Bind to a list with ListView

Version: 2021.3+

The ListView control is the most efficient way to create lists. To bind to a list with ListView, set the binding path of the ListView to the name of the property that contains the list.

This example demonstrates how to bind to a list with ListView.

Example overview

The example creates a list of toggles and binds the list to an underlying list of GameSwitch objects.

You can find the completed files that this example creates in this GitHub repository.

先决条件

This guide is for developers familiar with the Unity Editor, UI Toolkit, and C# scripting. Before you start, get familiar with the following:

• Visual Tree
• UXML
• USS
• ListView

Create an object with a list

Create a GameSwitch object and a serialized object that has a list of GameSwitch objects as a property.

1. Create a Unity project with any template.

2. In your Project window, create a folder named bind-to-list to store all your files.

3. Create a C# script named GameSwitch.cs and replace its content with the following:

   using System;
   
   [Serializable]
   public struct GameSwitch
   {
       public string name;
       public bool enabled;
   }
   

4. Create a UI Document named game_switch.uxml and replace its contents with the following:

   <UXML xmlns="UnityEngine.UIElements" xmlns:ue="UnityEditor.UIElements">
       <Box style="flex-direction: row;">
           <Toggle binding-path="enabled" />
           <TextField binding-path="name" readonly="true" style="flex-grow: 1;"/>
       </Box>
   </UXML>
   

5. Create a C# script named GameSwitchListAsset.cs and replace its contents with the following:

   using System.Collections.Generic;
   using UnityEngine;
   
   namespace UIToolkitExamples
   {
       [CreateAssetMenu(menuName = "UIToolkitExamples/GameSwitchList")]
       public class GameSwitchListAsset : ScriptableObject
       {
           public List<GameSwitch> switches;
   
           public void Reset()
           {
               switches = new()
               {
                   new() { name = "Use Local Server", enabled = false },
                   new() { name = "Show Debug Menu", enabled = false },
                   new() { name = "Show FPS Counter", enabled = true },
               };
           }
   
           public bool IsSwitchEnabled(string switchName) => switches.Find(s => s.name == switchName).enabled;
       }
   }
   

Create a custom Editor and set the binding

Create a custom Editor that can create an asset with a list of toggles. Bind the toggle list to the GameSwitch list by setting the binding-path attribute of the UI Document to the property name of the GameSwitch list, which is switches.

1. Create a folder named Editor.

2. In the Editor folder, create a C# script named GameSwitchListEditor.cs and replace its contents with the following:

   using UnityEditor;
   using UnityEngine;
   using UnityEngine.UIElements;
   
   namespace UIToolkitExamples
   {
       [CustomEditor(typeof(GameSwitchListAsset))]
       public class GameSwitchListEditor : Editor
       {
           [SerializeField]
           VisualTreeAsset m_ItemAsset;
   
           [SerializeField]
           VisualTreeAsset m_EditorAsset;
   
           public override VisualElement CreateInspectorGUI()
           {
               var root = m_EditorAsset.CloneTree();
               var listView = root.Q<ListView>();
               listView.makeItem = m_ItemAsset.CloneTree;
               return root;
           }
       }
   }
   

3. Create a UI Document named game_switch_list_editor.uxml and replace its contents with the following:

   <UXML xmlns="UnityEngine.UIElements" xmlns:ue="UnityEditor.UIElements">
       <ListView virtualization-method="DynamicHeight"
                 reorder-mode="Animated"
                 binding-path="switches"
                 show-add-remove-footer="true"
                 show-border="true"
                 show-foldout-header="true"
                 header-title="Switches"
       />
   </UXML>
   

4. In the Project window, select GameSwitchListEditor.cs.

5. Drag game_switch.uxml to Item Asset in the Inspector.

6. Drag game_switch_list_editor.uxml to Editor Asset in the Inspector.

Test the binding

1. From the menu, select Assets > Create > UIToolkitExamples > GameSwitchList. This creates an asset named New Game Switch List Asset.
2. In the Project window, select New Game Switch List Asset. This shows a list of toggles in the Inspector. You can reorder the list, collapse it, add entries to or remove entries from the list, and change the number of entries in the list. If you make changes in the Inspector UI, the switches property of the GameSwitchListAsset object changes.

其他资源

• SerializedObject data binding
• Bindable elements
• Binding data type conversion
• Implementation details
• Binding examples