Lazarus Tutorial #4 - The first calculator

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This video demonstrates the use of our variable knowledge from the last video. We will create our first small calculator, which can be used for calculating with integers. In the end of this video series you should be able to develop your own applications for Windows, Linux and Mac. Moreover you should have understood the concept of programming and the necessary knowledge to continue your journey.

Published: 2016-08-10
Views: 8288
Tags: Lazarus, Tutorial, Programming, Learning, Applications, Windows, Linux, Mac, Calculator, Variables


In this video, you have learned:

  • Designing a basic application
    • Edit (numbers only)
    • Label (change font settings)
    • Button
    • Move components using the keyboard: Ctrl + [Arrow-Keys]
    • Resize components using the keyboard: Ctrl + [Arrow-Keys]
  • Working with events
    • Button.OnClick
  • Working with local variables
    • Using local variables
    • Calculate formulas
    • StrToInt – casts a string into an integer
    • IntToStr – casts an integer to a string
  • Creating an executable


Project files :: 127 KB

This download contains the project files of this video.