From 817c9634e89be79c5ca4e08ce48c1eb1dd173f46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johannes=20Sch=C3=B6nberger?= <jschoenberger@demuc.de>
Date: Wed, 29 May 2013 20:36:08 +0200
Subject: [PATCH] Fix setting of QT_API environment variable

---
 skimage/viewer/qt/__init__.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/skimage/viewer/qt/__init__.py b/skimage/viewer/qt/__init__.py
index c816a172..8e7ab939 100644
--- a/skimage/viewer/qt/__init__.py
+++ b/skimage/viewer/qt/__init__.py
@@ -16,4 +16,7 @@ if qt_api is None:
             # Note that we don't want to raise an error because that would
             # cause the TravisCI build to fail.
             warnings.warn("Could not import PyQt4: ImageViewer not available!")
+
+
+if qt_api is not None:
     os.environ['QT_API'] = qt_api