Increase and Decrement Value of Variable with Button.LongClick

I am trying to increment/decrement the value of a variable using LongClick. There are two separate buttons for increment/decrement. The purpose is to increment/decrement as long as the relevant button is pressed. After the increment/decrement is done, the value is sent via Bluetooth. But I am unable to increment/decrement with the long button press. Can anyone help me with the logic on how to do it? 

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This previous post will help you understand how to do it using a clock.

Up Down bottons

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Thanks a lot Italo :) It helped a lot :) I'm finally able to increment and decrement a value using LongClick. Yeah! :D :) 

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