JD2022-TU1/main/tools/modules/JD.SceneExplorer/ItemAdapters/DefaultTreeListBoxItemAdapter.cs

using System.Collections;
using System.Collections.ObjectModel;
using System.Linq;
using ActiproSoftware.Windows.Controls.Grids;
using JD.SceneExplorer.ViewModels;
using JD.WPF.Models;

namespace JD.SceneExplorer.ItemAdapters
{
    /// <summary>
    /// An adapter that can provide an item's hierarchy and visual state data for usage in a <see cref="TreeListBox"/>.
    /// This default implementation is intended to specifically adapt <see cref="TreeViewItemData"/>
    /// and is geared for high-performance due to the various get/set method overrides
    /// instead of using bindings for updates.
    /// </summary>
    public class DefaultTreeListBoxItemAdapter : TreeListBoxItemAdapter
    {

        /////////////////////////////////////////////////////////////////////////////////////////////////////
        // OBJECT
        /////////////////////////////////////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Initializes a new instance of the <see cref="DefaultTreeListBoxItemAdapter"/> class.
        /// </summary>
        public DefaultTreeListBoxItemAdapter()
        {
            // Setting these properties tells the adapter which properties to watch for INotifyPropertyChanged updates
            //   so that the UI can receive the updated values without binding usage
            ChildrenPath = "Children";
            IsEditingPath = "IsEditing";
            IsExpandedPath = "IsExpanded";
            IsLoadingPath = "IsLoading";
            IsSelectablePath = "IsSelectable";
            IsSelectedPath = "IsSelected";
        }

        /////////////////////////////////////////////////////////////////////////////////////////////////////
        // PUBLIC PROCEDURES
        /////////////////////////////////////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Returns an <see cref="IEnumerable"/> that will be used to provide child items for the specified parent item.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>An <see cref="IEnumerable"/> that will be used to provide child items for the specified parent item.</returns>
        public override IEnumerable GetChildren(TreeListBox ownerControl, object item)
        {
            if (item is ObjectWithRef model)
            {
                return model.Children;
            }

            return new ObservableCollection<ObjectWithRef>();
        }

        /// <summary>
        /// Returns whether the specified item is draggable.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is draggable; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsDraggable(TreeListBox ownerControl, object item)
        {
            return true;
        }

        /// <summary>
        /// Returns whether the specified item is editable.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is editable; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsEditable(TreeListBox ownerControl, object item)
        {
            return false;
        }

        /// <summary>
        /// Returns whether the specified item is currently being edited.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is currently being edited; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsEditing(TreeListBox ownerControl, object item)
        {
            return false;
        }

        /// <summary>
        /// Returns whether the specified item is expanded.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is expanded; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsExpanded(TreeListBox ownerControl, object item)
        {
            if (item is RootSceneTree)
            {
                return true;
            }
            
            if (item is ObjectWithRef model)
            {
                return model.IsExpanded;
            }
            return false;
        }

        /// <inheritdoc />
        public override TreeItemExpandability GetExpandability(TreeListBox ownerControl, object item, int depth)
        {
            if (item is ObjectWithRef model)
            {
                return model.Children.Any() ? TreeItemExpandability.Auto : TreeItemExpandability.Never;
            }
            return base.GetExpandability(ownerControl, item, depth);
        }

        /// <summary>
        /// Returns whether the specified item is currently loading children asynchronously.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is currently loading children asynchronously; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsLoading(TreeListBox ownerControl, object item)
        {
            return false;
        }

        /// <summary>
        /// Returns whether the specified item is capable of being selected.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is capable of being selected; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsSelectable(TreeListBox ownerControl, object item)
        {
            return true;
        }

        /// <summary>
        /// Returns whether the specified item is selected.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>
        /// <c>true</c> if the specified item is selected; otherwise, <c>false</c>.
        /// </returns>
        public override bool GetIsSelected(TreeListBox ownerControl, object item)
        {
            return (item is ObjectWithRef model && model.IsSelected);
        }

        /// <summary>
        /// Returns the item's string path.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>The item's string path.</returns>
        public override string GetPath(TreeListBox ownerControl, object item)
        {
            return (item is ObjectWithRef model ? model.FriendlyName : null);
        }

        /// <summary>
        /// Returns the item's text by which to match when searching.
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to examine.</param>
        /// <returns>The item's string search text.</returns>
        public override string GetSearchText(TreeListBox ownerControl, object item)
        {
            return (item is ObjectWithRef model ? model.FriendlyName : null);
        }

        /// <summary>
        /// Sets whether the specified item is currently being edited. 
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to update.</param>
        /// <param name="value">The new value.</param>
        public override void SetIsEditing(TreeListBox ownerControl, object item, bool value)
        {
            
        }

        /// <summary>
        /// Sets whether the specified item is expanded. 
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to update.</param>
        /// <param name="value">The new value.</param>
        public override void SetIsExpanded(TreeListBox ownerControl, object item, bool value)
        {
            if (item is ObjectWithRef model)
            {
                model.IsExpanded = value;
            }
        }

        /// <summary>
        /// Sets whether the specified item is selected. 
        /// </summary>
        /// <param name="ownerControl">The owner control.</param>
        /// <param name="item">The item to update.</param>
        /// <param name="value">The new value.</param>
        public override void SetIsSelected(TreeListBox ownerControl, object item, bool value)
        {
            if (item is ObjectWithRef model)
            {
                model.IsSelected = value;
            }
        }
    }
}