From 30f0c9f94399c4a94ff9cf1fd7083e08ad473536 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20M=C3=BCllner?= <fmuellner@gnome.org>
Date: Tue, 2 Mar 2021 19:48:55 +0100
Subject: [PATCH] workspaceThumbnails: Update indicator on workspace changes

We block state updates while the indicator for the active workspace
is animating. To track that, we check whether the scroll-adjustment's
value matches the active workspace index. That works as long as the
adjustment's value changes after the active workspace, but not when
switching workspaces via SwipeTracker which only changes the active
workspace after transitioning to the new scroll value.

To fix that, update the indicator on workspace changes as well.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1716>
---
 js/ui/workspaceThumbnail.js | 39 +++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/js/ui/workspaceThumbnail.js b/js/ui/workspaceThumbnail.js
index 17d29d0d1..79c8df224 100644
--- a/js/ui/workspaceThumbnail.js
+++ b/js/ui/workspaceThumbnail.js
@@ -706,24 +706,13 @@ var ThumbnailsBox = GObject.registerClass({
         });
         this.connect('destroy', () => this._onDestroy());
 
-        this._switchWorkspaceNotifyId = 0;
         this._nWorkspacesNotifyId = 0;
+        this._activeWorkspaceChangedId = 0;
         this._syncStackingId = 0;
 
         this._scrollAdjustment = scrollAdjustment;
-
         this._scrollValueId = this._scrollAdjustment.connect('notify::value',
-            adj => {
-                const { workspaceManager } = global;
-                const activeIndex = workspaceManager.get_active_workspace_index();
-
-                this._animatingIndicator = adj.value !== activeIndex;
-
-                if (!this._animatingIndicator)
-                    this._queueUpdateStates();
-
-                this.queue_relayout();
-            });
+            () => this._updateIndicator());
     }
 
     _onDestroy() {
@@ -762,6 +751,19 @@ var ThumbnailsBox = GObject.registerClass({
         this.notify('should-show');
     }
 
+    _updateIndicator() {
+        const { value } = this._scrollAdjustment;
+        const { workspaceManager } = global;
+        const activeIndex = workspaceManager.get_active_workspace_index();
+
+        this._animatingIndicator = value !== activeIndex;
+
+        if (!this._animatingIndicator)
+            this._queueUpdateStates();
+
+        this.queue_relayout();
+    }
+
     _activateThumbnailAtPoint(stageX, stageY, time) {
         const [r_, x] = this.transform_stage_point(stageX, stageY);
 
@@ -992,6 +994,9 @@ var ThumbnailsBox = GObject.registerClass({
         this._nWorkspacesNotifyId =
             workspaceManager.connect('notify::n-workspaces',
                                      this._workspacesChanged.bind(this));
+        this._activeWorkspaceChangedId =
+            workspaceManager.connect('active-workspace-changed',
+                () => this._updateIndicator());
         this._workspacesReorderedId =
             workspaceManager.connect('workspaces-reordered', () => {
                 this._thumbnails.sort((a, b) => {
@@ -1019,13 +1024,17 @@ var ThumbnailsBox = GObject.registerClass({
         if (this._thumbnails.length == 0)
             return;
 
+        const { workspaceManager } = global;
+
         if (this._nWorkspacesNotifyId > 0) {
-            let workspaceManager = global.workspace_manager;
             workspaceManager.disconnect(this._nWorkspacesNotifyId);
             this._nWorkspacesNotifyId = 0;
         }
+        if (this._activeWorkspaceChangedId > 0) {
+            workspaceManager.disconnect(this._activeWorkspaceChangedId);
+            this._activeWorkspaceChangedId = 0;
+        }
         if (this._workspacesReorderedId > 0) {
-            let workspaceManager = global.workspace_manager;
             workspaceManager.disconnect(this._workspacesReorderedId);
             this._workspacesReorderedId = 0;
         }