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Unity Engine

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Script Reference

Unity Engine

BindableElement

UnityEngine.UIElements.BindableElement
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BindableElement is the base class for all elements that you can bind to a data source. It provides the following properties:
  • bindingPath
    : The path to the data source property to bind to.
  • binding
    : The binding object that represents the binding between the element and the data source.

Create a BindableElement

You can create a BindableElement with UXML or C#. The following C# example creates a BindableElement:
var bindableElement = new BindableElement();

C# base class and namespace

C# class: 
BindableElement
Namespace: 
UnityEngine.UIElements
Base class: 
VisualElement

Member UXML attributes

This element has the following member attributes:

Name

Type

Description

binding-path
string
Path of the target property to be bound.

Inherited UXML attributes

This element inherits the following attributes from its base class:

Name

Type

Description

focusable
boolean
Whether an element can potentially receive focus.

If false, the element can't receive focus. If true, the element receives focus only when its 
Focusable.canGrabFocus
property is also true.
tabindex
int
An integer used to sort focusable elements in the focus ring. Must be greater than or equal to zero.

Setting the 
tabIndex
value to less than 
0
(for example, 
−1
) removes the element from the focus ring and tab navigation.
This element also inherits the following attributes from 
VisualElement
:

Name

Type

Description

content-container
string
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 
VisualElement.Children
of an element, the element's content container hierarchy is used instead of the element itself. This can lead to unexpected results, such as elements being ignored by the navigation events if they are not directly in the content container's hierarchy. Refer to 
IFocusRing
for more information.

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 
ScrollView
, for example, has a content container that is different from itself. In that case, child elements added to the scroll view are added to its content container element instead. While the physical parent (
VisualElement.Hierarchy.parent
) of the child elements is the scroll view's content container element, their logical parent (
VisualElement.parent
) still refers to the scroll view itself. Since some of the scroll view's focusable children are not part of its logical hierarchy, like its 
Scroller
elements, these focusable children are not considered by default when using sequential navigation. Refer to How can I change what element is focused next for an example of a workaround solution if the default navigation rules don't correspond to your needs.
data-source
Object
Assigns a data source to this VisualElement which overrides any inherited data source. This data source is inherited by all children.
data-source-path
string
Path from the data source to the value.
data-source-type
System.Type
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.
enabled
boolean
Returns true if the 
VisualElement
is enabled locally.

This flag isn't changed if the VisualElement is disabled implicitly by one of its parents. To verify this, use 
enabledInHierarchy
.
language-direction
UIElements.LanguageDirection
Indicates the directionality of the element's text. The value will propagate to the element's children.
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
UIElements.PickingMode
Determines if this element can be the target of pointer events or picked by 
IPanel.Pick
queries.

Elements can not be picked if:

- They are invisible- Their 
style.display
is set to 
DisplayStyle.None


Elements with a picking mode of 
PickingMode.Ignore
never receive the hover pseudo-state.
style
string
Sets the style values on a 
VisualElement
.

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 
resolvedStyle
.



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.
tooltip
string
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.
usage-hints
UIElements.UsageHints
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).
view-data-key
string
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 
VisualElement
. For more information, refer to View data persistence in the Unity Manual.

USS classes

The following table lists all the C# public property names and their related USS selector.

C# property

USS selector

Description

disabledUssClassName
.unity-disabled
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 
VisualElement
at every level of its hierarchy.

Additional resources