Index: sources/gui/qml/components/Slider.qml
===================================================================
diff -u -raf8d98b36b427e2b5f4d6659fcf3b58ee79eab6a -rf3a336a173b0fc1198a2e13d9da36d06dc911fcc
--- sources/gui/qml/components/Slider.qml	(.../Slider.qml)	(revision af8d98b36b427e2b5f4d6659fcf3b58ee79eab6a)
+++ sources/gui/qml/components/Slider.qml	(.../Slider.qml)	(revision f3a336a173b0fc1198a2e13d9da36d06dc911fcc)
@@ -51,6 +51,39 @@
     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
+
+        // Calculate the x position of the new value
+        let divisor = (maximum != minimum) ? (maximum - minimum) : 1
+        let calculatedX = ((newValue - minimum) * _root.width) / divisor
+        setValue(calculatedX)
+    }
+
     function setActive(active) {
         if (active) {
             color = Colors.createTreatmentActive