exemples/python/py_ext_0@py_ext/pyfile.xml
author Edouard Tisserant <edouard.tisserant@gmail.com>
Wed, 05 Oct 2022 16:10:17 +0200
branchwxPython4
changeset 3617 c3aae4c95bc1
parent 3318 aee9e98c856a
child 3814 ab0afe798428
permissions -rw-r--r--
Runtime: work around 1s delay added when using twisted reactor's callLater.

Since wxPython4, using wxReactor from non-main thread was producing
exceptions in wxWidget's C++ code. Then reactor.run() was called from
main thread, and runtime's worker was delegating calls to reactor
with callLater(0, callable).

While this worked perfectly with wxReactor, it did introduce an unexplained
1 second delay to each worker call when using nomal linux reactors
(i.e. without wxPython). As a workaround reactor runs in a thread when using
twisted without wxPython
<?xml version='1.0' encoding='utf-8'?>
<PyFile xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <variables>
    <variable name="SomeVarName" type="DINT" onchange="MyFunc, SomeChange"/>
    <variable name="Grumpf" type="STRING" initial="'mhoo'" onchange="MyFunc, MyOtherFunc"/>
  </variables>
  <globals>
    <xhtml:p><![CDATA[
print "All python PLC globals variables :", PLCGlobalsDesc
print "Current extention name :", __ext_name__

def MyFunc(*args):
    print args

def MyOtherFunc(*args):
    print "other", args

def SomeChange(*args):
    print "count",OnChange.SomeVarName.count
    print "first",OnChange.SomeVarName.first
    print "last",OnChange.SomeVarName.last


]]></xhtml:p>
  </globals>
  <init>
    <xhtml:p><![CDATA[
]]></xhtml:p>
  </init>
  <cleanup>
    <xhtml:p><![CDATA[
]]></xhtml:p>
  </cleanup>
  <start>
    <xhtml:p><![CDATA[
]]></xhtml:p>
  </start>
  <stop>
    <xhtml:p><![CDATA[
]]></xhtml:p>
  </stop>
</PyFile>