C# class: Foldout
Namespace: UnityEngine.UIElements
Base class: BindableElement
The following table lists all the supported attributes.
| 名前 | 型 | 説明 |
|---|---|---|
binding-path |
string |
Path of the target property to be bound. |
content-container |
string |
This element contains the elements that are shown or hidden when you toggle the Foldout. |
focusable |
boolean |
True if the element can be focused. |
name |
string |
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. |
picking-mode |
string |
Determines if this element can be pick during mouseEvents or IPanel.Pick queries. |
style |
string |
Reference to the style object of this element. Contains data computed from USS files or inline styles written to this object in C#. |
tabindex |
int |
An integer used to sort focusables in the focus ring. Must be greater than or equal to zero. |
text |
string |
This is the text of the toggle’s label. |
tooltip |
string |
Text to display inside an information box after the user hovers the element for a small amount of time. |
usage-hints |
string |
A combination of hint values that specify high-level intended usage patterns for the VisualElement.This property can only be set when the VisualElement is not yet part of a Panel. Once part of a Panel, this property becomes effectively read-only, and attempts to change it will throw an exception.The specification of proper UsageHints drives the system to make better decisions on how to process or accelerate certain operations based on the anticipated usage pattern.Note that those hints do not affect behavioral or visual results, but only affect the overall performance of the panel and the elements within. It’s advised to always consider specifying the proper UsageHints, but keep in mind that some UsageHints might be internally ignored under certain conditions (e.g. due to hardware limitations on the target platform). |
value |
boolean |
This is the state of the Foldout’s toggle. It is true if the Foldout is open and its contents arevisible, and false if the Foldout is closed, and its contents are hidden. |
view-data-key |
string |
Used for view data persistence (ie. tree expanded states, scroll position, zoom level). This is the key used to save/load the view data from the view data store. Not setting this key will disable persistence for this VisualElement. |
A Foldout has the following elements:
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>
You can bind a Foldout to a Boolean variable or access its value through the INotifyValueChanged<bool> interface.
A Foldout and its Toggle sub-element respond to Change events. The Toggle hides or shows the Foldout container.
To see which USS selectors affect the components of the Foldout at every level of its hierarchy, use the Matching Selectors section in the Inspector or the UI Toolkit Debugger.
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 container
var 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");
}
});