beremiz

fix Traceback if search icon on library panel is clicked, when no
category/item is selected in the library.

The problem is here, that if nothing is selected method GetSelection()
returns root item, that doesn't have any python data associated with it.
This issue seems to be wx3.0 specified, because it doesn't exist
with wx2.8 on Windows.
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<Python xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.w3.org/2001/XMLSchema" xsi:schemaLocation="py_ext_xsd.xsd">
<![CDATA[import threading, time
MyT = None
Stop = False
def StartLog():
global MyT
MyT=threading.Thread(target = DoLog)
MyT.start()
def DoLog():
global Stop
while not Stop:
PLCObject.LogMessage("Python side Logging (PLC is %s)"%PLCObject.PLCStatus)
time.sleep(0.3)
def StopLog():
global MyT,Stop
Stop=True
_runtime_init.append(StartLog)
_runtime_cleanup.append(StopLog)
]]>
</Python>