I'm building an application using xlib/x11. What can I do to make sure the application is accessible and usable by people using screen readers and other assistive technology? Is there documentation/standards about this stuff somewhere?
I'm building an application using xlib/x11.
Don't do that (coding just above X11 an accessible application). Raw Xlib is too low-level. (You'll need to work many years if you only use Xlib, and by that time X11 could become obsolete, e.g. replaced with Wayland).
You really want to use some toolkit like Qt or GTK, etc; not just Xlib.... Life is too short to avoid toolkits (which are built above Xlib and other things). See also EWMH
And both Qt and Gnome (above GTK) have accessibility guidelines and features. Read about Qt accessibility and about Gnome/GTK accessibility. So choose some toolkit providing accessibility features and use them.
Or consider developing a web application, perhaps by using some HTTP server library like libonion. Web accessibility is also well documented.
If you really want to only use Xlib (without any toolkit), you need to implement accessibility yourself (probably with some other software). That (and developing your own widgets...) will take you a lot of time (years of work), if you don't take advantage of existing software and guidelines related to accessibility.
Related
So far I have only been developing desktop applications using C++ or C#.
Now I am considering building a local standalone application using a browser GUI. The application would be similar to something I could e.g. build with C#. It should have local database access and offer some limited image editing (line drawing, polygon filling) and user defined, clickable graphical elements (basically polygons the user draws).
The application should not be web or server based. The application will also not be very complex.
The main thought behind this is to have the GUI be OS independent and as platform independent as possible.
Is that feasible? Or should I go about something as Swing, SWT or Java FX (which I have just read about)?
What programming language should I use for the application (Java, Python, ...)?
Are there toolkits for a programming language you recommend that offer an abstraction layer from OS specific stuff like file system handling?
Are there toolkits or tools that would help me in creating the browser GUI?
Well you can use c++ for this :) and for your GUI use OpenGL, and then you can use glut... You can take a look at OpenGL superbible book, it mostly about 3D drawing, but there is also something about gui... and it comes with examples for linux, windows, mac... basicly it is OS independent...
I worked mainly in web development but occasionally do some C/C++ or Java programming. I am very curious how these frameworks actually produce the graphics used in their GUI. Were the GUI elements (title bar, window frame, status bar, buttons, etc...) designed by a designer in Photoshop then a developer adds that graphic to the framework? Or do the developers actually build the elements programatically with the direction of a designer?
If someone could give me an overview that would be awesome!
Great question, Lark ! Since we're in Qt Framework branch, I'll tell you how its done in Qt, but I'm sure you can apply to similar frameworks or libraries like GTK, etc.
So Qt started a framework that would provide one API for a variety of platforms making it very easy to port your applications from one platform to another while providing native look and feel on those platform. So for example on MacOSX a push button would have this blue Aqua style while on Windows XP it would look like a button on Windows platform. Trolltech put a lot of effort and did a great job on making the GUI look native. So how it works ? Well, all Qt widgets use QStyle and its derivatives to render themselves. Depending on the style, a widget would look differently. All the standard widgets follow the guides of those platforms they are designed for. There are probably some small graphics designer work behind that, but I believe its not that significant. The main source of the look and feel is the platform guides that describe how UI elements on those platforms should look like and their behavior.
But Qt has been developing very fast and the trolls came with a very promising technology called Qt Quick. Its an amazing technology which allows designers and developers tightly work together providing the best UI. Its highly oriented on using artwork made in Photoshop, GIMP or similar tools in the code. And its much easier to use mock ups from designers with Qt Quick than with C++/Qt cause Qt Quick is initially designed for that.
Hope that helps
The basic low level functionality of most GUI frameworks is quite old, the result of a great deal of very hard work by earlier developers working with primitives - literally drawing things on terminal screens, etc, at very low levels, using C or Assembler. Slowly, libraries for abstraction of these processes, and frameworks and class hierarchies for refining them and organizing come into being. All Linux GUI's (in fact, nearly all contemporary GUI frameworks) are based on XWindows, for example:
X originated at the Massachusetts Institute of Technology (MIT) in
1984. The protocol version has been X11 since September 1987....X primarily defines protocol and graphics primitives - it deliberately
contains no specification for application user-interface design, such
as button, menu, or window title-bar styles. Instead, application
software – such as window managers, GUI widget toolkits and desktop
environments, or application-specific graphical user interfaces –
define and provide such details. As a result, there is no typical X
interface and several different desktop environments have become
popular among users.
See more there, for some good information about this topic.
What GUI toolkit does Valve use for Steam? Is it Qt? I am interested in using the same toolkit for a project.
According to Valve itself:
"VGUI is Valve's proprietary Graphical User Interface. All Source and Steam applications use VGUI to draw windows, dialogs and menus. It also handles localization: the displaying of text in the user's preferred language. "
That's interesting, maybe if you guys do some research you can have it working in your programming language. I'll download the SDK to see if I can make it work with Java :)
http://developer.valvesoftware.com/wiki/VGUI_Documentation
Having had experience with the Source engine I know that Valve have an library called VGUI which they use for all their games and many of their tools (when in game the library sits on top of the Source renderer, when in tools it sits on top of the Windows API I believe). Although I can’t answer the question with 100% certainty I suspect that this is what they use for Steam as well (I seem to recall some Steam updates that mentioned VGUI) – I would be surprised if the new beta uses a different library.
Even if it is not using VGUI, given what I know of Valve I would think they will have written something else entirely in-house.
So, it is (almost certainly) proprietary and highly unlikely to ever be available for third party use (unless you have the funds to buy a Source engine license).
Steam only runs on Windows and predates QT for Windows, so I'd have to guess something else.
Since Steam has had the same GUI since 2003, chances are it uses some variant of MFC. It also uses an embedded Internet Explorer web browser for its Store and Community sections.
However, I can't give any guarantees about what the version currently in Beta uses. It looks quite a bit different and includs the Webkit rendering engine instead of using IE. It may use Webkit for everything rather than drawing their own GUIs.
Does this answer the question?
http://games.slashdot.org/story/10/02/25/0640233/Steam-UI-Update-Beta-Drops-IE-Rendering-For-WebKit
I am working on a new small utility desktop application but I am not really able to choose the GUI framework to use. I have worked on both JAVA,C# and C++, so language is not really a constraint. My criteria are:-
A very well designed architecture, something like QT. It's better if it follows typical C++ design methodologies.
Layout management should be easy, intuitive and not really cumbersome. I hate adjusting pixels on screen.
Its license should be open.
It should look good :)
Mentioned QT seems to comply to all your requirements. QT has "deploy everywhere" attribute, whilst Java needs no deploying at all (it depends on what is use of your utility).
Ad. 2 QT has really convenient GUI designer.
Ad. 3 LGPL. Usually it is enough.
Ad. 4 It is always matter of taste. IMO QT4 looks awesome under linux, but it's windows look'n'feel is correct at best. It's strong point is, that without additional tweaks it almost everywhere looks native.
I've been using Swing, and it works fine. NetBeans (a decent IDE by itself) even supports graphical GUI building.
It's well designed (basically
everything is done with listeners,
functions that are registered for a
certain event). It has bindings, so
you don't have to write code to set
up a value in a text field or read
it out
Layout is not perfect, but
acceptable within NetBeans. It's
WYSIWYG (almost). Look-and-feel can
be changed on the fly.
License is free. Source-code is not
available, I think.
Looks fine on Windows and Linux,
less so on OSX.
You could always try SWT. The advantages of Java with the standard L&F of supported operating systems.
Well designed. Lots of
documentation, and very easy to
develop with. (If you know Swing,
you can pick up SWT in no time.)
I believe layout managers do exist
that support SWT. I'm not positive
about this though, as I typically
don't use layout managers too much.
Uses the Eclipse Public
License. Should meet most of
your requirements.
From Wikipedia on SWT:
SWT is written in Java. To display GUI elements, the SWT implementation accesses the native GUI libraries of the operating system using JNI (Java Native Interface) in a manner that is similar to those programs written using operating system-specific APIs. Programs that call SWT are portable, but the implementation of the toolkit, despite the fact that it is written in Java, is unique for each platform.
Hope that helps you.
I'd suggest wxWidgets if you want to program in C++ or wxPython (the python language binding of wxWidgets if you know or don't mind learning Python.
Architecture is similar to QT I think.
Layout using sizers. Quite easy once you get the hang of it.
Liberal open source license.
Widgets are native on all platforms (Windows, Mac OS X, Linux).
Some of the requirements (restrictions) for such a ui framework/toolkit are:
No single vendor lock down
Ability for real time data visualization
Good initial widgets
Good dash boarding capabilities
cross platform
Good development/debug environment
No flash
It's a pity you can't/won't use Flash. Else I could really recommend Adobe AIR. It has a good editor (Flex Builder built on Eclipse), a good component framework with many out of the box components, charting components set, ability to communicate with many different protocols (and you could write your own protocol implementation), cross platform, runs in the AIR runtime and not in the browser, file IO, ...
I wouldn't pass over Flex/Air (Flash) without a closer consideration but here are a few others I have come across:
wxWidgets
GTK+
Qt
There is also a slashdot post with links to some tookits I haven't heard of. I'll add their recommendations here:
GLUI, an OpenGL-based GUI
Whisper, a Mac/Windows application framework
WxWindows, a framework which supports Windows 3.1/95/98/NT, and Unix with GTK/Motif/Lesstif, and MacOS
YAAF, Yet Another Application Framework, offering suport for Macintosh OS, Windows 95 and Windows NT, and X Windows
CPLAT, a framework for developing MacOS and Windows (Linux soon) applications
Ardi's Carbonless Copies technology, which is a portable rewrite of much of the MacOS API
For general information:
GUI Toolkit/Framework Page
PIGUI FAQ Page
C++ User's Journal PIGUI Page
I might suggest Mozilla XUL, but it has some drawbacks:
No really good development / debug environment (although there are tools and debuggers; they are variable)
You are locked into a vendor, but it is Mozilla.
It is very easy to use though and allows you to reuse your web Javascript skills for a rich-client app.
There's also Java of course. It satifies all your requirements AFAICS.
Plenty of custom charting controls, which are things you will struggle to find for GTK/WxWindows/$other_small_userbase_framework.
If you dont like Swing(its come a long way - Metal is dead, long live SystemDefault L&F!), there are options like SWT or even QT bindings for java(QTJambi).
For C or C++ go QT, its APIs are really nice.
For RCAs check out Eclipse RCP. For RIAs, you might be interested in OpenLaszlo. It's a rich internet platform that can compile both to Flash and DHTML.
http://www.gnustep.org/
"GNUstep is a cross-platform, object-oriented framework for desktop application development. Based on the OpenStep specification originally created by NeXT (now Apple), GNUstep enables developers to rapidly build sophisticated software by employing a large library of reusable software components."
Portable to: Windows, BSD-based systems, Linux-based systems, HP/UX, , Solaris, Sparc, GNUstep Solaris 10 U2 vmware appliance, OpenSolaris, others.
I recently made a pretty complete list here: http://commadot.com/ria-frameworks/
ExtJS is probably my favorite and we use that at work. I think it satisfies your list. Otherwise, there are a bunch of other possibilities on that page.