
  5. Open
    SimpleCustomEditor.cs
    .
  6. Import the UXML file you created manually by adding the following to the
    CreateGUI
    method:
    // Import UXML created manually.var visualTree = AssetDatabase.LoadAssetAtPath<VisualTreeAsset>("Assets/Editor/SimpleCustomEditor_uxml.uxml");VisualElement labelFromUXML = visualTree.Instantiate();root.Add(labelFromUXML);
  7. Save your changes.
  8. Select Window > UI Toolkit > SimpleCustomEditor. This opens your custom Editor window with three labels, two buttons, and two toggles.

Custom Editor Window with two sets UI Controls

Use C# script to add UI controls

If you prefer coding, you can add UI Controls to your window with a C# script. The following steps add another set of label, button, and toggle into your window.
  1. Open
    SimpleCustomEditor.cs
    .
  2. Unity uses
    UnityEngine.UIElements
    for basic UI controls like label, button, and toggle. To work with UI controls, you must add the following declaration if it's not already present.
    using UnityEngine.UIElements;
  3. Change the text of the existing label from
    "Hello World! From C#"
    to
    "These controls were created using C# code."
    .
  4. The EditorWindow class has a property called
    rootVisualElement
    . To add the UI controls to your window, first instantiate the element class with some attributes, and then use the
    Add
    methods of the
    rootVisualElement
    .
    Your finished
    CreateGUI()
    method looks like the following:
    public void CreateGUI(){ // Each editor window contains a root VisualElement object VisualElement root = rootVisualElement; // VisualElements objects can contain other VisualElements following a tree hierarchy. Label label = new Label("These controls were created using C# code."); root.Add(label); Button button = new Button(); button.name = "button3"; button.text = "This is button3."; root.Add(button); Toggle toggle = new Toggle(); toggle.name = "toggle3"; toggle.label = "Number?"; root.Add(toggle); // Instantiate UXML created automatically which is set as the default VisualTreeAsset. root.Add(m_VisualTreeAsset.Instantiate()); // Import UXML created manually. var visualTree = AssetDatabase.LoadAssetAtPath<VisualTreeAsset>("Assets/Editor/SimpleCustomEditor_uxml.uxml"); VisualElement labelFromUXML = visualTree.Instantiate(); root.Add(labelFromUXML);}
  5. Select Window > UI Toolkit > SimpleCustomEditor to open your custom Editor window to see three labels, three buttons, and three toggles.

Custom Editor Window with three Controls

Define the behavior of your UI controls

You can set up event handlers for your UI controls so that when you click the button, and select or clear the toggle, your UI controls perform some tasks.
In this example, set up event handlers that:
  • When a button is clicked, the Editor Console displays a message.
  • When a toggle is selected, the Console shows how many times the buttons have been clicked.
Your finished
SimpleCustomEditor.cs
looks like the following:
using UnityEditor;using UnityEngine;using UnityEngine.UIElements;public class SimpleCustomEditor : EditorWindow{ [SerializeField] private VisualTreeAsset m_VisualTreeAsset = default; [MenuItem("Window/UI Toolkit/SimpleCustomEditor")] public static void ShowExample() { SimpleCustomEditor wnd = GetWindow<SimpleCustomEditor>(); wnd.titleContent = new GUIContent("SimpleCustomEditor"); } private int m_ClickCount = 0; private const string m_ButtonPrefix = "button"; public void CreateGUI() { // Each editor window contains a root VisualElement object VisualElement root = rootVisualElement; // VisualElements objects can contain other VisualElement following a tree hierarchy. Label label = new Label("These controls were created using C# code."); root.Add(label); Button button = new Button(); button.name = "button3"; button.text = "This is button3."; root.Add(button); Toggle toggle = new Toggle(); toggle.name = "toggle3"; toggle.label = "Number?"; root.Add(toggle); // Instantiate UXML created automatically which is set as the default VisualTreeAsset. root.Add(m_VisualTreeAsset.Instantiate()); // Import UXML created manually. var visualTree = AssetDatabase.LoadAssetAtPath<VisualTreeAsset>("Assets/Editor/SimpleCustomEditor_uxml.uxml"); VisualElement labelFromUXML = visualTree.Instantiate(); root.Add(labelFromUXML); //Call the event handler SetupButtonHandler(); } //Functions as the event handlers for your button click and number counts private void SetupButtonHandler() { VisualElement root = rootVisualElement; var buttons = root.Query<Button>(); buttons.ForEach(RegisterHandler); } private void RegisterHandler(Button button) { button.RegisterCallback<ClickEvent>(PrintClickMessage); } private void PrintClickMessage(ClickEvent evt) { VisualElement root = rootVisualElement; ++m_ClickCount; //Because of the names we gave the buttons and toggles, we can use the //button name to find the toggle name. Button button = evt.currentTarget as Button; string buttonNumber = button.name.Substring(m_ButtonPrefix.Length); string toggleName = "toggle" + buttonNumber; Toggle toggle = root.Q<Toggle>(toggleName); Debug.Log("Button was clicked!" + (toggle.value ? " Count: " + m_ClickCount : "")); }}

Test the example

  • From the menu, select Window > UI Toolkit > SimpleCustomEditor.

Additional resources