A RadioButton lets a user select a single choice when used along with other RadioButtons in a group. You can use a GroupBox to group RadioButtons. Otherwise, the panel acts as the default group.
A RadioButton responds to Change events.
You can bind a RadioButton to a Boolean variable or read its value when needed. Other radio buttons react when you change this variable.
The following C# code snippets add two new radio buttons to the same container and logically group them together in the panel.
var choice1 = new RadioButton() { text = "Choice 1" };
choice1.RegisterValueChangedCallback(v => Debug.Log("Choice 1 is : " + v.newValue));
var choice2 = new RadioButton() { text = "Choice 2" };
choice2.RegisterValueChangedCallback(v => Debug.Log("Choice 2 is : " + v.newValue));
container.Add(choice1);
container.Add(choice2);
The best way to learn how to use RadioButton is to try an example. To see a RadioButton example, in Unity, select Window > UI Toolkit > Samples > RadioButton.
C# class: RadioButton
Namespace: UnityEngine.UIElements
Base class: BaseBoolField
This element inherits the following attributes from its base class:
名称 | 类型 | 描述 |
---|---|---|
binding-path |
string |
Path of the target property to be bound. |
focusable |
boolean |
True if the element can be focused. |
label |
string |
The string representing the label that will appear beside the field. |
tabindex |
int |
An integer used to sort focusables in the focus ring. Must be greater than or equal to zero. |
text |
string |
Optional text that appears after the BaseBoolField. Unity creates a Label automatically if one does not exist. |
value |
boolean |
The value associated with the field. |
This element also inherits the following attributes from VisualElement
:
名称 | 类型 | 描述 |
---|---|---|
content-container |
string |
child elements are added to this element, usually this |
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 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#. |
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 (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 . |
The following table lists all the C# public property names and their related USS selector.
C# property | USS selector | 描述 |
---|---|---|
ussClassName |
.unity-radio-button |
USS class name for RadioButton elements. Unity adds this USS class to every instance of the RadioButton element. Any styling applied to this class affects every RadioButton located beside, or below the stylesheet in the visual tree. |
labelUssClassName |
.unity-radio-button__label |
USS class name for Labels in RadioButton elements. Unity adds this USS class to the Label sub-element of the RadioButton if the RadioButton has a Label. |
inputUssClassName |
.unity-radio-button__input |
USS class name of input elements in RadioButton elements. Unity adds this USS class to the input sub-element of the RadioButton . The input sub-element provides responses to the manipulator. |
checkmarkBackgroundUssClassName |
.unity-radio-button__checkmark-background |
USS class name of checkmark background in RadioButton elements. Unity adds this USS class to the checkmark background sub-element of the RadioButton . |
checkmarkUssClassName |
.unity-radio-button__checkmark |
USS class name of checkmark in RadioButton elements. Unity adds this USS class to the checkmark sub-element of the RadioButton . |
textUssClassName |
.unity-radio-button__text |
USS class name of Text elements in RadioButton elements. Unity adds this USS class to Text sub-elements of the RadioButton . |
ussClassName |
.unity-base-field |
USS class name of elements of this type. |
labelUssClassName |
.unity-base-field__label |
USS class name of labels in elements of this type. |
inputUssClassName |
.unity-base-field__input |
USS class name of input elements in elements of this type. |
noLabelVariantUssClassName |
.unity-base-field--no-label |
USS class name of elements of this type, when there is no label. |
labelDraggerVariantUssClassName |
.unity-base-field__label--with-dragger |
USS class name of labels in elements of this type, when there is a dragger attached on them. |
mixedValueLabelUssClassName |
.unity-base-field__label--mixed-value |
USS class name of elements that show mixed values |
alignedFieldUssClassName |
.unity-base-field__aligned |
USS class name of elements that are aligned in a inspector element |
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.