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Is there any way to recognise pen pressure using javascript.
Preferably I don't want to make any use of Flash and try get this done as pure JS.
EDIT: okay I realised that it is kind of possible for Wacom tablets as they come with software that can work with their javascript api to make it possible (demos). But it's no good for people with Trust tablets or any other brand... So no good really.
Any body know how to do it in C# if not JS?
Yes - if the user has a Wacom tablet installed, then their browser will have a plugin for it that you can access. http://www.wacomeng.com/web/index.html
edit from author: I wrote this a very long time ago. Please see the comments below
Microsoft implemented something called Pointer Events in IE 11. It allows you to access pressure property along with stuff like pen tilt and size of contact geometry.
So far it only works on IE11 (and IE10 with vendor prefixes) but there is a W3C candidate recommendation so maybe it will be standard in future.
Javascript as a programming language in itself has no more ability or lack of ability to read this kind of data than any other language.
The language isn't important. What is important are the APIs available to you from within the language.
Javascript can be run in a number of different environments, some of which may possibly have access to APIs for this kind of hardware. However most Javascript is run in a web browser environment, and this is clearly what you mean.
The web browser environment provides a number of APIs. The most obvious is the DOM, which gives you the ability to manipulate the page, etc. There are other APIs available in the browser as well though. For example, the Geolocation API.
All these are standard APIs which have been defined by the W3C (or in some cases are in the process of being defined by the W3C), meaning that all browsers that support them should make them work the same way.
Unfortunately for you there isn't a standard API for working with pressure pads, so the direct answer to your question is no, it can't be done.
Whether one will become available in the future remains to be seen, but I have my doubts.
There is one way that you can do it though: ActiveX.
ActiveX is an API provided by Microsoft in older versions of IE. It basically provides a way of accessing virtually any Windows DLL code from within the browser.
Since the pressure pen device driver for Windows will be provided as a DLL, this means you should theoretically be able to access it in the browser via an ActiveX control. So therefore yes, you would be able to program it using Javascript.
The bad news, though, is that this is not something I'd recommend. ActiveX as a browser-based technology has long since been abandoned, due to the massive security holes it caused. I don't think the latest versions of IE even support it (I hope not, anyway), which means you'd be forced to use old versions of IE (and only IE - no other browser ever supported it) in order to run your code. Not ideal.
No, that's not possible. Probably not even with Flash.
You can only do so in an Native app. Javascript does not have access to pen pressure information
Does compliance to WCAG 2.0 AA prevent the use of JavaScript?
My understanding based on Understanding Conformance is that we can still use JavaScript as long as we don't generate any content that is noncompliant and that we explicitly state we support JavaScript. Is that correct?
The short answer is, no, it doesn't. Your understanding is pretty much correct.
Indeed, you can use JavaScript as long as we you abide by WCAG 2.0 success criteria :-)
There is a rationale why you may have heard JavaScript is banished from accessible content. In the old days of WCAG 1.0, it practically censured the use of any content generated by JavaScript. You needed to check that your web application still worked with JavaScript disabled, which practically restricted JavaScript to decorative purposes. Otherwise, you ought to provide an alternate, non-JavaScript reliant, version, which usually involved a lot of server-side magic (try and see Google Maps without JS to understand what I mean).
This was because in those old days assistive technologies and even some mainstream browsers (e.g. mobile) did not support JavaScript, or browsers did not expose script-generated contents.
This is not the case anymore. You can use JavaScript in accessible, WCAG 2.0, websites, but:
Get acquainted with WCAG 2.0 criteria and make sure you are not failing any of them. It is not a matter of using one or another technology, but a matter of using them correctly.
In particular, check you abide by the client-side scripting techniques for WCAG 2.0 which deal with recommended and disapproved scripting usages.
Use ARIA Techniques for WCAG 2.0 to define the semantics of non-standard controls, they are widely supported by major browsers.
A slightly longer answer is that pages can require JavaScript (AKA ECMAScript), but it's better if they don't. Use JavaScript sparingly and carefully. There's a set of guidelines for using JavaScript on WCAG 2.0 compliant pages.
You can use JavaScript. It is not a problem so long as all semantics are provided (name, state, and role) and you manage the focus accessible. Use ARIA when you need to provide semantics or manage focus.
I want to program my xhtml Web Applications without javascript.
What are the alternatives for creating interactive xhtml web applications?
Perhaps java applets which do the tasks of javascript?
Or is there another way?
Thanks for any help!
Javascript is hard to debug, is dynamically typed, strange OOP, could be replaced by any other language when that language will be cut to work at a browser.
I would also like some typesafety in my code what can discover many bugs before running the code.
--EDIT 2--
Have a look at http://www.scala-js.org/.
---EDIT---
So for now there is no real alternative to javascript what is as flexible, widespread and applicable.
What i think is applicable are frameworks/tools who compile one language to another like GWT or coffescript.
Thank you for the detailed answers. The reason for my question was, that web development is getting more complex every day. I prefer languages like Java for stable error outlining and type safety. JavaScript on the other hand is (in my opinion) mysterious in its ways and hard to debug (browser incompatibilities, silent errors, unintuitive operands, dynamic typing,....). I developed Websites with JS for years now and it feels horrible to me due to such debugging problems and code management. Yet the libraries are quite powerful and ease much of the work.
To have an interactive site you need something that can execute code on the client machine.
This is (at the moment) usually JavaScript. In the past this would have also included Flash or Silverlight (both of which are now on the wane).
JavaScript has a big advantage in that it can easily manipulate the HTML elements directly. While it is possible to do that with Silverlight it's not as easy as Silverlight is designed primarily to build self-contained objects.
Google Web Toolkit GWT lets you write java code which compiles to client-side xhtml+javascript. It relinquishes the page-based standard web approach for a more desktop-like interaction (if I remember correctly the API is somewhat similar to many desktop windowing toolkits).
You may (but don't have to) also develop the (java) server logic and have some client-server communication baked in for you by the compiler.
Have a look at http://code.google.com/intl/it-IT/webtoolkit/
Some JavaScript alternatives:
Flash
Silverlight
Java applets
This is not a recommendation, just a list.
If you're really that allergic to JavaScript, there are a number of frameworks that let you write server-side code which generates the JS for you, as other answers mention.
Check out Google Dart - it has reached 1.0 recently, and has started standardization process few days ago (ECMA TC52). It also compatible with currently available browser via highly optimizing dart2js translator, so you can start using it right now :). Much more sane language than JavaScript, IMO.
More can find more information on the official page here: https://www.dartlang.org/ (tools, documentation, sample code, tutorials), and there is also nice introductory video on the YouTube: http://www.youtube.com/watch?v=FqsU3TbUw_s.
As well as applets you have Adobe Flash, Microsoft Silverlight, shortly Chrome NACL. None of these interact with the HTML DOM as seamlessly as JavaScript though.
One thing you can do is simply have the server-side code do all of the processing. You limit yourself to having only CSS available for interactivity, but you can still do just about everything by loading a new page.
If you're considering java applets, then I guess it's necessary to mention Flash and Silverlight (*).
Of course, there are "interactive" web applications that don't use javascript... they use postback. But I don't think this is what you mean.
If you want to target just Internet Explorer, you can use VBScript (Microsoft's proprietary javascript) or even ActiveX. But I doubt that's what you mean, too.
So the onus is on you to answer — why not javascript?
(*) I guess.
I'd be very interested to know what your reasons are for not wanting to use Javascript? The answer to that question will make a big difference to how your question should be answered.
The Javascript language is actually quite powerful. Yes, it does have some quirks, but so do all other languages. A lot of the perceived "problems" with Javascript development in the browser are actually people having issues with the DOM rather than Javascript itself. The DOM, on the other hand is where a lot of the shortcomings and the cross browser issues crop up.
If this is where your problems lie, then you may be better off using a Javascript library such as JQuery, which abstracts away a lot of the direct access to the DOM, and resolves a lot of the cross-browser issues.
If you're using the latest browsers, a lot of the simple effects that previously required Javascript can now be done using CSS. drop-down menus, tabsets, fading, rotation and transition effects. All of this can be done with CSS. However most of them are quite new, and not available in all browsers currently in common use, so you would be better off sticking to Javascript for at least some of them for the time being. Even when they are ready for mainstream use, you'll still need some Javascript to hook them all together.
If you do really have a burning desire to develop using a language other than Javascript, then as you already pointed out, there are other options for programming on the web, such as Java applets. There's also ActiveX controls, Flash and Silverlight, and a few others. However none of them are universally available to all users in the way that Javascript is.
All of them require browser plug-ins of one sort or another, and all of them have issues with users who don't want to install them or corporate environments that don't allow them to be installed. In the case of technologies like ActiveX, they may only be available on certain browsers and operating systems, and (again like ActiveX) they often have security issues.
The only real reason that most of these other technologies existed in the first place was to fill a gap in the capabilities of the browsers at the time. All of these capability issues have now been resolved -- with HTML5 and related technologies driven by Javascript, Flash and Silverlight have been rendered obsolete; ActiveX controls were considered obsolete long ago; and when was the last time you saw a Java applet in mainstream use?
The bottom line is that the browser world is moving very rapidly away from any client-side code other than Javascript, and there are very good reasons for that.
Use pyjamas (google it), you can write normal python code and have it compiled as javascript so you get the best of both worlds, the power and expressiveness of python and the ubiquity of javascript.
Also keep an eye on the Falcon project by Adobe, it's an experimental compiler which translates actionscript 3 (a very powerful language compared to plain javascript) and the flex framework to javascript.
You can also try GWT by Google, where java is used as the client side building code (and yes, it also gets compiled to native javascript).
If it runs on the client's computer and can modify the DOM, it can work. JavaScript is the most widely supported so it'll work out-of-the-box for many people.
Basically, anything which functions like JavaScript can replace it.
Flash can perform basically everything that JavaScript can (graphically, but it can't modify the DOM), but if the user doesn't have Flash Player installed, you're out of luck.
Java can also work, but the same concept applies: if the user doesn't have JRE (or a similar machine)
Silverlight is similar to Flash, but much less supported (I can barely get it to work on my Linux box)
Just curious: why are you looking to replace JavaScript with something else?
This may seem inane, but I actually like using jQuery much better than JavaScript. It makes event handling and Ajax very simple.
I am a non-web programmer, but I am getting now more interested in web technologies.
I know that HTML and JavaScript are today the fundamental technologies for web applications, but it also seems that actually they were not created strictly for that. (HTML was created for web pages, JavaScript to make them a bit dynamic). Does it have any significant negative impact on how advanced web applications are created today? What are the limitations?
Do you predict any new technology to emerge in 5-10 years to replace HTML+JavaScript? If yes, then what it will be like?
Though HTML and JavaScript may seem old, there is nothing inherently problematic about building complex applications with them. The larger "problems" web applications must deal with have to do with the nature of the world wide web: the inconsistency of network communication and the statelessness of HTTP.
In the first 10 years of the web, the differences between (and shortcomings of) various web browsers was so vast as to confound attempts at building complex applications. Many technologies emerged for building so-called rich Internet applications which circumvented the browser entirely. These include (most notably) Java applets, Macromedia/Adobe Flash, and Microsoft Silverlight. Since they require browser plugins to be installed, the are not optimal for general purpose web applications and, in my opinion, they will be long outlasted by HTML.
In the the past five years, the lives of web developers have become significantly easier. Browsers are paying more attention to the W3C's recommendations, JavaScript is implemented consistently in all major browsers (more or less; the DOM is still frightening), and HTML 5 promises many new features (font management, video/audio embedding, geolocation, asynchronous page updates, etc) which will make pure HTML web app development even easier.
It seems unlikely that anything will emerge in the next decade that will "replace" HTML because there is nothing fundamentally wrong with it. JavaScript...very possible, but it's hard to know with what, and at the moment JavaScript is only getting stronger.
The biggest difference between web and non-web application programming is the constantly-changing platform on which web software runs. If anything is going to change dramatically in the next 10 years it is this. People are going to be accessing the web on everything in 10 years, and keeping up with the different platforms will always be a concern. This is simply the nature of web programming.
My advice: spend 2 hours per week reading about new web technologies. This will keep you in the loop so you know how to plan for what's coming. The web is pretty unpredictable. I don't think there's any such thing as an application that will last for 5 years without major changes. The best you can do is to stay informed, and react quickly.
Several technologies have already emerged that have tried to conquer this famous duo, including....
Java applets (RIP)
ActiveX (RIP)
Macromedia Shockwave (RIP)
Flash
Silverlight
If you're doing research about this on your own, the search phrase to look for is RIA - Rich Internet Application.
The problem with these new technologies is that ultimately they end up requiring some sort of platform-specific binary in order to view and interact with. In the case of Flash and Silverlight, the developer needs to learn an additional web language to create them.
I think the fact remains that plain text wins again (except in edge cases).
On the horizon is the infamous 2022 HTML5. That should be interesting.
It is highly unlikely that anything will emerge in the next few years that will upset the base of HTML + Javascript for RIAs simply because of the trouble with getting everyone on the alternate platform. If another technology were to supplant HTML + Javascript it would either come about through (ordered from least to most likely):
Platform Changes
Hardware (and software)
Software [browser]
.
Browser updates
Introduction of a new technology within the main browser, a la IE's behaviors
Plugins for browsers
Platform changes are unlikely because they require a paradigm shift in either the "gadget" or the "browser" marketplace. Unless there is massive demand for something new that supplants everything that could be done the old way backwards compatibility will need to be maintained.
As an example of a paradigm shift in the gadget and the browser markets, consider what would happen if next year a hardware breakthrough makes it possible to create completely immersive 3-D environments that turn your brain into a plug-and-play device and the languages used to program on its realspace browser it are Lisp variants.
As for a paradigm shift in the browser -- this is also unlikely because it would require, for backwards compatibility, that browser manufacturers support two (or in IE's case 5) rendering engines until the new methods completely fazed out the old methods. Unless the new method was vastly superior to the old method it is doubtless that this would gain any traction.
Imagine, if you will, that IE decides that YAML is a better format for sending data over the wire and sets up a new standard for marking up data and events in YAML. Safari in the meantime figures out how to sandbox a C like language in their browser making it possible for developers to do literally anything they want to if their users will let them.
[Part II coming after work]
What you will find more and more obvious is the use of XML and JSON for data and communication between client and server applications. You hear about it, somewhat, with all the Ajax conversations but that is what Ajax is. That involves javascript which doesn't appear to be going away any time soon. Other languages output js where needed and frequently that's to handle XML or JSON. HTML is there to activate the browser so the next big thing that's already here is more Javascript and XML/JSON with HTML5 wrapped around that for the browser.
Perhaps I'm just unaware of the competitors, but it seems when it comes to client-side scripting in the browser and DOM, Javascript is it. I know there's VBScript, but it really isn't even in the same ballpark as JS (not even cross platform, for starters).
I'm just curious about how this came to be. Surely there would be a general desire for a new language to replace Javascript: built from scratch to do all the things Javascript has been bent and moulded into these days (look at the reliance on JS Libraries).
Momentum. JavaScript has been around for 15 or so years, and browser manufacturers have worked for 15 or so years to make it work in their browsers.
If a competitor came along, it would need to really bring something new to the table in order to convince everyone to a) adopt it, b) live with locking out all the users of older browsers like IE7, Firefox 3.0, Chrome 1.0 etc. and c) find replacements for all existing libraries like jQuery, prototype, extJS etc.
In short: we don't need another Standard, let's rather improve JavaScript and build on the rich foundation that already exists instead of starting back from stone age again.
There is! Ones that spring to mind are Flash, ActiveX, and Java... But these all have their drawbacks. Mainly security and integration with the browser/DOM.
Flash and Java live in their own little world, by design (and to address security issues). They can't alter the HTML around them. ActiveX has access to the DOM, but also everything else on your computer.
JavaScript seems to have found a nice balance between flexibility and security, it can trivially interact and alter the pages HTML/CSS, do "safe" networking, has a decent standard library (which has things like JSON, XmlHttpRequest'sih networking, DOM manipulation, and so on). Most importantly, it's available in basically all vaguely-modern browsers, on all platforms, in a consistent manner (compared to CSS)
There are problems with JavaScript, but nothing major. The biggest is the performance. Load a comment page on Digg and watch your CPU usage. Chance are it will be 100% of one CPU core. There are projects to improve this, like SquirrelFish, TraceMonkey, and other strangely named things. But the performance is adequate to do some extremely impressive things (Google Spreadsheet, for example).
Basically, JavaScript is great, and it's drawbacks aren't nearly as big as the other competitors.
JavaScript won because it was introduced by Netscape in the period when they had above 90% percent market share. IE and other browsers had no choice but to support it also.
If a new language should be introduced, it would have to be either by agreement between all major browser vendors, or in a period where a single browser have enough market share to push it through.
Microsoft could probably have pulled it off some years ago when IE has an extremely large market share (before the rise of Firefox and Safari), but they chose instead (for strategic reasons) to let the browser stagnate.
Today, a new language would require agreement between at least Mozilla, IE and Safari to gain traction, and I think that is highly unlikely. The browser vendors have invested a lot of ressources in optimization, compatibility testing and so on for JavaScript - why should they want to start from scratch with a totally new language - and have to support two languages in parallel for decades to come? The cost greatly outweights any benefits.
Anyway, it is quite unrealistic to believe that a new language designed from scratch could be significantly better than JavaScript.
Show me another language that isn't reliant on libraries?
C, C++, C#, VBs, ... all rely on libraries. The only difference is that they often come with a standard set of libraries.
So do we really want is a standard set of libraries? What we're currently getting is a range of library sets (JQuery, prototype, extjs, mootools, etc). This is a good thing since we the developers get to choose one that suits our needs. In addition these libraries can be included and evolved without changes to the client-side component.
I can think of no compelling language feature missing from Javascript. By compelling I mean so earth shatteringly important that I'd be willing to alienate those browsers that do not support it.
Standardized (ECMA-262)
Common syntax and relatively simple to master
Good browser support
Extendable
Still being developed
Relatively quick based on how much data it needs to process sometimes.
If a good competitor had arrived before 1999 (ECMAScript 3), it would probably be a tie between those two.
There are other languages for client side scripting, but AFAIK, none are integrated into a browser.
Both Flash and Silverlight have their own Languages. Flash has ActionScript, while Silverlight has many and all that work under the DLR including Python and Ruby.
To your second point as to why, more specifically you mention reliance on JS libraries as a flaw in the language; Libraries are popular, not because the language if broken, but because the standard API is broken. The existence of such great libs builds on the power of the language.
There is nothing particularly wrong with JavaScript, it has some features that up to very recently would have been esoteric or academic. First class functions for example.
Also, ubiquity / mass existing runtime deployment is a very compelling feature. ;)
I recommend you to view Douglas Crockford’s presentation about “The JavaScript Programming Language” to learn about the history of JavaScript.
I think Javascript (ECMAScript) with its C like syntax is so popular for some of the reasons C is:
Relatively small number of language
keywords (easier to learn).
Concise and efficient syntax (quick to write).
Easily extendable
through external libraries and APIs that do
not pollute the basic language (ie Browser DOM,FilesystemObject etc).
Creating a new language that will provide many of the current libraries "built-in" is always risky as it starts to limit future applicability of the language and makes learning the base language harder.
This would be even more problematic for a client side browser language because the language designers can't possibly know how the language may be used in the future.
I think Javascript the language is fine in its current role as the "glue" that links so many other client sode technologies.
There are no other competitors because while Javascript is not perfect, it does the job.
I guess because the demand for it would have to be huge for browsers to implement it.
After all, it's the browsers that process and run the JavaScript and you'd have to have a large amount of sites using the language in order to make the browsers interested in implementing it. Then again no-one would use it if there was no browser support in the first place.
i'd say that this is because client side web development is still a very young branch of programming.
if you look at it only now it has become more widespread since we moved to faster "intertubes" :) and we're not using modems anymore.
and the problem for clent based web development is that it's not up to the developer what platform he'll use but it depends on the browser manufacturers.
and they change slow.
VB script's demise was in my opinion its VB-innes. too much unnecessary stuff.
As for javascript it will mature, but it's a start.
Browser support. If its not an MS tech the it most likely will not go into IE. If it's not in IE then no one can use it. If it is an MS tech, then most likely only IE will have the right to use it as it will be closed source and proprietary. If only IE supports it then only some developers will use it.
To challenge JavaScript it must work just as easily and more consistently across all of the major web browsers. Without browser support any new client side web tech is destined to fail.
I think it has to do with standardization, because durring the last browser-war (ie v. netscape) there were two, Netscape's ECMA (+1 Geek point for you if you knew this was the real name for JavaScript) and Microsoft's JScript, obviously ECMA (JavaScript) won out and became the defacto standard.
Now, we have another browser-war in progress and each of the 2 (3 if you count Chrome 12% FFS) major competitors 3 fully (with a few edge-cases) support JavaScript.
My guess is that its ubiquity and ease of integration in any new user agent project. It comes built into almost all browsers so you dont have to download/install/configure anything to have it running. once you look at user agents off desktops (wii, iphone, windows mobile, n95 etc) the availability of any of the contendes dries up quick - so you code for html and javascript becuase it will work most of the time.
I agree with Michael, we should improve Javascript, not worry about competitors because there aren't going to be any, in fact even Javascript 2.0 seems so far from reaching reality.
Since Javascript is such an ambiguous language, we're able to create libraries (jQuery) and even abstractions (Objective-J) and not worry about all the problems that Javascript has at its heart.
After so many years we don't even have CSS implemented same in all the browser, same goes for the JavaScript, IE has one model and rest of browsers has another Model (I mean like Event Handlers and attaching events).
If new competitor comes, it has no chance, neither it has so much time as css and javascript had.