1  import hal
 2  import glib
 3  import time
 4  
 5  class HandlerClass:
 6      '''
 7      class with gladevcp callback handlers
 8      '''
 9  
10      def on_button_press(self,widget,data=None):
11          '''
12          a callback method
13          parameters are:
14              the generating object instance, likte a GtkButton instance
15              user data passed if any - this is currently unused but
16              the convention should be retained just in case
17          '''
18          print "on_button_press called"
19          self.nhits += 1
20          self.builder.get_object('hits').set_label("Hits: %d" % (self.nhits))
21  
22      def __init__(self, halcomp,builder,useropts):
23          '''
24          Handler classes are instantiated in the following state:
25          - the widget tree is created, but not yet realized (no toplevel window.show() executed yet)
26          - the halcomp HAL component is set up and the widhget tree's HAL pins have already been added to it
27          - it is safe to add more hal pins because halcomp.ready() has not yet been called at this point.
28  
29          after all handlers are instantiated in command line and get_handlers() order, callbacks will be
30          connected with connect_signals()/signal_autoconnect()
31  
32          The builder may be either of libglade or GtkBuilder type depending on the glade file format.
33          '''
34  
35          self.halcomp = halcomp
36          self.builder = builder
37          self.nhits = 0
38  
39  
40  
41  
42  def get_handlers(halcomp,builder,useropts):
43      '''
44      this function is called by gladevcp at import time (when this module is passed with '-u <modname>.py')
45  
46      return a list of object instances whose methods should be connected as callback handlers
47      any method whose name does not begin with an underscore ('_') is a  callback candidate
48  
49      the 'get_handlers' name is reserved - gladevcp expects it, so do not change
50      '''
51      return [HandlerClass(halcomp,builder,useropts)]