From: Scott Kostyshak <skostysh@lyx.org>
Date: Fri, 29 Jul 2016 17:06:49 +0000 (-0400)
Subject: Improve implementation of TabWorkArea::posIsTab()
X-Git-Tag: 2.3.0alpha1~1214
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=badb0bb96cc22c64210d140643fae521a78c6fdc;p=features.git

Improve implementation of TabWorkArea::posIsTab()

The Qt documentation states that tabAt() returns -1 if the position
is not over a tab. This behavior has been consistent since Qt 4.3
[1]. This commit's improvement likely makes the code faster in two
ways:

(1) we do not need to loop through potentially all tabs
(2) we only need to look up the tab index corresponding with one
position

posIsTab() is not currently used intensively so no practical gain in
speed is achieved, but it protects against future use.

[1] https://doc.qt.io/archives/4.3/qtabbar.html#tabAt
---

diff --git a/src/frontends/qt4/GuiWorkArea.cpp b/src/frontends/qt4/GuiWorkArea.cpp
index b9e5e8ec87..9223964e42 100644
--- a/src/frontends/qt4/GuiWorkArea.cpp
+++ b/src/frontends/qt4/GuiWorkArea.cpp
@@ -1650,10 +1650,8 @@ void TabWorkArea::paintEvent(QPaintEvent * event)
 
 bool TabWorkArea::posIsTab(QPoint position)
 {
-	for (int i = 0; i < count(); ++i)
-		if (tabBar()->tabRect(i).contains(position))
-			return true;
-	return false;
+	// tabAt returns -1 if tab does not covers position
+	return tabBar()->tabAt(position) > -1;
 }