ObjectSelectorSearchEndSessionModes.CloseSelector

Description

The session is ending because the current object selector needs to be closed.

Here is an example of an object selector engine using CloseSelector to close the currently opened selector:

using System;
using UnityEditor.SearchService;
using Object = UnityEngine.Object;

[ObjectSelectorEngine]
class TestObjectSelectorSearchEngine : IObjectSelectorEngine
{
    public string name => "My Custom Engine";

    public void BeginSession(ISearchContext context)
    {
    }

    public void EndSession(ISearchContext context)
    {
        // EndSession can be called in two ways:
        // 1. Naturally when the onObjectSelectorClosed is called upon closing the window (which you should do in your window).
        // 2. Forcefully when a new session is started before the current one is finished.
        // In the second case, we need to close the window to avoid any issues since the ObjectSelector API does not support concurrent selectors.
        if ((((ObjectSelectorSearchContext)context).endSessionModes & ObjectSelectorSearchEndSessionModes.CloseSelector) != 0 && ObjectSelectorWindow.instance != null)
        {
            ObjectSelectorWindow.instance.Close();
        }
    }

    public void BeginSearch(ISearchContext context, string query)
    {
        // Not called.
    }

    public void EndSearch(ISearchContext context)
    {
        // Not called.
    }

    public bool SelectObject(ISearchContext context, Action<Object, bool> onObjectSelectorClosed, Action<Object> onObjectSelectedUpdated)
    {
        ObjectSelectorWindow.Show((ObjectSelectorSearchContext)context, onObjectSelectedUpdated, onObjectSelectorClosed);
        return true;
    }

    public void SetSearchFilter(ISearchContext context, string searchFilter)
    {
        ObjectSelectorWindow.instance.searchText = searchFilter;
    }
}

Here is the code for the selector window that comes with it:

using System;
using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEditor.SearchService;
using UnityEditor.UIElements;
using UnityEngine.UIElements;
using Object = UnityEngine.Object;

public class ObjectSelectorWindow : EditorWindow
{
    public class ItemInfo
    {
        public int instanceId;
        public string label;
        public bool isAsset;
        public GlobalObjectId globalObjectId;
    }

    static ObjectSelectorSearchContext s_Context;
    static Action<Object> s_OnSelectionChanged;
    static Action<Object, bool> s_OnSelectorClosed;
    public static ObjectSelectorWindow instance { get; private set; }

    List<ItemInfo> m_FilteredItems;
    ToolbarSearchField m_Searchbox;
    ListView m_ListView;
    string m_SearchText;
    ItemInfo m_CurrentItem;
    bool m_Canceled = true;

    public bool initialized { get; private set; } = false;

    public string searchText
    {
        get => m_SearchText;
        set
        {
            m_SearchText = value;
            FilterItems();
        }
    }

    public List<ItemInfo> allItems { get; private set; }

    public static void Show(ObjectSelectorSearchContext context, Action<Object> onSelectionChanged, Action<Object, bool> onSelectorClosed)
    {
        s_Context = context;
        s_OnSelectionChanged = onSelectionChanged;
        s_OnSelectorClosed = onSelectorClosed;

        // Create a window with CreateInstance, and show it.
        var window = CreateInstance<ObjectSelectorWindow>();
        instance = window;
        window.Show();
    }

    void Init()
    {
        m_SearchText = "";
        allItems = new List<ItemInfo>();
        m_FilteredItems = new List<ItemInfo>();

        if ((s_Context.visibleObjects & VisibleObjects.Assets) == VisibleObjects.Assets)
            allItems.AddRange(FetchAllAssets());
        if ((s_Context.visibleObjects & VisibleObjects.Scene) == VisibleObjects.Scene)
            allItems.AddRange(FetchAllGameObjects(s_Context));

        allItems.Sort((item, other) => item.label.CompareTo(other.label));
        m_FilteredItems.AddRange(allItems);
    }

    void OnEnable()
    {
        Init();

        m_Searchbox = new ToolbarSearchField();
        m_Searchbox.RegisterValueChangedCallback(SearchFilterChanged);
        m_Searchbox.style.flexGrow = 1;
        m_Searchbox.style.maxHeight = 16;
        m_Searchbox.style.width = Length.Percent(100f);
        m_Searchbox.style.marginRight = 4;
        rootVisualElement.Add(m_Searchbox);

        m_ListView = new ListView(m_FilteredItems, 16, MakeItem, BindItem);
        m_ListView.selectionChanged += ItemSelectionChanged;
        m_ListView.itemsChosen += ItemsChosen;
        m_ListView.style.flexGrow = 1;
        rootVisualElement.Add(m_ListView);

        // Initialize selection
        if (s_Context.currentObject != null)
        {
            var currentSelectedId = s_Context.currentObject.GetInstanceID();
            var selectedIndex = m_FilteredItems.FindIndex(item => item.instanceId == currentSelectedId);
            if (selectedIndex >= 0)
                m_ListView.selectedIndex = selectedIndex;
        }

        FinishInit();
    }

    void FinishInit()
    {
        EditorApplication.delayCall += () =>
        {
            m_ListView.Focus();
            initialized = true;
        };
    }

    void OnDisable()
    {
        // Call the onSelectorClosed callback when the window is closing.
        s_OnSelectorClosed?.Invoke(GetCurrentObject(), m_Canceled);
        instance = null;
    }

    void SearchFilterChanged(ChangeEvent<string> evt)
    {
        searchText = evt.newValue;
    }

    void FilterItems()
    {
        m_FilteredItems.Clear();
        m_FilteredItems.AddRange(allItems.Where(item => string.IsNullOrEmpty(searchText) || item.label.IndexOf(searchText, StringComparison.InvariantCultureIgnoreCase) >= 0));

        m_ListView.Rebuild();
    }

    void BindItem(VisualElement listItem, int index)
    {
        if (index < 0 || index >= m_FilteredItems.Count)
            return;

        var label = listItem as Label;
        if (label == null)
            return;
        label.text = m_FilteredItems[index].label;
    }

    static VisualElement MakeItem()
    {
        return new Label();
    }

    void ItemSelectionChanged(IEnumerable<object> selectedItems)
    {
        m_CurrentItem = selectedItems.FirstOrDefault() as ItemInfo;
        s_OnSelectionChanged?.Invoke(GetCurrentObject());
    }

    void ItemsChosen(IEnumerable<object> selectedItems)
    {
        m_CurrentItem = selectedItems.FirstOrDefault() as ItemInfo;
        m_Canceled = false;
        Close();
    }

    static IEnumerable<ItemInfo> FetchAllAssets()
    {
        var allPaths = AssetDatabase.GetAllAssetPaths();
        if (allPaths == null)
            yield break;

        var requiredTypes = s_Context.requiredTypeNames != null ? s_Context.requiredTypeNames.ToList() : new List<string>();
        foreach (var path in allPaths)
        {
            var type = AssetDatabase.GetMainAssetTypeAtPath(path);
            var typeName = type.FullName ?? "";
            if (requiredTypes.Any(requiredType => typeName.Contains(requiredType)))
            {
                var asset = AssetDatabase.LoadMainAssetAtPath(path);
                var globalObjectId = GlobalObjectId.GetGlobalObjectIdSlow(asset);
                var instanceId = asset?.GetInstanceID() ?? 0;
                yield return new ItemInfo { instanceId = instanceId, label = path, isAsset = true, globalObjectId = globalObjectId };
            }
        }
    }

    static IEnumerable<ItemInfo> FetchAllGameObjects(ObjectSelectorSearchContext context)
    {
        var property = new HierarchyProperty(HierarchyType.GameObjects, false);

        var requiredTypes = s_Context.requiredTypeNames != null ? s_Context.requiredTypeNames.ToList() : new List<string>();
        while (property.Next(null))
        {
            var objectReferenced = property.pptrValue;
            if (objectReferenced == null)
                continue;
            var globalObjectId = GlobalObjectId.GetGlobalObjectIdSlow(property.instanceID);
            var typeName = objectReferenced.GetType().FullName ?? "";
            if (requiredTypes.Any(requiredType => typeName.Contains(requiredType)))
                yield return new ItemInfo { instanceId = property.instanceID, label = property.name, isAsset = false, globalObjectId = globalObjectId };
        }
    }

    Object GetCurrentObject()
    {
        if (m_CurrentItem == null)
            return null;
        var currentInstanceId = m_CurrentItem.instanceId;
        if (m_CurrentItem.isAsset)
        {
            var asset = AssetDatabase.LoadMainAssetAtPath(m_CurrentItem.label);
            currentInstanceId = asset.GetInstanceID();
        }
        return EditorUtility.InstanceIDToObject(currentInstanceId);
    }
}