Fix BusyIndicator invisibility under Fusion style

When an initially invisible BusyIndicator is first made visible under
the Fusion style, it does not in actuality become visible. This is
because the QQuickFusionBusyIndicator::itemChange() function ignores
ItemVisibleHasChanged, so the appropriate actions don't take place. The
fix is a partial copy and paste of
QQuickMaterialBusyIndicator::itemChange's implementation which has
identical logic except for calling the appropriate ::itemChange() super
function.

Task-number: QTBUG-108808
Pick-to: 6.5
Change-Id: Id92c62a1eef4fc278ab91097f04db5b41a5d2c8a
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>
(cherry picked from commit 321110041143065a6939b157a0e85510ec5a0841)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 8f2aa4de88db7a4d5c7c35d30df0688fa1e52594)

2 files changed, 31 insertions, 3 deletions

diff --git a/src/quickcontrols/fusion/impl/qquickfusionbusyindicator.cpp b/src/quickcontrols/fusion/impl/qquickfusionbusyindicator.cpp
index cce69b0e4b..8e58b09ed3 100644
--- a/src/quickcontrols/fusion/impl/qquickfusionbusyindicator.cpp
+++ b/src/quickcontrols/fusion/impl/qquickfusionbusyindicator.cpp
@@ -71,8 +71,17 @@ void QQuickFusionBusyIndicator::itemChange(ItemChange change, const ItemChangeDa
 {
     QQuickPaintedItem::itemChange(change, data);
 
-    if (change == ItemOpacityHasChanged && qFuzzyIsNull(data.realValue))
-        setVisible(false);
+    switch (change) {
+    case ItemOpacityHasChanged:
+        if (qFuzzyIsNull(data.realValue))
+            setVisible(false);
+        break;
+    case ItemVisibleHasChanged:
+        update();
+        break;
+    default:
+        break;
+    }
 }
 
 QT_END_NAMESPACE
diff --git a/tests/auto/quickcontrols/controls/data/tst_busyindicator.qml b/tests/auto/quickcontrols/controls/data/tst_busyindicator.qml
index 7385677f93..69b1cc1d11 100644
--- a/tests/auto/quickcontrols/controls/data/tst_busyindicator.qml
+++ b/tests/auto/quickcontrols/controls/data/tst_busyindicator.qml
@@ -22,7 +22,14 @@ TestCase {
         id: mouseArea
         MouseArea { }
     }
-
+    
+    Component {
+        id: busyIndicatorInItem
+        Item {
+            BusyIndicator { }
+        }
+    }
+    
     function init() {
         failOnWarning(/.?/)
     }
@@ -63,4 +70,16 @@ TestCase {
         touch.release(0, control).commit()
         verify(!ma.pressed)
     }
+
+    // QTBUG-108808
+    function test_visibility() {
+        let control = createTemporaryObject(busyIndicatorInItem, testCase, {visible: false})
+        verify(control)
+
+        let invisibleImage = grabImage(control)
+        control.visible = true
+        let visibleImage = grabImage(control)
+
+        verify(!invisibleImage.equals(visibleImage))
+    }
 }