Fix for weapon and potion images

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Engine;
using System.IO;


namespace MyLittleRPG
{
    public partial class MyLittleRPG : Form
    {
        private Player _player;
        private const string PLAYER_DATA_FILE_NAME = "PlayerData.xml";
        public MyLittleRPG()
        {
            InitializeComponent();


            //Create new player + giving base stats
            if (File.Exists(PLAYER_DATA_FILE_NAME))
            {
                _player = Player.CreatePlayerFromXmlString(File.ReadAllText(PLAYER_DATA_FILE_NAME));
            }
            else
            {
                _player = Player.CreateDefaultPlayer();
            }

            lblHitPoints.DataBindings.Add("Text", _player, "CurrentHitPoints");
            lblGold.DataBindings.Add("Text", _player, "Gold");
            lblExperience.DataBindings.Add("Text", _player, "ExperiencePoints");
            lblLevel.DataBindings.Add("Text", _player, "Level");
            

            dgvInventory.RowHeadersVisible = false;
            dgvInventory.AutoGenerateColumns = false;

            dgvInventory.DataSource = _player.Inventory;
            dgvInventory.Columns.Add(new DataGridViewTextBoxColumn
            {
                HeaderText = "Name",
                Width = 185,
                DataPropertyName = "Description"
            });
            dgvInventory.Columns.Add(new DataGridViewTextBoxColumn
            {
                HeaderText = "Quantity",
                DataPropertyName = "Quantity"
            });

            dgvQuests.RowHeadersVisible = false;
            dgvQuests.AutoGenerateColumns = false;

            dgvQuests.DataSource = _player.Quests;

            dgvQuests.Columns.Add(new DataGridViewTextBoxColumn
            {
                HeaderText = "Name",
                Width = 185,
                DataPropertyName = "Name"
            });
            dgvQuests.Columns.Add(new DataGridViewTextBoxColumn
            {
                HeaderText = "Done?",
                DataPropertyName="IsCompleted"
            });

            // Add the event handler BEFORE we have code
            // that might set cboWeapons.SelectedItem.
            // This includes the default selection of the first item,
            // when cboWeapons.DataSource is first set.
            cboWeapons.SelectedIndexChanged += cboWeapons_SelectedIndexChanged;

            cboWeapons.DataSource = _player.Weapons;
            cboWeapons.DisplayMember = "Name";
            cboWeapons.ValueMember = "Id";

            // If the player does not have a weapon,
            // and there are weapons available,
            // select the first weapon as the player's current weapon
            if (_player.CurrentWeapon == null && 
                _player.Weapons.Count > 0)
            {
                _player.CurrentWeapon = _player.Weapons[0];
            }

            if (_player.CurrentWeapon != null)
            {
                cboWeapons.SelectedItem = _player.CurrentWeapon;
            }

            // Add an event handler to watch if the player selects a potion.
            // This includes the default selection of the first item,
            // when cboPotions.DataSource is first set.
            cboPotions.SelectedIndexChanged += cboPotions_SelectedIndexChanged;

            cboPotions.DataSource = _player.Potions;
            cboPotions.DisplayMember = "Name";
            cboPotions.ValueMember = "Id";

            _player.PropertyChanged += PlayerOnPropertyChanged;
            _player.OnMessage += DisplayMessage;
            
            pctPlayer.Image = Properties.Resources.HumanWithSword;
        }

        private void DisplayMessage(object sender, MessageEventArgs messageEventArgs)
        {
            rtbMessages.Text += messageEventArgs.Message + Environment.NewLine;
            if (messageEventArgs.AddExtraNewLine)
            {
                rtbMessages.Text += Environment.NewLine;
            }
            rtbMessages.SelectionStart = rtbMessages.Text.Length;
            rtbMessages.ScrollToCaret();
        }
        private void PlayerOnPropertyChanged(object sender, PropertyChangedEventArgs propertyChangedEventArgs)
        {
            if (propertyChangedEventArgs.PropertyName=="Weapons")
            {
                cboWeapons.DataSource = _player.Weapons;
                if (!_player.Weapons.Any())
                {
                    cboWeapons.Visible = false;
                    btnUseWeapon.Visible = false;
                    pctWeapon.Image = null;
                }
            }
            if (propertyChangedEventArgs.PropertyName=="Potions")
            {
                cboPotions.DataSource = _player.Potions;
                if (!_player.Potions.Any())
                {
                    cboPotions.Visible = false;
                    btnUsePotion.Visible = false;
                    pctHealing.Image = null;
                } 
            }
            if (propertyChangedEventArgs.PropertyName == "CurrentLocation")
            {
                btnTrade.Visible = (_player.CurrentLocation.VendorWorkingHere != null);
                //Show/hide available movement
                btnNorth.Enabled = (_player.CurrentLocation.LocationToNorth != null);
                btnEast.Enabled = (_player.CurrentLocation.LocationToEast != null);
                btnSouth.Enabled = (_player.CurrentLocation.LocationToSouth != null);
                btnWest.Enabled = (_player.CurrentLocation.LocationToWest != null);

                //display current location name and description
                rtbLocation.Text = _player.CurrentLocation.Name + Environment.NewLine;
                rtbLocation.Text += _player.CurrentLocation.Description + Environment.NewLine;

                if (_player.CurrentLocation.MonsterLivingHere==null)
                {
                    cboWeapons.Visible = false;
                    cboPotions.Visible = false;
                    btnUseWeapon.Visible = false;
                    btnUsePotion.Visible = false;
                }
                else
                {
                    cboWeapons.Visible = _player.Weapons.Any();
                    cboPotions.Visible = _player.Weapons.Any();
                    btnUseWeapon.Visible = _player.Weapons.Any();
                    btnUsePotion.Visible = _player.Weapons.Any();
                }
            }
        }

        private void btnNorth_Click(object sender, EventArgs e)
        {
            _player.MoveNorth();
            ScrollToBottomMessages();
        }

        private void btnEast_Click(object sender, EventArgs e)
        {
            _player.MoveEast();
            ScrollToBottomMessages();
        }

        private void btnSouth_Click(object sender, EventArgs e)
        {
            _player.MoveSouth();
            ScrollToBottomMessages();
        }

        private void btnWest_Click(object sender, EventArgs e)
        {
            _player.MoveWest();
            ScrollToBottomMessages();
        }
       
        private void btnUseWeapon_Click(object sender, EventArgs e)
        {
            //Get the current selected weapon from cbobox
            Weapon currentWeapon = (Weapon)cboWeapons.SelectedItem;
            _player.UseWeapon(currentWeapon);
        }

        private void btnUsePotion_Click(object sender, EventArgs e)
        {
            //get the current selected potion from cbobox
            HealingPotion potion = (HealingPotion)cboPotions.SelectedItem;
            _player.UsePotion(potion);
        }
        private void ScrollToBottomMessages()
        {
            rtbMessages.SelectionStart = rtbMessages.Text.Length;
            rtbMessages.ScrollToCaret();
        }

        private void MyLittleRPG_FormClosing(object sender, FormClosingEventArgs e)
        {
            File.WriteAllText(PLAYER_DATA_FILE_NAME, _player.ToXmlString());
        }
        private void cboWeapons_SelectedIndexChanged(object sender, EventArgs e)
        {
            _player.CurrentWeapon = (Weapon)cboWeapons.SelectedItem;
            pctWeapon.Image = _player.CurrentWeapon?.Picture;
        }

        private void cboPotions_SelectedIndexChanged(object sender, EventArgs e)
        {
            pctHealing.Image = (cboPotions.SelectedItem as HealingPotion)?.Picture;
        }
        private void btnTrade_Click(object sender, EventArgs e)
        {
            TradingScreen tradingScreen = new TradingScreen(_player);
            tradingScreen.StartPosition = FormStartPosition.CenterParent;
            tradingScreen.ShowDialog(this);
        }
    }
}