From d6a2e1976e43e7eb9be88c2c07e5ed31ad76fded Mon Sep 17 00:00:00 2001
From: Konrad Materka <materka@gmail.com>
Date: Thu, 15 Apr 2021 22:57:28 +0200
Subject: [PATCH] [applets/systemtray] Fix highlight when applet comes back
 from hidden

Highlight should work correctly if selected applet changes state
and is moved to hidden area and then comes back to visble area.

BUG: 435687
FIXED-IN: 5.22.0
---
 .../contents/ui/CurrentItemHighLight.qml       | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/applets/systemtray/package/contents/ui/CurrentItemHighLight.qml b/applets/systemtray/package/contents/ui/CurrentItemHighLight.qml
index 5dc45c479..18fe20a49 100644
--- a/applets/systemtray/package/contents/ui/CurrentItemHighLight.qml
+++ b/applets/systemtray/package/contents/ui/CurrentItemHighLight.qml
@@ -54,6 +54,7 @@ PlasmaCore.FrameSvgItem {
             return prefix;
     }
 
+    // update when System Tray is expanded - applet activated or hidden icons shown
     Connections {
         target: systemTrayState
 
@@ -66,6 +67,7 @@ PlasmaCore.FrameSvgItem {
         }
     }
 
+    // update when applet changes parent (e.g. moves from active to hidden icons)
     Connections {
         target: systemTrayState.activeApplet
 
@@ -74,6 +76,7 @@ PlasmaCore.FrameSvgItem {
         }
     }
 
+    // update when System Tray size changes
     Connections {
         target: parent
 
@@ -86,9 +89,18 @@ PlasmaCore.FrameSvgItem {
         }
     }
 
+    // update when scale of newly added tray item changes (check 'add' animation in GridView in main.qml)
+    Connections {
+        target: !!highlightedItem && highlightedItem.parent ? highlightedItem.parent : null
+
+        function onScaleChanged() {
+            updateHighlightedItem();
+        }
+    }
+
     function updateHighlightedItem() {
         if (systemTrayState.expanded) {
-            if (systemTrayState.activeApplet && systemTrayState.activeApplet.parent.inVisibleLayout) {
+            if (systemTrayState.activeApplet && systemTrayState.activeApplet.parent && systemTrayState.activeApplet.parent.inVisibleLayout) {
                 changeHighlightedItem(systemTrayState.activeApplet.parent.container);
             } else { // 'Show hiden items' popup
                 changeHighlightedItem(parent);
@@ -100,8 +112,8 @@ PlasmaCore.FrameSvgItem {
 
     function changeHighlightedItem(nextItem) {
         // do not animate the first appearance
-        // or when size of parent (root) changes
-        if (!highlightedItem || (highlightedItem === nextItem && nextItem === parent)) {
+        // or when the property value of a highlighted item changes
+        if (!highlightedItem || (highlightedItem === nextItem)) {
             animationEnabled = false;
         }