I wanto to build a simple e-learning web app, allowing students to only execute/access resources directly related to the current lesson, so they can stay focused. So the idea is this web app somehow becames "the only" app the student has access to, not being even able to use the operating system (windows 8).
I wonder if this is even possible.
Thx in advance.
No, a web app CANNOT take control of a PC. If it can, there is a big security hole and it need to be fixed right away.
In your case, you don't need a web app to take control of the PC. You only need a way so that students can't easily exit the learning application. The cheapest way is to look into browser full screen mode, hide menu bar etc, so that students can only see education content. This is what older version of learning application does. However, newer browsers has too much help for user to get out of full screen mode.
Related
I find this question a couple places on the web, but never with a good answer. Let me be specific in the questions asked.
I want to build a custom Android ROM which only features one app. This app is not to interact with any hardware (per now). This app will be launched on the start up of the device. No locked-screen. The device will have to restart if the app malfunctions.
A resource told me that you can change the launcher app of the ROM.
-> Does this mean that the home screen, the one which displays all apps on our phones, is merely another app? If so, can you simply change the launcher app as it is stated here? What were to happen if this app fails?
If this is the case, it would solve the entire issue.
If not, how do you go about making this sort of project? It includes
Making an app on AOSP
Refuse users to leave the app or interact with anything else
Making this app part of the boot-up process
Remove locked screen
Make the app a dependency of the OS (to force shutdown if malfunction)
Thanks in advance for any replies
I just found Android have a topic about dedicated devices (formerly called corporate-owned single-use, or COSU) are a subset of company-owned devices that serve a specific purpose. maybe that can meet your requirement.
BTW, After into the sub-topic lock task mode that mentions about set DPC whitelist APPs and the device policy controller (DPC) needs setup by other steps.... FYR~
I looking to make a web app that has a login page and has 1 button and a image of a LED that will flash.
I started to do this in Vaadin and latest version is so big (32MB in Vaadin files) it take a long time on start on Raspberry PI.
Is there a better way?
Then the button is pressed in software or triggers from the hardware, the hardware could take 1min or more before doing it stuff and flasher LED.
Flash good
Flash's poor
Flash's bad
etc
I assume you want to run the server portion (i.e. the application server) on the Pi?
In that case, Java is not a good choice (though possible), and Vaadin certainly doesn't help as it is a server-side application framework.
Why not use a client-side solution for the UI (i.e. using Angular JS) and a python-based solution for the server-side, based on SimpleHTTPServer (https://docs.python.org/2/library/simplehttpserver.html)?
The accepted Answer by miw is correct. I'll add a bit of explanation.
Vaadin is a great tool for being able to quickly write web apps using only Java programming but rendered using regular web browser clients (no applets).
The Vaadin app actually runs on the server-side. The user-interface is rendered remotely on the client-side (web browser) but the app lives on the server and reactions to the user’s actions are executed on the server.
This server-side execution means a Vaadin web app often needs much memory, enough to maintain the current state and enable the user action-reaction executions for each user, all in the same JVM on your server. Multiplying the users means multiplying the demands upon memory and upon the CPU of the server.
Between both a JVM (Java Virtual Machine) and Vaadin, you would be placing much demands on a resource-limited computer such as Raspberry Pi. While I've not tried it, you should be able to run a relatively simple app with relatively few users. The latest Pi models with more memory (a gig) should work much better. Some competitors to the Pi come with even more memory and so might work better for Vaadin.
So, no, running a Vaadin app on a Raspberry Pi is probably not the most optimal scenario. But it would be fun to try. ;-)
I have very old Siemens CX70 in working state and just don't want to throw it out. My idea is to use its math power and peripherals (GSM module, USB, Camera and screen) to build some simple applications for home use (multichannel termometer, timer and cheap security system - for examples).
I know I should use Java ME and IDE (I love Netbeans, for example). Can you tell me what I need more to start developing? I know Java well, I just need to make an environment to developing, debug and deploy. Mobile library documentation will be very helpful too.
Thanks.
There are so many online tutorials about this topic that the only right thing to do is to refer you to google.com
Search after "getting started with j2me".
However, there's something else you should know upfront before getting too excited.
The security model in JavaME will prevent you from doing much useful stuff, in relation to some of the things you mention.
Every time you try to access certain things in the phone, like e.g. the camera, or send SMS, or read/write a file on SD card, etc etc - the phone will show a popup "This app is trying to access camera. Allow this?". And the app will only continue after a manual click on Yes.
As you can imagine, this of course renders a lot of ideas useless.
In order to prevent these popups, you can sign your app with a certificate you buy from Thawte or Verisign. But as that'll cost you $300 a year, it's not the way most sparetime hobby developers chooses.
Personally, I found another way, but it requires you to use a phone from Sony Ericsson.
Because the old Sony Ericsson phones can be patched in order to remove the Java security. After doing this on one of my old phones, I've been having fun making apps like the ones you mention. For example, an app that keeps an eye on my home when we're out, by taking a picture every second. If it detects a difference in the picture, it sends me an MMS with the picture. :-)
I have searched a long time for patching options for other brands, but I just can't find anything useful. Nokia should supposedly also be patchable, but I just can't find anything useful about it.
So in short: If you'd like to make some sparetime hobby apps on a phone like that, you should either find a Sony Ericsson phone and patch it - or go dig up an old used Android device.
Good luck.
i need to develop in java an application that accesses local resources, mainly a webcam, and possibly a wacom bamboo pen tablet. It should take pictures and notes and then post them to a web server.
The ways i can think of are:
use applets
use some kind of standalone app created via JavaFx (or swing or similar)
Which way would you go about it? Are applets considered a viable/secure way to achieve this?
Thanks
I would go the standalone app route. I always turn Java off in my browsers because I can never remember which specific version has security bugs.
If you build it as a desktop app I think you could quite easily convert it to be an applet later on if you wanted.
I have read the Blackberry documentation and it is possible to push a notification from a webapp. I am planning to create a Blackberry application that compliments to our webapps. But I am still left in the middle whether to develop a webapp or native Blackberry app. I have also look at how a webapp runs on Blackberry browser and it looks smooth.
From your experience does the native app offer something that the webapp doesn't? Bonus question, is Facebook and Twitter app on Blackberry a native app or a webapp? If it is a webapp, is it possible to make a launcher for the application on Blackberry?
Thanks for your help.
Facebook and Twitter are on both types. The web apps are just a website formatted for a small screen so anything you do in say asp.net will show on a blackberry web app if you program it to. The native app just feels like part of my phone. You can save data on the phone so if your app is a relating to news or something that would be stored I can read it offline or slow connectivity (camping, rural areas, etc...). It can also interact with other feature that blackberry offers such as contacts, email, media player, etc...
If you would like to save anything for the user to view without pinging the internet a native app would be preferred.
It's possible to create a launcher but I haven't created one so I'm not sure of the details. I would assume it's just an app that opens the browser to your URL.
One more thing about a web app would be if your application stores users settings (twitter auth key, etc...) they would need to be stored on your server and not the users phone adding more expense and maintenance.
Good Luck.
Widget is not supported for device software less than 5 , you combine both of web and native development by using browser field ,but you need to consider that its Java Script support is poor
Let's not forget that the blackberry browser is really bad as well. I don't know any BB users who would want to use a web application because of that.
When it comes to native apps, you have some choice however and you are not restricted to java (depending on which OS version you want to target). In addition to the mentioned Java, you can use Widget (link for resources) that behaves like a native app, but can be accessed like a web app.
I was just at innoTech and they had a whole session on this topic. But instead of recaping it let me just post the funny video they showed at the end which sums it all up.
Mobile Dev Rap Battle: Native Code vs. Web Apps