[ui] NodeEditor: Addressed the issue with retaining tabs when switching node selection

Updated the event trigger to be onVisibleChanged and the condition to check whether the current selected node is an incomputable node and the current tab index does not exist for it before resetting the index to 0

Author: waaake

meshroom/ui/qml/GraphEditor/NodeEditor.qml

@@ -372,6 +372,9 @@ Panel {
 
             property bool isComputable: root.node !== null && root.node.isComputable
 
+            // The indices of the tab bar which can be shown for incomputable nodes
+            readonly property var nonComputableTabIndices: [0, 4, 5];
+
             Layout.fillWidth: true
             width: childrenRect.width
             position: TabBar.Footer
@@ -415,9 +418,11 @@ Panel {
                 rightPadding: leftPadding
             }
 
-            onIsComputableChanged: {
-                if (!isComputable) {
-                    tabBar.currentIndex = 0
+            onVisibleChanged: {
+                // If we have a node selected and the node is not Computable
+                // Reset the currentIndex to 0, if the current index is not allowed for an incomputable node
+                if ((root.node && !root.node.isComputable) && (nonComputableTabIndices.indexOf(tabBar.currentIndex) === -1)) {
+                    tabBar.currentIndex = 0;
                 }
             }
         }