バージョン: 2021.2 以降
This example demonstrates how to create a custom control that displays a floating point number between 0 and 100. You can use it to display progress, as an alternative to a loading bar.
This example creates a RadialProgress element. It displays a progress value in a partially filled ring around a label that displays the percentage. It supports a value between 0 and 100, which determines how much of the ring is filled.
You can find the completed files that this example creates in this GitHub repository.
This is an advanced example for developers familiar with Unity Editor, UI Toolkit, and C# scripting. You are recommended to have a basic understanding of the following concepts:
Create a C# script to define a RadialProgress
visual element, and a C# script to define the custom mesh. Style the visual element with a USS file.
任意のテンプレートで Unity プロジェクトを作成します。
radial-progress
というフォルダーを作成し、ファイルを保存します。
In the RadialProgress
folder, create a C# scrip named RadialProgress.cs
and replace its contents with the following:
using Unity.Collections;
using UnityEngine;
using UnityEngine.UIElements;
namespace MyUILibrary
{
// An element that displays progress inside a partially filled circle
public class RadialProgress : VisualElement
{
public new class UxmlTraits : VisualElement.UxmlTraits
{
// The progress property is exposed to UXML.
UxmlFloatAttributeDescription m_ProgressAttribute = new UxmlFloatAttributeDescription()
{
name = "progress"
};
// The Init method is used to assign to the C# progress property from the value of the progress UXML
// attribute.
public override void Init(VisualElement ve, IUxmlAttributes bag, CreationContext cc)
{
base.Init(ve, bag, cc);
(ve as RadialProgress).progress = m_ProgressAttribute.GetValueFromBag(bag, cc);
}
}
// A Factory class is needed to expose this control to UXML.
public new class UxmlFactory : UxmlFactory<RadialProgress, UxmlTraits> { }
// These are USS class names for the control overall and the label.
public static readonly string ussClassName = "radial-progress";
public static readonly string ussLabelClassName = "radial-progress__label";
// These objects allow C# code to access custom USS properties.
static CustomStyleProperty<Color> s_TrackColor = new CustomStyleProperty<Color>("--track-color");
static CustomStyleProperty<Color> s_ProgressColor = new CustomStyleProperty<Color>("--progress-color");
// These are the meshes this control uses.
EllipseMesh m_TrackMesh;
EllipseMesh m_ProgressMesh;
// This is the label that displays the percentage.
Label m_Label;
// This is the number of outer vertices to generate the circle.
const int k_NumSteps = 200;
// This is the number that the Label displays as a percentage.
float m_Progress;
/// <summary>
/// A value between 0 and 100
/// </summary>
public float progress
{
// The progress property is exposed in C#.
get => m_Progress;
set
{
// Whenever the progress property changes, MarkDirtyRepaint() is named. This causes a call to the
// generateVisualContents callback.
m_Progress = value;
m_Label.text = Mathf.Clamp(Mathf.Round(value), 0, 100) + "%";
MarkDirtyRepaint();
}
}
// This default constructor is RadialProgress's only constructor.
public RadialProgress()
{
// Create a Label, add a USS class name, and add it to this visual tree.
m_Label = new Label();
m_Label.AddToClassList(ussLabelClassName);
Add(m_Label);
// Create meshes for the track and the progress.
m_ProgressMesh = new EllipseMesh(k_NumSteps);
m_TrackMesh = new EllipseMesh(k_NumSteps);
// Add the USS class name for the overall control.
AddToClassList(ussClassName);
// Register a callback after custom style resolution.
RegisterCallback<CustomStyleResolvedEvent>(evt => CustomStylesResolved(evt));
// Register a callback to generate the visual content of the control.
generateVisualContent += context => GenerateVisualContent(context);
progress = 0.0f;
}
static void CustomStylesResolved(CustomStyleResolvedEvent evt)
{
RadialProgress element = (RadialProgress)evt.currentTarget;
element.UpdateCustomStyles();
}
// After the custom colors are resolved, this method uses them to color the meshes and (if necessary) repaint
// the control.
void UpdateCustomStyles()
{
if (customStyle.TryGetValue(s_ProgressColor, out var progressColor))
{
m_ProgressMesh.color = progressColor;
}
if (customStyle.TryGetValue(s_TrackColor, out var trackColor))
{
m_TrackMesh.color = trackColor;
}
if (m_ProgressMesh.isDirty || m_TrackMesh.isDirty)
MarkDirtyRepaint();
}
// The GenerateVisualContent() callback method calls DrawMeshes().
static void GenerateVisualContent(MeshGenerationContext context)
{
RadialProgress element = (RadialProgress)context.visualElement;
element.DrawMeshes(context);
}
// DrawMeshes() uses the EllipseMesh utility class to generate an array of vertices and indices, for both the
// "track" ring (in grey) and the progress ring (in green). It then passes the geometry to the MeshWriteData
// object, as returned by the MeshGenerationContext.Allocate() method. For the "progress" mesh, only a slice of
// the index arrays is used to progressively reveal parts of the mesh.
void DrawMeshes(MeshGenerationContext context)
{
float halfWidth = contentRect.width * 0.5f;
float halfHeight = contentRect.height * 0.5f;
if (halfWidth < 2.0f || halfHeight < 2.0f)
return;
m_ProgressMesh.width = halfWidth;
m_ProgressMesh.height = halfHeight;
m_ProgressMesh.borderSize = 10;
m_ProgressMesh.UpdateMesh();
m_TrackMesh.width = halfWidth;
m_TrackMesh.height = halfHeight;
m_TrackMesh.borderSize = 10;
m_TrackMesh.UpdateMesh();
// Draw track mesh first
var trackMeshWriteData = context.Allocate(m_TrackMesh.vertices.Length, m_TrackMesh.indices.Length);
trackMeshWriteData.SetAllVertices(m_TrackMesh.vertices);
trackMeshWriteData.SetAllIndices(m_TrackMesh.indices);
// Keep progress between 0 and 100
float clampedProgress = Mathf.Clamp(m_Progress, 0.0f, 100.0f);
// Determine how many triangles are used to depending on progress, to achieve a partially filled circle
int sliceSize = Mathf.FloorToInt((k_NumSteps * clampedProgress) / 100.0f);
if (sliceSize == 0)
return;
// Every step is 6 indices in the corresponding array
sliceSize *= 6;
var progressMeshWriteData = context.Allocate(m_ProgressMesh.vertices.Length, sliceSize);
progressMeshWriteData.SetAllVertices(m_ProgressMesh.vertices);
var tempIndicesArray = new NativeArray<ushort>(m_ProgressMesh.indices, Allocator.Temp);
progressMeshWriteData.SetAllIndices(tempIndicesArray.Slice(0, sliceSize));
tempIndicesArray.Dispose();
}
}
}
Create a C# script named EllipseMesh.cs
and replace its contents with the following:
using UnityEngine;
using UnityEngine.UIElements;
namespace MyUILibrary
{
public class EllipseMesh
{
int m_NumSteps;
float m_Width;
float m_Height;
Color m_Color;
float m_BorderSize;
bool m_IsDirty;
public Vertex[] vertices { get; private set; }
public ushort[] indices { get; private set; }
public EllipseMesh(int numSteps)
{
m_NumSteps = numSteps;
m_IsDirty = true;
}
public void UpdateMesh()
{
if (!m_IsDirty)
return;
int numVertices = numSteps * 2;
int numIndices = numVertices * 6;
if (vertices == null || vertices.Length != numVertices)
vertices = new Vertex[numVertices];
if (indices == null || indices.Length != numIndices)
indices = new ushort[numIndices];
float stepSize = 360.0f / (float)numSteps;
float angle = -180.0f;
for (int i = 0; i < numSteps; ++i)
{
angle -= stepSize;
float radians = Mathf.Deg2Rad * angle;
float outerX = Mathf.Sin(radians) * width;
float outerY = Mathf.Cos(radians) * height;
Vertex outerVertex = new Vertex();
outerVertex.position = new Vector3(width + outerX, height + outerY, Vertex.nearZ);
outerVertex.tint = color;
vertices[i * 2] = outerVertex;
float innerX = Mathf.Sin(radians) * (width - borderSize);
float innerY = Mathf.Cos(radians) * (height - borderSize);
Vertex innerVertex = new Vertex();
innerVertex.position = new Vector3(width + innerX, height + innerY, Vertex.nearZ);
innerVertex.tint = color;
vertices[i * 2 + 1] = innerVertex;
indices[i * 6] = (ushort)((i == 0) ? vertices.Length - 2 : (i - 1) * 2); // previous outer vertex
indices[i * 6 + 1] = (ushort)(i * 2); // current outer vertex
indices[i * 6 + 2] = (ushort)(i * 2 + 1); // current inner vertex
indices[i * 6 + 3] = (ushort)((i == 0) ? vertices.Length - 2 : (i - 1) * 2); // previous outer vertex
indices[i * 6 + 4] = (ushort)(i * 2 + 1); // current inner vertex
indices[i * 6 + 5] = (ushort)((i == 0) ? vertices.Length - 1 : (i - 1) * 2 + 1); // previous inner vertex
}
m_IsDirty = false;
}
public bool isDirty => m_IsDirty;
void CompareAndWrite(ref float field, float newValue)
{
if (Mathf.Abs(field - newValue) > float.Epsilon)
{
m_IsDirty = true;
field = newValue;
}
}
public int numSteps
{
get => m_NumSteps;
set
{
m_IsDirty = value != m_NumSteps;
m_NumSteps = value;
}
}
public float width
{
get => m_Width;
set => CompareAndWrite(ref m_Width, value);
}
public float height
{
get => m_Height;
set => CompareAndWrite(ref m_Height, value);
}
public Color color
{
get => m_Color;
set
{
m_IsDirty = value != m_Color;
m_Color = value;
}
}
public float borderSize
{
get => m_BorderSize;
set => CompareAndWrite(ref m_BorderSize, value);
}
}
}
Create a USS file named RadialProgress.uss
and replace its contents with the following:
.radial-progress {
min-width: 26px;
min-height: 20px;
--track-color: rgb(130, 130, 130);
--progress-color: rgb(46, 132, 24);
--percentage-color: white;
margin-left: 5px;
margin-right: 5px;
margin-top: 5px;
margin-bottom: 5px;
flex-direction: row;
justify-content: center;
}
.radial-progress__label {
-unity-text-align: middle-left;
color: var(--percentage-color);
}
Utilize the custom control in a UI Document and test
Create a UI Document named RadialProgressExample.uxml
and replace its contents with the following:
<ui:UXML xmlns:ui="UnityEngine.UIElements" xmlns:uie="UnityEditor.UIElements" editor-extension-mode="False">
<ui:VisualElement style="align-items: center;">
<MyUILibrary.RadialProgress progress="87.1" style="width: 100px; height: 100px;" />
</ui:VisualElement>
</ui:UXML>
In Unity, open RadialProgressExample.uxml
in the UI Builder.
UI Builder の StyleSheets セクションに、既存の USS としてRadialProgress.uss
を加えます。
Select the RadialProgress in the Hierarchy window. If you enter different values in the Progress box in the Inspector, the percentage in the Viewport changes, and the green progress ring resizes.
Did you find this page useful? Please give it a rating:
Thanks for rating this page!
What kind of problem would you like to report?
Thanks for letting us know! This page has been marked for review based on your feedback.
If you have time, you can provide more information to help us fix the problem faster.
Provide more information
You've told us this page needs code samples. If you'd like to help us further, you could provide a code sample, or tell us about what kind of code sample you'd like to see:
You've told us there are code samples on this page which don't work. If you know how to fix it, or have something better we could use instead, please let us know:
You've told us there is information missing from this page. Please tell us more about what's missing:
You've told us there is incorrect information on this page. If you know what we should change to make it correct, please tell us:
You've told us this page has unclear or confusing information. Please tell us more about what you found unclear or confusing, or let us know how we could make it clearer:
You've told us there is a spelling or grammar error on this page. Please tell us what's wrong:
You've told us this page has a problem. Please tell us more about what's wrong:
Thank you for helping to make the Unity documentation better!
Your feedback has been submitted as a ticket for our documentation team to review.
We are not able to reply to every ticket submitted.