I am planning on creating my own POS system by using pos for .net.
So far i have never created any POS system or used pos for .net. I was trying to find some tutorials but wasn't successfull, does anybody know some good website or book? I am also wondering if there is a way to emulate the pos devices (like barcode scanner....)
Using windows embedded 8 industry
As your base system and the POS .net you will be able to achieve what you are trying to do.
As mentioned by #CResults most barcode readers are plug and play. So unless they need to have com ports mapped you will not have to do anything to them. They scan decode and then send the values like a keyboard
Receipt printers are the issue. You can either use the windows driver to print to the printer (highly buggy) or every receipt printer you can communicate directly too through a Com port. You will need to ask for the SDK from the manufacture. This way you are communicating direct to the printer rather then relying a mediator that could crash or freeze.
But the time you are going to spend building your project there are plenty of already created ones. It would be worth while to use a system that has already been developed on for years. Rather then re-invent the wheel.
Check out Bepoz http://bepoz.com/ They have been around for a while and have a very solid application.
Disclaimer: Employee of Bepoz
I believe the SDK comes with plenty of sample code and documentation.
There's also a community forum:
http://social.msdn.microsoft.com/Forums/en-US/posfordotnet/threads
To answer part of your question most barcode scanners appear to the OS as keyboards, sending their output (the decoded value of the barcode) to your app as a string of characters.
So to emulate all you need do is capture the keyboard.
Related
I have developed a Client/Server application for IM with Qt. So far messages are sent and displayed at the client side, but when the program is closed the messages are no longer available since a proper storage is missing.
I would like to keep the messages on the client devices and avoid to store everything on the server. I don't want to use a DB either since it needs to be installed and I would like to keep everything quite easy.
Therefore I was thinking of simply storing everything in an encrypted file, but I couldn't think of a proper format to do that.
Has anyone experience with that or any suggestions how to save the messages from different clients?
You do have a concern with data integrity in face of unplanned termination of your software, due to bugs in your code, transient hardware errors, power outages, etc. That's the problem that everyone using "plain files" usually ignores, as it's a hard problem to solve and requires extensive testing and know-how.
That's why you should use an embedded database. It will solve that, and many other problems as well. SQLite is a de-facto standard for applications such as yours. You can add any encryption you wish, as SQLite provides hooks that let you implement writing and reading of the pages. You'd do the encryption there.
One little-appreciated aspect of SQLite specifically is the amount of testing it gets during development. The test harness, most of it non-public, is probably worth way more than the published SQLite code (>1M USD). SQLite is used in aerospace applications, e.g. IIRC in code classified as DAL-B under DO-178B.
what's the proper way to capture biometric information (pressure, speed...) by signing with a stylus on a canvas developed in a JSP web Page
Alright, since no one else has attempted to answer this question, I shall elaborate on my comment and opefully it will serve as an answer to others as well.
First, Java Server Pages (JSP) is a server-side language. It is meant to run on the web-server and not on the user's browser. The same goes for other server-side languages like PHP and ASP.
So a server-side language is not able to directly interact with devices (keyboard, scanners, cameras, etc). Only when the data is submitted by the browser or client program, the server receives it for processing.
For a device to receive input, there are two key pieces of software needed.
The device driver: which must be installed on the user's machine
The application program to capture inputs and do any processing.
If either one is missing, the device cannot function. And then there's another issues. Depending on the device, there's various feedback from the driver/API that should go back to the application that reads it. For example, if a fingerprint scan was not very successful for some reason, the scanner should tell this to the user. So again, there's the need for interactivity between the device and the user's application.
Thus, using any server-side language is out of the question for such applicatoins.
Now, in order to make this possible, you may use a client-side program. Here are some options.
A native application in VB, C/C++, Pascal or other language. If this is an option, the user must install this application on their computer.
A browser-based program. This can be a program created using JAVA (not Javascript or JSP), or ActiveX component. ActiveX is largely OS/browser dependent. And the TRUTH is that even Java is not truly platform independent when it comes to different operating systems. There are some technical differences that you'll need to look into. But for the most part of interactivity and high-level operations, yes, Java is more platform-independent than the others. But on a personal note, Java is my worst language. I try not to use it anywhere anymore. That's a different story.
In both options above, every client machine must have their own proprietory drivers and often some sort of API for browser integration.
A year or so ago, I had to program a Bio-Mini fingerprint scanner using VB. It was all sweet in the beginning. Then due to the restrictions of networkability and concurrent usage, the drivers/SDK could not take the load and things were going wrong. By the way, the drivers/SDK were meant for MS-Access. Knowing that the DB was the problem, I started to port this to MySQL. And it was a severe climb from there. I had to do a near-rewrite of the SDK for capturing and comparing data using arrays in VB. And to make things worst, the device was changed and things went wrong again. But do note that the new device was from the same manufacturer.
So keep in mind that even a simple change like that can cause a problem.
I am making a tangible controller for Spotify (like the one from Jordi Parra, http://vimeo.com/21387481#at=0) using an Arduino microcontroller.
I have a Processing sketch running which does all the calculations with the data from the Arduino. I want this Processing sketch to be able to control different options in Spotify like: Next, Previous, Play/Pause, Volume Up/Down, Shuffle.
Right now I use an extra Arduino Leonardo which simulates key presses while AutoHotKey listens to those and sends them to Spotify. It does not work very well and I only have limited options.
I would love to get rid of that extra Arduino while getting more control.
I am working on a Windows thing so Apple script won't work (for me).
Is there a possibility to control the Spotify app from Processing? Or is it possible to use the library to create a new Spotify app in Processing?
Many thanks in advance!
Paul
Disclaimer: I work at Spotify
Right now there is no cross-platform way to control the Spotify application. On Linux, Spotify will respond to dbus commands, which means that a bit of hacking could send play/pause/next/previous. I have heard that it is also possible to control Spotify on Mac OSX via applescript, but I'm not 100% certain about this. A quick google search for "control spotify mac os x applescript" produced some interesting results, though I'm not sure how current or relevant any of them are. As for Windows, I'm not sure if/how one would control the application at all.
Otherwise, your best bet would be libspotify, for which you would need to write a Processing library to communicate with it. Based on a bit of quick research, it seems that Processing libraries are written in Java, which means you'd either need to use a wrapper such as jlibspotify or hand-roll your own JNI wrapper for libspotify.
I'm not sure how current jlibspotify is, given that they are wrapping a rather old version of the library. If you do any libspotify hacking it is better done in C/C++ with a minimal JNI wrapper, but all of this may be way more work than you are intending for this project.
Why not utilize Spotify's keyboard integration.
The Arduino Leonardo supports USB HID mode.
So, send the keyboard keys for Next, Previous, Play/Pause, Volume Up/Down, Shuffle.
Most everything has a single bound global key. I believe only shuffle does not. You could create a global hotkey in your OS to bind to the app's shuffle control key.
If you are looking for status feedback on the state of each button, this of course won't help you.
Good luck.
When using the networking API in BB OS 5.0 (ConnectionFactory, etc.) there are a ton of options for configuring the connection. How much of this is it appropriate/expected to expose to the end user of the application?
Certainly, I will be setting what I think are appropriate defaults for my application, but some things (e.g. preferred and disallowed transports) seem like they are questions that the user can or should answer.
Is there any kind of best practice here?
Yes, this is one of the things I dislike in BB development - you never know what type of connectivity a BB user has on the device. As a result the code to detect a usable transport is complicated (even despite RIM has some sample code on how to do this).
In the apps development I've been involved in there were different approaches to this. However each app had networking settings which were implied to be populated by user.
For instance, one app asks user to select a transport type on app startup. :) This is definitelly an ideal solution for developers, but not for users (they simply may not know what the "network transport" is). If the target audience mostly consists of advanced users, then this will work good.
Another approach is to use some code to auto-detect a usable transport type, however this approach may also fail (for instance, if the code tries to cover a wide range of OS versions and device makes, then there are most likely will be some unexpected exclusions). So as a fallback scenario it is good to have some networking settings screen where user could check what transports to use (maybe just the only one) and APN settings.
It depends on the target audience. You could do a simplified view with basic options and and advanced view with every thing under the sun that is configurable with a reset button in case the user gets lost.
Is there a way to get a unique machine-specific system ID in a Flex application running in a browser, so that is can be used for example to determine if the machine is properly licensed to run the application?
I can't think of any way to do this based off the users machine or OS. The whole point of browser applications is to have them able to run anywhere, any time via a browser. To my knowledge Flash provides no information that could reasonable be converted into a unique machine ID for licensing purposes, not even the MAC address of a network card on the machine.
Personally, I think you'd be better off requiring a username/password for users to log in, and then using a session key stored in a cookie to allow the user to skip that step (e.g. a 'remember me on this computer' type of feature, such as GMail has). This has the advantage of the user being able to run the application from any PC they like.
Create a UUID inside flex
import mx.utils.UIDUtil;
var myUUID:string = UIDUtil.createUID();
I suppose if you want to get really clever you could encrypt this string with a locally known salt and generate some encrypted license key that can't be shared. You could change the salts or keys at regular intervals to enforce license expiration.
You will need to manage the key data on a backend somehow.
ILog Elixir does this, but they do it through a traditional install process. The swc files are watermarked, but when you enter your valid serial number unmarked swc files are unlocked and the source code is made available.
I don't have any details as to how they actually go about this, but it isn't directly through flex. Perhaps researching traditional software installation processes and unlocking encrypted data that way would produce the answer you are looking for.
You cannot really access machine specific information like MAC address or other ID's from a flex app. You should probably use some other technique like using ASP.NET or JSP.