I understand GObject started out as part of gtk+ and was later separated from the GUI related elements. What I would like to know is: it used outside gtk+ ? what about other desktop environments, and other OSs like Windows or Mac OS? Are there any prominent examples of such cases?
There are some things here and there that use GObject without GTK+, but AFAIK they are few and far between.
I'm guessing that the most prominent ones right now are Clutter-based projects (it's a graphics-oriented UI library). There are also a small number of projects based on libgnt (text-based UI library), and possibly various non-GTK+ programs written in Vala (a C#-like programming language with GObject-based classes).
Edit: Also GStreamer (thanks liberforce!), which is a popular multimedia library. The vast majority of GStreamer projects also use GTK+, but I'm sure there are some non-GTK+ ones.
Related
I am curious to know if there is any kind of programming library/framework for the C language for cross-platform programming of course. I mean there are already frameworks like Wxwidgets, Boost, Qt, U++ and etc for C++ available but I have not yet found any for C .
Updated Info:
We are trying to build an underlying Framework/library to be used in our project. We are going to eliminate the dotnet and instead provide a counterpart for those libraries which is fast and less demanding.
We will be working on a server/client based project, and thus the underlying services must be fast and also portable. GUI is not our priority now, but libraries providing threading capabilities is of importance to us.
And for the ANSI part, I think we are fine with that at the moment unless something changes that in the future.
if you write plain ANSI C, it should work on every POSIX system.
The most successful example of cross platform C library is standard C library itself (IMHO).
If you're looking for GUI toolkit GTK is the answer,
if you're looking for terminal UI, ncurses is pretty portable.
If you're looking for general use libraries, as long as they're written in ANSI C, should work almost everywhere, as long as it doesn't use system level APIs.
Can you just tell us, what kind of library/framework you are looking for ?
GTK+ is long established and actively maintained cross-platform C-only (or primarily) toolkit. You'll find not only on-line documentation but also books written about it. It is the framework backing up the GNOME project.
GTK+ is meant to build applications with UI, first of all. However, even if you don't need UI you'll find that some GTK+ components, namely GLib, provide general multiplatform support comparable with Qt. Actually, I needed a framework without UI at first and chose GLib over APR because I was able to find documentation and tutorials easier.
GTK+ was initially developed on UN*X an X-Windows which remains the platform where you can get it running the most easily. I wouldn't say that it is more difficult on Windows; it is just that you have more compiling environment options. I started with prepared GTK+ packages and MinGW but ended up integrating GTK+ with MSVC.
GTK+ exists for a long time and some people may find it old-school. On the other hand, it shows that it has proven to be stable and useful. There are also bindings for C++ and C#.
As with every big framework, the more you need from it the longer you will have to learn. But the other way round it works too; the more you learn the more you'll be able to do with it. Consistent coding style helps getting used to it.
--- Ferda
We can use databases sqlite,mysql etc with python and qt.But i dont know which database is used in gtk and how to use it.can anybody help me to find the database for gtk and also give some example for HOW TO USE IT (i am beginner).
GTK+, or the GIMP Toolkit, is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, but it is not a programming language itself. It is written in C but has been designed from the ground up to support a wide range of languages, not only C/C++. Using GTK+ from languages such as Perl and Python (especially in combination with the Glade GUI builder) provides an effective method of rapid application development, therefor you can use any of the technologies you wrote.
As ergosys said, GTK favors no database API. You can use what you want.
Is it possible to write system level source code in Vala.
like for a small Micro kernel OS?
or for use it in the Linux kernel for modules or device drivers?
Technically, yes, but in reality it's probably not very practical.
People have written kernel modules in Vala before, but AFAIK nothing really serious. Actually, someone wrote a Multiboot kernel using Vala a few years ago.
You can get around the dependency on GLib by using the posix profile (pass --profile posix), but it tends to be a bit buggy and lots of features aren't supported, including a lot of the stuff that makes programming in Vala a pleasant experience.
I don't think so. Vala is tied to the GObject and Glib gtype type system (inside GTK) - including its reference count based memory management. The Linux kernel uses a different (even if conceptually similar) memory management. And inside your microkernel OS, you need to provide one.
Some update to the answers above: the posix profile has been deleted from vala codebase in version 0.17.4, because it was unmaintained. Here is the announcement.
I'm moving away from strict Android development and wanting to create iPhone applications. My understanding is that I can code the backend of iOS applications in C/C++ and also that I can use the NDK to include C/C++ code in Android apps. My question however is how? I've googled quite a bit and I can't find any clear and concise answers.
When looking at sample code for the NDK, it seems that all the function names etc. are Android (or at least Java) specific and so I would not be able to use this C/C++ backend to develop an iPhone frontend?
I'd appreciate some clarification on this issue and if at all available some code to help me out? (even just a simple Hello World that reads a string from a C/C++ file and displays it in an iOS and Android app).
Thanks guys
Chris
Note that I almost exclusively work on "business/utility/productivity" applications; things that rely heavily on fairly standard UI elements and expect to integrate well with their platform. This answer reflects that. See Mitch Lindgren's comment to Shaggy Frog's answer for good comments for game developers, who have a completely different situation.
I believe #Shaggy Frog is incorrect here. If you have effective, tested code in C++, there is no reason not to share it between Android and iPhone, and I've worked on projects that do just that and it can be very successful. There are dangers that should be avoided, however.
Most critically, be careful of "lowest common denominator." Self-contained, algorithmic code, shares very well. Complex frameworks that manage threads, talk on the network, or otherwise interact with the OS are more challenging to do in a way that doesn't force you to break the paradigms of the platform and shoot for the LCD that works equally badly on all platforms. In particular, I recommend writing your networking code using the platform's frameworks. This often requires a "sandwich" approach where the top layer is platform-specific and the very bottom layer is platform-specific, and the middle is portable. This is a very good thing if designed carefully.
Thread management and timers should also be done using the platform's frameworks. In particular, Java uses threads heavily, while iOS typically relies on its runloop to avoid threads. When iOS does use threads, GCD is strongly preferred. Again, the solution here is to isolate the truly portable algorithms, and let platform-specific code manage how it gets called.
If you have a complex, existing framework that is heavily threaded and has a lot of network or UI code spread throughout it, then sharing it may be difficult, but my recommendation still would be to look for ways to refactor it rather than rewrite it.
As an iOS and Mac developer who works extensively with cross-platform code shared on Linux, Windows and Android, I can say that Android is by far the most annoying of the platforms to share with (Windows used to hold this distinction, but Android blew it away). Android has had the most cases where it is not wise to share code. But there are still many opportunities for code reuse and they should be pursued.
While the sentiment is sound (you are following the policy of Don't Repeat Yourself), it's only pragmatic if what you can share that code in an efficient manner. In this case, it's not really possible to have a "write once" approach to cross-platform development where the code for two platforms needs to be written in different languages (C/C++/Obj-C on iPhone, Java for Android).
You'll be better off writing two different codebases in this case (in two different languages). Word of advice: don't write your Java code like it's C++, or your C++ code like it's Java. I worked at a company a number of years ago who had a product they "ported" from Java to C++, and they didn't write the C++ code like it was C++, and it caused all sorts of problems, not to mention being hard to read.
Writing a shared code base is really practical in this situation. There is some overhead to setting up and keeping it organized, but the major benefits are these 1) reduce the amount of code by sharing common functionality 2) Sharing bug fixes to the common code base. I'm currently aware of two routes that I'm considering for a project - use the native c/c++ (gains in speed at the expense of losing garbage collection and setting targets per processor) or use monodroid/monotouch which provide c# bindings for each os's platform functionality (I'm uncertain of how mature this is.)
If I was writing a game using 3d I'd definitely use approach #1.
I posted this same answer to a similar question but I think it's relevant so...
I use BatteryTech for my platform-abstraction stuff and my project structure looks like this:
On my PC:
gamename - contains just the common code
gamename-android - holds mostly BatteryTech's android-specific code and Android config, builders point to gamename project for common code
gamename-win32 - Just for building out to Windows, uses code from gamename project
On my Mac:
gamename - contains just the common code
gamename-ios - The iPhone/iPad build, imports common code
gamename-osx - The OSX native build. imports common code.
And I use SVN to share between my PC and Mac. My only real problems are when I add classes to the common codebase in Windows and then update on the mac to pull them down from SVN. XCode doesn't have a way to automatically add them to the project without scripts, so I have to pull them in manually each time, which is a pain but isn't the end of the world.
All of this stuff comes with BatteryTech so it's easy to figure out once you get it.
Besides using C/C++ share so lib.
If to develop cross-platform apps like game, suggest use mono-based framework like Unity3D.
Else if to develop business apps which require native UI and want to share business logic code cross mobile platforms, I suggest use Lua embedded engine as client business logic center.
The client UI is still native and get best UI performance. i.e Java on Android and ObjectC on iOS etc.
The logic is shared with same Lua scripts for all platform.
So the Lua layer is similar as client services (compare to server side services).
-- Anderson Mao, 2013-03-28
Though I don't use these myself as most of the stuff I write won't port well, I would recommend using something like Appcelerator or Red Foundry to build basic applications that can then be created natively on either platform. In these cases, you're not writing objective-c or java, you use some kind of intermediary. Note that if you move outside the box they've confined you to, you'll need to write your own code closer to the metal.
What are the disadvantages of the Tk module compared to other solutions to create a GUI in Perl?
I toured the various gui modules for Perl recently, and here is my summary (disclaimer: ultimately I found that none of the existing modules met my needs so I started writing my own gui toolkit).
Tk - Decent to work with and the interface is very perlish. The gui itself is a bit dated looking, and doesnt take advantage of any of the operating system's native widgets (like filepickers). On most systems it will require a C compiler to install.
Wx - Difficult to work with, un-perlish interface. Large programs almost require a gui builder to keep track of everything. Support for os level widgets is mixed. Nicer looking than Tk IMO. Compilation is involved, requires installing several libraries, can be difficult to get running on windows. The assembly of programs is very procedural, and does not map cleanly to what the program will actually look like.
Qt - last I looked this module was more or less abandoned and only supports Qt3. I didn't try to install it, but i imagine it needs a compiler.
Prima - Similar to Tk it has a dated appearance. Requires a compiler.
W32::GUI - I ruled this out early since it is not cross platform.
XUL::Node / POE::XUL::Node - rather heavy dependency tree that includes C code. Seems unmaintained and I had mixed experiences getting it to install. Windows was a no go, OSX was a no go, it had limited functionality on OpenSUSE. It also only supports a subset of the XUL language.
I found that none of the existing gui toolkits made it easy enough to distribute your application to end users. It is ok to expect programmers to jump through the hoops of resolving library dependencies and compiling code, but end users aren't going to do that. So the first requirement I had was to be pure Perl.
Secondly, nearly all of the existing gui toolkits force you to work in a very procedural manner: Create a container. Create a packer for the container. Create an object. Set properties on that object. Add the object to the packer. Run the packer to fill the container object. Repeat.
Instead, I find that nested design (like HTML) is easier to follow for two reasons. First off, since objects are nested, there is no need to name everything (label_456, label_457...). Secondly, the structure of the program mirrors the structure of what is displayed.
So I started work on XUL::Gui, and its been coming along rather well. It is pure Perl, and only depends on core modules for ease of installation. It has one external requirement, which is that a recent (3+) copy of Firefox is installed. It uses the familiar design pattern of web development with nested tags styled with CSS. It is certainly at a level where you could write fully featured single window applications with it.
Hopefully this helps you to figure out which toolkit is best for your project.
Tk has not been developed in a very long time. ActiveState now recommends development with their Tkx toolkit, which provides a thin layer over TclTk. It means that themed widgets are possible. But, TclTk is still quite primitive compared with many other GUI toolkits.
I haven't tried XUL:Gui but it seems the way to go.