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Re: Multitasking and GTK with python

Quote:

Originally Posted by McLightning (Post 593767)

class gui(threading.Thread):
__def __init__(self):
____self.a=0
____.......
____self.entrybox=self.wTree.get_widget('entry2')
____threading.Thread.__init__(self)
__def run(self):
____while 1:
______print self.a
______self.entrybox.set_text(a)
______self.a=self.a+1

gui().start()
gtk.main()

it is not working this way either

Can you please post full code, or add as an attachment if it's too long?

Re: Multitasking and GTK with python

Don't forget to initialize threads with gobject or else (I suspect) it holds on to the GIL while mainloop is processing and doesn't allowing other threads to run.

I've been using

Code:

gtk.gdk.threads_init()

Also if you ever access GTK from outside of your UI thread, you need to be sure to grab the locks. I use the following helper

Code:

@contextlib.contextmanager

def gtk_lock():

        gtk.gdk.threads_enter()

        try:

                yield

        finally:

                gtk.gdk.threads_leave()

Code:

with gtk_lock():

        # do stuff

If you want an example of a threaded PyGTK program, checkout Dialcentral's source
https://garage.maemo.org/scm/?group_id=657

You can also queue tasks to run in the UI thread from your worker thread using idle_add. I use the following helper

Code:

def async(func):

        """

        Make a function mainloop friendly. the function will be called at the

        next mainloop idle state.

        """



        @functools.wraps(func)

        def new_function(*args, **kwargs):



                def async_function():

                        func(*args, **kwargs)

                        return False



                gobject.idle_add(async_function)



        return new_function

For a more advanced PyGTK threading example than Dialcentral I recommend The One Ring. Though it isn't GTK but DBus based, the principles are the same and the helpers I use in go_utils will work in both.
https://garage.maemo.org/scm/?group_id=1078

Re: Multitasking and GTK with python

Code:

import pygtk

import gtk

import hildon

import gtk.glade

from bluetooth import *

import time,threading

class gui(threading.Thread):

  def gon(self,data=None):

    data=self.got.get_text()

    print data

    if len(data)!=0:

      self.sock.send(data)



  def __init__(self):

    self.a=0

    self.program = hildon.Program()

    self.program.__init__()

    self.window = hildon.Window()

    self.program.add_window(self.window)

    self.window.connect("destroy", gtk.main_quit)

    self.glade_file = "sck.glade"

    self.wTree = gtk.glade.XML(self.glade_file)

    self.got = self.wTree.get_widget("entry1") 

    self.al = self.wTree.get_widget("entry2")

    btn = self.wTree.get_widget("button1")

    signals={'clicked':self.send}

    self.wTree.signal_autoconnect(signals)

    self.fx=self.wTree.get_widget("notebook1")        

    self.reparent_loc(self.fx, self.window)

    self.gtkWindow = self.wTree.get_widget("window1")

    self.gtkWindow.destroy()

    self.window.show()

    print 'connecting'

    self.sock=BluetoothSocket(RFCOMM)

    self.sock.connect(('00:1F:00:B5:3A:45',5))

    print "connected."



    threading.Thread.__init__(self)

  def run(self):

    while True:

      self.a=self.a+1

      self.got.set_text(self.a)

      print a

  def reparent_loc(self, widget, newParent):

    widget.reparent(newParent)



gui().start()

gtk.main()

this is the full code

Re: Multitasking and GTK with python

Also, if you use threads with gtk, you need to call
gtk.gdk.threads_init().

pygtk (binding for python and gtk) holds the GIL (which is kind of a global lock for the process) unless threads_init() is called.

Try adding this line in the __init__.

Re: Multitasking and GTK with python

i posted the full code please could you tell me what should i do about it?
edit:
yeaa great it worked
it worked

THANK YOU ALL :d:d

Re: Multitasking and GTK with python

Quote:

Originally Posted by McLightning (Post 593784)

i posted the full code please could you tell me what should i do about it?

I suggested what you should do if you want to use threads for background work, aka write to a file or print to the terminal or doing some calculations, but keep all the GUI updates to the main thread (called 'UI thread').

epage mentioned that as well but also extended this to how to handle the GUI itself from within child-threads (also called 'worker threads'), and suggested an alternative - give the gtk to handle your worker threads while it's available using the add_idle example he attached.

An advice - If it's your first work with treads, you might want to know more about threads in general and threads in python before diving into gtk's way for handling threads.

Re: Multitasking and GTK with python

it is great im very excited it worked after adding gtk.gdk.threads_init()
thank you all for all helps
im really appreciated

Re: Multitasking and GTK with python

Just use gobject.io_add_watch to be notified when there is data to read and spare yourself the ordeal of using threads.

http://faq.pygtk.org/index.py?req=sh...=faq20.016.htp

def handle_data(source, condition):
__data = source.recv(1024)
__if len(data) > 0:
____self.entrybox.set_text(self.entrybox.get_text( ) + data)
____# or maybe just self.entrybox.props.text += data
____#print data
____return True # call me again if something happens
__else: # end of file
____return False # stop calling me

sock=BluetoothSocket(RFCOMM)
#sock.settimeout(15) # ?
sock.connect(('00:1F:00:B5:3A:45',5))
gobject.io_add_watch(sock, gobject.IO_IN, handle_data)

What happens is that your GUI program ALSO watches your socket and should something arrive, it will call "handle_data" which then reads the chunk that arrived (that is fast).
After that, your GUI program resumes. Note that threads didn't enter the picture anywhere (not in the GTK library either).

Re: Multitasking and GTK with python

i made a couple of apps that im using myself
one is for texting over n95 8gb and received text messages via n95 8gb