Step #1 : Adding the Calculator Buttons to the User Interface

Step #2 : Aligning the Buttons

Step #3 : Colors of Fonts, Buttons & Panels

Step #4 : Logic for Entering Numbers

Step #5 : Logic for Dot Button

Step #6 : Logic for Percentage Button

Step #7 : Logic for Plus Minus Toggle Button

Step #8 : Logic for Operators

Step #9 : Logic for Equals Button

Step #10 : Logic for Clear Button

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