From 1f203a10f9fa30910ebf9cf286a8c064bf45c16e Mon Sep 17 00:00:00 2001
From: Tobias Doerffel <tobias.doerffel@gmail.com>
Date: Tue, 7 Jan 2014 23:49:07 +0100
Subject: [PATCH] Widgets/Knob: only restore journalling state on release of
 left mouse button

Do not try to restore the journalling state of the underlying model when
releasing e.g the right mouse button as this causes a crash otherwise.
---
 src/gui/widgets/knob.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/gui/widgets/knob.cpp b/src/gui/widgets/knob.cpp
index 9f6840349..333925106 100644
--- a/src/gui/widgets/knob.cpp
+++ b/src/gui/widgets/knob.cpp
@@ -488,9 +488,16 @@ void knob::mouseMoveEvent( QMouseEvent * _me )
 
 
 
-void knob::mouseReleaseEvent( QMouseEvent * /* _me*/ )
+void knob::mouseReleaseEvent( QMouseEvent* event )
 {
-	model()->restoreJournallingState();
+	if( event && event->button() == Qt::LeftButton )
+	{
+		AutomatableModel *thisModel = model();
+		if( thisModel )
+		{
+			thisModel->restoreJournallingState();
+		}
+	}
 
 	m_buttonPressed = false;