To display items taken by the player on a panel.
Inventory uses Vector to store all the items taken by the player and shows them on the panel. Wheneven
the player takes another new item or remove an item or move the scroll bar, it will update and repaint
the panel.
Variables
vt: This is a Vector used to store the items taken by the player.
InvDisp: The type is InvDisplay.
Methods
addItem(mazeObject) : Add an item to the vector and update the canvas.
removeItem(mazeObject) : Remove an item from the vector and update the canvas.