Fixed ViewBox error when accessing zoom history before having zoomed.

2014-05-18 19:14:57 -04:00 · 2014-05-18 19:14:57 -04:00 · 279ad1bee0
commit 279ad1bee0
parent ab411012f8
1 changed files with 2 additions and 0 deletions
--- a/pyqtgraph/graphicsItems/ViewBox/ViewBox.py
+++ b/pyqtgraph/graphicsItems/ViewBox/ViewBox.py
@ -1312,6 +1312,8 @@ class ViewBox(GraphicsWidget):
            ev.ignore()

    def scaleHistory(self, d):
+        if len(self.axHistory) == 0:
+            return
        ptr = max(0, min(len(self.axHistory)-1, self.axHistoryPointer+d))
        if ptr != self.axHistoryPointer:
            self.axHistoryPointer = ptr