ListView

See the ListViewDemo.cs.

using Gridrand.Contracts;
using Gridrand.RimGui.Extensions;
using System.Collections.Generic;
namespace Gridrand.RimGui.Manual
{
    /// <summary>
    /// Demonstrates a list view with both non-scrolling and scrolling items.
    /// </summary>
    class ListViewDemo : ManualBase, IManual
    {
        // Manages item selection
        readonly ItemSelection<Item> selectedItems = new();
        readonly List<Item> nonScrollItems = new();
        readonly List<Item> scrollItems = new();
        readonly ItemDrawer itemDrawer;

        public ListViewDemo(ManualBaseResource p) : base(p)
        {
            itemDrawer = new ItemDrawer(Gui);

            for (int i = 0; i < 10; i++)
            {
                scrollItems.Add(new Item(i.ToString()));
                nonScrollItems.Add(new Item(i.ToString()));
            }
        }

        public void Draw()
        {
            // Display non-scrolling list view
            Gui.Heading("NonScroll");
            using (Style.Frame.Paddings.Begin(new(1, 1, 1, 1)))
            using (Gui.BeginFrame())
            {
                // Set SpacingY to 0 within this scope.
                using var s = Style.SpacingYs.Begin(0f);
                // Uses item drawer and selection handler
                Gui.ListView(
                    nonScrollItems,
                    new(itemDrawer, selectedItems, n => n.GetHashCode()),
                    null);
            }

            // Display scrolling list view
            Gui.Heading("Scroll");
            using (Style.Frame.Paddings.Begin(new(1, 1, 1, 1)))
            using (Gui.BeginFrame())
            using (Style.SpacingYs.Begin(0f))
                Gui.ScrollingListView(100f, scrollItems, new(itemDrawer, selectedItems, n => n.GetHashCode()));
        }

        /// <summary>
        /// Represents an item in the list.
        /// </summary>
        class Item
        {
            public string Name { get; }
            public bool IsChecked { get; set; }

            public Item(string name)
            {
                Name = name;
            }
        }

        /// <summary>
        /// Handles rendering of individual list items.
        /// </summary>
        class ItemDrawer : IListItemDrawer<Item>
        {
            readonly Gui ui;

            public ItemDrawer(Gui im)
            {
                this.ui = im;
            }

            /// <summary>
            /// Draws a list item with a checkbox and an index label.
            /// </summary>
            public void Draw(int index, Item item, Rect rect)
            {
                // note:Unscaled because the scale has already been taken into account.
                using var rects = ui.LayoutBuilder
                    .FixedUnscaled(rect.height)
                    .Fit(1)
                    .BuildHorizontal(rect);

                var isChecked = item.IsChecked;

                // Draws a checkbox, updating item state if changed
                if (ui.NextRect(rects.R0).CheckBox(ref isChecked))
                {
                    item.IsChecked = isChecked;
                }

                ui.NextRect(rects.R1).Text($"{index}");
            }
        }
    }

}