how to make python socket server work with the app.MainLoop() in wxpython?

Hi everyone,
I am using a python socket server to collect data from a socket
client and then control a image location ( wxpython) with the data,
i.e. moving the image around in the wxpython frame.
But the "app.MainLoop()" in wxpython looks like conflicting with
the "while 1:" in socket server. After I commented the
"app.MainLoop()", everything is working except two things:
1. if I click anywhere on the screen with the mouse, the image is
gong and only the empty frame( or panel) is left.
2. if I don't touch anything, the image is being moved around but
the previous images are left behind in the panel.
I guess that may be caused by "app.MainLoop()" commented.
Anybody knows how to make the two things work together? I really
appreciate your help.
My sample code is modified based on the wxpython demo: image.py.
socket client is also attached for your reference.

Ouyang

################ socket server with wxpython ##############

from Main import opj
import wx,string
class MMCS(wx.Frame):
def __init__(self):
self.bmp = wx.Image(opj('bitmaps/image.bmp'),
wx.BITMAP_TYPE_BMP)
self.bmp.SetMask(True)
wx.Frame.__init__(self, parent=None, title='monitoring system',
size=(500,600))
self.panel = wx.Panel(self,-1)

def monitor(self,x,y,angle):
bmp = self.bmp.Rotate(angle, (x,y), True,None)
bmp = bmp.ConvertToBitmap()

wx.StaticBitmap(self.panel, -1, bmp, (x, y), (bmp.GetWidth(),
bmp.GetHeight()))
del bmp

app = wx.PySimpleApp()
frame = MMCS()
frame.Show()
frame.monitor(50,10,0.0)
#app.MainLoop()

# Server program
from socket import *
# Set the socket parameters
host = "192.168.0.2"
port = 21567
buf = 1024
addr = (host,port)

# Create socket and bind to address
UDPSock = socket(AF_INET,SOCK_DGRAM)
UDPSock.bind(addr)

# Receive messages
while 1:
data,addr = UDPSock.recvfrom(buf)
if not data:
print "Client has exited!"
break
else:
print "\nReceived message '", data,"'"
d = string.split(data, '-')

frame.monitor(string.atoi(d[0]),string.atoi(d[1]),string.atof(d[2]))
if data == 'END':
print "end of moving the ship"

# Close socket
UDPSock.close()

############# socket client ######################>
rom socket import *
import time

# Set the socket parameters
host = "192.168.0.2"
port = 21567
buf = 1024
addr = (host,port)

# Create socket
UDPSock = socket(AF_INET,SOCK_DGRAM)
def_msg = "===Enter message to send to server===";
print "\n",def_msg

# Send messages
while (1):
for i in range(100):
time.sleep(1)
data = "50-100-%s"%(0.1*i)
if(UDPSock.sendto(data,addr)):
print "Sending message '",data,"'....."
# Close socket
UDPSock.close()

re: how to make python socket server work with the app.MainLoop() in wxpython?

zxo102 wrote:

If you get rid of app.MaiLoop(), you basically get rid of all GUI events.
You need to have you server in a separate thread.

Philippe

re: how to make python socket server work with the app.MainLoop() in wxpython?

Philippe Martin wrote:
PS:

http://wiki.wxpython.org/index.cgi/LongRunningTasks

re: how to make python socket server work with the app.MainLoop() in wxpython?

On 2006-07-30, Philippe Martin <pmartin@snakecard.comwrote:
Isn't there any way to use wxWidgets socket callbacks in wxPython?

--
Grant Edwards grante Yow! I'm wearing PAMPERS!!
at
visi.com

re: how to make python socket server work with the app.MainLoop() in wxpython?

Philippe,

Thanks a lot. I got the idea. Let me try it.

Ouyang

Philippe Martin 写道：

re: how to make python socket server work with the app.MainLoop() in wxpython?

Philippe Martin wrote:
And here's an important bit from the wxWindows doc:

For communication between secondary threads and the main thread,
you may use wxEvtHandler::AddPendingEvent or its short version
wxPostEvent. These functions have thread safe implementation
[...]
<http://www.wxwindows.org/manuals/2.6.3/wx_wxthreadoverview.html>

Calling various wxWindows functions from threads other than the
one that runs the GUI, can cause a crash. Use only those that the
authoritative documentation states to be thread-safe, such as
wxPostEvent. The Wiki page that Pilippe cited says that
wxCallAfter uses wxPostEvent internally, so it should also be
thread-safe. I still wouldn't use it; internals are subject to
change.


--
--Bryan

re: how to make python socket server work with the app.MainLoop() in wxpython?

Grant Edwards wrote:
If I understand correctly, I guess you can send an event to the main thread
to tell it there was data received.

Regards,

Philippe

re: how to make python socket server work with the app.MainLoop() in wxpython?

I think you should use thread.
I just write a similar program using thread. It works well
You can try it, good luck!

re: how to make python socket server work with the app.MainLoop() in wxpython?

Philippe,

I just wrote the code following the example you provided. The image
location can be controlled with the data from socket client. But only
one thing confuse me. When the image keeps moving to a new location,
the image at a "old" location is not deleted and is left behind in the
frame. Do you know what is going on with it? The location of image is
processed in "def OnResult(self,event):" and is initialized in "def
__init__(self, parent, id):" of "class MainFrame" ( See the code
attached).

Thanks a lot.

ouyang

##################################################
import time
from threading import *
import wx, string

from socket import *
from Main import opj

host = "192.168.0.2"
port = 21567
buf = 1024
addr = (host,port)
UDPSock = socket(AF_INET,SOCK_DGRAM)
UDPSock.bind(addr)

# Button definitions
ID_START = wx.NewId()
ID_STOP = wx.NewId()

# Define notification event for thread completion
EVT_RESULT_ID = wx.NewId()

def EVT_RESULT(win, func):
"""Define Result Event."""
win.Connect(-1, -1, EVT_RESULT_ID, func)

class ResultEvent(wx.PyEvent):
"""Simple event to carry arbitrary result data."""
def __init__(self, data):
"""Init Result Event."""
wx.PyEvent.__init__(self)
self.SetEventType(EVT_RESULT_ID)
d = string.split(data,'-')
self.data =
[string.atoi(d[0]),string.atoi(d[1]),string.atof(d[2])]



# Thread class that executes processing
class WorkerThread(Thread):
"""Worker Thread Class."""
def __init__(self, notify_window):
"""Init Worker Thread Class."""
Thread.__init__(self)
self._notify_window = notify_window
self._want_abort = 0


# This starts the thread running on creation, but you could
# also make the GUI thread responsible for calling this
self.start()

def run(self):
"""Run Worker Thread."""
# This is the code executing in the new thread. Simulation of
# a long process (well, 10s here) as a simple loop - you will
# need to structure your processing so that you periodically
# peek at the abort variable


while 1:
if self._want_abort:
wx.PostEvent(self._notify_window, ResultEvent(None))
#return
break
else:
data,addr = UDPSock.recvfrom(buf)
if not data:
print "Client has exited!"
break
else:
print "\nReceived message '", data,"'"
wx.PostEvent(self._notify_window, ResultEvent(data))

# Close socket
UDPSock.close()


def abort(self):
"""abort worker thread."""
# Method for use by main thread to signal an abort
self._want_abort = 1

# GUI Frame class that spins off the worker thread
class MainFrame(wx.Frame):
"""Class MainFrame."""
def __init__(self, parent, id):
"""Create the MainFrame."""
wx.Frame.__init__(self, parent,id, title='monitoring system',
size=(500,600))
self.panel = wx.Panel(self,-1,(0,0),(500,600))

self.bmp = wx.Image(opj('bitmaps/image.bmp'), wx.BITMAP_TYPE_BMP)
self.bmp.SetMask(True)

# Dumb sample frame with two buttons
wx.Button(self.panel, ID_START, 'Start', pos=(0,0))
wx.Button(self.panel, ID_STOP, 'Stop', pos=(0,50))
self.status = wx.StaticText(self.panel, -1, '', pos=(0,100))

x = 50
y = 150
angle = 1.23
bmp = self.bmp.Rotate(angle, (x,y), True,None)
bmp = bmp.ConvertToBitmap()
wx.StaticBitmap(self.panel, -1, bmp, (x, y), (bmp.GetWidth(),
bmp.GetHeight()))

self.Bind(wx.EVT_BUTTON, self.OnStart, id=ID_START)
self.Bind(wx.EVT_BUTTON, self.OnStop, id=ID_STOP)

# Set up event handler for any worker thread results
EVT_RESULT(self,self.OnResult)

# And indicate we don't have a worker thread yet
self.worker = None

def OnStart(self, event):
"""Start Computation."""
# Trigger the worker thread unless it's already busy
if not self.worker:
self.status.SetLabel('Starting computation')
self.worker = WorkerThread(self)

def OnStop(self, event):
"""Stop Computation."""
# Flag the worker thread to stop if running
if self.worker:
self.status.SetLabel('Trying to abort computation')
self.worker.abort()

def OnResult(self, event):
"""Show Result status."""
if event.data is None:
# Thread aborted (using our convention of None return)
self.status.SetLabel('Computation aborted')
else:
# Process results here
self.status.SetLabel('Computation Result: %s-%s-%s' %
(event.data[0], event.data[1],event.data[2]))
angle = event.data[2]
x = event.data[0]
y = event.data[1]
bmp = self.bmp.Rotate(angle, (x,y), True,None)
bmp = bmp.ConvertToBitmap()
wx.StaticBitmap(self.panel, -1, bmp, (x, y),
(bmp.GetWidth(), bmp.GetHeight()))
# In either event, the worker is done
self.worker = None

class MainApp(wx.App):
"""Class Main App."""
def OnInit(self):
"""Init Main App."""
self.frame = MainFrame(None, -1)
self.frame.Show(True)
self.SetTopWindow(self.frame)
return True

if __name__ == '__main__':
app = MainApp(0)
app.MainLoop()

################################################## ########



Philippe Martin 写道：

re: how to make python socket server work with the app.MainLoop() in wxpython?

Dennis:

Thanks for your message. Let me try the double-buffer-operation.

Ouyang
Dennis Lee Bieber wrote: