Hello everyone. I have been assigned as a "Final" to code a Visual Basic program that takes concession stand orders, adds the items to a list, then figures the change.

This is a picture of the interface I designed to give you all the right idea.


Code:
    Private Sub xAddHamburgerButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles xAddHamburgerButton.Click
        Dim total As Double

        Double.TryParse(Me.xTotalLabel.Text, total)

        total = total + 2

        Me.xTotalLabel.Text = total.ToString("C2")

        Me.xItemsListBox.Items.Add("Hamburger   $2.00")
    End Sub
This code works to a point. It adds the $2.00 in the total box, but keeps it there even if I press the "add" button next to "hamburger" again. I would like that total to stack every time I press the button so it keeps a running total of everything purchased(and go on when I add other items, like "pizza" to the listbox).

Also this code isn't doing what is desired.

Code:
    Private Sub xChangeButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles xChangeButton.Click
        Dim amount As Integer
        Dim total As Integer
        Dim change As Integer

        Integer.TryParse(Me.xAmountRecievedTextBox.Text, amount)
        Integer.TryParse(Me.xTotalLabel.Text, total)
        Integer.TryParse(Me.xChangeLabel.Text, change)

        change = amount - total

        Me.xChangeLabel.Text = change.ToString("C2")
    End Sub
This picture demonstrates what happens:

And one last thing. What code would I use to make it remove a selected item from the list box? (xItemsListBox)

Any help would be greatly appreciated. Sorry if I sound like a newbie... but I am.