tbd-station-14/Content.Client/GameObjects/Components/StackComponent.cs

using Content.Client.UserInterface;
using Content.Client.Utility;
using Content.Shared.GameObjects.Components;
using Robust.Client.UserInterface;
using Robust.Client.UserInterface.Controls;
using Robust.Shared.GameObjects;
using Robust.Shared.Localization;
using Robust.Shared.Timing;
using Robust.Shared.ViewVariables;

namespace Content.Client.GameObjects.Components
{
    [RegisterComponent]
    public class StackComponent : SharedStackComponent, IItemStatus
    {
        [ViewVariables] public int Count { get; private set; }
        [ViewVariables] public int MaxCount { get; private set; }

        [ViewVariables(VVAccess.ReadWrite)] private bool _uiUpdateNeeded;

        public Control MakeControl() => new StatusControl(this);

        public override void HandleComponentState(ComponentState curState, ComponentState nextState)
        {
            if (!(curState is StackComponentState cast))
                return;

            Count = cast.Count;
            MaxCount = cast.MaxCount;
            _uiUpdateNeeded = true;
        }

        private sealed class StatusControl : Control
        {
            private readonly StackComponent _parent;
            private readonly RichTextLabel _label;

            public StatusControl(StackComponent parent)
            {
                _parent = parent;
                _label = new RichTextLabel {StyleClasses = {NanoStyle.StyleClassItemStatus}};
                AddChild(_label);

                parent._uiUpdateNeeded = true;
            }

            protected override void Update(FrameEventArgs args)
            {
                base.Update(args);

                if (!_parent._uiUpdateNeeded)
                {
                    return;
                }

                _parent._uiUpdateNeeded = false;

                _label.SetMarkup(Loc.GetString("Count: [color=white]{0}[/color]", _parent.Count));
            }
        }
    }
}