We are having two module of same web application in Servlet/jsp. One for mobile and one for desktop. I want to redirect to mobile version whenever an handheld device hit a desktop version. Since I am having two different context of same application, which will be the best approach for this. Server side device detection or client side detection and redirection.
Thanks in advance.
This is no different than redirecting between two different applications (or even two different servers). You might have good reasons for separating it like this, but I would consider having only one application, and using responsive design (media queries) for serving device adapted content. But if you really want to do it as you describe, I would do the detection on the server side, as doing it client side would rely on being able to execute javascript on the client, which may or may not be enabled or blocked.
But whatever approach you choose, please, please, please let the user override this by his/her own wish. And when doing the redirect, please, please, please don't loose the context the user was trying to access in the first place. The worst thing I know are websites that redirect to a mobile website after trying to reach a specific part of the website (typically an article), and then just being redirected to the root of the website, and then having to try to locate the part of the website (article) I was looking for...
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We are currently looking at porting a enterprise silverlight application over to html5. The major roadblock that we have hit is the ability to open files from the user's local disk. Currently they have a document library which just links to files on their computer that they can open from within the app and view or print out. All that I read is that you can only access the local sandbox of the web app with the html5 file api's. We want to load these files from code.
Does anyone know of any workarounds to this?
Thanks
There is no way for html5 to access local file without user selection. But FSO: FileSystemObject works for IE and MAYBE could be regarded as a work around. But still there are some requirements to meet.
It is possible to use chrome's filesystem API to access files on a users local filesytem. So you'd have to be willing to make this a chrome only application.
Using java you can create a "Signed" applet which has access to the local filesystem. (if the applet is signed you can request filesystm permissions)
then there is a tutorial for accessing methods of your java code directly from javascript here: http://docs.oracle.com/javase/tutorial/deployment/applet/invokingAppletMethodsFromJavaScript.html
you should be able to perform something similar from silverlight.
There is no workaround in pure HTML5/Javascript. You need the use of plugins, such as Java or Silverlight (maybe you shouldn't port it after all). As for workarounds, HTML5 gives you an easy way drag and drop multiple files that you could transfer on the server and then display back to your users. Another workaround would be to install a custom agent (a software with only a tray icon) that would send the information about the current user "document library" to server and then again, you could display it back to the user.
Note: I've heard somewhere that browsers will eventually stop supporting plugins. http://www.howtogeek.com/179213/why-browser-plug-ins-are-going-away-and-whats-replacing-them/
Ya, I agree with Markain. However, if you were to limit your audience solely to chrome users, I daresay, you would most likely use some of your users. If Huazhihao is right, then your number of leaving customers should decrease but users who regularly use firefox won't be happy. Overall, I think that this will not work. Otherwise, there would be too many websites that trashed your hard driver (or at least wherever you have the rights to edit/delete files). I think it would be best if your product was setup to synchronize the file whenever an internet connection was detected and a change was made to the file. That way the user would not need to visit the website whenever the file was uploaded. If this is some kind of an error file, then it would be most beneficial if you were to make a link in the application that when clicked, would upload the file to the website and the website were to do whatever was necessary. If this is a purely online thing, then I don't see what business you would have looking through other peoples' files =-). Hope I helped!
I'm building a web-app that uses the device's camera and location services. The browser (I'm sticking to Chrome for now) asks the user for permission to do so on the page where the service is used.
I want the interface to be able to ask for permission at an early stage in the workflow so the pop-up dialogs don't come up during the use of the app. I know they would go away after the first visit to a page, but I want to avoid it the first time too.
Javascript is pretty much the only tool I know how to use, and I know each page has a separate Javascript execution context, so I can't get references to the objects on one page and hand them over to another.
So is there a way that will work? Maybe I need to learn some other technology?
If you need to do it in the browser, then I would suggest creating a sort of initialization page before going to the actual app page.
In the ini page you can call all permissions and download+cache all needed app scripts and also validate which permissions were accepted and not. Kinda something like when using GMail you go through their ini page first before getting to the actual GMail ui.
Once the ini page has completely loaded simply redirect to the actual app.
If you want to do it outside the browser and still use the same web technologies, take a look at Electron or NW.js.
Both tools above lets you build cross platform desktop apps with web technologies. Things like asking for camera and geolocation can be done without user permission (as I recall. not sure)
I am trying to accomplish the following:
I want a button on my website that will open a windows program on the users computer. So for example, someone clicks "Remote Desktop" on my website, and it will open mstsc.exe on the machine.
Is this possible with any language?
The way you could do this is via an URI scheme. For that to work though, your application itself needs to have an URI scheme attached to it. Examples include mailto: (opens your email client - can also be a web client such as gmail), irc: (opens Internet Relay Chat client) and an example of a truly custom URI scheme (it isn't listed in the official list) is Github's Desktop application, which uses the URI scheme github-windows:. Again, for this to work, the app itself needs to have this built into itself.
I assume you didn't make this mstsc.exe "Remote Desktop" yourself, it is impossible to start this application in any way whatsoever using just your browser. If that would indeed be possible, it would be a massive security hole. It would mean you could simply run any program (or uninstall file) you'd like.
Note: If you did indeed make the application yourself, I suggest asking another question on this site, but making it specifically about registering custom URI schemes to your application, and also specifying what language your application is written in.
I'm trying to build a projection installation for a university project, I want the audience to be able to communicate with the installation with their mobile phones.
This is what I'm trying to do:
- My Flash application will be running on a computer connected to the internet and will be connected to an XMLSocket hosted on my server.
- I need a javascript page which the audience can visit, mouse clicks (touches) will then send data from the javascript page to the socket server.
- Flash application will receive the data and so on..
Is it possible? I've been looking around for various resources, but they all require a flash app to be on the same page, which is not what I want.
I just need a standalone javascript page to be able to talk to a flash app.
Any suggestions or ideas for possible work arounds will be greatly appreciated.
Many thanks,
Will
Yes definitely possible. The server sits between the two (Flash and JS), they don't need to know each other exist. JS sends data to the server and Flash pulls it down.
I am not sure to fully understand your question.
There is no such thing as a "javascript page", javascript is a... script running in a browser environment.
In the case you want to use an Android/iPhone app environment I don't think you need javascript to do this.
But if what you want is to have a web/wap page accessible to the mobiles, with a user interface, buttons, text field, whatever, which communicates in both directions with your XML socket, you need to build your user interface in HTML, and then to use some javascript to call your XML script and translate the response in the interface. If you have a server, can't you host also your UI there? The cross-domain issue would be avoided, otherwise it's easy enough through any server-side script (PHP?).
So yes it seems very possible, but I don't see what you mean by "they all require a flash app to be on the same page". Here's what I understood: Your Flash app is not what you want to load in the mobiles, it's connected to the server's XML in/out and working fine. You just want an interface communicating with this socket. Right?
While the subject could sound like I'm looking to do something shifty, I'm not; I maintain an internal web site used by several hundred phone operators, and would like to add the following functionality:
I would like to add a control in the header of all of the web pages that would capture an image of the entire desktop and save the image as a file to a shared network drive to assist in troubleshooting production problems. This screen capture app would be called by JavaScript.
I've researched many threads on this site pertaining to capturing screenshots, and all of the offered applications don't meet my need in one of two ways:
The screen capture application has a GUI that pops up and the user sizes some sort of capture control or interacts with a window to do the capture. The users are not very computer literate, and could not be trusted with using a "pop-up" application correctly-- and it would be impossible to enforce them to save the image file with a common file naming convention. I would like the user to press a single UI control on a web site and have JavaScript make the calls to obtain a screen shot and save the image without any further user interaction.
Some automated applications save the HTML by re-posting to the site and "re-assembles" the individual HTML elements into an image. This will not work as the input data that the operator has typed in needs to be in the image, the site uses AJAX so the visual "state" of the web page will be different from one re-obtained from a POST, and some applications have had (active directory) security issues when trying to interact with our (secured) web sites.
If there isn't an application that will meet this need, I'll just roll my own control in C#. But I'd rather obtain a third-party control. so I don't have to support my own control for life. :-)
Javascript does not provide access to the local system for this functionality due to the security risk.
I believe the only way of doing this on a web page is possibly via an active X control or Java applet (similar to screencast-o-matic) but even then security may be an issue.
I also image unless your own c# control is in a windows forms application it would not work as c# controls that are part of a web site will be run on the server and not the client.
Hope this is of some help.
Well to do that you'll need something to interact with the desktop which can't be done by javascript alone.
You'll need to have an Active X Object to be able to interact with the client's machine. Once you have that, it is easy to just have the object take a picture and save it to the directory.
I believe I have the C# code to take a screen shot. If you want I'll post it.
Some alternatives to ActiveX / Java:
You can create a flash program to do the screen capture. I haven't done this and don't know the details, but I'm fairly sure it can be done.
You can setup a custom protocol for screen capture (eg. screencapture:// ), and in your header include a
Screen Capture
link. You'll need to find a gui-less screen capture program to do the actual capturing and set it up as the handler for that custom protocol.
Did it once. I couldn't find a direct way so did it rendering HTML to canvas, then canvas to image using html2canvas. Canvas to image is a much more common theme so you'll find many tutorials about.
HTML to Canvas
Canvas to image
NOTE: rendering from HTML to canvas may leave some elements behind, like SVG. But overall it did as much as expected.
PSR (problem step recorder) is a great tool for debugging purposes on client machines and it is available on all windows machines by default.
Try below and see if it works for you.
Go to Start->Run and type psr.exe (or just psr) this should open the recorder. This is fairly easy to use, so even users/clients can use it. If it works then try below steps to setup.
Step 1: Register PSR protocol. This tells the browser what to do when a link on the page is referring to PSR protocol (which we will use to open this recorder).
- Create registry values as below
HKEY_CLASSES_ROOT/
PSR/
(Default) "URL:PSR Protocol"
URL Protocol ""
shell/
open/
command/
(Default) psr.exe
If you are not comfortable with creating registry values, download and double click this file.
Use this link for more information.
Step 2: Now create an example html file to test launching PSR.
Save the below code to index.html file and open it.
<html>
<head>
<head>
</head>
<body>
Start Recording
</body>
</head>
</html>
Or download this file and open it.
This should open your PSR. It is easy to use and can record all the information you need for debugging.