Fixed porting issues, mute warnings

src/qml/instruments/Ukulele.qml

@@ -3,7 +3,7 @@
  * on the terms of GNU GPLv3 license (http://www.gnu.org/licenses)   */
 
 import Nootka 1.0
-import QtGraphicalEffects 1.0
+import Qt5Compat.GraphicalEffects
 import QtQuick 2.12
 
 TguitarBg {

src/qml/score/Score.qml

@@ -87,7 +87,7 @@ Flickable {
             score.lastStaff = staves[staves.length - 1];
         }
         onStavesHeightChanged: score.contentHeight = Math.max(stavesHeight, score.height)
-        onStaffDestroying: {
+        onStaffDestroying: staffNr => {
             staves.splice(staffNr, 1);
             lastStaff = staves[staves.length - 1];
         }

src/qml/settings/Select7note.qml

@@ -29,7 +29,7 @@ Item {
         verticalItemAlignment: Grid.AlignVCenter
 
         ButtonGroup {
-            buttons: butRow.children
+            id: bhGr
         }
 
         Row {
@@ -47,10 +47,12 @@ Item {
             TradioButton {
                 id: bButt
 
+                ButtonGroup.group: bhGr
                 text: "B"
             }
 
             TradioButton {
+                ButtonGroup.group: bhGr
                 text: "H"
                 checked: !bButt.checked
             }