App crashed when no upcoming events

When in calendar no upcoming events our application crashed

Getting the upcoming 10 events
 Traceback (most recent call last):
   File "shellper/ui/main.py", line 198, in <module>
     ShellperApp().run()
   File "/usr/lib/python2.7/dist-packages/kivy/app.py", line 577, in run
     root = self.build()
   File "shellper/ui/main.py", line 183, in build
     self.tb_panel.default_tab_content = self.show_event_layer()
   File "shellper/ui/main.py", line 83, in show_event_layer
     event = label.Label(text=event[0]+' '+event[1],
 IndexError: string index out of range