DoubleSpinBox

import QtQuick 2.9
import QtQuick.Controls 2.2

import App 1.0

ApplicationWindow {
    width: 800
    height: 800
    visible: true

    SpinBox {
        id: control
        from: 0
        editable: true
        stepSize: realStepSize * factor
        value: realValue * factor
        to : realTo * factor
        anchors.centerIn: parent

        property int decimals: 6
        property real factor: Math.pow(10, decimals)
        property real realValue: 0.0
        property real realFrom: 0.0
        property real realTo: 100.0
        property real realStepSize: .0001

        onValueModified: print(realValue)

        validator: DoubleValidator {
            bottom: Math.min(control.from, control.to) * control.factor
            top:  Math.max(control.from, control.to) * control.factor
        }

        textFromValue: function(value, locale) {
            return Number(value * 1.0 / control.factor).toLocaleString(locale, 'f', control.decimals)
        }

        valueFromText: function(text, locale) {
            return Number.fromLocaleString(locale, text) * factor
        }
    }
}