Marco Islas Blog

2008 10 08

markuz@islascruz.org (Marco Antonio Islas Cruz) — Wed, 08 Oct 2008 02:13:59 -0500

So, it is time to post again.. this time is to post about christine. Christine as many of you know is a small project of mine, it must be an easy to use and small (and cute) media player, It start as some gstreamer play and then it becomes the music player I use for my every day, no longer rhythmbox nor banshee, wich are fine, but, not for me.

The project is slow, mostly because I code on it when I need something else or just want to fix something that don't like me. Why? because I get almost no feedback. So, if you use christine or, you want to see this project to grow up, please, test it and fill bugs or request features so we can work on it or maybe you want to cooperate with this project in another way, like writing documents, doing artwork or something like that.

The last two weeks GaRaGeD have been working on christine too, on the Pidgin "plugin" which is a nice plugin and I have been doing my work too. This makes me fell good, when you are not the only one in the project it feels better, when you can discuss some point to other project mates and know what would be the better for the average user.

Well, I'm working on the plugin interface and in the last.fm plugin for christine, I already have the authorization part, and then create the configuration dialog for the plugin, this requires me to get familiar with last.fm but, if you already use last.fm and want some feature that you already have in another player, please comment here or on the feature request tracker for the christine project.

On the paid work side, I have been working a lot with Gtk, and reading about the Human Interface Guidelines, have you noted that the GNOME Human Interface Guidelines are quite similar to the Apple Human Interface Guidelines. Well, I hope this helps me to create more intuitive and very usable gtk interfaces.

On the personal side. Cristina and I are really happy, last friday we went to the gynecologist and we see our baby, he is three months right and everything looks right. I have nothing more to say, Im happy!

Just to close this post, if you use mac or compiz, how does looks likeyour desktop right now using the Exposé or the Scale plugin on compiz

Tweeting the song from christine

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sat, 04 Oct 2008 13:03:17 -0500

Tweeting the song from christine, originally uploaded by markuz.

Inspired by GaRaGeD's pidgin "plugin" (christine still doesn't have a plugin API), I wrote my "plugin" to tweet the song on being played on christine.

Asi es la vida de un desarrollador...

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 02 Oct 2008 13:18:36 -0500

Visto en el blog de Kraxbox

About my life

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 26 Sep 2008 02:55:06 -0500

Another post on the blog. I know, I haven't post too regularly these days, this is because I have a lot of work, and my spare time is used to be with cristina and our growing still-in-the-belly baby.

Well, I think you just don't care abot my life, is quite boring for everyone that is not me. Why? just because this is not the blog of some kind of nerdy hacker that do lot of shiny new and amazing stuff, nor the guy that post every single fart that Apple, ubuntu nor Microsoft does.

So, what is about this blog? I think is a way to flush my mind. I wish I have all the time to write more posts, Several times I had Ideas to be written in the blog, but they didn't come to the blog because (again) there is no time.

Anyway, three paragraphs are enough for my complaints. So, what have I done since my last Post? (the christine love, the picture is not..a post) Well, let me see... let me see... Lot of work. I have been working on this project on ICTC, a desktop application using Python and PyGtk.

User interface design is a quite interesting challenge, and more if you need to design input forms, make them look good, being user friendly (mmm, user friendly... If user friendly means scratching the testicles {or your favorite scratch part of the body} of the users. This application in some forms, need to be fully functional without mouse and use only the key pad, which makes the challenge more interesting. Writing a form that makes input validation, key-press-event handling for every widget, looks good, be ultra-easy to use is... is sometimes castrating... (the more if the client want the application in this color: #FF00FF.)

Obviously I don't have to see the application in that color, but I also have to write a color chooser for this application, if I don't, then the client is going to ask me to change the colors after 15 days using the program or when it get almost blind.

Well. This is most of the work I have done, I'm trying to learn how to use django. I love python, and I want to use django (or another python based framework) to write web applications in the future. I have write some applications but nothing really functional by now. One of the first and small projects I want to do is a web page for christine.

And talking about christine, I'm still working on the new version. I'm refactoring modules. And by now is quite usefull. Just commit this night fixes for the bug #2122313 but I need people to test it to check it is working fine. I have also fixed the open remote dialog that wasn't working since I reallocate this methods.

Well, I thinks is enough for today. See you latter.

Update I forgot, If you like the season 1 of The Big Bang Theory you can the download links from Here, those rar files don't have the subtitles, I will post them there too. I have been watching this tv serie and I love it.

Giving love to christine

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 16 Sep 2008 19:56:06 -0500

Giving love to christine, originally uploaded by markuz.

This is my desktop testing some changes I have done to christine in this night. Most of them code cleaning and some harmless optimizations.

Update: I have made a screencast, you can download it

here

Update: Maybe you want to see the full resolution video

HotKeys on Windows using Python

markuz@islascruz.org (Marco Antonio Islas Cruz) — Wed, 10 Sep 2008 01:19:37 -0500

A few weeks ago, I have to write a program in PyGTK that was supposed to be all the time in the background. This application needs to run over Microsoft Windows, and hide in the notification area, wich in Windows is near to the clock.

One of challenges for me in this application is that as it must run in the background there must be a way to raise it, the most easy way to do it is by force the user to click on the small icon in the notification area, but in this case, that was impossible because the computer don't have any mouse, everything is done with the keyboard.

So, I start googling for some way to use hot keys with GTK (PyGtk) in this case, I found that Gtk does have a way to represent the Display wich a way to get to your computer display resources. I just want to grab the keyboard presses and if the right key with the right modifier where pressed then the application arises.

Unfortunely for me, Gtk+ does have a way to do this, but the implementation in PyGTK has a bug where all the display events are ignored, I mean, every time you check of a pending event for the display pygtk will return None, so, no event, no catch, no working code.

Well, in linux you can do this by using the xlib bindings for python, but I have to do this on Windows, so a workmate point me to This url. Wich shows how to register a hot key on windows.

That was easier than I thought!. But, there is a trick... As you can see in this piece of code:

try:
msg = wintypes.MSG ()
while user32.GetMessageA (byref (msg), None, 0, 0) != 0:
if msg.message == win32con.WM_HOTKEY:
action_to_take = HOTKEY_ACTIONS.get (msg.wParam)
if action_to_take:
action_to_take ()

user32.TranslateMessage (byref (msg))
user32.DispatchMessageA (byref (msg))

The method GetMessageA is the one that is listening to the messages in the system, and returns when there is a message. If you use a single threaded program, like... some text bassed application or just a "show something" application, then it will be nice, but, if you use Gtk, where the application's events are handled in the gtk main loop this is useless, why? because this method locks until it receives something, and then let your application work, but, if you have it in a while loop you will never leave that loop and then, your signals will never been emited and your handler will never do their job. Is something similar to the use of sockets. Ha... I forgot, you can't use the while gtk.events_pending(): gtk.main_iteration_do() stuff.. it doesn't work, keep reading if you wanna know why.

So, what can I do for this to work?, well, I thought: A thread, but, there is a problem. Windows documentation says that the hotkey registerd with the method RegisterHotKey will only be catched with GetMessageA if the "register" method and the "get message" are in the same thread.

So, what can I do? Put this on the same thread, and then use a flag to let the rest of your application know that the keys have been pressed, then, raise your application. But, why I can't make a gobject based class that emits a signal when this keys are pressed? Well, you should know that Gtk+ is thread aware, but not thread safe, this means, you cannot use Gtk accross the threads, and this is something inherited from gobject (AFAIK).

Here's the code that will let you register hot keys on windows and make your applications raise when you need them.

#!/usr/bin/env python

import ctypes
import thread
import win32con
import gobject
from ctypes import wintypes

class keyhandler:
def __init__(self):
self.__emit = False
thread.start_new_thread(self.__catchMsgs, tuple())
gobject.timeout_add(5,self.checkEmit)

def checkEmit(self):
if self.__emit:
self.emit('keyhandler-keypress',self,self.__emit)
print 'Emitiendo senial..'
self.__emit = False
return True

def __catchMsgs(self, *args):
byref = ctypes.byref
user32 = ctypes.windll.user32
self.HOTKEYS[1] = {'hotkey' : win32con.VK_F3,'modifiers': win32con.MOD_WIN}
if not user32.RegisterHotKey (None, 1, win32con.MOD_WIN, win32con.VK_F3):
print "Unable to register id", 1
while 1:
try:
msg = wintypes.MSG()
if user32.GetMessageA (byref (msg), None, 0, 0):
if msg.message == win32con.WM_HOTKEY:
if self.HOTKEYS.has_key(msg.wParam):
self.__emit = self.HOTKEYS[msg.wParam]
user32.TranslateMessage (byref (msg))
user32.DispatchMessageA (byref (msg))
except:
pass

Christine folder import

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 09 Sep 2008 16:51:27 -0500

christine, originally uploaded by markuz.

This is christine (trunk) importing a whole folder, about 1321 songs in just 1:07 mins.

Christine using 6Mb

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sun, 17 Aug 2008 23:04:53 -0500

screenshot3.png, originally uploaded by markuz.

This is a screenshot quite surprising for me, this is the gnome-system-monitor saying that christine uses just 6Mb of my RAM. I was looking for memory leaks in one of the applications that I'm currently developing in ICT Consulting, and I found that the memory used by one program, that memory that just belongs to the program is the Writeable memory and that is the memory you should be aware.

I have to say, christine was doing nothing, Just launch it and listen some music, then for one reason that I don't remember, just set it to pause and I get over another task, now, looking at the process table, christine is using more thatn 6 Mb.

btw.. Im using Christine 0.1.6.

WTF! Recursive errors.

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sat, 09 Aug 2008 18:30:15 -0500

wtf !, originally uploaded by markuz.

An internal error ocurred while showing an internal error.

Update:

@shakaran: In Eclipse 3.4, trying to install some components.

Christine in launchpad

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sun, 03 Aug 2008 11:00:41 -0500

As the title says: Christine is now in lauchpad, the code in sourceforge.net si no longer maintained, the reason: I cannot commit my changes to the svn repo, then, I cannot share the newest code.

Christine is now a registered project in Launchpad, well, christine has been a in launchpad for a while but never really use it. So, I will use the launchpad christine account. The bug tracker, the code (and all the good things that launchpad offers) will be hosted here.

As part of the change, christine no longer use Subversion, instead, will use Bazaar, you can get the code using this:

bzr branch lp:christine

Christine love in the night

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 24 Jul 2008 02:03:57 -0500

Christine love in the night, originally uploaded by markuz.

1:47 in the morning. Im still giving some love to christine, that personal proyect that I used to code frequently. Now, it takes some days before I can toch it.

I'm working on the sqlite3 storage layer, This should help me with a more unified data between multiple "sources" that should be renamed as playlists. This will be usefull for many other features, I'm thinkin in some kind of browser.

Anyway, I'm still in the process. I'd like to share the code I have, but SourceForge.net's SVN service is bothering me with a 403 (Forbidden) error that don't let me commit my changes. Now I'm seriously change the project host. What do you recommend?

GNOME 3.0 (Everything with tabs) == Suck!

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sun, 13 Jul 2008 15:22:02 -0500

I believe that GNOME as a project is a very great project, event with the fact that they are reinveing the wheel from time to time (galeon, epiphany => epiphany webkit?). Anyway, I think it's great and as desktop is great too. I use GNOME in my every day and most of the time I'm quite happy, c'mon, there is no desktop environment that have everythin that every user could need.

I love most of the applications that GNOME has as desktop and many others that are not part of the Desktop but integrates well with it. I use such applications because they solve at least one of my problems, being something for my work or just my day to day computer use, and in most of the cases they solve that problem in a very good way, making me feel like I own my computer. But, I also think that they should evolve to be better.

In latest posts on http://planet.gnome.org/ I have seen several posts about some projects that want have tabs everywhere, which for me is ridiculous, Not every application must have tabs. One example is the totem at least not in the way Wouter Bolsterlee is showing it. Another application that I think should not is the calculator. Nautilus is nice for me because it may improve the user's workflow, but does anyone plays two items at the same time?.

Another UGLY example is what Davyd Madeley proposes to the GNOME panel, he may have some point while some people don't know "...what the little grey and blue boxes on their panel are for..." But the users are not stupid, they click them and will know that are they for. And.. a panel with tabs is just UGLY uses more space and useleses (I don't use the workspace switcher applet... is useles at least for me).

I Hope the GNOME developers reconsider where they should or not use tabs in the applications. And if they are going to do that.. Christian Neumair.

Christine importing a folder.

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 26 Jun 2008 23:31:30 -0500

Christine importing a folder., originally uploaded by markuz.

I had worked on christine weeks ago, this week I had no time to give it some love. I have been using this "development" version (I think every version of christine is a development version) for a while.

Christine is faster at the load time, starting in just 4 seconds with at least 1500 items in the list, and the search and sort is quite fast too. But working with something like 6889 items in another 'source' I had make it a bit slow.

I think this is because christine use 3 models in the main list. Yes, three models. One is the main model, the one that holds all the library data. then the filter model and then the sort model. I'll try to make a model that implements in some way the filter and sort to reduce the work.

I notice that when you use a filter or even worse a filter and sort model ever time you select or move your cursor, or do anything with a row this process has to be done for every model you have. I mean, in christine you have to do it three times because of the three models. I think this sucks.

Well, I hope to have the time to write a bit on christine in this week.

What have I done in the last month ??

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 19 Jun 2008 05:41:09 -0500

Well, as many of you know, this site, islascruz.org was "down", and I put down between quotes because wasn't really down, but, almost everybody uses islascruz.org and not islascruz.com, and that's ok. Anyway, islascruz.org is back again and I hope it never fails again.

Now, What have I done in the last month?, well, not blogging . I have been using twitter but I had this need to post on my own site.

I had worked on christine, making it a little more usable, now,it loads in my computer in just a couple of seconds with a track list that is about 2600 rows, It uses a little less memory and I'm trying to make it better. But I'm working in some projects in the work (the paid work) and the idea to be working 8 hours in the office and get to the house to keep working isn't a very nice idea.

Cristina and I get to the movies, we watch The Happening. Many people didn't like it, and I think this is because there is too much talk, too much death and almost no action. But the point in the movie is the message, we are hurting the planet, and we shouldn't. So, after the blablabla and the blood I like it, just by the message. We also watch Indiana Jones, and to be honest, I like it, but is not by far the most awesome movie I have seen.

As part of the "Leave the stress" activities cristina and I are doing, we are doing scented candles. We enjoy doing it, but the hard issue is cleaning the mess we do.

Well, I think I'm gonna leave this post here, my life is not that intersting. You should read somebody else personal posts..

Creating a gtk custom model

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sat, 17 May 2008 10:27:56 -0500

I have been working this week in a new custom model for one of the applications we are developing here at ICT Consulting. We found a problem with many many rows in gtk.ListStore. This is a common problem with Gtk's ListStore and TreeStore. Both are easy to implement and convenient if you are not going to work with too many values. I'm thinking in a couple of thousands. As far as this, the TreeModel is quite usable, but if you use a TreeFilterModel and/or TreeModelSort then you will experience some performance issues.

If what you want to do is just map the main application and then fill the model you can use the idle_add gobject function to iterate over your data and then store it in your model without freezing your application, but it is at the same way, the slowest. You can put chunks of 20 or so, then every time you application runs the callback function will run a small but faster insertion. Anyway, this is still a bit slow.

I have been doing tests with 100,000 rows, in the easy way there are just numbers using a for cycle via a range() result.I think in Gtk, the smaller is the data stored in the model, the faster it goes, because I can insert 100,000 rows in a gtk.ListStore in 7 seconds aprox. while in christine, inserting 2600 row in christine (with more data per cell) takes a lot more.

Anyway, the application that I'm developing shows a list of customers, this is a growing list as new customers are added, in our tests we need to show up to 17,000 customers. Using gtk.ListStore takes at least 17 seconds on my machine just to show it, but we also have a filter model becuse search in a list of 17000 items is not easy if you go looking every row by hand. So, usig the FilterModel takes almost the same time in searching something. Obviusly, waiting 17 seconds for the result is not an option, even worse, you made a mistake and wrote LOPEX instead LOPEZ.

So, I was searching over internet what can I do. I have already use the common 'tweaks' to improve the gtk.ListStore performance and I have reached the 8 - 9 seconds over those 17,000 items, but even with this, its too much time. The search points me to the gtk.GenericTreeModel. This generic model allows you to create a custom model where you can make your own tweaks to improve the performance of your model. In the link above gives you the way to use it. I have alreade created my own custom model and it really relly made the things better.

Now, one of the problems that gtk.GenericTreeModel have are the memory leaks. Using this model you may use lots of memory. This is because the GTM use to create a reference to the value that you are returning as Iter, e.g. you are using a list of lists, where you store the values, every item in the list is a row, then, the index if the iter wich references to the list you are storing in that row. The problem is that the GTM increase the reference count of you node (the list inside of the list) to aviod row destruction and then use the iter. This, in the best will make your values been refered until you destroy your model (and any reference to the data), in the worse the reference count of your data will never been unrefered and then the memory will never be freed.

You can use the invalidate_iters every time you modify the rows (add or delete) to make the rows invalid and then decrease the reference count of the row, and when your data have no more references then be deleted. But, I have the problem that the reference count was never decreased when I destroy the window or the model. Where is the trick here, use the Python's garbage collector, and your memory will be freed.

So, the new model based on PyGtk's GenericTreeModel actually works for us. Inserting 17,000 takes just 1 second, and the search (filter) is the same thing, 1 second is an option. I would like to see everything just appear when you request it, but one second is good for now. And testing with my current christine music list it takes just 0.06 seconds to show the list. Inserting 100,000 items (the easy way, just numbers) takes just 1.164 seconds to get filled with four columns and 2.36 seconds to show itself (creating a filter model and setting it to a treeview), so, for now this kind of optimizations will work for us, there are other optimizations on the Filter model and the treeview, My goal is to create something similar to wat Aaron bockover do with banshee.

Note: Test times are approximate, cache, cpu usage, load average and other may cause the times change, but at the end give us an idea of what is going on.

Testing the new christineConf module

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sat, 03 May 2008 23:58:14 -0500

Testing the new christineConf module, originally uploaded by markuz.

I have been working in the configuration module for christine, something similar to gconf, but just for christine. Why? well, many people complains because christine needs the gnome-extras package, where gconf is, and to be honest, christine didn't use all the gconf power, so, there isn't a big reaons to keep gconf on christine.

This isn't the only thing I have been working on. I'm trying to improve many things for the next release. Most of the work wil be in the list, zodman gives me some nice ideas, and I will try to implement them.

Anyway, you are also invited to work with me in the christine development. You can join the maling list for the next release.

Christine 0.1.6

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 29 Apr 2008 15:10:06 -0500

CLick to enlarge This is the new release of Christine Media Player. This release include:

Some bugfixes
Reworked code in Sources list
Reworked display.
Improved import code (no more freeze while looking for the media files)
Multiple Sources list.
Translate Christine and Report a bug menuitems

You can download it from sourceforge:

Nearshoring... The Movie!

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 18 Apr 2008 13:05:47 -0500

PyGTK y Threads

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 10 Apr 2008 18:51:44 -0500

Es facil, al inicio de tu aplicacion tendras que inicializar los threads, que son algo asi:

gtk.gdk.threads_init()

Esto lo tendras que hacer antes de iniciar algun thread. Y luego, al usar algun thread debes englobarlo dentro de

gtk.threads_enter()
thread.start_new(funcion, (arg1,arg2,argN))
gtk.threads_leave()

Solo recuerda que no debes manipular gtk fuera del thread en el que esta corriendo el ciclo principal (gtk.main_loop).

Si lo que necesitas es estar cachando informacion en un thread aparte y modificar la interfaz (ej. Leyendo un socket y mostrando informacion de cuanto llevas leido) entonces usa alguna bandera y modifica tu apariencia en el thread principal, de lo contrario tendras problemas con gobject y glib.

Algo de amor para cristine

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 25 Mar 2008 16:50:02 -0500

Bien, hoy ha sido un pequenio dia para dar amor a christine, Hoy he tenido un poco de tiempo libre para 'descansar', Ayer cristina y yo nos fuimos a conocer Guanajuato, pronto pondre las fotos y la reseÃ±a.

Hoy, despues de hacer los quehaceres de la casa me sente un rato a cubrir una necesidad en especial que he tenido en Christine. Bien, pues resulta que a cristina le gusta mucho la musica en espaÃ±ol, en particular la movida, mientras que a mi me gusta mas la musica en inglÃ©s, El problema es que la gran mayoria de la musica en espaÃ±ol la he copiado de varios lugares y no la tengo en mi directorio de musica tipico, y tampoco lo tengo dentro de mi lista de canciones normal. Que pasa cuando cristina quiere escuchar su musica, tengo que entrar en ~/.christine y copiar el archivo music a algun otro, despues copiar el archivo de musica de cristina a music, y lo mismo cuando quiero poner mi lista de canciones. Un poco engorroso, aunque no lo hago muy seguido. Hoy he hecho un pequeÃ±o cambio a christine de forma que es posible selecionar la lista de canciones. Por hoy, en este lado es suficiente, aun le falta pulir, pero lo hace con mas tiempo y despues.

Tambien estuve trabajando un poco para corregir unos pequenios problemas con los menus, que no se muestran traducidos, esto debido a que en los archivos de descripcion de glade las etiquetas no tienen la propiedad translatable (en los menues). Tambien he agregado al SVN los archivos de traduccion creados en Launchpad. En fin, estos cambios ya estan disponibles en el SVN de christine.

Translation status

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 12 Feb 2008 16:57:22 -0600

It's nice to see that since yesterday to today there are already three new languages in the christine translations.

Wanna help? Translate christine HERE!

christine 0.1.5

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 05 Feb 2008 15:34:41 -0600

I have finally found a small time in my life to give a little love to christine and I'm not so proud (because of the delay) of the fifth revision of the fifth revision of the 0.1 version.

This fixes some bugs that I have found since the 0.1.4 but to be honest, I don't remember them. You can download the source packages from Here. There is also an Ubuntu Gutsy Package there.

Speed up gtk.ListStore

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 06 Dec 2007 15:24:50 -0600

Alguien sabe de algun algoritmo o forma para acelerar la insersion de elementos en un ListStore?. He estado haciendo pruebas con Christine sobre una lista de ~14000 canciones y mi pobre maquinita tarda entre 20 y 24 segundos para llenar el ListStore.

Se, que podria mostrar Christine y dejar que una llamada con idle_add haga la chamba, es decir, christine se mostraria en menos de 1 segundo, pero el idle_add me retrasa mas la carga de la lista a unos 2 minutos.

Alguien con algun comentario, enlace o similar, seria mas que apreciado.

Profiling Python

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 22 Nov 2007 08:40:15 -0600

Interesante articulo si te interesa ver que onda con los cuellos de botella de tu aplicacion en python: Profiling and Optimizing Python

Widgets 'recortados' en Gtk

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 09 Nov 2007 17:59:37 -0600

La mayoria de los widgets en Gtk tienen una ventana asociada, y no precisamente la ventana con decoracion que todo mundo ve. Gtk adiere una propiedad llama "window" a los widgets al ser empacados, o emparentados a otro widget contenedor.

Generalmente estos widgets son de apariencia rectangular, pero es posible tunearlos para que tengan la forma que nosotros queremos. La forma mas facil de hacerlo es tomar una imagen un usarla como "Molde" para crar nuestro contenedor recortado. aunque tambien es posible dibujar lo que nosotros querramos usando las funciones de cairo sobre un contexto (Que en si, es lo que hacemos con la imagen molde, pero mucho mas sencillo).

Lo que hacemos es obtener un molde a partir de una imagen, es decir, abrimos la imagen y creamos un gtk.gdk.Pixbuf, que es el mostraremos, pero podemos obtener el gtk.gdk.Pixmap y la mascara de este Pixbuf de forma que podamos usar dicha mascara para crear el contorno de nuestro widget.

Los widgets, una vez empacados,como ya habia dicho obtienen una propiedad llamada window, que pertenece a la clase gtk.gdk.Window. Aquellos que ya se han puesto a dibuar algo con cairo se habran dado cuenta que se obtiene un contexto de un widget a partir de su gtk.gdk.Window.

Bien. tambien es posible obtener este contexto de cairo a partir de un pixmap, hacer el dibujo molde y luego pegarselo a la ventana para que gtk.gdk sepa que partes ha de dibujar y cuales no.

Veamos un pequenio ejemplo.

class shapedWindow(gtk.DrawingArea):
def __init__(self):
gtk.DrawingArea.__init__(self)

self.__pixbuf = gtk.gdk.pixbuf_new_from_file('./logo.png')

self.connect('size-allocate',self.size_allocated)
self.connect('expose-event',self.do_expose_event)

self.set_size_request(self.__pixbuf.get_width(),
self.__pixbuf.get_height())

def size_allocated(self,win,allocation):
w,h = (allocation.width, allocation.height)
self.bitmap = gtk.gdk.Pixmap(None,w,h,1)
context = self.bitmap.cairo_create()

self.do_expose_event(self,'',context)

parent = self.get_parent()
win.shape_combine_mask(self.bitmap,0,0)
parent.shape_combine_mask(self.bitmap,0,0)

def do_expose_event(self, widget, event,allocate = False):
if allocate:
context = allocate
else:
context = self.window.cairo_create()

if allocate:
context.set_operator(cairo.OPERATOR_DEST_OUT)
w,h = (self.allocation.width, self.allocation.height)
context.rectangle(0,0,w,h)
context.set_source_rgb(1,1,1)
context.paint()

context.move_to(0,0)

context.set_operator(cairo.OPERATOR_OVER)

if allocate:
pixmap,mask = self.__pixbuf.render_pixmap_and_mask()
context.set_source_pixmap(mask,0,0)
else:
context.set_source_pixbuf(self.__pixbuf,0,0)
context.paint()

if __name__ == '__main__':
window = gtk.Window()
window.set_decorated(False)
a = shapedWindow()
window.add(a)
window.show_all()
gtk.main()

Que es lo que hacemos aqui? bien, primero creamos un widget personalizado usando gtk.DrawingArea y conectamos la sennial size-allocate para poder establecer el tamanio de nuestro widget. Una vez llamada esta funcion creamos un pixmap vacio del tamanio de nuestro widget, que es el tamanio que nos ha dado el contenedor padre, este es un rectangulo como de costubre, con un ancho y alto. A este pixmap le sacaramos el cairo context, sobre el cual hemos de 'dibujar' nuestro molde.

Como en este ejemplo el widget y su molde de la misma forma estoy aprovechado el metodo do_expose_event para hacer el dibujo inicial y despues hacer las funciones de redibujado en caso de un evento de expose.

Quienes hacen la chamba aqui? bien, para el dibujo inicial de nuestro widget es context.set_source_from_pixmap(), aunque podriamos usar el mismo set_source_from_pixbuf he detectado problemas con colores en Windows, entonces no lo recomiendo.

Otro que entra en juego y es el que le dice al widget 'orale cabron, apegate a esta forma' es win.shape_combine_mask(self.bitmap,0,0).

De ahi, el ponerle contenido a nuestro widget no es mas que un amanipulacion de colores y demas dentro de nuestro contexto cairo. Que, es otro tema del que hablar, como 'dibujar' lo que queremos en nuestro widget usando su contexto cairo.

Tamanio Completo

Ciertamente, el logtipo de Christine es el widget 'recortado'

Sockets

markuz@islascruz.org (Marco Antonio Islas Cruz) — Wed, 31 Oct 2007 18:22:09 -0500

Que bonito es usar sockets con python. Esta semana he estado trabajando con sockets para crear una interfaz de servidor y clientes que se comunican unos con otros a traves del servidor. En la imagen de abajo tenemos dos clientes, uno tiene su interfaz en GTK+ que es el que corresponde a la termina de la esquina inferior izquierda. Otro cliente es puro texto, que es el que esta en la parte superior, y el servidor es la terminal alargada que esta en el centro.

Lo que muestran las terminales no es mas que pura informacion loggeada usando el modulo logging de python

En los proximos dias, ya que tenga el codigo mas limpio vere la forma de ponerlo al publico.

Imprimir a un archivo PDF usando GTK.

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 19 Oct 2007 10:22:02 -0500

Perfecto. En esta semana me ha tocado estar trabajando sobre un programita que ando haciendo, el cual debe correr sobre Linux y MS Windows >= 2000. El desarrollo se esta haciendo en Python usando GTK para la interfaz grafica, pero me he encontrado uno que otro problemita con GTK, sobre todo con el manejo de ventanas, aunque el que mas tiempo me ha llevado ha sido el de impresion.

Gtk+ a partir de la version 2.10 incluye soporte para impreision en Linux y otros Unix'es gracias a CUPS, mientras que en Windows lo hace de manera nativa con el sistema de impresion de Windows.

Debo decir que en linux esta cosa es la maravilla, En windows no tanto, pero funciona decentemente si tus requerimientos no son tan especiales.

Los requerimientos para imprimir son estos:

Debe imprimir en la impresora por defecto

NO debe mostrar el dialogo de seleccion de impresora

Debe imprimir en el tamanio determinado por el programa

En linux, repito, esto es una maravilla, solo le digo imprime usando la constante gtk.PRINT_OPERATION_PRINT y con esto no me muestra el cuadro de dialogo, previamente he creado la operacion de impresion y le he dicho que seleccione la impresora por defecto, en linux, si en settings.set_printer() le pasas el parametro '' usa la impresora por defecto, es mas, si no usas el metodo set_printer usa la impresora por defecto.

Pero en Windows la cosa no es tan bonita. para empezar Siempre muestra el cuadro de seleccion de impresora (punto menos). Y para acabarla de amolar, aunque tengas una impresora predeterminada y esta impresora este seleccionada mandas imprimir (Alt +m o ENTER) habra un error porque GTK no ha configurado las cabeceras de impresion para mandarle el 'win32-driver', 'win32-driver-extra' y otros parametros fumados de los que Windows sabe. Obviamente, si seleccionas otra impresora y regresas a la que esta por defecto estos parametros son llenados y entonces la impresion funciona "bien". Obviamente, como no queremos que el usuario vea el cuadro de impresion esto no es opcion.

Lo siguiente es, obtener la impresora por defecto y mandar establecer los encabezados, para esto se pueden valer del modulo win32print

import win32print

printerName = win32print.GetDefaultPrinter()
printer = win32print.OpenPrinter(printerName)
printerValues = win32print.GetPrinter(printer,2)
dir(printerValues['pDevMode'])

Y pueden valerse del gtk.PrintSettings.set() para poner los encabezados.

Esto les sera util cuando ustedes quieran mostrar el cuadro de impresion, a fin de que lo muestre y espere una configuracion por parte del usuari, o en caso de que no se configure nada por parte del usuario, usar las configuraciones por defecto.

Hasta aqui todo bien, pero, Yo no quiero el cuadro de impresion!, solo quiero que imprima.

Bien, yo no queria hacerlo asi, pero pues bueno, no hay de otra.

if os.name == 'nt':
filename = './ultimafactura.pdf'
op.set_export_filename(filename)
action = gtk.PRINT_OPERATION_ACTION_EXPORT
elif '-d' in sys.argv:
action = gtk.PRINT_OPERATION_ACTION_PRINT_DIALOG
else:
action = gtk.PRINT_OPERATION_ACTION_PRINT
try:
response = op.run(action)
except:
response = gtk.PRINT_OPERATION_RESULT_ERROR
if response == gtk.PRINT_OPERATION_RESULT_ERROR:
settings = op.get_print_settings()
settings.foreach(funcPrintKeys)
print "Hubo un error a imprimir"
elif response == gtk.PRINT_OPERATION_RESULT_APPLY:
if os.name == 'nt':
filename = './ultimafactura.pdf'
import win32api
win32api.ShellExecute(0,
'print',
filename,
None,
'.',
0)

La solucion ha sido crear un archivo PDF, usando el PrintOperation.set_export_filename() para despues usar win32api.ShellExecute() para imprimir.

Que es lo que hace ShellExecute?. Bien, ejecutara el comando que tu le des, en este caso 'print' sobre el archivo dado por el siguiente parametro "filaname", el siguiente parametro son los parametros al programa que va a realizar la operacion, el siguiente, el directorio de trabajo y por ultimo un valor entre 0 y 1 que dice si se ha de mostrar o no la ventana del programa que ha de realizar la operacion.

Para esto, es necesario tener en Windows un programa que pueda abrir e imprimir PDF. Obviamente el mas conocido es Adobe Acrobat Reader, pero Adobe Acrobat Reader es un Monstruo si lo unico que queremos es impresion. Asi que, lo que he hecho es utilizar Foxit PDF Reader, el cual es mucho mas ligero y rapido.

Y eso es todo, ese ha sido el cucharazo porque GTK por defecto no te utiliza la impresora por defecto, ni te esconde el cuadro de impresion en Windows.

En fin. el chiste es lograr que las cosas jalen.

Un ejemplo sencillo de impresion lo pueden encontrar Aqui

CakePHP + Scriptaculous

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 09 Oct 2007 12:40:14 -0500

He empezado a trabajar sobre cakephp y scriptaculous, por lo poco que he visto esta muy sencillo en el aspecto de casi no escribir nada. Ya veremos con que me salen despues

Christine 0.1.1

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 21 Sep 2007 14:10:38 -0500

El equipo de desarrollo de Christine se complace en presentarles la nueva version de Christine, 0.1.1, Esta version es una version corregida de Christine 0.1, es decir, no implementa cosas nuevas, solo mejora lo que ya estaba.

Pueden descargar las fuentes de Christine 0.1.1 Aqui, y revisar las notas de liberacion Aqui.

Gracias a todos los que han cooperado con el desarrollo de Christine.

Usando el widget creado anteriormente

markuz@islascruz.org (Marco Antonio Islas Cruz) — Fri, 14 Sep 2007 16:45:01 -0500

Despues de crear el widget en puesto en el post anterior, hoy me lo he implementado en el sistema que estamos creando en ICT Consulting. El video esta chidin, pero Google lo hace ver horrible. En fin, es solo demostrativo.

widgetTest.ogg

Un contenedor GTK Redimensionable al gusto.

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 13 Sep 2007 16:28:18 -0500

Uno de los widgets menos usados en GTK es el gtk.Fixed, Este contenedor nos permite poner widgets de manera estatica en nuestra aplicacion. Es decir, si la ventana cambia de tamanio los widgets no se redimencionaran y tampoco cambiaran de posicion. Pocos lo utilizan por esto, pero a veces es necesario.

Pues resulta que en una de las aplicaciones lo tengo asi, simplemente porque los widgets NO se tienen que mover ni cambiar de tamanio si la ventana se redimenciona, aqui yo lo veo como algo bueno. En fin, El problema del GtkFixed es que nomas no me cacha los eventos, y meterlo en un gtk.EventBox me parece no tan optimo, puesto que yo quiero que los eventos los cache el Widget, no un EventBox.

Mi primer intento de solucion: Crear una clase que herede de gtk.Fixed y cachar los eventos para que cuando el cursor este dentro de un punto determinado se pueda redimencionar al muy puro estilo de click-arrastra-suelta. Problema, gtk.Fixed no me cacha los eventos, incluso si se los agrego a manita con gtk.Fixed.add_events.

Segundo intento: Hereda primero de un gtk.EventBox y luego de un Fixed: Si cacha los eventos, No te muestra ni madres. Inviertelo, Si te dibuja, pero no te cacha los eventos... (ya me estoy desesperando)

La solucion?, Bueno, nunca le habia echado el ojo al gtk.Layout, entonces heredo de un gtk.Layout primero, este no me cacha los eventos, pero, me permite dibujar como si fuera un gtk.DrawingArea aunque tienes que dibujar sobre el bin_window de tu layout (gtk.Layout.bin_window) en lugar del window como tipicamente se hace en gtk.DrawingArea. Bien, tu segunda herencia es de un EventBox para poder cachar las seniales, y listo .

Es importante que Primero se herede de gtk.Layout y luego de algun otro widget (gtk.DrawingArea tambien funciona) para que Gtk no reniegue al tratar de agregar widgets a tu gtk.Layout.

El codigo seria mas o menos asi (Estoy seguro que de alguna manera se puede mejorar):

class groupWidget(gtk.Layout,gtk.EventBox):
'''
Una version modificada del gtk.Fixed
'''
def __init__(self):
gtk.Layout.__init__(self)
gtk.EventBox.__init__(self)

self.__buttonPressed = False

self.connect('expose-event',self.__exposeEvent)
self.connect('motion-notify-event',
self.__motionNotify)

self.connect('button-press-event',
self.__buttonPressEvent)
self.connect('button-release-event',
self.__buttonReleaseEvent)

def __motionNotify(self,widget,event):
if self.__buttonPressed:
x,y = self.get_pointer()
if (x,y ) > (0,0):
self.set_size_request(x,y)
self.__lastWH= [x,y]

def __buttonPressEvent(self,widget,event):
w,h = self.__lastWH
px,py = self.get_pointer()
if event.button == 1:
if w > px > w-5 and h > py > h-6:
self.__buttonPressed = True

def __buttonReleaseEvent(self,widget,event):
if event.button == 1:
self.__buttonPressed = False

def __exposeEvent(self,widget,event):
'''
Encargada de dibujar el widget
'''
context = self.bin_window.cairo_create()
x,y,w,h = self.allocation
self.__lastWH = [w,h]
context.set_line_width(1)
context.set_antialias(cairo.ANTIALIAS_NONE)

#Dibujamos el relleno y el borde
context.move_to(0,0)
context.rectangle(1,0,w-1,h-1)
context.rectangle(1,0,w-1,h-1)
context.set_source_rgba(1,1,1,0.5)
context.fill_preserve()
context.set_source_rgb(0,0,0)
context.stroke()

#Dibujamos un pequenio rectangulito
# en la parte inferior derecha.
context.rectangle(w-5,h-6,5,5)
context.set_source_rgb(0.5,0.5,0.5)
context.stroke()

Y se deberia ver asi:

En el video se puede apreciar que el boton esta dentro del contenedor, por eso de corta cuando el tamanio del contenedor es menor (se pueden usar Scrollbars gracias a la capacidad de gtk.Layout.

Respuesta

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 09 Aug 2007 15:38:02 -0500

Esto Iba a ser un comentario mas, pero creo que seria bueno que estuviera a vista de todos.

Armando: En las escuela esta muy dificil que te ensenien a usar PHP, y esta aun mas dificil que te ensenien a usar Python, mas cabron aun, que te ensenien a usar GTK. Desafortunadamente en mexico las escuelas estan dedicadas a enseniar cosas como Java o .NET porque:

1.- Es un circulo vicioso, los profesores lo saben, lo ensenian a los alumnos, los alumnos aprenden, la mayoria de los alumnos no aprenden otra cosa, y cuando les toca enseniar solo pueden enseniar lo que saben, asi terminan dando Java.

2.- Muchas escuelas estan casadas con Microsoft, asi que por fuerza lo han de dar .

De PHP hay infinidad de libros, y tutoriales libres muy buenos por la red, el libro con el que yo empece con PHP es con el de 'Proyectos Profesionales con PHP' de editorial ANAYA,

De Python, te recomiendo el tutorial de python que esta en la documentacion de python, 'Dive Into Python' y 'How to think like a computer scientist learning with python' .

De Gtk, Hay un tutorial muy bueno en la documentacion de PyGTK.

Un comentario, si piensas aprender PHP para usar GTK, te recomiendo mejor aprender Python para usarlo con GTK.

Amo a PyGTK

markuz@islascruz.org (Marco Antonio Islas Cruz) — Wed, 08 Aug 2007 08:34:08 -0500

En esta semana, he estado trabajando en un programita que se mete con la base de datos del CRM que usan en ICTC, resulta que en el CRM se tienen tareas, clientes y demas cosas, pero hay que tener el navegador web abierto para poder echarle un ojo a las tareas pendientes, o para obtener informacion de algun cliente. Bueno, mi chamba ha sido que con Python y GTK haga una pequenia aplicacioncita que se meta en el area de notificiacion y desde la cual facilmente se puedan consultar las tareas, los clientes y otras cosas.

Aun no termino el programa, me faltan varios detalles, pero para 2,3 dias que llevo en el vamos bien. Lo que me encanta es que programo desde linux con Vim y pruebo en windows. Obviamente, no se permite que cada maquina tenga una conexion directa con base de datos, asi que mejor abrimos un socket en una maquina 'servidor' y los clientes solo piden datos ahi.

En GNU/Linux

En Windows

Christine 0.1

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sun, 29 Jul 2007 13:29:01 -0500

Bien, hoy es mi cumpleaÃ±os, gracias a todos los que no me han felicidado hasta ahora, y gracias a todos los que ya me felicitaron.

He liberado la primera version de Christine, tal vez no es tan estable como yo quisiera, pero tengo planes par a christine que no van con el codigo que tengo ahorita, asi que lo mejor serÃ¡ liberar esto y empezar a codear en lo siguiente. Si encuentran bugs ya saben Donde reportarlos.

Que cambio con respecto de la 0.1rc2?. Bien corregi varias cosas, y mejorÃ© un poco algunas otras. Las correcciones no las recuerdo ahorita porque por lo general se almacenan en mi memoria temporal. Y las mejoras, pues mejore un poco lo del soporte para estaciones de radio y playlist m3u y el display que ahora usa los colores del theme.

Puedes descargar christine 0.1 Aqui.

Christine for birthday!

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 26 Jul 2007 12:56:34 -0500

Bien, no es mi cumpleaÃ±os,pero lo va a ser en unos dias, Esta semana he estado trabajando en christine un poquito, el domingo y lunes en algunas partes experimtentales de christine, implementando csoas como Piratearle Metodos a un objeto para hacer empapelados y crear un ambiente de desarrollo mas sencillo. Todo esto es en lo que se esta trabajando y formarÃ¡ parte de christine.

Otras cosas en las que he trabajado es en bugfixes para la version 0.1 y pequeÃ±as mejoras (que he de agregar lo otro). Lo mejor es que ahora christine tiene un mejor soporte para archivos m3u y pls y que tiene un "display" que ahora se dibuja con los colores del theme.

"Piratearle" las propiedades a un objeto en Python

markuz@islascruz.org (Marco Antonio Islas Cruz) — Tue, 24 Jul 2007 11:58:34 -0500

Supon que tienes una clase Uno y quieres que obtenga las propiedades de la clase Dos o Tres, Por que harias esto?, simplemente porque en tu programa no quieres lidiar con

import uno,dos,tres
if "uno":
refrerencia = uno()
elif "dos":
referencia = dos()
else:
referencia = tres()

Y despues averiguar sobre quien haces la instancia en cada parte de tu codigo que requiera una instancia, de hecho, no es escalable, agregar una referencia mas seria doloroso si tu codigo es grande. mejor es hacer un empapelado de las referencias y hacer instancia a una sola, y que esta se haga pelotas de a quien referenciar.

Una forma de acercarse seria usar esto:

class wrapper:
def __init__(self,modulo):
moduloobj = __import__("paquete",globals(),locals(),[modulo])
referencia = vars(moduloobj)[modulo]
self.__empapelado = referencia()

Para obtener refrencias de las propiedades de un objeto usamos getattr, getattr recibe como primer parametro el objeto en el que se buscarÃ¡ la propiedad y como segundo, el nombre de la propiedad en cadena.

def Query(self,metodo,*args):
'''
@param string metodo: Nombre del metodo en cadena
@param *args: argumentos a pasar al metodo.
'''
met = getattr(self.__empapelado,metodo)
if callable(met):
return met(*args) #ejecutamos el metodo y regresamos lo que nos regrese

Y tener:

a = wrapper("uno") #o "dos", o "tres"
a.Query("imprimeEsto","Texto a imprimir")

Esto, desde mi punto de vista es ideal, pues tu codigo es limpio, pero tal vez quieres hacer el empapelado sobre un proyecto que ya tiene rato jalando, y que todo se hace referencia a una clase, pero, quieres que esta clase ahora sea el "empapelado". Puedes Piratearle las propiedades a otro objeto, asi:

#!/usr/bin/env python

import paquete

class Pirata:
'''
Se piratea las propiedades de un objeto.
'''
def __init__(self,modulo,objeto):
'''
Constructor
'''
moduloobj = __import__(paquete,globals(),locals(),[modulo])
referencia = vars(moduloobj)[modulo]
pirateable = getattr(referencia,objeto)()
for i in dir(pirateable):
newkey = i.replace("_%s_"%objeto,"_Pirata_")
self.__dict__[newkey] = getattr(pirateable,i)

Para tener algo asi:

a = test.Pirata("modulo","clase")
a.imprimeEsto("Texto a Imprimir")

De esta forma, no cambias nada en tu codigo que ya tienes, simplemente, en alguna parte de tu codigo, indicas que el "empapelado" ha de piratearle las propiedades a otro objeto que haga las operaciones necesarias.

Como dibujar un imagen (jpg, png, gif, etc..) en Cairo

markuz@islascruz.org (Marco Antonio Islas Cruz) — Sat, 21 Jul 2007 10:57:58 -0500

Para dibujar usando cairo por lo general creas un objeto heredando propiedades de gtk.DrawingArea. y obviamente, tenemos un metodo para el redibujado. Dentro de ese metodo metemos esto:

def setPixbuf(self,pixbuf):
if type(pixbuf) != gtk.gdk.Pixbuf:
raise TypeError("Pixbuf debe ser %s recibido %s"%(gtk.gdk.Pixbuf, type(pixbuf)))
self.__Pixbuf = pixbuf
self.emit("expose-event",gtk.gdk.Event(gtk.gdk.EXPOSE))

def exposeEvent(self, widget,event):
x,y,w,h = self.allocation
try:
context = self.window.cairo_create()
except AttributeError:
return True

if self.__Pixbuf != None:
scaledPixbuf = self.__Pixbuf.scale_simple(ancho,
alto,
gtk.gdk.INTERP_BILINEAR)
ct = gtk.gdk.CairoContext(context)
ct.set_source_pixbuf(scaledPixbuf,BORDER_WIDTH,BORDER_WIDTH)
context.paint()
context.stroke()

Y listo

Creando tus propios objetos con gobject y error con las seÃ±ales.

markuz@islascruz.org (Marco Antonio Islas Cruz) — Thu, 05 Jul 2007 12:38:50 -0500

En GTK+ es mu tipico crear widgets personalizados, o en un caso muy simple, agregar seÃ±ales a tus funciones, no importa si dibujas algo o no. Bien, hay una forma de crear un objeto en Python y que te aparezca asi:

Pues es facil, en nuestra clase tendremos esto:

#notese que estoy haciendo una subclase de gtk.Widget.
class nombredeObjeto(gtk.Widget):
def __init__(self):
gobject.GObject.__init__(self)
self.set_name("nombredeObjeto")

gobject.type_register(nombredeObjeto)

Asi de facil , el nombre que mostrara despues del "<" sera lo que definas en set_name