From d3392418c458a2d9e02f3dcc83978e2f1e11e98b Mon Sep 17 00:00:00 2001
From: =?utf8?q?Peter=20K=C3=BCmmel?= <syntheticpp@gmx.net>
Date: Thu, 21 Oct 2010 21:29:08 +0000
Subject: [PATCH] use QWaitCondition instead of QEventLoop for waiting on GUI
 thread-call finished, it's cheaper

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@35763 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/frontends/qt4/InGuiThread.cpp | 16 ++++++++--------
 src/frontends/qt4/InGuiThread.h   |  8 ++++++--
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/src/frontends/qt4/InGuiThread.cpp b/src/frontends/qt4/InGuiThread.cpp
index b9332997f1..ff53f9d0e9 100644
--- a/src/frontends/qt4/InGuiThread.cpp
+++ b/src/frontends/qt4/InGuiThread.cpp
@@ -15,6 +15,8 @@
 #include <QThread>
 #include <QEventLoop>
 #include <QApplication>
+#include <QMutexLocker>
+
 
 namespace lyx {
 namespace frontend {
@@ -32,13 +34,11 @@ void IntoGuiThreadMover::callInGuiThread()
 		synchronousFunctionCall();
 	} else {
 		moveToThread(gui_thread);
-		connect(this, SIGNAL(triggerCall()), this, SLOT(doFunctionCall()),
-		        Qt::QueuedConnection);
-		// TODO try with condition, it's maybe cheaper
-		QEventLoop loop;
-		connect(this, SIGNAL(called()), &loop, SLOT(quit()));
-		Q_EMIT triggerCall();
-		loop.exec();
+		connect(this, SIGNAL(triggerFunctionCall()), 
+		        this, SLOT(doFunctionCall()), Qt::QueuedConnection);
+		QMutexLocker lock(&sync_mutex_);
+		Q_EMIT triggerFunctionCall();
+		condition_.wait(&sync_mutex_);
 	}
 }
 
@@ -46,7 +46,7 @@ void IntoGuiThreadMover::callInGuiThread()
 void IntoGuiThreadMover::doFunctionCall()
 {
 	synchronousFunctionCall();
-	Q_EMIT called();
+	condition_.wakeOne();
 }
 
 
diff --git a/src/frontends/qt4/InGuiThread.h b/src/frontends/qt4/InGuiThread.h
index 6d3b778a04..73a9d4ccd6 100644
--- a/src/frontends/qt4/InGuiThread.h
+++ b/src/frontends/qt4/InGuiThread.h
@@ -12,7 +12,9 @@
 #ifndef INGUITHREAD_H
 #define INGUITHREAD_H
 
+#include <QMutex>
 #include <QObject>
+#include <QWaitCondition>
 
 #include "support/bind.h"
 #include "support/functional.h"
@@ -32,14 +34,16 @@ protected:
 	void callInGuiThread();
 
 Q_SIGNALS:
-	void triggerCall();
-	void called();
+	void triggerFunctionCall();
 
 private Q_SLOTS:
 	void doFunctionCall();
 
 private:
 	virtual void synchronousFunctionCall() = 0;
+
+	QWaitCondition condition_;
+	QMutex sync_mutex_;
 };
 
 
-- 
2.39.2