Re: GUIs - A Modest Proposal
On 6 June, 23:55, ant wrote: >If we are to make progress, I can see two obvious approaches: >1) Improve Tkinter to the point where it is supportable and supported >by a good fraction of Python programmers >or >2) Drop Tkinter as the default and use something else. IIRC Guido has ruled out officialy adopting a full-bore GUI toolkit such as WxPython or PyQT, or even a supercharged verison of Tkinter, into the standard library. There are two main reasons. One is that doing so would more than double the standard Python distribution's disk footprint, to no advantage for non-graphical target systems or developers wanting to use native GUI APIs. Another is that it wouldn't make any of the other options go away, so e.g. if PyQT were chosen, anyone wanting to use WxPython would have to install it as well, creating even more bloat. GUI toolkits are major projects with their own development cycles and roadmaps that may not match with that of the standard library. They are also still rapidly evolving. The standard library should only contain stable, mature code bases. Furthermore the core Python dev team have limited resources. Increasing the officialy maintained code base by 2x or more just isn't supportable. Tkinter is perfectly adequate for basic GUIs. If you want something more sophisticated there are plently of high quality, well documented alternatives to match your platform or functionality requirements. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Generic spreadsheet interface
Hi Bro, I don't know of anything like that. The spreadsheet sites I do know of are application-specific. http://www.python-excel.org/ http://wiki.services.openoffice.org/wiki/Python http://lucasmanual.com/mywiki/OpenOffice Note that the OO.o bindings for Python are only for Python 2.3 which is a little archaic, but it's the version I started with and should be more than good enough for spreadsheet work. A port to 2.5 is well underway. You'd probably need to write your own application-specific wrapper modules with a common API and then use those, but it's probably not as much work as it sounds and could be developed incrementaly. Alternatively you just write your code against one spreadsheet module, and then write a wrapper module for the other spreadsheet API so it looks the same. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem with win32ui
On 23 Dec, 11:10, Marc Grondin wrote: > On 22/12/2009 1:05 PM, Gabriel Genellina wrote: > > > En Tue, 22 Dec 2009 12:31:37 -0300, Marc Grondin > > escribi : > > >> Hello everyone, > >> So i have been building an app with python(and learning as i go along) my > >> knowledge of python is still kinda limited but the app work on my pc. > >> I have > >> also compiled it to an exe using py2exe and it also works fine this > >> way on > >> my pc(where python is installed) if however i try to run it from a pc > >> where > >> python is not installed i get this message: > > >> Traceback (most recent call last): > >> File "printorders.py", line 2, in > >> File "win32ui.pyc", line 12, in > >> File "win32ui.pyc", line 10, in __load > >> ImportError: DLL load failed: The specified module could not be found. > > > There is a missing DLL. Dependency Walker is a useful tool to solve this > > kind of problems: > >http://technet.microsoft.com/en-us/library/cc738370(WS.10).aspx > > Once you know which DLL is missing, add it to your setup.py > > ok so that got me a little further. The app now works on win2k and > windows 7 but on winXP i get this: > > File "printorders.py", line 2, in > File "win32ui.pyc", line 12, in > File "win32ui.pyc", line 10, in __load > ImportError: DLL load failed: This application has failed to start > because the a > pplication configuration is incorrect. Reinstalling the application may > fix this > problem. > > Dependencie walker does not find any major issues. what am i missing here. > > thank you in advance for your help. You could try and find out what the __load statement in line 10 in win32ui.py does. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: python gui builders
On 18 Nov, 22:11, Stef Mientki wrote: > Simon Hibbs wrote: > > On 18 Nov, 07:51, sturlamolden wrote: > > >> GPL > > > PyQT is GPL for now, but Qt itself is available under the LGPL as is > > PySide. Eventualy PySide, which tracks the PyQT API, will supplant it > > and the issue will be moot. For now it can be a problem, but PyQT > > developer licenses are very afordable at only a few hundred dollars. > > If a commercial project can't aford that, it's got problems. > > > Only you can know enough to make an informed decision. Wx does look > > more usable than last time I used it for a project and is a fine > > option too, for me though QT is the gold standard against all others > > are measured, and generaly found wanting. > > > Simon Hibbs > > Wouldn't it be nice > if each fan of some form of GUI-package, > would post it's code (and resulting images) for generating one or two > standard GUI-forms ? > > Then everyone can judge the differences, > and see what's simple and not so simple !! I don't think a list like this is a great way to do that. There are plenty of examples and tutorials available for each option. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: is there any FIX message handle modules in Python?
On 19 Nov, 05:25, alex23 wrote: > On Nov 19, 3:21 pm, "Stephen.Wu" <54wut...@gmail.com> wrote: > > > FIX message is the "Financial information Exchange" protocol > > messages... > > any 3rd libs we have? > > You mean like this one that was the first result when I googled > 'python "financial information exchange"'? > > http://www.quickfixengine.org/ There are no prebuilt Python modules available based on quickfix, at least that I'm aware of. It has Python bindings available, but you have to complie it with them yourself from the C++ source. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: python gui builders
On 17 Nov, 23:25, Kevin Walzer wrote: > On 11/17/09 4:25 PM, Tim Daneliuk wrote: > > > +1 Tkinter for the simple stuff > > You can actually use Tkinter to do quite sophisticated GUI's that rival > anything found in Qt or wx... Neither Tkinteror Wx have anything that come close to QGraphicsView, the Model-View-Delegate framework, the Phonon multimedia framework integration, QtSQL, QtXML, QtSVG, and the many other first grade components in Qt. You can substitute components from other frameworks, e.g. for database access, but then you lose the integration QtSQL has with the model-view-delegate features in other parts of the Qt world. Qt is much more than just a GUI framework, it's more of a rival to something like the MacOS development libraries, or the .NET framework in terms of the library facilities it offers. I think that's why Nokia bought into it. Qt provides them with a platform with the potential to rival the iPhone dev environment. Of course to take full advantage of it you need to invest in learning it all, which is non-trivial. It comes at a cost in time and potential lock-in. But the point is you can't just say Qt is just like Wx. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: python gui builders
On 18 Nov, 07:51, sturlamolden wrote: > > GPL PyQT is GPL for now, but Qt itself is available under the LGPL as is PySide. Eventualy PySide, which tracks the PyQT API, will supplant it and the issue will be moot. For now it can be a problem, but PyQT developer licenses are very afordable at only a few hundred dollars. If a commercial project can't aford that, it's got problems. Only you can know enough to make an informed decision. Wx does look more usable than last time I used it for a project and is a fine option too, for me though QT is the gold standard against all others are measured, and generaly found wanting. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: python gui builders
On 16 Nov, 10:06, me wrote: > What Python gui builder is well supported, does not require me > to learn another framework/library, and can crank out stuff for > multiple platforms ? You're looking for a framework/library that doesn't require you to learn it. OK I've had this problem for a few years. I've tried PythonCard, WxWidgets with WxDesigner, BoaConstructor, etc. None of them come anywhere close to PyQT/QTDesigner. Dion't get Blackadder It hasn't been updated for several years and is a dead project. In any case it uses QTDesigner for GUI layout anyway. You're better off using Eric or Wing if you want a decent IDE. QT does have a learning curve of course, but you get a lot of power back in return for the investment. I'm just coming to grips with it's MVC framework and the book "Rapid GUI Programming with Python and Qt" is very helpful with that. I wouldn't completely dismiss Tkinter. It's too simple for complex GUIs but I still think it has it's place for basic utilities. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Choosing GUI Module for Python
On 10 Nov, 10:40, Lorenzo Gatti wrote: > I also would like to use PySide, but unlike PyQt and Qt itself it > doesn't seem likely to support Windows in the foreseeable future. A > pity, to put it mildly. It's not been ruled out. They don't officialy support the Mac either, but according to posts on the mailing list a independent developer has got it working in MacOS X at some level. Since QT runs on Windows, porting to the Windows version of QT shouldn't be hard. PySide is for the future, not the present, but it gives me a lot more confidence in using and recomending PyQT to know that there is so much work being put in to make sure it has a great future. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Choosing GUI Module for Python
Having tried most of the options out there, personaly I've settled on two. I use Tkinter for ver simple GUIs such as single dialog boxes or results displays. The advantage of it being built-in to Python outweighs it's limitations. For anything more complex, I go for PyQT every time. QTDesigner is a full drag-and-drop GUI builder that rivals Visual Studio, and PyQT comes with a script to convert QTDesigner XML files into Python code, which you then subclass in your own script and attach your own code to the GUI widgets. There's a longer learning curve than Tkinter, but it's very much worth it for access to QTs mature and rich framework, with excellent professional-class documentation. Sorry, but wxWidgets which I have used doesn't come anywhere close. The main objection to using PyQT untill now was that for commercial development you needed to buy a license (it was free for GPL projects). That's rapidly becoming a non-issue as the core QT framework is now LGPL and Nokia have a project underway to produce PyQT compatible LGPL python bindings under the PySide project. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Command parsing... best module to use?
On 3 Nov, 01:14, Collin D wrote: > Thanks for the replies. Pyparsing looks just like what I need. The cmd module in the standard library is fine for simple command interpreters. Depending on your needs you might find it does what you want. Doug Hellmann has covered it in his "Python module of the week" series of articles. http://www.doughellmann.com/PyMOTW/cmd/index.html Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: how to modify row content of file in python?
On 27 Oct, 07:55, holmes86 wrote:
> hi,everyone
>
> Is there function of modify row content in python? just like 'sed' in
> shell,thanks
You would do something like this, which acepts a CSV file from stdin
and sends the first column to stdout (prints it), which you could
redirect to a file or pipe to another command.
import sys
with infile = sys.stdin.readlines():
for line in infile.readlines():
columns = line.split(',')
print columns[0]
This code is not tested as Windows Explorer just crashed on my box
(effing windows - I'm at work so no Mac. *sob*).
One thing to look out for is that 'columns' is being created each time
through the loop, which works fine. If you modified the code to append
to it instead, you would need to create it before entering the loop as
you can't append to something that doesn't exist.
Simon Hibbs
--
http://mail.python.org/mailman/listinfo/python-list
Re: Converting a PIL image object to a buffer
On 2 Apr, 08:28, "Diez B. Roggisch" wrote: > Simon Hibbs schrieb: > > > > > On 1 Apr, 21:43, Gary Herron wrote: > >> Simon Hibbs wrote: > >>> I'm trying to dump a snapshot of my application window to the > >>> clipboard. I can use ImageGrab in PIL to get the screen data into a > >>> PIL image object, which i have converted to a bitmap using ImageWin, > >>> but when I try to pass this to the clipboard using - > >>> win32clipboard.SetClipboardData(win32clipboard.CF_BITMAP, img) > >>> It fails, telling be that "The object must support the buffer > >>> interface". > >>> How can I convert a PIL image into a buffer object? I can't find any > >>> clues. > >> PIL images have a tostring method that returns a string containing all > >> the pixel data. Would that help you to either create the needed > >> buffer? Or perhaps you could by-pass the need for a buffer, and just > >> use the byte string. > > > If I use tostring I get a string which I can put on the clipboard, but > > it isn't any kind of image. I can make a PIL image from the string but > > them I'm back to square one again. > > Did you actually try that? Strings support the buffer interface, and the > type of the binary data you set should be defined by the first argument. > > Alternatively (if the string is not of the proper format), maybe storing > the image to a (c)StringIO-object as BMP and retrieving it's value would > help. > > However, I think your concerns about "wasting memory" when using a file > are moot - creating an extra memory buffer isn't less memory consuming, > and if the file is living only a few seconds it might not even actually > hit the disk at all. In the end, the important thing is the working > clipboard. Yes I did try this, the code to dump the sting version to the clipboard worked, but pasting it back out wasn't possible although I could print them to the console. I don't mean wasting memory, just that actualy hitting the file system and creating a file seems as though it shouldn't be necessery. Is there any good reason why you can't just create an empty buffer object or file object directly? It seems like an unecessery restriction, unless there's some underlying reason such as that it's hard to implement in c, which seems implausible. Sorry, that's a rhetorical question. I've not had a chance to work on this today, if I find an elegant way round it I'll post the results for future googling. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Converting a PIL image object to a buffer
On 1 Apr, 21:43, Gary Herron wrote: > Simon Hibbs wrote: > > I'm trying to dump a snapshot of my application window to the > > clipboard. I can use ImageGrab in PIL to get the screen data into a > > PIL image object, which i have converted to a bitmap using ImageWin, > > but when I try to pass this to the clipboard using - > > > win32clipboard.SetClipboardData(win32clipboard.CF_BITMAP, img) > > > It fails, telling be that "The object must support the buffer > > interface". > > > How can I convert a PIL image into a buffer object? I can't find any > > clues. > > PIL images have a tostring method that returns a string containing all > the pixel data. Would that help you to either create the needed > buffer? Or perhaps you could by-pass the need for a buffer, and just > use the byte string. If I use tostring I get a string which I can put on the clipboard, but it isn't any kind of image. I can make a PIL image from the string but them I'm back to square one again. I suppse I could save the image object to a real file and then send that to the clipboard, but that seems wasteful and I'd have to worry about what to call it and where to put it. Much neater if I could just create it in memory somehow. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Converting a PIL image object to a buffer
I'm trying to dump a snapshot of my application window to the clipboard. I can use ImageGrab in PIL to get the screen data into a PIL image object, which i have converted to a bitmap using ImageWin, but when I try to pass this to the clipboard using - win32clipboard.SetClipboardData(win32clipboard.CF_BITMAP, img) It fails, telling be that "The object must support the buffer interface". How can I convert a PIL image into a buffer object? I can't find any clues. Help appreciated, Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: A little bit else I would like to discuss
On 13 Feb, 02:53, azrael wrote: > All I hear when I talk to people who own or eork in SW companies is > "Python? Isn't that that small scripting language. This will never > bring a real application." I am tired of hearing this. Even Microsoft > implemented Python. Only because the GUI building I am thinking about > of moving to IronPython. But this great comunity holds me bac on > CPython. I don't agree at all that Python can't compete with Visual Studio for GUI development. There are Python modules for Eclipse if you need an enterprise class IDE. For GUI design the PyQT GUI toolkit includes QT Designer - a fully featured graphical GUI builder every bit as capable as the one in Visual Studio. In fact I much prefer working in QT Designer for GUI layout, the Signals/Slots model for hooking up to the application logic is just so much more elegant and robust. If Eclipse is a bit heavyweight for you, and you're after a Pyhton equivalent to VB, I can't recommend Eric enough. It's a Python IDE written in Python using the PyQT toolkit, and integrates directly with QTDesigner. IMHO it's far superior to anything Microsoft has to offer, with full native support for MacOS X, Linux and Windows. The only fly in the ointment in licensing. The QT toolkit will be fully GPL and LGPL from version 4.4, but PyQT itself has a dual GPL/ commercial licensing structure. Still, it's relatively cheap and well worth it if you're goingt to do commercial development. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Python OOP advice
Great contributions, thanks both of you. I'm self-tought when it comes to Python and OOP and I haven't yet grown an intuitive feel for how to do things sensibly. Simon -- http://mail.python.org/mailman/listinfo/python-list
Python OOP advice
I'm rewriting a design application for a science fiction game. in it you design your own starships. Each component has a mass and cost, but the mass can either be fixed or it can be expressed as a percentage of the tonnage of the overall ship. Orriginaly I thought I'd need to have a hull object which contains component objects, but the component objects need access to members of the hull object (e.g. the hull size) so that looks messy to implement. I have defined a base class Component with a class member variable 'hull_size' so that all components can see the hull size. I've then got two child classes called Fixed_Component and Percent _Component that implement their mass, mass_percent and cost properties appropriately for their type. I've also defined a Hull class which also inherits from Component and provides methods for access to the hull_size class variable. I'm not sure where to go from here. One possibility is to have a Ship object containing a list of components, but I'd need to have a way to ensure there's only ever one hull object so maybe that shouldn't go in the list? I think the fact that the hull_size is a class member also means I can't ever have an application that loads two designs at the same time, because they'd share the same hull_size class variable. Is that so, and is there a way round that? I suspect the inheritance model will work fine at first, but is too rigid in the long run. Is there a way to cleanly implement a parent-child relationship between objects that gives child objects limited access to members of the parent? Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: creating color gradients using PIL
On 21 Nov, 06:30, Ramdas <[EMAIL PROTECTED]> wrote:
> Any ideas how we can create a color gradient using Python Imaging
> Library. Has any got some sample code that can give me some idea. I
> need to create a horizontal and vertical color gradient for a college
> project
>
> Thanks
I use these functions for building PIL images from numpy arrays
# Convert a 2-d array with typecode 'b' to an image with mode 'P'
def numpy2pil(arr):
rows = arr.shape[0]
cols = arr.shape[1]
m = arr.tostring()
out = Image.new('L', (cols, rows), 999 )
#out.fromstring(m)
out.fromstring(m, 'raw', 'L', 0, -1)
return out
def pil2numpy(im, typecode='b'):
# tostring does something funny with '1' images (packs em
tight).
# For 'P' images, the image data is not pased through the
palette.
if im.mode != 'L' and im.mode != 'P':
print 'im.mode must be "L" or "P"'
raise 'terminate'
xsize = im.size[0]
ysize = im.size[1]
m = im.tostring()
t = fromstring(m, 'b')
tt = asarray(t, typecode)
# Note that ysize is first:
return reshape(tt, (ysize, xsize))
im = numpy2pil(myarray)
im.putpalette(palette_list)
im.save('myimage.png')
You'll need to import numpy and Image. You'll need to generate the
palette (juust a list) and image array (a numpy array) of course.
Simon Hibbs
--
http://mail.python.org/mailman/listinfo/python-list
Re: python safe scripting
> > 2007/11/21, Vladimir Rusinov <[EMAIL PROTECTED]>: > Yes, but apache, nginx and others does not uses logger. > I wanna write an application which would handle all my (Linux) logs: > rotating, compressing, analysing and so on (logrotate replacement), it would > require some nontrivial configuration, something like "If size of this log > bigger then 2Mb or today is sunday. If size of this log bigger then 30 Mb, > and today is not sunday, then rotate it, and make alert". > Is there any module to parse such configuration files? I don't think there's a module for this. Those kinds of tests are fairly easy though. import datetime, os filename = 'myfile.log' if (datetime.date.today().weekday() == 0) or (os.stat(filename)[6] > 200): do.whatever() The individual tests would be better wrapped in utility functions of course. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Using python to create windows apps that everyone can use?
On 9/18/07, Thomas Harding <[EMAIL PROTECTED]> wrote: > Hi guys, sorry to post another topic on this, as I am aware that it has > already been posted a few times, but not with specifically what I am looking > for. I want an app that makes a gui interface for python (similar to > Microsoft visual studio or qt designer, not a code based one) and/ or an app > that can make this into a .exe that can be opened by any person on any > computer without python installed. For windows only, there's always Iron Python. This allows you to use Visual Studio, the commercial or the express version, to create the GUI in VB or C# and from that call Python code that does all the heavy lifting. I'd second the recommendation for QtDesigner if you want cross- platform capability. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Can a low-level programmer learn OOP?
Sorry, here's the tutorial link: http://hetland.org/writing/instant-python.html Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Can a low-level programmer learn OOP?
Chris, I can fully relate to your post. I trained as a programmer in the 80s when OOP was an accademic novelty, and didn't learn OOP untill around 2002. However now I find myself naturaly thinking in OOP terms, although I'm by no means an expert - I'm a sysadmin that writes the occasional utility. I found learning OOP with Python very easy because it has such a stripped-down and convenient syntax. The advantages of OOP aren't in performance or memory, they're in the fact that OOP simplifies the ways in which we can think about and solve a problem. OOP packages up the functionality of a program into logical units (objects) which can be written, debugged and maintained independently of the rest of the programme almost as if they were completely seperate programmes of their own, with their own data and 'user inteface' in the form of callable functions (actualy methods). Here's a realy excellent tutorial on Python that's fun to follow. Downloading and installing python, and following this tutorial will probably take about as long as it took to write your post in the first place. At the end of it you'll have a good idea how OOP works, and how Python works. Learning OOp this way is easy and painless, and what you learn about the theory and principles of OOP in Python will be transferable to C++ if you end up going in that direction. I hope this was helpful. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Creating a distro of python... What would you include in it?
On 30 May, 16:25, [EMAIL PROTECTED] wrote: > I am creating a distro of Python to be licensed as GPL am > wondering, what would anyone suggest as to 3rd party modules being put > into it (non-commercial of course!)? I know I'd put MySQLdb into it at > the very least. Any suggestions? What you put in it will depend on what it's for. Which platforms will you support? Many Linux distros already provide comprehensive package management systems, so developers on those would probably be better off using the native package manager unless you're offering something distinctive. Does your distro target a particular developer community, such as web developers, database developers or desktop developers? These communities have very different requirements, but then again if you target web developers do you include Turbo Gears, or Django or both? Do you include an ORM and if so which one? If you can clarify what you are trying to achieve, or what defiiciencies in the existing distros that you're finding limiting then that would realy help. Super-distros can definitely have a place. In fact that's exactly what TurboGears is, but it has a very clear mission statement and adds significant value of it's own. It also acts as an add-on to the standard distro rather than an alternative and I recommend you consider that strategy. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: I need some tips to begin a simple project
> PyGame is in it, right? Python comes with a basic GUI toolkit called Tk with basic stuff such as buttons, text and graphics widgets, menus, etc. PyGame is a seperate package that you can download that makes it fairly easy to create games. There are also additional libraries that make PyGame programing even easier. Having said all that, Python isn't magic. I'd recommend doing something simple first, such as a calculator or a text editor. These are very easy to do, but will cover the basics of creating a user interface, manipulating data and accessing files. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: python vs java
Aravind wrote: > hi, > > some of my friends told that python and java are similar in the idea of > platform independency. Can anyone give me an idea as i'm a newbie to java > and python but used to C++. My idea is to develop an app which can run both > in windows and linux. That's true to an extent. Both Java and Python come with extensive standard libraries, providing a useful toolkit for the programmer. Python does have a number of cross-platform GUI toolkits abailable too, including one in the standard library, although WxWidgets (formerly WxWindows) is also popular. I'd say that Python is easier to learn and more productive as a language, but Java has a much larger selection of add-ons and libraries available. I can't give you much more help without knowing what the app will do, and therefore what language features or library/framework support would be helpful. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Make Object Oriented?
I can't even vaguely concieve of how such a think could work, even at a trivial, hypothetical level. The code converter would ahve to actualy understand at a general level what the program does and how it does it, then come up with an orriginal way to solve the same problem using a different methodology. As to the simple case, even here, the converter would have to make inteligent decisions. Which methods and properties should it move to the base class, and which should it keep local? What criteria might it use for making such a choice? How could you be sure that the decisions it made would be useful or appropriate? Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Borg vs. Module
Jordan R McCoy wrote: > For example, the Twisted framework uses this technique to allow global > access to the installed reactor via import syntax, which works well > within the framework. It did, however, throw me a bit when I first > encountered it, and drove me to pour over the source to find out what > was happening. It sounds to me like this was a case of poor code commenting in Twisted (Iv'e not looked at it myself). It seems to me this is a useful trick, but like any unusual or clever bit of coding it's use should be carefully commented to make sure it's clear to anyone coming across it. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Pickle vs XML for file I/O
I've recently gone through a similar evaluation of my options for persisting data. Object serialization to pickles or XML is a very easy, quick way of persisting data but it does have drawbacks. I'm not a professional developer, so if there are errors in my analysis, I'd love to be corrected. Suppose you make some changes to the object format - adding some new attributes or properties. Suddenly your existing test data is useless. At least with XML you can edit the files by hand to add dummy data, but with pickles that's not an option and even with XML it's a painful and error prone process. Idealy you need to be able to browse and edit your saved data outside the main program, to scan for errors, fix them manualy and easily update your data structure as the application data model grows and changes. There are good reasons why relational databases are the default data store for many professional applications because you can parse and edit the data very easily using external tools. Personaly I'd go with SQLite. It's soon to be a part of the Python standard library with 2.5 and is very compact. It can be a lot more work than just serializing automaticaly, but there are toolkits such as SQLObject and SQL Alchemy that can automate this as well. Best regards, Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Paste text across multiple text boxes
This link seems to have some relevent code. http://lists.wxwidgets.org/archive/wxPython-users/msg07340.html Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: About Embedding PyWin or wxPython
Have you considered IronPython? This is of course only an option if you're prepared to code in VB.NET or C# instead of VB6 or Delphi, but it would provide seamless integratioon between your Python code and the rest of your app and would not require an external graphics library - although you would need to distribute the .NET and IronPython runtimes. Multiple-language and library integration is after all what .NET is all about. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: dicts vs classes
I'm wondering about whether to use objects in this way or dictionaries for a program I'm writing at the moment. It seems to me that unless you need some of the functionality supplied with dictionaries (len(a), has_key, etc) then simple objects are a syntacticaly cleaner and more natural way to express yourself. Any objctions to this, or pitfalls? Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Project organisation
If a particular project requires slightly different functionality from the classes in Utils.Py one way would be to import Utils.py and then either monkey-patch or subclass the classes you need to extend or modify for that project. That way you will have no effect whatever on the other projects. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: TextCtrl focus events in wxWidgets
Frank Millman wrote: > Try self.PlantCtrl.Bind(wx.EVT_KILL_FOCUS, self.OnUpdatePlantCtrl) And Voila! It works. Many, many thanks. Any idea what is going on? Simon -- http://mail.python.org/mailman/listinfo/python-list
Re: TextCtrl focus events in wxWidgets
Simon Hibbs wrote: > rony steelandt wrote: > > Since the event handler of a textctrl inherits from wxCommandEvent, > > I would guess that the binding should be to EVT_COMMAND_KILL_FOCUS > > Still not working :( I can trap EVT_TEXT_ENTER events successfuly, without using EVT_COMMAND_ENTER. This almost gets me where I want to be. The user must press 'enter' after modifying each value though. If they forget the UI isn't updated, so I'd need some way of visualy distinguishing between modified values that have been ENTER'd and those that haven't which is a pain, and not very user friendly at all. There must be some way of doing this, but blowed if I can figure it out. Simon -- http://mail.python.org/mailman/listinfo/python-list
Re: TextCtrl focus events in wxWidgets
rony steelandt wrote: > Since the event handler of a textctrl inherits from wxCommandEvent, > I would guess that the binding should be to EVT_COMMAND_KILL_FOCUS Still not working :( Simon -- http://mail.python.org/mailman/listinfo/python-list
Re: TextCtrl focus events in wxWidgets
Steve Holden wrote: > It should be quite simple: you need to handle EVT_SET_FOCUS and/or > EVT_KILL_FOCUS events (documented in the wxPython docs) to know when to > recaclulate the values. Sounds like that should be enough of a hint to you. I've tried that, but it doesn't work. Here is the test code: self.PlantCtrl = wx.TextCtrl(self, -1, "") self.Bind(wx.EVT_KILL_FOCUS, self.OnUpdatePlantCtrl, self.PlantCtrl) def OnUpdatePlantCtrl(self, event): print "set Plant" When the control loses focus, I don't get the message in the console. I'm trapping other events successfuly elsewhere using similar code. Simon Hibbs . -- http://mail.python.org/mailman/listinfo/python-list
TextCtrl focus events in wxWidgets
I have a simple form with some input values and some calculated values in TextCtrl widgets. What I would like to do is have the display update automaticaly when the user changes one of the input fields, without having to click on a 'Calculate' button. I was thinking of having an update triggered when one of the text Controlls loses focus, indicating that the user has finished changing it's value. I don't want to do an update on every character entry, as this would create a lot of bogus/meaningless updates. There doesn't seem to be such an event. Any ideas how I could implement this, or a similarly user friendly behaviour? Best regards, Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: New SourceForge project: Diet Python!!!
I was reading an article about the One Laptop Per Child initiative the other day, and being a Python fan I wondered if there are any plans to put Python on it, or at least make it available. A cut-down version of python, preferably with bindings to the Sugar GUI framework they are developing, would be a Very Good Thing. They're planning on manufacturing 100 million of these things! Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Newbie
So far I've mostly used it for writing short text file re-formatting scripts. Previously I would have used Perl, but I find Python much more readable and maintainable for this sort of thing, and only very slightly more verbose. I'm currently writing a play-by-mail game turn processing engine using Python, SQLite and wxPython. It's easily my most ambitious project so far. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Data access from multiple code modules
Bruno Desthuilliers wrote: > Separating operations on data (model/controler) from GUI code (view). > The controler(s) have a reference on the model. The views have a > reference on the controler(s), and call on the controller to get data to > display or act on data. So I instantiate a Model object that handles all IO to the database. Next I instantiate a Controller object, passing it a reference to the Data/IO model object. Next I instantiate the display panel objects for the GUI, passing them references to the Controller object. The Controller object contains the logic for all the transformations I want to perform on the data. Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Data access from multiple code modules
Bruno Desthuilliers wrote: > Do you mean the code effectively doing these operations is in the gui ? > If yes, it would be better to factor it out IMHO. The GUI has to be able to acces the data object, otherwise how does the user affect any changes to the application data? If I modify a value in a text box and hit Apply, that change must be propagated to the data model somehow. Similarly, the GUI must access the data to display it. Actualy this has nothing to do with code modules. The problem is is you have one object that contains your data, and your app consists of several objects that need to interact with it, how do these other objects access it? I'm fairly new to OOP and Python so I don't know it's scoping rules very well. Simple example: One way would be to use the database as the point of contact for all the object. Every object that wants to read or write to the database instantiates an object to interact with the database and performs whatever actions it needs. That way each top-level objecyt will contain it's own instanced database IO object. Their only point of contact with each other is the database itself. This could lead to synchronisation problems though. Another way would be to create one instance of the database IO object and then pass it as a parameter to the other application objects when they are created. The point of contact between the application objects would be the single database IO object, with the database behind it. This seems to me to be the superior approach. Are there any other architectural options that anyone could suggest? Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
Re: Data access from multiple code modules
Jeremy Jones wrote: > What does main.py do? Are you creating an instance of the gui thingy? > If so, you could just pass DataObject into your gui thingy either into > the constructor or to a setter once you create an instance of it. It's a wxPython app. I created the GUI initialy using wxGlade which gave me a small myapp.py script, a file containing the main application frame (containing a listbook controll) and several files containing panel classes. Each panel class contains controlls for performing various operations on the data set (adding records, deleting them, running various transformations). I can't say I understand how it all works at a deep level, although I've been hacking it about quite successfuly so far. Presumably if I pass DataObject through to the Frame object, and from there through to the Panel objects then presumably this will solve the probelm? I guess it would be passed by reference so all the panels would be working on the same data object? Doh! How simple. Why didn't I think of that? I'm too used to procedural scripts where you'd just put everything in a global data structure. I know this is bad, but it's hard to get out of that mentality. Many thanks, Simon Hibbs P.S. Regular reader of your blog on Oreillynet. -- http://mail.python.org/mailman/listinfo/python-list
Data access from multiple code modules
Lets say that I have an application consisting of 3 files. A main.py file, gui.py and a data.py which handles persistent data storage. Suppose data.py defines a class 'MyDB' which reads in data from a database, and main.py creates an instance of this object. How does code in gui.py access this object? Here's simplified pseudocode: MAIN.PY import gui, data DataObject = data.MyDB(blah) How do I write code in gui.py that can access DataObject? Is this entirely the wrong way to approach this sort of problem? Actualy the problem is more complex because the GUI consists of a main GUI form, and panels defined as seperate objects in seperate files. Various panels will contain controlls for manipulating data in the DataObject, or wherever data storage end up. Best regards, Simon Hibbs (who strugles to get his head round this OOP stuff sometimes). -- http://mail.python.org/mailman/listinfo/python-list
Re: listener program in Python
[EMAIL PROTECTED] wrote: > I basically want to remotely shut down windows from linux and write > such a program in python. You probably don't need to write a service in windows for this. All you need is to write your Linux python program with an SNMP library and configure the Windows box to accept SNMP calls to shut down. Frankly I'm not 100% sure how to do this. You'd have to enable the SNMP Agent on Windows, and probably the "Force shutdown from a remote system" system policy would have to be changed. The O'Reilly book "Python programming on Win32" explains how to write Windows services and do basic networking. This article explains one way: http://tinyurl.com/ezjx7 Simon Hibbs -- http://mail.python.org/mailman/listinfo/python-list
