Custom event not added to event section of properties panel

[FujiFilm]

I am attempting to add a custom event to the event section of properties panel for my custom control. The problem is no event is being added to the panel for me to subscribe to.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace LabelTextBox
{    
    public partial class ctlLabelTextbox : UserControl
    {
        public enum PositionEnum
        {
            Right,
            Below
        }

        private PositionEnum position = PositionEnum.Right;
        private int textboxMargin = 0;
        private string labelText = "";

        public event System.EventHandler PositionChanged;

        public string LabelText
        {
            get { return labelCaption.Text; }
            set
            {
                labelCaption.Text = labelText = value;
                MoveControls();
            }
        }
        
        public string TextboxText
        {
            get { return textBoxText.Text; }
            set
            {
                textBoxText.Text = value;
            }
        }
        
        public PositionEnum Position
        {
            get { return position; }
            set
            {
                position = value;
                MoveControls();
            }
        }

        public int TextboxMargin
        {
            get { return textboxMargin; }
            set
            {
                textboxMargin = value;
                MoveControls();
                if (PositionChanged != null)
                    PositionChanged(this, new EventArgs());
            }
        }

        public ctlLabelTextbox()
        {
            InitializeComponent();
        }



        private void ctlLabelTextbox_Load(object sender, EventArgs e)
        {
            labelCaption.Text = labelText;
            Height = textBoxText.Height > labelCaption.Height ? textBoxText.Height : labelCaption.Height;
            MoveControls();
        }

        private void ctlLabelTextbox_SizeChanged(object sender, EventArgs e)
        {
            MoveControls();
        }

        private void MoveControls()
        {
            switch (position)
            {
                case PositionEnum.Below:
                    textBoxText.Top = labelCaption.Bottom;
                    textBoxText.Left = labelCaption.Left;
                    textBoxText.Width = Width;
                    Height = textBoxText.Height + labelCaption.Height;
                    break;
                case PositionEnum.Right:
                    textBoxText.Top = labelCaption.Top;
                    if (textboxMargin == 0)
                    {
                        int width = Width - labelCaption.Width - 3;
                        textBoxText.Left = labelCaption.Right + 3;
                        textBoxText.Width = width;
                    }
                    else
                    {
                        textBoxText.Left = textboxMargin + labelCaption.Width;
                        textBoxText.Width = Width - textBoxText.Left;
                    }
                    Height = textBoxText.Height > labelCaption.Height ?
                    textBoxText.Height : labelCaption.Height;
                    break;
            }
        }

        private void textBoxText_KeyDown(object sender, KeyEventArgs e)
        {
            OnKeyDown(e);
        }

        private void textBoxText_KeyPress(object sender, KeyPressEventArgs e)
        {
            OnKeyPress(e);
        }

        private void textBoxText_KeyUp(object sender, KeyEventArgs e)
        {
            OnKeyUp(e);
        }
    }
}

I downloaded the source code for this since it is from a book and the source code didn't have the a event handler for the event and the event wasn't in the event section of properties for the custom control.