SearchProvider 类

SearchProvider 类执行特定类型项的搜索，并管理缩略图、说明和子筛选器。

它具有以下基本 API：

public class SearchProvider
{
    public SearchProvider(string id, string displayName = null);

    // Creates an Item bound to this provider.
    public SearchItem CreateItem(string id, string label = null, string description = null, Texture2D thumbnail = null);

    // Utility functions to check whether the search text matches a string.
    public static bool MatchSearchGroups(string searchContext, string content);
    public static bool MatchSearchGroups(string searchContext, string content,
                                        out int startIndex, out int endIndex);

    // The provider's unique ID.
    public NameId name;
    // Text token to "filter" a provider (for example, "me:", "p:", and "s:").
    public string filterId;
    // This provider is only active when a search explicitly specifies it with
    // its filterId.
    public bool isExplicitProvider;
    // Handler to fetch and format the label of a search item.
    public FetchStringHandler fetchLabel;
    // Handler to provide an async description for an item. Called just before
    // Search displays the item.
    // Allows a plug-in provider to fetch long descriptions only when
    // Search needs them.
    public FetchStringHandler fetchDescription;
    // Handler to provider an async thumbnail for an item. Called just before
    // Search displays the item.
    // Allows a plug-in provider to fetch/generate previews only when
    // Search needs them.
    public PreviewHandler fetchThumbnail;
    // Handler to support drag interactions. It is up to the SearchProvider
    // to properly set up the DragAndDrop manager.
    public StartDragHandler startDrag;
    // Called when the selection changes and Search can track it.
    public TrackSelectionHandler trackSelection;
    // MANDATORY: Handler to get items for a search context.
    public GetItemsHandler fetchItems;
    // A Search Provider can return a list of words that help the user complete
    // their search query.
    public GetKeywordsHandler fetchKeywords;
    // List of sub-filters that are visible in the FilterWindow for a
    // SearchProvider (see AssetProvider for an example).
    public List<NameId> subCategories;
    // Called when the Search window opens. Allows the Provider to perform
    // some caching.
    public Action onEnable;
    // Called when the Search window closes. Allows the Provider to release
    // cached resources.
    public Action onDisable;
    // Int to sort the Provider. Affects the order of search results and the
    // order in which providers are shown in the FilterWindow.
    public int priority;
    // Called when Search opens in "contextual mode". If you return true
    // it means the provider is enabled for this search context.
    public IsEnabledForContextualSearch isEnabledForContextualSearch;
}

缓存和释放资源

当您启动搜索窗口时，它会调用onEnable，您可以使用它来缓存资源。

当您关闭搜索窗口时，它会调用onDisable，您可以使用它来释放资源。

初始化

由于搜索项列表使用虚拟滚动算法，因此某些SearchItem字段（例如，label,thumbnail和description）如果尚未提供，则按需获取。

要在创建项后填充这些字段，您需要初始化SearchProvider使用特定的处理程序 （fetchLabel,fetchDescription,fetchThumbnail).

跟踪项目选择

您可以在trackSelection以使“搜索”在你使用鼠标或键盘选择搜索结果中的项目时执行某些作。例如，资产可在游戏或项目中使用的任何媒体或数据。资产可能来自在 Unity 外部创建的文件，例如 3D 模型、音频文件或图像。您还可以在 Unity 中创建一些资产类型，例如动画师控制器、混音器或渲染纹理。更多信息
请参阅术语表和场景场景包含游戏的环境和菜单。将每个唯一的场景文件视为一个独特的关卡。在每个场景中，你放置你的环境、障碍物和装饰品，基本上是将你的游戏设计和构建成碎片。更多信息
请参阅术语表提供程序使用trackSelection回调以 ping 搜索中的选定项目。

启用拖放

某些搜索提供程序返回可以拖放到场景中的项目。如果要创建项支持拖放的自定义提供程序，请实现startDrag.

例如，资产和场景提供程序填充DragAndDrop结构与相关项目 UID 进行交互，以允许适当的拖放交互。

在上下文搜索中包含提供程序

当您使用 Alt Shift + C 快捷键打开“搜索”窗口时，它会启动上下文搜索，这意味着“搜索”会搜索具有焦点的窗口。

当您启动上下文搜索时，覆盖的提供商isEnabledForContextualSearch检查是否应启用它们，如以下示例所示：

// Taken from Scene hierarchy provider:
// Makes the provider part of the contextual search if the Scene view or the
// Hierarchy window has focus.
isEnabledForContextualSearch = () =>
                QuickSearchTool.IsFocusedWindowTypeName("SceneView") ||
                QuickSearchTool.IsFocusedWindowTypeName("SceneHierarchyWindow");