I was presented with a Python logic and a GUI written in C++ Qt and asked to combine them. Before I choose the route of re-implementing the GUI in e.g. PySide, I would like to know which way would be the smoothest to achieve such a combination. Would I rather make the C++ GUI available to the Python logic (and a controlling layer) or the other way around?
I will gladly provide more information, if necessary. My problem is a lack of experience in that matter and that there are so many solutions of how to make code of one language accessible to the other, that I feel a bit smothered in options.
In this case, the Python logic is actually just a (too large, but that's another topic) class which provides some signal processing methods.
This is a crisp rephrasing of a prior question, which I somewhat clumsily posed, and therefore missed its aim.
We are in the process of standing up a UI on top of a python system. This is all throw away code, so we want something quick, yet presentable.
We will have a couple of "interfaces" but they will be of two types. One will be control, it will basically be sitting on top of a python thread, and accepting requests from the user.
The other will be more of a display screen that will need to be able to display images, and some classic "grid views" of text to the user.
We pretty much know we could* do all of this in HTML but wasn't sure what would be the best way to interact with the core python code?
Anyone know of a good UI python presentation layer? Since we know we can do all of this in HTML/Jquery pretty quickly, we are also open to suggestions on how to integrate this with a web server..
Any suggestions? Really interested in finding out if there is any way to use python as the back end to a webserver.
Let me know if you all need more information.
I like wxPython. The demo application is excellent and lets you browse, tweak and re-run the code right in the demo.
We have found the DJango meets our needs. It is a pretty slick mvc style python web stack. Really is easy to use, and very quick to develop in. I will say that the ORM layer is a little young so it is hard to do some simple queries, but luckly since this is throw away code we can just use native sql.
Tkinter is probably going to be the solution you can use quickest. Its API is simple and straight-forward, and you probably already have it installed.
As the other 2 classic Python GUI options have been given already, I feel duty bound to suggest PyQt :)
Using QT Designer I've found it much simpler than TKInter to get some basic GUIs up and running. Build your GUI up in a WYSIWYG way, then hook it up to the back-end logic. I've also found that the large amount of C++ help on QT available on the interent usually translates more or less directly across to PyQt. The resources available for TKInter are IMO pretty obtuse, and simply stop as soon as you want to do anything more interesting than Hello World. YMMV.
The Rapid GUI Programming with Python and QT book is a fantastic resource. Had me programming real applications in no time.
I am not sure if my question title makes sense to you or not. I am seeing many cool applications which have cool animations/effects. I would like to learn how to use python to create this kind of GUI applications under Linux.
"cool animation/effects" like 3D wall in Cooliris which is written in flash and compiz effects with opengl.
I also heard of some python GUI library like wxPython and pyQT. Since I am completely new to python GUI programming, can anyone suggest me where to start and what I should learn to achieve and create such application? maybe learn pyQT with openGL feature? pyopengl binding? I have no clue on where to start. thank you very much for your time and suggestion.
By the way, in case if someone need to know which kind of application I am going to create, well, just any kind of applications. maybe photo explorer with 3D wall, maybe IM client, maybe facebook client etc...
http://techbase.kde.org/Development/Languages/Python
Many KDE styles use SVG and plenty of animation. The user can always change themes. I think you should be more specific about what kind of animations you want to do. I don't think 3D wall type affects really fall into the widget category that QT is. It sounds to me like you want to make a 3D interface for an application. If that is the case, you may want to look more into 3D engine type libraries used mainly in games. I know that some have excellent GUI widgets for programming game menus and the like. I guess you'd decide on your engine and the see if there are python language bindings. One of my favorite engines: http://irrlicht.sourceforge.net/links.html
Another thing you would want to consider is how you want to handle the window management. Do you want to make a full screen interface? Or is to to be windowed? Also how would such an application integrate into a 3D window manager or rather a window manager with compositing.
Edit:
In that case the qtopengl module is probably something to look into: http://doc.qt.nokia.com/4.6/qtopengl.html
I do recommend QT. It's clean and easy to use and cross platform. So your app could run on windows as well.
One thing you'd want to think about before hand is the type of FX you want to perform. For example, if you want to create a page curl type effect when renaming the image, you'd have to think about how to program that, or look for libraries/code snipets that do that math. 3D engines that are used in games often have a lot of support for those kind of typical FX or animations that you'd see in a game. If you use something like qtopengl, you'd need to think about this as well. qtopengl can pretty much only render. Think of it as a viewport. However, it is the correct approach to making a 3D application for the desktop.
Programming 3D applications is really interesting and fun. I enjoyed it a lot. However, don't get discouraged be the math. I recommend getting a book about it if you are serious. I liked this one: http://www.amazon.com/Primer-Graphics-Development-Wordware-Library/dp/1556229119
However, IIRC the examples are C++ which you may not be comfortable with. When you understand such mathematical concepts, it easier to think about how you would make a page curl type affect. Of course, if you find libraries or code that shows you how to do the math, that may be fine.
May be, just create a GUI and all effects will make compiz?
Anyway, as I know QT have ability to use openGL.
http://doc.qt.nokia.com/4.1/examples.html#opengl-examples
I am a linux (mostly ubuntu) user with a reasonable understanding of how the system works (although I am certainly not a linux guru!). In the past I have developed small cross-platform desktop applications in python/GTK and I delivered them to clients as self-contained filetrees, so that the only dependencies were Python itself and GTK.
Now I would like to develop a small applet for ubuntu, that I would like to release under GPL 2 or 3.
In particular these are the new steps I know I must learn in order to achieve my goal (it is very possible there are a few more that I am unaware of, though!):
Integrating with gnome: I want my application to be available as an applet in the taskbar.
Using D-bus: In particular I want my applet to use the new osd-notification framework for ubuntu, but communication with other applets is also a possible feature for a second iteration.
Packaging: I would like to setup a public PPA as soon as the application will reach alpha stage, but I also would like to use dependencies from existing packages in the official repos, rather than include the libraries again in my own package.
Of course official documentation will be my first source of knowledge, but - basing my judgment on the very useful answers that I received on another topic here on SO - I decided to turn to the SO community to collect additional advice like for example:
Are there additional steps to those I outlined before, that I have to learn in order to be able to implement my project?
Based on your own experience, would you advise me to learn those steps in advance (as the knowledge of those will influence my way of coding the core functionality) or would you consider integration with gnome / d-bus and packaging as "higher encapsulating levels" that can be added on top of core functionality afterwards (note: D-bus will be used at first just for pushing data. Input data will be retrieved with a webservice)?
Would you advise me to separate my application in two packages (back-end and front-end) or to keep it together in a single package?,
Do you know of any useful resource that you would advise me to look at, for learning any of the things that I have to?
Are you aware of any common "beginner's mistakes" that I should be aware of?
These questions are not meant to be exhaustive, though: if you feel that I am missing something from the general picture, you are more than welcomed to point me in the right direction!
PS: Should I have failed in explaining my final goal, take a look at project hamster: what I want to achieve is similar in terms of user interface (meaning: the applet should display the status and clicking on it should open the application itself, from which you could both configure the applet and perform various operations).
Well, you list python, so you'll want to have pynotify in your arsenal. It wraps DBus, and gives you a direct api for manipulating the osd-notification system.
>>> import pynotify
>>> pynotify.init("Lil' Applet")
True
>>> note = pynotify.Notification(
... pynotify.get_app_name(),
... "Lil' Applet wants you to know something's up.",
... "/usr/share/icons/Human/48x48/status/dialog-information.png")
>>> note.show()
True
This displays a notification that looks like this:
[ ] **Lil' Applet**
[ICON]
[ ] Lil' Applet wants you to know something's up.
As you already know, your first and best friend will be the code written by others - copy, paste, dissect, understand.
Luckily there are a few projects that do what you intend to achieve.
I can recommend conduit's code as a prime reference how to do things in a clean fashion. I think they also have stuff on dbus. Others to keep an eye on, would be deskbar-applet, hamster (heh), and any other app you remember having feature X. Sometimes it might require some C code deciphering though (like the applet button bit - i suggest you better take it from hamster as i was having some major time getting the thing straight)
Then the "devhelp" app will be of great assistance - it allows you to read and search in man pages fast and easy. Make sure that you also have the -doc packages for all the modules you intend to use.
For user interface i strongly suggest using glade, as that will allow you to change interface later much easier. Where you can't use glade - add and alignment box and add the widget in the box in the code.
There certainly will be quirks and things that you will learn the hard way. Should not be too hard though!
The packaging, especially the autotools will be bit of a struggle, but you will get it right. For how to do debians (and from there to PPA), you can dig in the hamster's repository history. There was once a "debian" folder.
I would suggest to start small - see if you can get a window. Then put a button on it.
You don't have to do it "right" the first time. For first time it will be ok, if something works at all.
As for the separation - i would not bother about it until you get there. Splitting up into two parts and have a core, should not be too hard later. But that all depends on your priorities.
Last thing - getting friends who know the field helps too. And one way to get new friends, is by taking part in other projects, heh.
There are some very good recommendations here already, but let me suggest that you develop your applet not so much "for Ubuntu" as "for Gnome". It doesn't take much extra effort to also make RPM packages for distributions such as Fedora, and Arch Linux packages, to name two examples. There is one major disadvantage though -- to stay compatible with Debian stable you have to stick to ancient versions of GTK and GLib, or at least make any functionality depending on newer versions optional. It's painful, but apparently Debian stable users appreciate it.
I'd also suggest setting up a source code management system somewhere as early as possible. You may not be worried about your disk crashing, but sometimes it saves you a lot of trouble just to be able to revert everything you did since the last commit.
Here's the link to the documentation on the official Gnome Panel Applet library. I don't know if it has Python bindings or not.
When I asked this question two years ago Ubuntu and Gnome were much closer to each other than they are today. At present (end of 2011) gnome adopted the gnome-shell, while Canonical decided to develop their very own UI (unity)...
Part of the tension that brought to the split specifically involved libappindicator, which makes the way I formulated this question (and probably part of the answers) obsolete.
Besides, there is now AskUbuntu on stack exchange, that would probably be a much better forum to ask about ubuntu-specific question.
I have been trying to make a case for using Python at my work. We use C# and ASP.NET for basically all of our development. 80% or more of our projects are web applications. It seems natural that we would look at some of the nice dynamic web languages (Ruby, Python, etc), and with things like IronRuby and IronPython, I started seriously investigating.
I love Python. It's a beautiful, expressive language. It's a joy to code in, for sure. The multitude of python modules and frameworks make it very appealing. Problem is, I cannot think of any specific problems, any specific hurdles that would require a language like Python. ASP.NET gives us RAD, it gives us a full-featured framework and all that good stuff. Also, we all already know C# and have lots of projects in C#, learning a new language just because doesn't quite work.
Can you guys help me think of something to finally convince my boss to really learn Python and start using it on projects?
Edit: I know that no problem requires only one language, I just meant, are there any specific problems in which dynamic languages excel over static languages.
Edit again: Let me also mention that my boss prompted ME to investigate this. He has put aside hours to research these languages, find a good one, learn it, and then figure out how we can use it. I'm at the last step here, I do not need a lecture on why I should consider my motivation for changing something my company does because they do it for a reason.
"Can you guys help me think of something to finally convince my boss to really learn Python and start using it on projects?"
Nope.
Nothing succeeds like success. Use Python. Be successful. Make people jealous.
When asked why you're successful, you can talk about Python. Not before.
Choose projects wisely: things where a dynamic language has significant advantages. Things where the requirements are not nailed down in detail. Things like data transformations, log-file scraping, and super-sophisticated replacements for BAT files.
Use Python to get started doing something useful while everyone else is standing around trying to get enough business and domain information to launch a project to develop a complicated MVC design.
Edit: Some Python to the Rescue stories.
Exploratory Programming
Tooling to build test cases
What's Central Here?
Control-Break Reporting
One More Cool Thing About Python Is...
In Praise of Serialization
And that's just me.
Edit: "boss prompted ME to investigate", "figure out how we can use it" changes everything.
The "finally convince my boss to really learn Python" is misleading. You aren't swimming upstream. See How Do I Make the Business Case for Python for the "convince my boss" problem. The edit says you're past this phase.
Dynamic languages offer flexibility. Exploit that. My two sets of examples above are two areas where flexibility matters.
Requirements aren't totally nailed down. With a dynamic language, you can get started. Rework won't be a deal-breaker. With Java (and C++ and C#) you are reluctant to tackle devastating design changes because it's hard to break everything and get it to compile and work again. In Python, devastating changes aren't as expensive.
Design is in flux because you can't pick components. You can write Wrappers and Facades very easily in Python. It's a scripting language. And, Python modules compose into larger aggregates very simply.
Coding is in flux because requirements and design keep changing. It's scripted -- not compiled. You just make a change to the code and you're off and running. Testing is easier because the work cycle is shorter. It isn't code-compile-build-test it's code-test.
Testing is in flux because the requirements keep changing. Same as above. The work cycle is shorter and faster.
Almost no problem requires a specific programming language, that's just not how things work.
The easiest way to get a new language into an environment like yours is to start a new work project in your own time in the new language. Make it do something you need doing, and write it on your own time. Use it yourself, and other people will probably notice it. They then say "Can you send me that program?" and boom, they're using your new language.
If you really want to something, I would probably write a site in Django, simply because its admin interface blows everyone away.
The main point to remember is that if you start using python, that's one more thing everyone else has to learn, and it's another bullet point that will need to be on every prospective employee's resume. That can get expensive, and management won't like it.
Sneaking a language in is often done by automating tedious manual tasks (especially dynamic/scripting languages like Python/Ruby etc). Set it up so something like deploying builds, or shuffling backups, or whatever is done with Python.
Then casually slip in how easy it was to do, and try to spread some of the enthusiasm around.
Acceptance and awareness should slowly grow from that, and before you know it, management is seriously considering Python for a new project.
Can you guys help me think of
something to finally convince my boss
to really learn Python and start using
it on projects?
Unfortunately, the answer is no. As Harley said, no problem is going to require a specific language. The approach Harley suggested is also a good one. Learn on your time, build an useful app on your time, and maybe, just maybe, someone at your work will want to use it, like it, love it, then want to learn more about it.
Another approach you could take is to get a better understanding of why your company uses .Net (therefore, Windows Server, and probably SQL server) for nearly all development. Once you have a good understanding of why they aren't open to other languages, then you have some fire power to build a business case for the "why not?".
Why pay licensing costs when you have tools that can accomplish the same things? There are free alternatives out there, like Python, that run on free servers.
Why not give your team the chance to grow their professional tool-belt? This is my opinion, but a good developer is a developer that isn't afraid to learn new ways of doing the same thing they've done before.
But, in the end, I wouldn't get your hopes up. Bottom line, it costs money to introduce a new language/environment into an IT shop. Whether it's software, training, or employee rollover, there is a business reason behind utilizing a single language for a company, and sticking to it.
I'm in the exact scenario you're in. I work in a .Net shop, and that's not going to change any time soon. I get by, by working on my own projects in my "free" time. I enjoy it, and it makes for a good balance.
Hope this helps.
Take a step back, and look at your approach. "I know what I want the answer to be, but I can't find any evidence to support it."
Despite the fact that Python is my current first choice language, I am afraid I find myself on the side of your boss! Sorry.
I think you should open your mind and consider all the options from the stance of your organisation's best interest, and see if you don't come to a different conclusion about the best language.
There are many factors in the choice of language, and how pretty it is is a fairly minor one. The availability of staff is a key one. The cost of retraining, availability of the libraries and meta-tools, performance, etc. etc.
Once you have taken into consideration all the different factors (and not just "Oooh! It'd be fun!") and made a balanced assessment (rather than a predetermined answer), you may find that your boss is more willing to listen.
p.s. The suggestion to secretly use Python for work code, and leaving the company with a terrible code debt in a language they are not prepared for seems very unprofessional to me.
The best leverage you're likely going to have is tools and libraries; as others have pointed out, no language is required to solve any particular program. So let's look at Things You Can Leverage Using Python:
Google App Engine
SciPy
pywinauto
django
Those are off the top of my head; finding what's applicable to your team and your company is left as an exercise for the questioner :)
Well, here's a view of why Python programmers make better Java programmers; the concepts are much the same as for your situation.
Essentially, people who learn a language because they want to show that they enjoy programming, like to learn new things, and are more likely to think outside the box.
...if a company chooses to write
its software in a comparatively
esoteric language, they'll be able to
hire better programmers, because
they'll attract only those who cared
enough to learn it. And for
programmers the paradox is even more
pronounced: the language to learn, if
you want to get a good job, is a
language that people don't learn
merely to get a job.
Not only that, but Python enforces "good looking" code and you don't have to do the whole code/compile routine. With IronPython, you can simply code in Python and use it as is; just another .NET tool.
Python got a good start in the Java world as Jython for unit testing. In fact many Java people started using it first that way. Its dynamic scripting nature makes it a great fit for unit tests. Just yesterday I was wishing I could use it or something like it for the unit tests I was writing for a VB.Net project. I'd have to say that it isn't so much about the individual language IronRuby or IronPython as it is about the style of development that they enable. You can write static language like code in either but you don't fully reap the benefits until you can start to think dynamically. Once you grasp those concepts you'll start to slowly change the way you code and your projects will require less classes and less code to implement. Testing, particularly unit tests will become a must since you give up the warm blanket known as a compiler with type safety checks for other efficiencies.
The language is almost never the key to success. Good programmers can be successful in a variety of languages, and you'll find successful projects in almost any language. You won't find the failures that much because those projects just go away never to be heard of again. If you're looking for a new language because you don't have good programmers, even the best language in the world isn't going to help.
And, you haven't said anything about the sort of work you're doing. Python might be a good choice because it has well-supported and widely-used libraries that are critical for you. On the other hand, C# might have better support for the stuff that you want to do. A tool outside of context has no intrinsic merit. You might love screwdrivers, but that doesn't help you row a boat.
If you want to use Python, or any other language, just because you like it, be honest with yourself and those around you. It looks like you've made a decision to switch, don't know why you are switching, and now need to rationalize it with reasons that had nothing to do with your desire to switch. If you had a good reason, you wouldn't be asking here :)
That's not entirely a bad thing, though. Programming is a human enterprise. If the programmers (at whatever level) insanely love a particular language, no matter how stupid the reason, they are probably going to produce more. It's just not a technological solution though.
Good luck, :)
I am pretty sure (100%) that you don't need to use Python for MS Windows at least.
In cases of other platforms you can use any language you like.