- Qt 5.15
- Qt Quick Demo - Calqlatr
- Qt 5.15.12 Reference Documentation

# Qt Quick Demo - Calqlatr

     /****************************************************************************
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     ** Copyright (C) 2017 The Qt Company Ltd.
     ** Contact: https://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
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     ** Alternatively, you may use this file under the terms of the BSD license
     ** as follows:
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     ** modification, are permitted provided that the following conditions are
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     var curVal = 0
     var memory = 0
     var lastOp = ""
     var previousOperator = ""
     var digits = ""

     function disabled(op) {
         if (digits == "" && !((op >= "0" && op <= "9") || op == "."))
             return true
         else if (op == '=' && previousOperator.length != 1)
             return true
         else if (op == "." && digits.toString().search(/\./) != -1) {
             return true
         } else if (op == "√" &&  digits.toString().search(/-/) != -1) {
             return true
         } else {
             return false
         }
     }

     function digitPressed(op)
     {
         if (disabled(op))
             return
         if (digits.toString().length >= display.maxDigits)
             return
         if (lastOp.toString().length == 1 && ((lastOp >= "0" && lastOp <= "9") || lastOp == ".") ) {
             digits = digits + op.toString()
             display.appendDigit(op.toString())
         } else {
             digits = op
             display.appendDigit(op.toString())
         }
         lastOp = op
     }

     function operatorPressed(op)
     {
         if (disabled(op))
             return
         lastOp = op

         if (op == "±") {
                 digits = Number(digits.valueOf() * -1)
                 display.setDigit(display.displayNumber(digits))
                 return
             }

         if (previousOperator == "+") {
             digits = Number(digits.valueOf()) + Number(curVal.valueOf())
         } else if (previousOperator == "−") {
             digits = Number(curVal.valueOf()) - Number(digits.valueOf())
         } else if (previousOperator == "×") {
             digits = Number(curVal) * Number(digits.valueOf())
         } else if (previousOperator == "÷") {
             digits = Number(curVal) / Number(digits.valueOf())
         }

         if (op == "+" || op == "−" || op == "×" || op == "÷") {
             previousOperator = op
             curVal = digits.valueOf()
             digits = ""
             display.displayOperator(previousOperator)
             return
         }

         if (op == "=") {
             display.newLine("=", digits.valueOf())
         }

         curVal = 0
         previousOperator = ""

         if (op == "1/x") {
             digits = (1 / digits.valueOf()).toString()
         } else if (op == "x^2") {
             digits = (digits.valueOf() * digits.valueOf()).toString()
         } else if (op == "Abs") {
             digits = (Math.abs(digits.valueOf())).toString()
         } else if (op == "Int") {
             digits = (Math.floor(digits.valueOf())).toString()
         } else if (op == "√") {
             digits = Number(Math.sqrt(digits.valueOf()))
             display.newLine("√", digits.valueOf())
         } else if (op == "mc") {
             memory = 0;
         } else if (op == "m+") {
             memory += digits.valueOf()
         } else if (op == "mr") {
             digits = memory.toString()
         } else if (op == "m-") {
             memory = digits.valueOf()
         } else if (op == "backspace") {
             digits = digits.toString().slice(0, -1)
             display.clear()
             display.appendDigit(digits)
         } else if (op == "Off") {
             Qt.quit();
         }

         // Reset the state on 'C' operator or after
         // an error occurred
         if (op == "C" || display.isError) {
             display.clear()
             curVal = 0
             memory = 0
             lastOp = ""
             digits = ""
         }
     }