Show Preparing text after clicking Prepare button

CURA-5551

resources/qml/SaveButton.qml

@@ -168,6 +168,8 @@ Item {
         Button {
             id: prepareButton
 
+            property bool showPrepare : false;
+
             tooltip: [1, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@info:tooltip","Slice current printjob") : catalog.i18nc("@info:tooltip","Cancel slicing process")
             // 1 = not started, 2 = Processing
             enabled: base.backendState != "undefined" && ([1, 2].indexOf(base.backendState) != -1) && base.activity
@@ -180,9 +182,19 @@ Item {
             anchors.rightMargin: UM.Theme.getSize("sidebar_margin").width
 
             // 1 = not started, 4 = error, 5 = disabled
-            text: [1, 4, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@label:Printjob", "Prepare") : catalog.i18nc("@label:Printjob", "Cancel")
+            text: {
+
+                if (base.backendState == 1 && showPrepare)
+                {
+                    showPrepare = false
+                    return catalog.i18nc("@label:Printjob", "Preparing")
+                }
+
+                return [1, 4, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@label:Printjob", "Prepare") : catalog.i18nc("@label:Printjob", "Cancel")
+            }
             onClicked:
             {
+                showPrepare = true
                 sliceOrStopSlicing();
             }