Index: sources/gui/qml/components/Slider.qml
===================================================================
diff -u -r38cb7a4ff6d12878d078fb10c8d6915a31dc1df9 -ra070e7cd1dc7dcb4ba7fc5906c195357fe95d2f9
--- sources/gui/qml/components/Slider.qml	(.../Slider.qml)	(revision 38cb7a4ff6d12878d078fb10c8d6915a31dc1df9)
+++ sources/gui/qml/components/Slider.qml	(.../Slider.qml)	(revision a070e7cd1dc7dcb4ba7fc5906c195357fe95d2f9)
@@ -1,16 +1,16 @@
 /*!
- * 
- * Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
+ *
+ * Copyright (c) 2020-2023 Diality Inc. - All Rights Reserved.
  * \copyright
  * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
  * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
- * 
- * \file Slider.qml
- * \author (last) Peter Lucia
- * \date (last) 15-Oct-2020
- * \author (original) Behrouz NematiPour
- * \date (original) 18-Mar-2020
- * 
+ *
+ * \file    Slider.qml
+ * \author  (last)      Behrouz NematiPour
+ * \date    (last)      10-Feb-2023
+ * \author  (original)  Behrouz NematiPour
+ * \date    (original)  18-Mar-2020
+ *
  */
 
 // Qt
@@ -36,10 +36,13 @@
 
     property alias  handler            : _handler
     property alias  handlerColor       : _handler.color
+    property alias  handlerVisible     : _handler.visible
 
     property alias  diameter           : _handler.diameter
 
     property bool   isActive           : true
+    property bool   inActiveZero       : false  // if inActiveZero:true, when is not active (inActive or active:false) sets to zero instead of minimum
+
     property alias  progressRectMargin : _progressRect.margin
 
     property int    tickMarksThickness : 2
@@ -48,6 +51,43 @@
     signal progressRectDragged()
     signal activeChanged()
 
+    function incrementValue (vInStepSegments) {
+        // in case the slider is not yet activated, activate
+        if (!isActive) {
+            setActive(true)
+        }
+        updateValue(vInStepSegments, true)
+    }
+
+    function decrementValue (vInStepSegments) {
+        // in case the slider is not yet activated, activate
+        if (!isActive) {
+            setActive(true)
+        }
+        updateValue(vInStepSegments, false)
+    }
+
+    function updateValue(vInStepSegments, vIsIncrement) {
+        let amountChanged = 1
+        if (vInStepSegments) {
+            amountChanged = step
+        }
+
+        let newValue = Number.NaN
+        if(vIsIncrement) {
+            newValue = _root.value + amountChanged
+        } else {
+            newValue = _root.value - amountChanged
+        }
+
+        // Capping values based on min/max threshold
+        if ( newValue < minimum ) newValue = minimum
+        if ( newValue > maximum ) newValue = maximum
+
+        // update new value
+        update(newValue.toFixed(decimal))
+    }
+
     function setActive(active) {
         if (active) {
             color = Colors.createTreatmentActive
@@ -66,7 +106,7 @@
     onIsActiveChanged: {
         setActive(isActive)
         if (!isActive) {
-            value = minimum
+            value = inActiveZero ? 0 : minimum
         }
         activeChanged()
     }
@@ -104,22 +144,34 @@
         return ( x * ( maximum - minimum ) ) / width + minimum
     }
 
+    function update(vValue) {
+        _root.value = vValue
+    }
+
     function setValue(x) {
-        if ( x <     0 ) { value = minimum;                             return; }
-        if ( x > width ) { value = maximum;                             return; }
+        let mValue = 0
+        let mMinimum = Number(_root.minimum.toFixed(decimal))
+        let mMaximum = Number(_root.maximum.toFixed(decimal))
+        if ( x <     0 ) { mValue = mMinimum;                           update(mValue); return; }
+        if ( x > width ) { mValue = mMaximum;                           update(mValue); return; }
 
-        value = getValueOfX(x)
+        mValue = getValueOfX(x)
 
-        if ( step === 1 ) { value = parseInt(value);                    return; }
+        if ( step === 1 ) { mValue = parseInt(mValue);                  update(mValue); return; }
 
-        var start = 0
-        if ( ! stepSnap ) start = minimum
-        value = Math.round((value - start) / step) * step + start
+        let start = 0
+        if ( ! stepSnap ) start = mMinimum
+        mValue = Math.round((mValue - start) / step) * step + start
+
         let decimals = Math.round(-Math.log10(step))
-        if (decimals > 0) value = value.toFixed(decimals)
+        if (decimals > 0) {
+            mValue = mValue.toFixed(decimals)
+        }
 
-        if ( value < minimum ) { value = minimum;                       return; }
-        if ( value > maximum ) { value = maximum;                       return; }
+        if ( mValue < mMinimum ) { mValue = mMinimum;                   update(mValue); return; }
+        if ( mValue > mMaximum ) { mValue = mMaximum;                   update(mValue); return; }
+
+                                                                        update(mValue); return;
     }
 
     function setHandlerPosition() {
@@ -203,7 +255,7 @@
         radius  : diameter
         color   : Colors.highlightProgressBar
         border  {
-            width: 4
+            width: Variables.progressbarHandlerBorderWidth
             color: Colors.textMain
         }
     }