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  • Exposing a C++ API to C#

    - by Siyfion
    So what I have is a C++ API contained within a *.dll and I want to use a C# application to call methods within the API. So far I have created a C++ / CLR project that includes the native C++ API and managed to create a "bridge" class that looks a bit like the following: ManagedBridge.h namespace ManagedAPIWrapper { public ref class Bridge { public: int bridge_test(void); int bridge_test2(api_struct* temp); } } ManagedBridge.cpp int Bridge::bridge_test(void) { return test(); } int Bridge::bridge_test2(api_struct* temp) { return test2(temp); } I also have a C# application that has a reference to the C++/CLR "Bridge.dll" and then uses the methods contained within. I have a number of problems with this: I can't figure out how to call bridge_test2 within the C# program, as it has no knowledge of what a api_struct actually is. I know that I need to marshal the object somewhere, but do I do it in the C# program or the C++/CLR bridge? This seems like a very long-winded way of exposing all of the methods in the API, is there not an easier way that I'm missing out? (That doesn't use P/Invoke!)

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  • Return value of a JQuery autocomplete using an array of objects as its source

    - by user2920430
    In a JQuery autocomplete which uses an array of objects as its source, can I display the label in the INPUT and later access the value? The default behavior is that the value is displayed in the INPUT after selection. In this case the values represent indexes to unique keys in rows in a table. <!doctype html> <html lang="en"> <head> <meta charset="utf-8"> <title>autocomplete demo</title> <link rel="stylesheet" href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css"> <script src="http://code.jquery.com/jquery-1.9.1.js"></script> <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script> </head> <body> <label for="autocomplete">Select a programming language: </label> <input id="autocomplete"> <script> $( "#autocomplete" ).autocomplete({ source: [ { label:"c++", value:1 }, { label: "java", value:2 }, { label: "javascript", value:3 } ] }); </script> </body> </html>

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  • Sockets and COBOL

    - by kati
    I have received a job at a hospital which still uses COBOL for all organizational work, the whole (now 20 Terabyte) database (Which was a homebrew in, guess what, COBOL) is filled with the data of every patient since the last 45 (or so) years. So that was my story. Now to my question: Currently, all sockets were (from what I've seen) implemented by COBOL programs writing their data into files. These files then were read out by C++ programs (That was an additional module added in the late 1980s) and using C++ sockets sent to the database. Now this solution has stopped working as they are moving the database from COBOL to COBOL, yes - they didn't use MySQL or so - they implemented a new database - again in COBOL. I asked the guy that worked there before me (hes around 70 now) why the hell someone would do that and he told me that he is so good at COBOL that he doesn't want to write it in any other language. So far so good now my question: How can I implement socket connections in COBOL? I need to create an interface to the external COBOL database located at, for example, 192.168.1.23:283.

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  • Replacing mysql user authentication with openid

    - by David
    So, I'm working with a really old system which uses a person's mysql database credentials to authenticate to a web site (the database was originally only accessed from the command line, but is now accessed from a php frontend). Because of some internal reasons (and to preserve the user's history), I have to leave the old authentication intact. I've been charged with adding openid authentication to this system. Somehow I need to be able to retrieve a users mysql username and password upon logging into the site through openid (using the Zend framework, by the way). I've thought of simply requiring registration at the first login, where the user must provide their mysql credentials, but I'd rather not store the password plain text. I've also considered blanking everyone's mysql passwords, and just setting the user's mysql username manually (rather than having the user provide this, since they could provide any username). This is turning into a security nightmare. Does anyone have any suggestions for alternatives? This is running on a Linux server, by the way. Also, I can't use mysql pluggable authentication because the mysql version is 5.0 (pluggable authentication requires mysql 5.5), and no, I can't update it.

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  • CSS to Make 2 Column Content Areas

    - by Joe Majewski
    I'm trying to stray away from using tables to form the layout of my content, and I can think of two alternatives that I'd like to better learn: (1) styling list items to be side-by-side, and (2) using div blocks that float onto the same line. Both of these would have their own uses for what I'm working on. I'm already using div tags to form the entire layout of my three-column template, but what I need to do now is a bit different. In case it helps, my project can be found here. In short, here's my question; how would I style a div so that the width of it is 50% of the width of the area it occupies, rather than 50% of the width of the page? As for my other question, what would be the best approach to styling list items so that they are side-by-side? I'm working on a registration script now, and instead of using a table with "Username" on the left and the input text on the right, I can use two list items. It's late and I've been working on this project of mine for about 8 hours straight now, so I apologize if I'm asking anything confusing. Feel free to ask me any questions about what I'm trying to do. Thanks, friends. :)

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  • Pass 2-dimensional array trough view

    - by Mikael
    Hi, I'm trying to print a 2-dimensional array but can't figure it out. My controller uses this code: public ActionResult Test(string str) { DateTimeOffset offset = new DateTimeOffset(DateTime.Now); offset = offset.AddHours(-5); string[,] weekDays = new string[7,2]; for (int i = 0; i < 7; i++) { weekDays[i,0] = String.Format("{0:yyyy-MM-dd:dddd}", offset); //Date weekDays[i,1] = String.Format("{0:dddd}", offset); //Text offset = offset.AddHours(24); } weekDays[0,1] = "Today"; ViewData["weekDays"] = weekDays; return View(); } Now I wan't to print this array of weekdays as a dropdown-list and i thought this would work: <% foreach (var item in (string[,])ViewData["weekDays"]) { %> <option value=" <%= item[0] %> "> <%= item[1] %> </option> <% } %> But that's not the case, this code output just the first char of the string. So anyone got a suggestion? Thanks! /M

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  • Is there a way to rotate an html table?

    - by Josh
    Is there a way to rotate an html table? So, say I had a table like this: <table id="table-1" cellspacing="0" cellpadding="2"> <tr><td>1</td></tr> <tr><td>2</td></tr> <tr><td>3</td></tr> <tr><td>4</td></tr> <tr><td>5</td></tr> <tr><td>6</td></tr> </table> and wanted to some sort of button that had javascript behind it that could rotate the table any which direction. For example, clicking the right button, results in: <table id="table-1" cellspacing="0" cellpadding="2"> <tr><td>6</td><td>5</td><td>4</td><td>3</td><td>2</td><td>1</td></tr> </table> I have a drag and drop plugin that uses a table, and I am trying to do a piece that allows for a user to add to a queue (that results in the table), and then they can also rotate it around as well. Thanks.

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  • OCR combined with font recognition?

    - by Adam
    I have a bold idea where a user could take an image like the following and in a few seconds of processing, be able to edit a document which looks roughly the same. The software would use WhatTheFont (or something similar) to recognize the fonts used, and OCR and other software to handle the font size, color, line-spacing, and of course the text content itself. In the case of the example image, there would be three separate "textboxes" produced, each starting at the upper left corner of the text, and extending as far to the bottom right as it could before running into another text box. So the user would then see something like this: (The rectangles are just used to show the boundaries of each textbox.) From here, the user would be able to edit the text in each of these boxes to create a new document. Of course there are tons of obvious uses for such an application, especially on a mobile phone with a built in camera. So my questions are the following: I doubt the answer is yes, but does anything do this already? If I'm going to try to build this, what should I write it in? Can I use Python? What would be the best OCR libraries to start with? Is there a service other than WhatTheFont for font recognition that has better API support? Anybody want to help me build it? :) etc. etc. Update: One thing I wanted to mention (but forgot) is I would also like the background to be preserved. In other words, if the example above had an image behind the text, I'd like the document to use that image with text removed. I know this complicates things a lot because that would require some image editing techniques too (something akin to Photoshop CS5' "content-aware fill"). But if we can solve diminished reality on iPhones, I think we can figure this out!

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  • My HTML5 web app crashes and I have no clue how to debug

    - by Shouvik
    Hi All, I have written a word game using HTML5 canvas tag and a little bit of audio. I developed the application on the chrome web browser on a linux system. Recently during the testing phase it was tried on safari 5.0.3 on Mac and the webpage froze. Not just the canvas element, but interactive element on the page froze. I have at some times experienced this problem on google chrome when I was developing but since the console did not throw any error before this happened, I did not give it much credence. Now as per requirements I am supposed to support both chrome and safari but this dismal performance on safari has left me shocked and I cannot see what error can be thrown which might lead to such a situation. Worse yet the CPU usage on using this application peaks to 70-80percent on my 2yr old macbook running ubuntu... I can only but pity the person who uses mac to operate this app, which undoubtedly is a heavier OS. Could someone help me out with a place I can start with to find out what exactly is causing this issue. I have run profiles on this webapp on google chromes console and noticed that in the heap spanshot value increases steadily with the playing of the game, specifically (root) value which jumps up by 900 counts. Any help would be very appreciated! Thanks EDIT: I don't know if this helps, but I have noticed that even on refreshing the page after the app becomes unresponsive the page reloads and I am still not able to interact with the page elements but the tab scroll bar continues to work and I can see my application window completely. So to summaries the tab stops accepting any sort of user interaction inside the page. Edit2: Nop. It doesn't work still... The app crashes on double click on the canvas element. The console is not throwing any errors either! =/ I have noticed this problem is isolated only to safari!

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  • jQuery not working as expected on HTTPS Internet explorer

    - by jat
    When I try to run my code on any other webbrowsers apart from the Internet explorer it works fine. But when I try to run the code on Internet explorer I do get an alert box saying HERE along with an Ok button. but the problem is when I click on that OK button I do not get anything. Ideally I should be getting another alert box. <!DOCTYPE html> <html> <head> <script src="js/jquery-1.4.2.min.js"></script> <script type="text/javascript"> $(document).ready(function(){ $("#submit").click(function(event) { alert("here"); $.post('process.php', {name:'test1',email:'test.com'}, function(data) { $('#results').html(data); alert(data); }); }); }); </script> </head> <body> <form name="myform" id="myform" action="" method="POST"> <label for="name" id="name_label">Name</label> <input type="text" name="name" id="name" size="30" value=""/> <br> <label for="email" id="email_label">Email</label> <input type="text" name="email" id="email" size="30" value=""/> <br> <input type="button" name="submit" id="submit" value="Submit"> </form> <div id="results"><div> </body> </html> Any help on this is very much appreciated. Edit: I found out that Internet Explorer which has HTTP works perfectly fine but not on Internet Explorer which uses HTTPS.

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  • Integration testing - can it be done right?

    - by Max
    I used TDD as a development style on some projects in the past two years, but I always get stuck on the same point: how can I test the integration of the various parts of my program? What I am currently doing is writing a testcase per class (this is my rule of thumb: a "unit" is a class, and each class has one or more testcases). I try to resolve dependencies by using mocks and stubs and this works really well as each class can be tested independently. After some coding, all important classes are tested. I then "wire" them together using an IoC container. And here I am stuck: How to test if the wiring was successfull and the objects interact the way I want? An example: Think of a web application. There is a controller class which takes an array of ids, uses a repository to fetch the records based on these ids and then iterates over the records and writes them as a string to an outfile. To make it simple, there would be three classes: Controller, Repository, OutfileWriter. Each of them is tested in isolation. What I would do in order to test the "real" application: making the http request (either manually or automated) with some ids from the database and then look in the filesystem if the file was written. Of course this process could be automated, but still: doesn´t that duplicate the test-logic? Is this what is called an "integration test"? In a book i recently read about Unit Testing it seemed to me that integration testing was more of an anti-pattern?

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  • [Rails] Accessing error_messages on form_tag

    - by aaronrussell
    I have built a custom form for creating a joining model on a has_many :through relationship. The models look roughly like this: class Team has_many :team_members has_many :members, :through => :team_members end class Member has_many :team_members has_many :teams, :through => :team_members end class TeamMember belongs_to :team belongs_to :member # and this model has some validations too end The form I have built is for selecting which members should be in a team. I won't paste the form, but it uses the form_tag method and basically sends an array of hashes which contain a member_id and a squad_number. I then update the database with an action that looks roughly like this (simplified a bit, but you get the jist): @team.transaction do @team.team_members = params[:team_members].collect{|tm| @team.team_members.new(tm)} if @team.save redirect_to ... else render :action => :members end end Everything works great but I am validating the squad_number for uniqueness and numerically. So, when any of those validations fail, how do I get access to them in my view, and how do I ascertain which of the many members it has failed on?

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  • Is Using Tuples in my .NET 4.0 Code a Poor Design Decision?

    - by Jason Webb
    With the addition of the Tuple class in .net 4, I have been trying to decide if using them in my design is a bad choice or not. The way I see it, a Tuple can be a shortcut to writing a result class (I am sure there are other uses too). So this: public class ResultType { public string StringValue { get; set; } public int IntValue { get; set; } } public ResultType GetAClassedValue() { //..Do Some Stuff ResultType result = new ResultType { StringValue = "A String", IntValue = 2 }; return result; } Is equivalent to this: public Tuple<string, int> GetATupledValue() { //...Do Some stuff Tuple<string, int> result = new Tuple<string, int>("A String", 2); return result; } So setting aside the possibility that I am missing the point of Tuples, is the example with a Tuple a bad design choice? To me it seems like less clutter, but not as self documenting and clean. Meaning that with the type ResultType, it is very clear later on what each part of the class means but you have extra code to maintain. With the Tuple<string, int> you will need to look up and figure out what each Item represents, but you write and maintain less code. Any experience you have had with this choice would be greatly appreciated.

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  • Timestamps and Intervals: NUMTOYMINTERVAL SYSTDATE CALCULATION SQL QUERY

    - by MeachamRob
    I am working on a homework problem, I'm close but need some help with a data conversion I think. Or sysdate - start_date calculation The question is: Using the EX schema, write a SELECT statement that retrieves the date_id and start_date from the Date_Sample table (format below), followed by a column named Years_and_Months_Since_Start that uses an interval function to retrieve the number of years and months that have elapsed between the start_date and the sysdate. (Your values will vary based on the date you do this lab.) Display only the records with start dates having the month and day equal to Feb 28 (of any year). DATE_ID START_DATE YEARS_AND_MONTHS_SINCE_START 2 Sunday , February 28, 1999 13-8 4 Monday , February 28, 2005 7-8 5 Tuesday , February 28, 2006 6-8 Our EX schema that refers to this question is simply a Date_Sample Table with two columns: DATE_ID NUMBER NOT Null START_DATE DATE I Have written this code: SELECT date_id, TO_CHAR(start_date, 'Day, MONTH DD, YYYY') AS start_date , NUMTOYMINTERVAL((SYSDATE - start_date), 'YEAR') AS years_and_months_since_start FROM date_sample WHERE TO_CHAR(start_date, 'MM/DD') = '02/28'; But my Years and months since start column is not working properly. It's getting very high numbers for years and months when the date calculated is from 1999-ish. ie, it should be 13-8 and I'm getting 5027-2 so I know it's not correct. I used NUMTOYMINTERVAL, which should be correct, but don't think the sysdate-start_date is working. Data Type for start_date is simply date. I tried ROUND but maybe need some help to get it right. Something is wrong with my calculation and trying to figure out how to get the correct interval there. Not sure if I have provided enough information to everyone but I will let you know if I figure it out before you do. It's a question from Murach's Oracle and SQL/PL book, chapter 17 if anyone else is trying to learn that chapter. Page 559.

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  • Combine MD5 hashes of multiple files

    - by user685869
    I have 7 files that I'm generating MD5 hashes for. The hashes are used to ensure that a remote copy of the data store is identical to the local copy. Unfortunately, the link between these two copies of the data is mind numbingly slow. Changes to the data are very rare but I have a requirement that the data be synchronized at all times (or as soon as possible). Rather than passing 7 different MD5 hashes across my (extremely slow) communications link, I'd like to generate the hash for each file and then combine these hashes into a single hash which I can then transfer and then re-calculate/use for comparison on the remote side. If the "combined hash" differs, then I'd start sending the 7 individual hashes to determine exactly which file(s) have been changed. For example, here are the MD5 hashes for the 7 files as of last week: 0709d609d69385255c496436eb50402c 709465a74411bd596595c7b9b158ae6a 4ab657320ef33e3d5eb498e4c13d41b7 3b49c6ab199994fd776bb63761414e72 0fc28c5a010fc3c06c0c930c88e31a15 c4ecd214662cac5aae0e53f6f252bf0e 8b086431e43148a2c2d943ba30d31cc6 I'd like to combine these hashes together such that I get a single unique value (perhaps another MD5 hash?) that I can then send to the remote system. On the remote system, I'd then perform the same calculation to determine if the data as a whole has been changed. If it has, then I'd start sending the individual hashes, etc. The most important factor is that my "combined hash" be short enough so that it uses less bandwidth than just sending all 7 hashes in the first place. I thought of writing the 7 MD5 hashes to a file and then hashing that file but is there a better way?

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  • Is there a Form.Invoke() method?

    - by rubicon
    Hi, I am new to multithreading (and also to C#) so I hope this is not obvious: In my Form (WinForms application, .NET 2.0) I subscribed to an event that is raised by another object, and on handling this event I wish to change several Controls on my Form. As this event is raised in another thread than the main (UI) thread I want to marshal the call to the Form's thread. I understand I could use the Control.Invoke() method on any Control that I want to change, but as there are several of them I do not wish to do that. When searching the internet I found hints that the Form class itself provides an Invoke() method. See for example: http://marioschneider.blogspot.com/2008/04/invoke-methode-fr-multithread.html (Sorry, as I am I new user I can't seem to post more than one link. I will add more links as comments if possible.) With that, I could just wrap my event handler and then use it as if it was called on the UI thread. However, this doesn't seem to be defined in my environment, and in MSDN's System.Windows.Forms.Form documentation there's also no sign of it. Does this method exist in the .NET-Framework? I find it hard to believe that Form would not supply such a method, as it uses the same message queue the Controls on it do. (Or am I missing something here?)

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  • TCP/IP Implementation General Questions

    - by user2971023
    I've implemented the concepts shown here; http://wiki.unity3d.com/index.php/Simple_TCP/IP_Client_-_Server outside of unity and it works. (though i had to create the TCPIPServerApp from scratch as i could not find the base project anywhere). I have some general questions on how to use tcp/ip properly however. I've done some research on tcp/ip itself but I'm still a little confused. It seems like using the method above doesn't guarantee that I'll see the message (res). It just checks on every update to see if there is a different message in res. What if multiple messages are sent and the program lags or something, will i miss the earlier packet(s)? Should i instead do an array so it stores the last X messages? How do i know the data was received? Do I need to add a message id and build in my own ack into the data? Should i check to see if the port is in use before setting up a connection? Sorry for all the questions. This is all new to me but I enjoy this very much! ... Below already answered By Anton, Thanks It sounds like tcp uses its own packet numbering to ensure the packets end up in the right order on the other side. What if a packet is missed, are the subsequent packets thrown away? Or is this numbering and packet ordering, only for handling data that is broken out into multiple packets? TCP will automatically break the data into multiple packets if necessary right?

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  • .net remoting - Better solution to wait for a service to initialize ?

    - by CitizenInsane
    Context I have a client application (which i cannot modify, i.e. i only have the binary) that needs to run from time to time external commands that depends on a resource which is very long to initialize (about 20s). I thus decided to initialize this resource once for all in a "CommandServer.exe" application (single instance in the system tray) and let my client application call an intermediate "ExecuteCommand.exe" program that uses .net remoting to perform the operation on the server. The "ExecuteCommand.exe" is in charge for starting the server on first call and then leave it alive to speed up further commands. The service: public interface IMyService { void ExecuteCommand(string[] args); } The "CommandServer.exe" (using WindowsFormsApplicationBase for single instance management + user friendly splash screen during resource initializations): private void onStartupFirstInstance(object sender, StartupEventArgs e) { // Register communication channel channel = new TcpServerChannel("CommandServerChannel", 8234); ChannelServices.RegisterChannel(channel, false); // Register service var resource = veryLongToInitialize(); service = new MyServiceImpl(resource); RemotingServices.Marshal(service, "CommandServer"); // Create icon in system tray notifyIcon = new NotifyIcon(); ... } The intermediate "ExecuteCommand.exe": static void Main(string[] args) { startCommandServerIfRequired(); var channel = new TcpClientChannel(); ChannelServices.RegisterChannel(channel, false); var service = (IMyService)Activator.GetObject(typeof(IMyService), "tcp://localhost:8234/CommandServer"); service.RunCommand(args); } Problem As the server is very long to start (about 20s to initialize the required resources), the "ExecuteCommand.exe" fails on service.RunCommand(args) line because the server is yet not available. Question Is there a elegant way I can tune the delay before to receive "service not available" when calling service.RunCommand ? NB1: Currently I'm working around the issue by adding a mutex in server to indicate for complete initiliazation and have "ExecuteCommand.exe" to wait for this mutex before to call service.RunCommand. NB2: I have no background with .net remoting, nor WCF which is recommended replacer. (I chose .net remoting because this looked easier to set-up for this single shot issue in running external commands).

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  • How to handle exceptions from an image-generating Servlet?

    - by ssahmed555
    I have a simple (Servlet, JSP, and JSTL) web app whose main functionality is displaying images retrieved from a back-end server. The controller servlet forwards the user to a JSP that in turn uses another Servlet to display the resulting image on that same JSP. Further down, the JSP has a line similar to: <a href="<c:out value='${imageURL}'/>"><img src="<c:out value='${imageURL}'/>" alt="image view" border="1"></a> which invokes a GET request on the image-generating servlet causing it to generate the image. My question is: how do I handle Exceptions thrown by this image-generating servlet? I already have an error page defined (in web.xml) to handle ServletException within my web app but this doesn't work for this image-generating Servlet, and results in the following errors showing up in my Tomcat server logs: SEVERE: Exception Processing ErrorPage[exceptionType=javax.servlet.ServletException, location=/WEB-INF/ExceptionPage.jsp] java.lang.IllegalStateException: Cannot reset buffer after response has been committed What's my recourse in this situation? I'd like to be able to handle Exceptions thrown from this image-generating Servlet, and display some error on the main UI or forward the user to another error page.

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  • Windows Unique Identifier?

    - by user775013
    So there is this software. When installed it somehow (probably reads file or registry entry) recognizes my windows operating system. It's supposed to do some tasks only once per unique computer. If I uninstall the program and re install it, the software remembers that it has been installed and therefore do not do the task. If I use system restore, software also does not do the tasks. If I load image of the system before the install, software also doesn't do the tasks. If I re install a fresh copy of windows, then only the software does the task. IP even does not matter. Everything is the same, except it is a brand new copy of Windows operating system. So I guess that the software reads some kind of unique operating system identifier, then connects to server to create a user profile. So the question is? What could be those files which software uses to check system identifier? So far I have found out that there are entries under registry. WindowsNT/CurrentVersion and Windows/Cryptography but software do not rely on them. Where else should I search? Any software which could help me find out?

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  • Swing Menu dimensions

    - by ikurtz
    Greetings. I am trying to learn Java and Swing (today is my first day). I have been able to set up a menu in my test application. but the items occupy very little space (they are narrow). How do I go about extendng the amount of space it uses? I am studying Teach Yourself Java 6 in 21 Days 5th Ed, Java Swing, 2nd Edition, 2002 and Teach Yourself Programming With Java In 24 Hours, 4th Edition (2005) but none of them shed any light on this issue. EDIT: Menu code: JMenu _Game = new JMenu("Game"); JMenuItem _New = new JMenuItem("New"); JMenuItem _Exit = new JMenuItem("Exit"); JMenu _Turn = new JMenu("Turn"); JMenuItem _Red = new JMenuItem("Red"); JMenuItem _Yellow = new JMenuItem("Yellow"); _Turn.add(_Red); _Turn.add(_Yellow); _Game.add(_New); _Game.addSeparator(); _Game.add(_Turn); _Game.addSeparator(); _Game.add(_Exit); JMenu _Help = new JMenu("Help"); JMenuItem _About = new JMenuItem("About"); _Help.add(_About); JMenuBar _MenuBar = new JMenuBar(); _MenuBar.add(_Game); _MenuBar.add(_Help); setJMenuBar(_MenuBar); EDIT: Solved! JMenuItem _New = new JMenuItem("New "); just add spaces as needed! simple.

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  • Difference between std::result_of and decltype

    - by Luc Touraille
    I have some trouble understanding the need for std::result_of in C++0x. If I understood correctly, result_of is used to obtain the resulting type of invoking a function object with certain types of parameters. For example: template <typename F, typename Arg> typename std::result_of<F(Arg)> invoke(F f, Arg a) { return f(a); } I don't really see the difference with the following code: template <typename F, typename Arg> auto invoke(F f, Arg a) -> decltype(f(a)) //uses the f parameter { return f(a); } or template <typename F, typename Arg> auto invoke(F f, Arg a) -> decltype(F()(a)); //"constructs" an F { return f(a); } The only problem I can see with these two solutions is that we need to either: have an instance of the functor to use it in the expression passed to decltype. know a defined constructor for the functor. Am I right in thinking that the only difference between decltype and result_of is that the first one needs an expression whereas the second does not?

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  • How to properly manage a complex DB structure?

    - by errr
    Let's say you have several systems using the same DB - each uses several schemes (sometimes same as the other). This structure of these schemes is somewhat very big and complicated. Now, how could you possibly manage such scheme structure? Obviously using some sort of "configuration" - the simplest would be SQL scripts, but a more reasonable solution would be XMLs which can be easily converted into SQL, or some other readable solution (for example, JPA's XMLs or Annotations). This solution though, causes a problem where you can't really tell if your configuration matches the structure of the DB schemes exactly. You can't say if those two are synchronized. Why wouldn't they? Well, in such big structure there are going to be many changes, and you won't always remember to save/commit your configuration after you've altered the schemes, or maybe you did save/commit it, but eventually didn't altered anything in the schemes and forgot to undo the changes to the configuration. More than that, another problem (not caused by the configuration, but isn't addressed by it either) is versioning. I don't see any good way of managing the DB schemes versions (say our last alteration makes 3 systems crash - not good, how to "rollback"?). And thoughts? thx.

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  • What is the best way to embed SQL in VB.NET.

    - by Amy P
    I am looking for information on the best practices or project layout for software that uses SQL embedded inside VB.NET or C#. The software will connect to a full SQL DB. The software was written in VB6 and ported to VB.NET, we want to update it to use .NET functionality but I am not sure where to start with my research. We are using Visual Studio 2005. All database manipulations are done from VB. Update: To clarify. We are currently using SqlConnection, SqlDataAdapter, SqlDataReader to connect to the database. What I mean by embed is that the SQL stored procedures are scripted inside our VB code and then run on the db. All of our tables, stored procs, views, etc are all manipulated in the VB code. The layout of our code is quite messy. I am looking for a better architecture or pattern that we can use to organize our code. Can you recommend any books, webpages, topics that I can google, etc to help me better understand the best way for us to do this.

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  • Configuring WPA WiFi in Ubuntu 10.10

    - by sma
    Hello, I am trying to configure my wireless network on my laptop running Ubuntu 10.10 and am having a bit of difficulty. I am a complete Linux newb, but want to learn it, hence the reason I'm trying to set this up. Here's the vitals: It is a Gateway 600 YG2 laptop. It was previously running Windows XP, but I installed Ubuntu 10.10 in place of it (not a dual boot, I removed XP altogether). I have an old wireless card that I'm trying to resurrect. I haven't really used the card in a couple years, but it seems to still work, I just can't connect to my home's wireless network. The card is a Linksys WPC11 v2.5. When I plug it in, Ubuntu recognizes the network, but won't connect to it. My home network uses WPA encryption and the only connection type that Ubuntu's network manager is giving me is WEP and then it asks for a key -- I have no idea what that key should be. So, basically, I'm asking, is there a way I can instead connect through WPA? I've tried creating a new connection in network manager, but that won't work, it keeps falling back to the WEP connection and asking me for a key. I have tried to install the XP driver using ndiswrapper but I don't know if that's working or not. Is there a way to tell if: A) the card is working as it should B) the correct drivers are installed (again, I installed the XP one using ndiswrapper NET8180.INF, but I'm not sure what to do next) Any help would be appreciated. Thank you.

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