Foldout
UnityEngine.UIElements.Foldout
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A Foldout is a collapsible section of a UI. The Foldout hides or reveals the elements it contains when you click its header.
Foldout
Create a Foldout
A Foldout has the following elements:
- Label: A label you can use as the name of the Foldout.
- Toggle: Click the toggle to expand or collapse the container sub-element. It is styled to look like an arrow rather than the default checkbox. When the container is collapsed, the arrow points right. When the container is expanded, the arrow points down.
- Container: A container contains the visual elements that you want to show or hide when you toggle the Foldout.
You can add elements to a Foldout's container, and the show-or-hide function works automatically.
The following UI Document creates a Foldout with two buttons in its container. The two buttons show or hide when you toggle the Foldout.
<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:Foldout text="Foldout" name="MyFoldout" value="true"> <ui:Button text="First item" /> <ui:Button text="Second item" /> </ui:Foldout></ui:UXML>
Respond to user actions
A Foldout and its Toggle sub-element respond to Change events. The Toggle hides or shows the Foldout container.
You can bind a Foldout to a Boolean variable or access its value through the interface.
INotifyValueChanged<bool>Apply styles to the direct child of a Foldout
When you add elements to a Foldout, they're added under a child element of the Foldout that acts as a container. To add a style to this container, do this in USS:
/* Style only direct children of Foldout */Foldout > .unity-foldout__content { margin-left: 20px;}
Examples
The following C# code snippet creates a Foldout and checks whether the foldout is expanded:
// Create a new foldout, add two elements to it and add it to the containervar cSharpFoldout = new Foldout {text = "Elements"};cSharpFoldout.Add(new Label("Indented Label"));cSharpFoldout.Add(new Slider("Indented Slider", 0, 100));container.Add(cSharpFoldout);cSharpFoldout.RegisterValueChangedCallback(e =>{ // Check whether the foldout is expanded if (cSharpFoldout.value) { Debug.Log("Foldout is expanded"); } else { Debug.Log("Foldout is collapsed"); }});
C# base class and namespace
C# class:
FoldoutNamespace:
UnityEngine.UIElementsBase class:
BindableElementMember UXML attributes
This element has the following member attributes:
Name | Type | Description |
|---|---|---|
| | The label text for the toggle. |
| | Whether to toggle the foldout state when the user clicks the label. |
| | This is the state of the Foldout's toggle. It is true if the |
Inherited UXML attributes
This element inherits the following attributes from its base class:
Name | Type | Description |
|---|---|---|
| | Path of the target property to be bound. |
| | Whether an element can potentially receive focus. If false, the element can't receive focus. If true, the element receives focus only when its |
| | An integer used to sort focusable elements in the focus ring. Must be greater than or equal to zero. Setting the |
This element also inherits the following attributes from :
VisualElementName | Type | Description |
|---|---|---|
| | Logical container where child elements are added. If a child is added to this element, the child is added to this element's content container instead. When iterating over the If the content container is the same as the element itself, child elements are added directly to the element. This is true for most elements but can be overridden by more complex types. The |
| | Assigns a data source to this VisualElement which overrides any inherited data source. This data source is inherited by all children. |
| | Path from the data source to the value. |
| | The possible type of data source assignable to this VisualElement. This information is only used by the UI Builder as a hint to provide some completion to the data source path field when the effective data source cannot be specified at design time. |
| | Returns true if the This flag isn't changed if the VisualElement is disabled implicitly by one of its parents. To verify this, use |
| | Indicates the directionality of the element's text. The value will propagate to the element's children. |
| | The name of this VisualElement. Use this property to write USS selectors that target a specific element. The standard practice is to give an element a unique name. |
| | Determines if this element can be the target of pointer events or picked by Elements can not be picked if: - They are invisible- Their Elements with a picking mode of |
| | Sets the style values on a The returned style data, computed from USS files or inline styles written to this object in C#, doesn't represent the fully resolved styles, such as the final height and width of a VisualElement. To access these fully resolved styles, use For information about how to use this property and all the supported USS properties, refer to the Apply styles in C# scripts and USS properties reference manual pages. |
| | Text to display inside an information box after the user hovers the element for a small amount of time. This is only supported in the Editor UI. |
| | A combination of hint values that specify high-level intended usage patterns for the |
| | Used for view data persistence, such as tree expanded states, scroll position, or zoom level. This key is used to save and load the view data from the view data store. If you don't set this key, the persistence is disabled for the associated |
USS classes
The following table lists all the C# public property names and their related USS selector.
C# property | USS selector | Description |
|---|---|---|
| | The USS class name for Foldout elements. Unity adds this USS class to every instance of a |
| | The USS class name of Toggle sub-elements in Foldout elements. Unity adds this USS class to the |
| | The USS class name for the content element in a Foldout. Unity adds this USS class to the |
| | The USS class name for the Label element in a Foldout. Unity adds this USS class to the |
| | The USS class name for the Label element in a Foldout. Unity adds this USS class to the |
| | The USS class name for the Label element in a Foldout. Unity adds this USS class to the |
| | USS class name of local disabled elements. |
You can also use the Matching Selectors section in the Inspector or the UI Toolkit Debugger to see which USS selectors affect the components of the at every level of its hierarchy.
VisualElement