Here is a working version of a single Glade (xml) file referencing 2 python modules for it's signal handlers. The "magic" function is mainly a simplification of the load_handlers() function in gscreen.py.
The Glade file:
Code:
<?xml version="1.0" encoding="UTF-8"?>
<interface>
<requires lib="gtk+" version="2.18"/>
<!-- interface-naming-policy toplevel-contextual -->
<object class="GtkWindow" id="window1">
<property name="can_focus">False</property>
<signal name="destroy" handler="onDestroy" swapped="no"/>
<child>
<object class="GtkHBox" id="hbox1">
<property name="visible">True</property>
<property name="can_focus">False</property>
<child>
<object class="GtkButton" id="button1">
<property name="label" translatable="yes">button w. local handler</property>
<property name="visible">True</property>
<property name="can_focus">True</property>
<property name="receives_default">True</property>
<signal name="pressed" handler="onButton1Pressed" swapped="no"/>
</object>
<packing>
<property name="expand">True</property>
<property name="fill">True</property>
<property name="position">0</property>
</packing>
</child>
<child>
<object class="GtkButton" id="button2">
<property name="label" translatable="yes">button w. external handler</property>
<property name="visible">True</property>
<property name="can_focus">True</property>
<property name="receives_default">True</property>
<signal name="pressed" handler="onButton2Pressed" swapped="no"/>
</object>
<packing>
<property name="expand">True</property>
<property name="fill">True</property>
<property name="position">1</property>
</packing>
</child>
<child>
<object class="GtkLabel" id="label1">
<property name="visible">True</property>
<property name="can_focus">False</property>
<property name="label" translatable="yes">label</property>
</object>
<packing>
<property name="expand">True</property>
<property name="fill">True</property>
<property name="position">2</property>
</packing>
</child>
<child>
<object class="GtkLabel" id="label2">
<property name="visible">True</property>
<property name="can_focus">False</property>
<property name="label" translatable="yes">label</property>
</object>
<packing>
<property name="expand">True</property>
<property name="fill">True</property>
<property name="position">3</property>
</packing>
</child>
</object>
</child>
</object>
</interface>
The "main" python file:
Code:
#!/usr/bin/env python
import gtk
import external_module
# trampoline and load_handlers are used for custom displays
# (Copied from gscreen.py. I don't know how it works but seems necessary. Guru help?)
#
class Trampoline(object):
def __init__(self,methods):
self.methods = methods
print("Trampoline instance")
def __call__(self, *a, **kw):
for m in self.methods:
m(*a, **kw)
class Handler:
def onDestroy(self, *args):
print("quit app")
gtk.main_quit()
def onButton1Pressed(self, button):
print("Button1 Pressed")
self.builder.get_object("label1").set_text("Button 1 pressed")
# This function scans the given class object for signal handlers
# and adds them to a (class-global) dictionary, which we'll pass to
# connect_signals().
#
# This allows us to add signal handlers from "self" as well as from classes in external python modules
#
def _load_handlers(self, object):
#print("Registering handlers in object %s" % (object))
#for object in objects:
if isinstance(object, dict):
methods = dict.items()
else:
methods = map(lambda n: (n, getattr(object, n, None)), dir(object))
for method,f in methods:
if method.startswith('_'):
continue
if callable(f):
print("Registering callback %s" % (method))
if method in self.handlers:
# Note, I would sometimes get an error here but it would occur at the end of the iteration process.
# I found that I could replace the following line with a simple print warning.
self.handlers[method].append(f)
else:
self.handlers[method] = [f]
# Wrap lists in Trampoline, unwrap single functions
# (Copied from gscreen.py. I don't know how it or the Trampoline class works
# but it seems necessary.) Python guru help?
for n,v in list(self.handlers.items()):
try:
if len(v) == 1:
self.handlers[n] = v[0]
else:
self.handlers[n] = Trampoline(v)
except:
continue
# I kept getting the error, "no len(v) for type instancemethod" but that was always after the iteration was complete
# so I'm simply trapping and ignoring the error. (Guru help needed...)
def __init__(self):
self.builder = gtk.Builder()
self.builder.add_from_file("multi-module-test.glade")
# Get an instance of the external python module
self.xmod = external_module.externalHandler(self.builder)
# Create a dictionary to hold the signal-handler pairs
self.handlers = {}
# Call the magic function to load signal handlers from this and any other class module
#
self._load_handlers(self.xmod)
self._load_handlers(self)
#self.handlers = {"onButton1Pressed": self.onButton1Pressed, "onDestroy": self.onDestroy, "onButton2Pressed": self.xmod.onButton2Pressed}
self.builder.connect_signals(self.handlers)
self.window = self.builder.get_object("window1")
self.window.show_all()
try:
app = Handler()
except KeyboardInterrupt:
sys.exit(0)
gtk.main()
The "external" python module:
Code:
#!/usr/bin/env python
import gtk
class externalHandler:
def onButton2Pressed(self, button):
self.builder.get_object("label2").set_text("Button 2 pressed")
print("Button2 Pressed")
def __init__(self, builder):
self.builder = builder
There are a few areas of uncertainty but it basically works. I'm certainly open to suggestions/clarifications to improve the code.
