如何在不按键的情况下使用python更新/重绘GTK控件（GTKLabel）？
我有一些代码，想要更新一个GTK标签元素。我这里提供了两个文件：一个是界面文件，另一个是Python文件。
界面文件：
<glade-interface>
<widget class="GtkWindow" id="ApplicationFrame">
<property name="width_request">320</property>
<property name="height_request">240</property>
<property name="visible">True</property>
<property name="events">GDK_KEY_PRESS_MASK</property>
<property name="title" translatable="yes">Simple</property>
<property name="resizable">False</property>
<property name="window_position">center-always</property>
<property name="default_width">320</property>
<property name="default_height">240</property>
<property name="decorated">False</property>
<property name="gravity">center</property>
<child>
<widget class="GtkFixed" id="layout">
<property name="width_request">320</property>
<property name="height_request">240</property>
<property name="visible">True</property>
<child>
<widget class="GtkLabel" id="l1">
<property name="width_request">320</property>
<property name="height_request">40</property>
<property name="visible">True</property>
<property name="xalign">0</property>
<property name="label" translatable="yes">l1</property>
</widget>
<packing>
<property name="y">43</property>
</packing>
</child>
</widget>
</child>
</widget>
</glade-interface>
Python文件：
import os
from time import sleep as wait
import gtk as gtk
import gtk.glade as glade
import gobject
class Application(object):
def __init__ (self):
self.glade = glade.XML("simple.ui")
self.setup_ui()
def setup_ui (self):
self.window = self.glade.get_widget("ApplicationFrame")
self.l1 = self.glade.get_widget("l1")
self.names = {'l1' : self.l1}
self.all = [self.l1]
gobject.timeout_add(1000,self.display_me)
gobject.timeout_add(100,self.do_something_that_takes_a_while)
self.window.add_events(gtk.gdk.KEY_PRESS_MASK)
self.window.connect("key-press-event", self.handler)
self.window.connect("delete_event", self.delete_event)
self.window.connect("destroy", self.destroy)
self.window.show()
def get_signal (self,widget,event):
keyname = gtk.gdk.keyval_name(event.keyval)
ctrl = event.state & gtk.gdk.CONTROL_MASK
alt = event.state & gtk.gdk.MOD1_MASK
shift = event.state & gtk.gdk.SHIFT_MASK
name = []
if ctrl and keyname not in ["Control_L","Control_R"]:
name.append("CTRL")
if alt and keyname not in ["Alt_L","Alt_R"]:
name.append("ALT")
if shift and keyname not in ["Shift_L","Shift_R"]:
name.append("SHIFT")
name.append(keyname)
name = "+".join(name)
return name
def handler (self,widget,event):
name = self.get_signal(widget,event)
if name.lower() in ['ctrl+x','ctrl+c','alt+q']:
self.destroy()
def main(self):
gtk.main()
def delete_event (self,widget=None,event=None,data=None):
return False
def destroy (self,widget=None,data=None):
gtk.main_quit()
def get (self,item):
if isinstance(item, str):
if item in self.names:
item = self.names[item]
retval = None
if hasattr(item,"text"):
retval = item.text()
elif hasattr(item,"get_label"):
retval = item.get_label()
return retval
def set (self,item,text='',font=None):
print 'Setting...'
if isinstance(item, str):
if item in self.names:
item = self.names[item]
retval = None
if font == None and hasattr(self,"page") and hasattr(self.page,"NORMAL_FONT"):
font = self.page.NORMAL_FONT
if hasattr(item,"setText"):
retval = item.setText(text)
elif font == None:
if hasattr(item,'set_text'):
retval = item.set_text(text)
elif hasattr(item,"set_label"):
retval = item.set_label(text)
if hasattr(item,"modify_font") and font != None:
item.modify_font(font)
item.queue_draw()
self.try_to_update(item)
print 'done'
return retval
def try_to_update (self,item):
"""
do something here to update the visual screen????
"""
print str(self)
def do_something_that_takes_a_while (self):
timeout = 15
while timeout != 0:
self.set('l1','%s' % timeout)
wait(1)
timeout -= 1
print timeout
return 1
def clean (self):
if item != None:
self.set(item,empty_text)
else:
if hasattr(self,'all'):
for item in self.all:
self.set(item)
def display_me (self):
print str(self)
return True
def __str__ (self):
space = 25
value = '%'+str(space)+'s'
lines = ['\n','-'*79]
if hasattr(self,'all'):
line = []
for obj in self.all:
obj_value = self.get(obj)
line.append(value % obj_value if obj_value != None else '')
#line.append(value % ' ')
lines.append(''.join(line))
lines.append('-'*79)
return '\n'.join(lines)
if __name__ == "__main__":
from time import sleep as wait
SEC = 1
app = Application()
app.main()
这应该很简单，但我完全不知道自己哪里出错了。元素l1没有正确更新。我觉得在try_to_update这个函数里是我需要更新界面的地方，但我不知道该调用哪个函数。有人能帮帮我吗？
提前谢谢大家！
2 个回答
2
在这段代码中，有一个情况是，当 do_something_that_takes_a_while 这个方法在运行的时候，其他的事件就不会被处理了。解决这个问题的一种方法是在这个方法的某个地方强制处理事件：
--- code.py 2011-12-05 10:32:53.000000000 +0100
+++ code.py.bak 2011-12-05 10:27:22.000000000 +0100
@@ -95,8 +95,6 @@
timeout = 15
while timeout != 0:
self.set('l1','%s' % timeout)
- while gtk.events_pending():
- gtk.main_iteration()
wait(1)
timeout -= 1
print timeout
11
你需要使用小部件的 queue_draw 函数：
这个
queue_draw_area()方法会让小部件的某个矩形区域失效，也就是说它会标记这个区域需要重新绘制。它是通过调用小部件窗口的gtk.gdk.Window.invalidate_rect()方法来实现的，包括所有子窗口。
不过，既然你已经在你的 set 方法里做了这件事，我猜可能是因为
if hasattr(item,'show')
这个检查阻止了项目的更新。另一个检查方法是对整个窗口调用 queue_draw 函数，看看这样是否能更新内容。
另外，你也可以强制处理那些排队的事件，方法如下：
while gtk.events_pending():
gtk.main_iteration_do(True)