From e62b3fecbb7c3a35a32ca9b3724820d3ee68686f Mon Sep 17 00:00:00 2001
From: Thiemo Kreuz <thiemo.kreuz@wikimedia.de>
Date: Mon, 13 Sep 2021 13:42:20 +0200
Subject: [PATCH] Optimize .selectPartById() to fire less events

There is no point in firing this event when noting changed.
This should reduce flickering and some of the issues described
in I97d77f4.

Change-Id: I7c387889a4a33dac5053cec11a0641d358020b56
---
 .../ve.ui.MWTransclusionOutlineContainerWidget.js     | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/modules/ve-mw/ui/widgets/ve.ui.MWTransclusionOutlineContainerWidget.js b/modules/ve-mw/ui/widgets/ve.ui.MWTransclusionOutlineContainerWidget.js
index 6cef1f1071..9e7d32384e 100644
--- a/modules/ve-mw/ui/widgets/ve.ui.MWTransclusionOutlineContainerWidget.js
+++ b/modules/ve-mw/ui/widgets/ve.ui.MWTransclusionOutlineContainerWidget.js
@@ -153,10 +153,17 @@ ve.ui.MWTransclusionOutlineContainerWidget.prototype.addPartWidget = function (
  *  parameter ids like "part_1/param1".
  */
 ve.ui.MWTransclusionOutlineContainerWidget.prototype.selectPartById = function ( partId ) {
+	var changed = false;
 	for ( var id in this.partWidgets ) {
-		this.partWidgets[ id ].setSelected( id === partId );
+		var selected = id === partId;
+		if ( this.partWidgets[ id ].isSelected() !== selected ) {
+			this.partWidgets[ id ].setSelected( selected );
+			changed = true;
+		}
+	}
+	if ( changed ) {
+		this.emit( 'updateOutlineControlButtons', partId );
 	}
-	this.emit( 'updateOutlineControlButtons', partId );
 };
 
 /**