AdvancedObjectSelectorValidatorAttribute

Description

This attribute lets you register a custom advanced object selector validator.

An advanced object selector is an object selector that can be customized programatically to be opened on specific object fields, without modifying the object fields themselves. It also allows total control over the UI, so you can create your own search window if you wish to. There are two methods that need to be registered: the object selector handler and the validator. The handler opens the object selector, and the validator validates that the object selector can be opened for the current selection context. Here is an example using Search to open a custom object selector only for materials:

using System;
using System.Linq;
using UnityEditor.Search;
using UnityEditor.SearchService;
using UnityEngine;

static class MaterialSelector
{
    const string MaterialSelectorId = "material_selector";
    static ISearchView s_SearchView;

    [AdvancedObjectSelectorValidator(MaterialSelectorId)]
    static bool HandleAdvancedObjectSelectorValidation(ObjectSelectorSearchContext context)
    {
        // This selector only works for assets.
        if ((context.visibleObjects & VisibleObjects.Assets) == 0)
            return false;

        // This selector only supports materials and their derived types.
        if (!OnlyMaterialTypes(context))
            return false;

        return true;
    }

    [AdvancedObjectSelector(MaterialSelectorId, "Material Selector", 10)]
    static void HandleAdvancedObjectSelector(AdvancedObjectSelectorEventType eventType, in AdvancedObjectSelectorParameters parameters)
    {
        switch (eventType)
        {
            case AdvancedObjectSelectorEventType.BeginSession:
                BeginSession(parameters);
                break;
            case AdvancedObjectSelectorEventType.EndSession:
                EndSession(parameters);
                break;
            case AdvancedObjectSelectorEventType.SetSearchFilter:
                SetSearchFilter(parameters);
                break;
            case AdvancedObjectSelectorEventType.OpenAndSearch:
                OpenSelector(parameters);
                break;
        };
    }

    static void BeginSession(in AdvancedObjectSelectorParameters parameters)
    {
        // Here you can cache some data if needed.
    }

    static void EndSession(in AdvancedObjectSelectorParameters parameters)
    {
        // Here you can clear the cached data if needed.
        // EndSession can be called in two ways:
        // 1. Naturally when the selectorClosedHandler is called upon closing the window (which you should do in your window if you don't use Search).
        // 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 ((parameters.context.endSessionModes & ObjectSelectorSearchEndSessionModes.CloseSelector) != 0)
        {
            s_SearchView?.Close();
        }

        s_SearchView = null;
    }

    static void SetSearchFilter(in AdvancedObjectSelectorParameters parameters)
    {
        // Here you can handle the request to set a new search filter.
        s_SearchView?.SetSearchText(parameters.searchFilter);
    }

    static void OpenSelector(in AdvancedObjectSelectorParameters parameters)
    {
        var selectContext = parameters.context;
        var selectorCloseHandler = parameters.selectorClosedHandler;
        var trackingHandler = parameters.trackingHandler;

        // This selector handles any kind of materials, but if a specific material type is passed
        // in the context, then only this type of material will be shown.
        var searchText = string.Join(" or ", selectContext.requiredTypeNames.Select(typeName => $"t={typeName}"));
        var searchContext = SearchService.CreateContext("asset", searchText);
        var viewState = SearchViewState.CreatePickerState("Material",
            searchContext,
            selectHandler: (item, canceled) => selectorCloseHandler(item?.ToObject(), canceled),
            trackingHandler: (item) => trackingHandler(item?.ToObject()), null);
        viewState.windowTitle = new GUIContent("Material Selector");
        viewState.position = SearchUtils.GetMainWindowCenteredPosition(new Vector2(600, 400));
        s_SearchView = SearchService.ShowPicker(viewState);
    }

    static bool OnlyMaterialTypes(ObjectSelectorSearchContext context)
    {
        var requiredTypes = context.requiredTypes.Zip(context.requiredTypeNames, (type, name) => new Tuple<Type, string>(type, name));
        return requiredTypes.All(typeAndName =>
        {
            return typeAndName.Item1 != null && typeof(Material).IsAssignableFrom(typeAndName.Item1) ||
                typeAndName.Item2.Contains("material", StringComparison.OrdinalIgnoreCase);
        });
    }
}

The signature of the method registered with the attribute AdvancedObjectSelectorAttribute must be the following:

static void HandleAdvancedObjectSelector(AdvancedObjectSelectorEventType eventType, in AdvancedObjectSelectorParameters parameters)

The signature of the method registered with the attribute AdvancedObjectSelectorValidatorAttribute must be the following:

static bool HandleAdvancedObjectSelectorValidation(ObjectSelectorSearchContext context)

Note: Those custom advanced object selectors are only active when the Object Selector Engine is set to "Advanced" (see Preferences/Search settings page).

Constructors