From a48a3776be264b39b723bae1e7c4f47669f3135b Mon Sep 17 00:00:00 2001
From: Pol Welter <welterp@phys.ethz.ch>
Date: Fri, 1 Jun 2018 10:31:47 +0200
Subject: [PATCH] Fix issue #697

---
 pyqtgraph/widgets/SpinBox.py | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/pyqtgraph/widgets/SpinBox.py b/pyqtgraph/widgets/SpinBox.py
index ea59bf31..496ea37a 100644
--- a/pyqtgraph/widgets/SpinBox.py
+++ b/pyqtgraph/widgets/SpinBox.py
@@ -509,8 +509,14 @@ class SpinBox(QtGui.QAbstractSpinBox):
     def fixup(self, strn):
         # fixup is called when the spinbox loses focus with an invalid or intermediate string
         self.updateText()
-        strn.clear()
-        strn.append(self.lineEdit().text())
+
+        # support both PyQt APIs (for Python 2 and 3 respectively)
+        # http://pyqt.sourceforge.net/Docs/PyQt4/python_v3.html#qvalidator
+        try:
+            strn.clear()
+            strn.append(self.lineEdit().text())
+        except AttributeError:
+            return self.lineEdit().text()
 
     def interpret(self):
         """Return value of text or False if text is invalid."""