It's two days later and now the calculator can actually DO something! gasp
Added the following functions:
Equals button (I forgot this last time O_o)
Reset button will clear the panel while a sequence is in progress
Addition (between two integers)
Multiplication (between two integers)
Division (between two integers... no fractions just yet)
Subtraction (between two integers, includes negative answers)
Guard against user selecting more than one operator in succession (ex: 1 +- 2 is not a valid input)
What doesn't work:
Fractions
Operations involving more than three integers (1 + 1 + 1 will currently yield 12!)
No decimals
No negative number input
Thanks for watching! ^_^