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  • How to detect a gamepad button press on OSX 10.5 and higher?

    - by Steph Thirion
    How do I detect a button press on a USB gamepad on OSX 10.5 and higher? I can't wrap my head around the ridiculously complex HID Manager (even though apparently it was simplified with 10.5), and the code samples at Apple have thousands of lines of code that would take days to understand and isolate what I need, so I'd appreciate if someone posts a simple, and fully coded solution for this isolated problem. EDIT: so far all answers are links to source code or semi obscure libraries for all kinds of HID devices, which will require more research time than what I'd like to invest on this. I am starting a bounty to get an actual snippet of code that solves this simple problem (using an external library or not). EDIT POS BOUNTY: thanks to all for you help; but unfortunately the answer that has been automatically selected by the system is not working for me, can't figure out why; and the author has not yet replied to my comments. Any insight would be appreciated, but until a fix is found, anyone looking for resources on this topic should take this answer with a pinch of salt.

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  • Is Accessing USB from web application for cross browser cross os possible at all ?

    - by Ved
    Hey Guys, I am wondering if there is anyway we can achieve this. I heard different things about Silverlight 4 , Java Script or Active X control but not seen any demo of code for any of them. Does anyone know any web component that is available or how to write one. We really like capture client's USB drive via Web and read/write data on it. This has to work for ANY Operating system in Any web browser. Thanks UPDATED What about WPF in browser mode...I read that I can host my wpf apps inside browser and sort of like smart client. Here is a great example of doing this via silverlight 4 but author mentions about possibility of accessing USB on MAC via 1) Enable executing AppleScripts. This option will let us have the same amount of control on a mac machine as we do on a windows machine. 2) Add an overload to ComAutomationFactory.CreateObject() that calls the “Tell Application” command under the scenes and gets a AppleScript object. This option would work extremely well for Office automation. For any other operating system feature, you’ll have to code OS access twice.  I did not quite understand it. Has any tried this ?

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  • why is a minus sign prepended to my biginteger?

    - by kyrogue
    package ewa; import java.io.UnsupportedEncodingException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.logging.Level; import java.util.logging.Logger; import java.math.BigInteger; /** * * @author Lotus */ public class md5Hash { public static void main(String[] args) throws NoSuchAlgorithmException { String test = "abc"; MessageDigest md = MessageDigest.getInstance("MD5"); try { md.update(test.getBytes("UTF-8")); byte[] result = md.digest(); BigInteger bi = new BigInteger(result); String hex = bi.toString(16); System.out.println("Pringting result"); System.out.println(hex); } catch (UnsupportedEncodingException ex) { Logger.getLogger(md5Hash.class.getName()).log(Level.SEVERE, null, ex); } } } i am testing conversion of byte to hex and when done, the end result has a minus sign on the beginning of the string, why does this happen? i have read the docs and it says it will add a minus sign, however i do not understand it. And will the minus sign affect the hash result? because i am going to implement it to hash password stored on my database

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  • Where to store site settings: DB? XML? CONFIG? CLASS FILES?

    - by Emin
    I am re-building a news portal of which already have a large number of visits every day. One of the major concerns when re-building this site was to maximize performance and speed. Having said this, we have done many things from caching, to all sort of other measures to ensure speed. Now towards the end of the project, I am having a dilemma of where to store my site settings that would least affect performance. The site settings will include things such as: Domain, DefaultImgPath, Google Analytics code, default emails of editors as well as more dynamic design/display feature settings such as the background color of specific DIVs and default color for links etc.. As far as I know, I have 4 choices in storing all these info. Database: Storing general settings in the DB and caching them may be a solution however, I want to limit the access to the database for only necessary and essential functions of the project which generally are insert/update/delete news items, author articles etc.. XML: I can store these settings in an XML file but I have not done this sort of thing before so I don't know what kind of problems -if any- I might face in the future. CONFIG: I can also store these settings in web.config CLASS FILE: I can hard code all these settings in a SiteSettings class, but since the site admin himself will be able to edit these settings, It may not be the best solution. Currently, I am more close to choosing web.config but letting people fiddle with it too often is something I do not want. E.g. if somehow, I miss out a validation for something and it breaks the web.config, the whole site will go down. My concern basically is that, I cannot forsee any possible consequences of using any of the methods above (or is there any other?), I was hoping to get this question over to more experienced people out here who hopefully help make my decision.

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  • Need an Overview of Possibilities for multicolumn programming

    - by Sam
    Hi folks, From source1 and source2 i gather that IE9 will NOT support multi-column css3!! Since it is still the most popular browser (another thing i cannot understand), i am left but no other choice than to use Programming Power to make multi-columns work. Now, I use three divs that float to left, and which are manually filled with text. Please don't laugh i know its stupid! But I would wish to not to have to worry about the columns and just have a one piece of (un-interrupted) text which all goes into only 1 div, and then have a program smart enough to split it up into X equally wide columns. Question: before i start reinvent the wheel, what methods of programming power have you known that tackle this elegantly? Please suggest your best working multi-column layout sources so I can evaluate which option is the best (I will update the below table). Exploring all possibilities 2011 and further, to enable multi column text user experience: Language Author SourceCodeUsage WorksOnAllMajorBrowser? ================================================================================= html manual labour put text manually in separate left-floating divs "Y" // Upside: control! Downside: few changes necessitates to reflow 3 divs manually! CSS3 w3c css3.info/preview/multi-column-layout/ "N" // {-moz-column-count: 3; -webkit-column-count: 3; } Thats all! javascript a list apart will add url soon ? // php ? ? ? //

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  • jQuery and Ajax

    - by Banderdash
    Can anyone help with a jQuery snippet that would use Ajax to pull an XML file in on page load? Have really clunky way of doing it without jQuery here: <script type="text/javascript"> function loadXMLDoc() { if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest(); } else {// code for IE6, IE5 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { xmlDoc=xmlhttp.responseXML; var txt=""; x=xmlDoc.getElementsByTagName("title"); for (i=0;i<x.length;i++) { txt=txt + x[i].childNodes[0].nodeValue + "<br />"; } document.getElementById("checkedIn").innerHTML=txt; } } xmlhttp.open("GET","ajax-response-data.xml",true); xmlhttp.send(); } </script> Ideally rather the having a click generate the list it would do so on page load, showing the fields from the XML (title, author, and whether it is checked in or not i.e. <book id="#" checked-in="0">) Would hug you for a solution.

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  • Grails - Removing an item from a hasMany association List on data bind?

    - by ecrane
    Grails offers the ability to automatically create and bind domain objects to a hasMany List, as described in the grails user guide. So, for example, if my domain object "Author" has a List of many "Book" objects, I could create and bind these using the following markup (from the user guide): <g:textField name="books[0].title" value="the Stand" /> <g:textField name="books[1].title" value="the Shining" /> <g:textField name="books[2].title" value="Red Madder" /> In this case, if any of the books specified don't already exist, Grails will create them and set their titles appropriately. If there are already books in the specified indices, their titles will be updated and they will be saved. My question is: is there some easy way to tell Grails to remove one of those books from the 'books' association on data bind? The most obvious way to do this would be to omit the form element that corresponds to the domain instance you want to delete; unfortunately, this does not work, as per the user guide: Then Grails will automatically create a new instance for you at the defined position. If you "skipped" a few elements in the middle ... Then Grails will automatically create instances in between. I realize that a specific solution could be engineered as part of a command object, or as part of a particular controller- however, the need for this functionality appears repeatedly throughout my application, across multiple domain objects and for associations of many different types of objects. A general solution, therefore, would be ideal. Does anyone know if there is something like this included in Grails?

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  • getElementByTagName does not return comment nodes in javascript

    - by Sourabh
    Hi , I want to retrieve all the nodes present in particular DIV element.see the below test page (firefox) <HTML> <HEAD> <TITLE> New Document </TITLE> <META NAME="Generator" CONTENT="EditPlus"> <META NAME="Author" CONTENT=""> <META NAME="Keywords" CONTENT=""> <META NAME="Description" CONTENT=""> <script> function processTags() { var chNodes = document.getElementById('foo').getElementsByTagName('*') ; console.log(chNodes); } </script> </HEAD> <BODY onload="processTags();"> <div id="foo"> <!-- this is a comment -->this is some text ? <span>this is inside span</span> <div><p>test</p>test<div> </div> </BODY> </HTML> But it does not give me comments tag.. what is the best way to retrieve all tags ??

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  • How can I lookup data about a book from its barcode number?

    - by Joel Spolsky
    I'm building the world's simplest library application. All I want to be able to do is scan in a book's UPC (barcode) using a typical scanner (which just types the numbers of the barcode into a field) and then use it to look up data about the book... at a minimum, title, author, year published, and either the Dewey Decimal or Library of Congress catalog number. The goal is to print out a tiny sticker ("spine label") with the card catalog number that I can stick on the spine of the book, and then I can sort the books by card catalog number on the shelves in our company library. That way books on similar subjects will tend to be near each other, for example, if you know you're looking for a book about accounting, all you have to do is find SOME book about accounting and you'll see the other half dozen that we have right next to it which makes it convenient to browse the library. There seem to be lots of web APIs to do this, including Amazon and the Library of Congress. But those are all extremely confusing to me. What I really just want is a single higher level function that takes a UPC barcode number and returns some basic data about the book.

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  • WPF or Silverlight Learning Resources for Business Applications

    - by Refracted Paladin
    I am the only developer at a non-profit organization(~200 employees) where we are a M$ shop and 90% of the things I develop are specific to our company and are internal only. I am given a lot of latitude on how I accomplish my goals so using new technologies is in my best interest. So far I have developed all winform & asp.net applications. I would now like to focus on XAML driven development(WPF & Silverlight) and would like your help. I am subscribed to numerous Silverlight blogs and I have went through a few good tutorials however, I would really appreciate a GOOD SOLID book in my hands going forward. I prefer learning books versus reference books and I REALLY would like one from a Business standpoint as well. Shameless, self-promoting is welcomed if you happen to be an author or reviewer for one that meets my criteria. I would, however, prefer that recomendations were based on first-hand experience(no, 'my friend as this awesome book he told me about', please). Though, I don't mind un-released books if say they are an updated version of an existing. disclaimer -- I know there are an insane amount of Book posts here(SO) but none I believe for my specific need. If there is and I missed it I apologize.

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  • Lock-Free Data Structures in C++ Compare and Swap Routine

    - by slf
    In this paper: Lock-Free Data Structures (pdf) the following "Compare and Swap" fundamental is shown: template <class T> bool CAS(T* addr, T exp, T val) { if (*addr == exp) { *addr = val; return true; } return false; } And then says The entire procedure is atomic But how is that so? Is it not possible that some other actor could change the value of addr between the if and the assignment? In which case, assuming all code is using this CAS fundamental, it would be found the next time something "expected" it to be a certain way, and it wasn't. However, that doesn't change the fact that it could happen, in which case, is it still atomic? What about the other actor returning true, even when it's changes were overwritten by this actor? If that can't possibly happen, then why? I want to believe the author, so what am I missing here? I am thinking it must be obvious. My apologies in advance if this seems trivial.

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  • Is this the intention behavior in JComboBox? How I can avoid this behavior?

    - by Yan Cheng CHEOK
    I realize that if you are having a same selection in JComboBox, using up/down arrow key, will not help you to navigate the selection around. How I can avoid this behavior? See the below screen shoot /* * To change this template, choose Tools | Templates * and open the template in the editor. */ /* * NewJFrame.java * * Created on May 8, 2010, 7:46:28 PM */ package javaapplication26; /** * * @author yccheok */ public class NewJFrame extends javax.swing.JFrame { /** Creates new form NewJFrame */ public NewJFrame() { initComponents(); /* If you are having 3 same strings here. Using, up/down arrow key, * will not move the selection around. */ this.jComboBox1.addItem("Intel"); this.jComboBox1.addItem("Intel"); this.jComboBox1.addItem("Intel"); } /** This method is called from within the constructor to * initialize the form. * WARNING: Do NOT modify this code. The content of this method is * always regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { jComboBox1 = new javax.swing.JComboBox(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jComboBox1.setEditable(true); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(105, 105, 105) .addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, 158, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(137, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(63, 63, 63) .addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(217, Short.MAX_VALUE)) ); pack(); }// </editor-fold> /** * @param args the command line arguments */ public static void main(String args[]) { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new NewJFrame().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JComboBox jComboBox1; // End of variables declaration }

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  • Using CookieJar in Python to log in to a website from "Google App Engine". What's wrong here?

    - by brilliant
    Hello everybody, I've been trying to find a python code that would log in to my mail box on yahoo.com from "Google App Engine" . Here (click here to see that page) I was given this code: import urllib, urllib2, cookielib url = "https://login.yahoo.com/config/login?" form_data = {'login' : 'my-login-here', 'passwd' : 'my-password-here'} jar = cookielib.CookieJar() opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(jar)) form_data = urllib.urlencode(form_data) # data returned from this pages contains redirection resp = opener.open(url, form_data) # yahoo redirects to http://my.yahoo.com, so lets go there instead resp = opener.open('http://mail.yahoo.com') print resp.read() The author of this script looked into HTML script of yahoo log-in form and came up with this script. That log-in form contains two fields, one for users' Yahoo! ID and another one is for users' password. Here is how HTML code of that page for both of those fields looks like: User ID field: <input type="text" maxlength="96" class="yreg_ipt" size="17" value="" id="username" name="login"> Password field: <input type="password" maxlength="64" class="yreg_ipt" size="17" value="" id="passwd" name="passwd"> However, when I uploaded this code to Google App Engine I discovered that this log-in form keeps coming back to me, which, I assume, means that logging-in process didn't succeed. Why is it so?

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  • Using CookieJar in Python to log in to a website from "Google App Engine". What's wrong here?

    - by brilliant
    Hello everybody, I've been trying to find a python code that would log in to my mail box on yahoo.com from "Google App Engine" . Here (click here to see that page) I was given this code: import urllib, urllib2, cookielib url = "https://login.yahoo.com/config/login?" form_data = {'login' : 'my-login-here', 'passwd' : 'my-password-here'} jar = cookielib.CookieJar() opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(jar)) form_data = urllib.urlencode(form_data) # data returned from this pages contains redirection resp = opener.open(url, form_data) # yahoo redirects to http://my.yahoo.com, so lets go there instead resp = opener.open('http://mail.yahoo.com') print resp.read() The author of this script looked into HTML script of yahoo log-in form and came up with this script. That log-in form contains two fields, one for users' Yahoo! ID and another one is for users' password. Here is how HTML code of that page for both of those fields looks like: User ID field: <input type="text" maxlength="96" class="yreg_ipt" size="17" value="" id="username" name="login"> Password field: <input type="password" maxlength="64" class="yreg_ipt" size="17" value="" id="passwd" name="passwd"> However, when I uploaded this code to Google App Engine I discovered that this log-in form keeps coming back to me, which, I assume, means that logging-in process didn't succeed. Why is it so?

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  • Is there a definitive reference document for Ruby syntax?

    - by JSW
    I'm searching for a definitive document on Ruby syntax. I know about the definitive documents for the core API and standard library, but what about the syntax itself? For instance, such a document should cover: reserved words, string literals syntax, naming rules for variables/classes/modules, all the conditional statements and their permutations, and so forth. I know there are many books and tutorials, yes, but every one of them is essentially a tutorial, each one having a range of different depth and focus. They will all, by necessity of brevity and narrative flow, omit certain details of the language that the author deems insignificant. For instance, did you know that you can use a case statement without an initial case value, and it will then execute the first true when clause? Any given Ruby book or tutorial may or may not cover that particular lesser-known functionality of the case syntax. It's not discussed in the section in "Programming Ruby" about case statements. But that is just one small example. So far the best documentation I've found is the rubyspec project, which appears to be an attempt to write a complete test suite for the language. That's not bad, but it's a bit hard to use from a practical standpoint as a developer working on my own projects. Am I just missing something or is there really no definitive readable document defining the whole of Ruby syntax?

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  • Database schema for a library

    - by ABach
    Hi all - I'm designing a library management system for a department at my university and I wanted to enlist your eyes on my proposed schema. This post is primarily concerned with how we store multiple copies of each book; something about what I've designed rubs me the wrong way, and I'm hoping you all can point out better ways to tackle things. For dealing with users checking out books, I've devised three tables: book, customer, and book_copy. The relationships between these tables are as follows: Every book has many book_copies (to avoid duplicating the book's information while storing the fact that we have multiple copies of that book). Every user has many book_copies (the other end of the relationship) The tables themselves are designed like this: ------------------------------------------------ book ------------------------------------------------ + id + title + author + isbn + etc. ------------------------------------------------ ------------------------------------------------ customer ------------------------------------------------ + id + first_name + first_name + email + address + city + state + zip + etc. ------------------------------------------------ ------------------------------------------------ book_copy ------------------------------------------------ + id + book_id (FK to book) + customer_id (FK to customer) + checked_out + due_date + etc. ------------------------------------------------ Something about this seems incorrect (or at least inefficient to me) - the perfectionist in me feels like I'm not normalizing this data correctly. What say ye? Is there a better, more effective way to design this schema? Thanks!

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  • How do I use HTML5's localStorage in a Google Chrome extension?

    - by davidkennedy85
    I am trying to develop an extension that will work with Awesome New Tab Page. I've followed the author's advice to the letter, but it doesn't seem like any of the script I add to my background page is being executed at all. Here's my background page: <script> var info = { poke: 1, width: 1, height: 1, path: "widget.html" } chrome.extension.onRequestExternal.addListener(function(request, sender, sendResponse) { if (request === "mgmiemnjjchgkmgbeljfocdjjnpjnmcg-poke") { chrome.extension.sendRequest( sender.id, { head: "mgmiemnjjchgkmgbeljfocdjjnpjnmcg-pokeback", body: info, } ); } }); function initSelectedTab() { localStorage.setItem("selectedTab", "Something"); } initSelectedTab(); </script> Here is manifest.json: { "update_url": "http://clients2.google.com/service/update2/crx", "background_page": "background.html", "name": "Test Widget", "description": "Test widget for mgmiemnjjchgkmgbeljfocdjjnpjnmcg.", "icons": { "128": "icon.png" }, "version": "0.0.1" } Here is the relevant part of widget.html: <script> var selectedTab = localStorage.getItem("selectedTab"); document.write(selectedTab); </script> Every time, the browser just displays null. The local storage isn't being set at all, which makes me think the background page is completely disconnected. Do I have something wired up incorrectly?

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  • Need opinions on LaTeX and ever upgrading

    - by yCalleecharan
    Hi, I've been using LaTeX since 2005 with the TeXLive distribution and I've been upgrading as each new TeXLive distribution comes out. In the recent years I noticed an increase in new packages, updated packages and in one instance a new package bearing a different name replacing an old one by the same package author. A LaTeX document which relies heavily on packages and which has been produced a few years back may start to get some warnings and error messages on present-day LaTeX compilation. The primary reason I switched to LaTeX is because of its reliability and robustness to create big documents easily, not to mention the adorable typographic quality. With LaTeX one doesn't have to worry about how to open a docx in an old program supporting only doc for instance. Now, when there are so much continual changes in the packages in a LaTeX distribution, I tend to wonder when will this madness end. Not that having enhanced and new features are bad in packages, but not all updated packages are backward compatible. Eventually one would like to be able to compile a LaTeX file in 10 years time that he/she is working on at present and not get any compilation warnings/error messages due to some unpredictable behavior of updated packages or due to a package that has been cast-off from a LaTeX distribution. If I understand correctly CTAN do keep a database with all packages from different versions. I would like to know how you LaTeX users handle this issue. Thanks a lot...

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  • SQL Grouping with multiple joins combining results incorrectly

    - by Matt
    Hi I'm having trouble with my query combining records when it shouldn't. I have two tables Authors and Publications, they are related by Publication ID in a many to many relationship. As each author can have many publications and each publication has many Authors. I want my query to return every publication for a set of authors and include the ID of each of the other authors that have contributed to the publication grouped into one field. (I am working with mySQL) I have tried to picture it graphically below Table: authors Table:publications AuthorID | PublicationID PublicationID | PublicationName 1 | 123 123 | A 1 | 456 456 | B 2 | 123 789 | C 2 | 789 3 | 123 3 | 456 I want my result set to be the following AuthorID | PublicationID | PublicationName | AllAuthors 1 | 123 | A | 1,2,3 1 | 456 | B | 1,3 2 | 123 | A | 1,2,3 2 | 789 | C | 2 3 | 123 | A | 1,2,3 3 | 456 | B | 1,3 This is my query Select Author1.AuthorID, Publications.PublicationID, Publications.PubName, GROUP_CONCAT(TRIM(Author2.AuthorID)ORDER BY Author2.AuthorID ASC)AS 'AuthorsAll' FROM Authors AS Author1 LEFT JOIN Authors AS Author2 ON Author1.PublicationID = Author2.PublicationID INNER JOIN Publications ON Author1.PublicationID = Publications.PublicationID WHERE Author1.AuthorID ="1" OR Author1.AuthorID ="2" OR Author1.AuthorID ="3" GROUP BY Author2.PublicationID But it returns the following instead AuthorID | PublicationID | PublicationName | AllAuthors 1 | 123 | A | 1,1,1,2,2,2,3,3,3 1 | 456 | B | 1,1,3,3 2 | 789 | C | 2 It does deliver the desired output when there is only one AuhorID in the where statement. I have not been able to figure it out, does anyone know where i'm going wrong?

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  • JSDoc with AngularJS

    - by Nick White
    Currently within my Project we are using JSDoc, we have recently started to implement Angular and I want to continue using JSDoc to ensure that all the documentation is within the same place. I have taken a look at people mainly just saying to use ngDoc but this isn't really a viable option as we will always have separate JavaScript and I ideally would have everything together. /** * @author Example <[email protected]> * @copyright 2014 Example Ltd. All rights reserved. */ (function () { window.example = window.example || {}; /** * Example Namespace * @memberOf example * @namespace example.angular */ window.example.angular = window.example.angular || {}; var exAngular = window.example.angular; /** * A Example Angular Bootstrap Module * @module exampleAngularBootstrap */ exAngular.bootstrap = angular.module('exampleAngularBootstrap', [ 'ngRoute', 'ngResource', 'ngCookies' ]) .run(function ($http, $cookies) { $http.defaults.headers.post['X-CSRFToken'] = $cookies.csrftoken; $http.defaults.headers.common['X-CSRFToken'] = $cookies.csrftoken; }); })(); Currently this is what I have but am unable to put documentation for the run() any ideas? Thank you in advanced!

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  • Async task ASP.net HttpContext.Current.Items is empty - How do handle this?

    - by GuruC
    We are running a very large web application in asp.net MVC .NET 4.0. Recently we had an audit done and the performance team says that there were a lot of null reference exceptions. So I started investigating it from the dumps and event viewer. My understanding was as follows: We are using Asyn Tasks in our controllers. We rely on HttpContext.Current.Items hashtable to store a lot of Application level values. Task<Articles>.Factory.StartNew(() => { System.Web.HttpContext.Current = ControllerContext.HttpContext.ApplicationInstance.Context; var service = new ArticlesService(page); return service.GetArticles(); }).ContinueWith(t => SetResult(t, "articles")); So we are copying the context object onto the new thread that is spawned from Task factory. This context.Items is used again in the thread wherever necessary. Say for ex: public class SomeClass { internal static int StreamID { get { if (HttpContext.Current != null) { return (int)HttpContext.Current.Items["StreamID"]; } else { return DEFAULT_STREAM_ID; } } } This runs fine as long as number of parallel requests are optimal. My questions are as follows: 1. When the load is more and there are too many parallel requests, I notice that HttpContext.Current.Items is empty. I am not able to figure out a reason for this and this causes all the null reference exceptions. 2. How do we make sure it is not null ? Any workaround if present ? NOTE: I read through in StackOverflow and people have questions like HttpContext.Current is null - but in my case it is not null and its empty. I was reading one more article where the author says that sometimes request object is terminated and it may cause problems since dispose is already called on objects. I am doing a copy of Context object - its just a shallow copy and not a deep copy.

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  • Importing external .jar file to Android project

    - by robintw
    I've read various answers to similar questions on StackOverflow, so I apologise if I'm repeating another question, but I can't seem to get this to work. I have a standard java project in which I've written code to parse some BBC Radio XML data from the internet. The project is called BBCSchedules and the class I'm interested in is called BBCChannel. I'm now trying to use the BBCChannel class in an android application. How should I go about doing this? I've tried various things, following various bits of advice on the internet, and the place I've got to at the moment is compiling my BBCSchedules project to a .jar file, and importing that to the Android project using the Build Path/Library/Add External Jar option. However, Eclispe still doesn't recognise the BBCChannel class, and won't let me run the application because of this. I guess I've done something silly wrong, but what is it? Cheers, Robin UPDATE: I've tried the steps listed in http://stackoverflow.com/questions/1334802/how-can-i-use-external-jars-in-an-android-project and various other StackOverflow questions I can find that seem to be related to this, but absolutely nothing seems to work. Any other ideas? UPDATE: The discussions I've had with the author of the first answer below suggest that it is something to do with how I am using Eclipse to attach the .jar file. The project he sent me with the .jar file already attached didn't work. Any other ideas anyone?

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  • What Are The Ways to Devide Text in Multi-Column? Need an Overview of Possibilities.

    - by Sam
    Hi folks, From source1 and source2 i gather that IE9 will NOT support multi-column css3!! Since it is still the most popular browser (another thing i cannot understand), i am left but no other choice than to use Programming Power to make multi-columns work. Now, I use three divs that float to left, and which are manually filled with text. Please don't laugh i know its stupid! But I would wish to not to have to worry about the columns and just have a one piece of (un-interrupted) text which all goes into only 1 div, and then have a program smart enough to split it up into X equally wide columns. Question: before i start reinvent the wheel, what methods of programming power have you known that tackle this elegantly? Please suggest your best working multi-column layout sources so I can evaluate which option is the best (I will update the below table). Exploring all possibilities 2011 and further, to enable multi column text user experience: Language Author SourceCodeUsage WorksOnAllMajorBrowser? ================================================================================= html manual labour put text manually in separate left-floating divs "Y" // Upside: control! Downside: few changes necessitates to reflow 3 divs manually! CSS3 w3c css3.info/preview/multi-column-layout/ "N" // {-moz-column-count: 3; -webkit-column-count: 3; } Thats all! javascript a list apart will add url soon ? // php ? ? ? //

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  • XP Leveling System - PHP

    - by Michael Rich
    Rank Table ID, Primary Key RANK, The rank or level, 1 being the highest and 3 the lowest MIN_SCORE, The minimum amount of point or XP needed to reach the rank NAME, The associated name of the rank Rank Table +----+------+-----------+-------------------------+ | ID | RANK | MIN_SCORE | NAME | +----+------+-----------+-------------------------+ | 1 | 1 | 18932 | Editor-in-Chief | | 2 | 2 | 15146 | Senior Technical Writer | | 3 | 3 | 12116 | Senior Copywriter | +----+------+-----------+-------------------------+ Ranking Table ID, Primary Key FK_MEMEBER_ID, Foreign Key to member's Primary Key FK_RANK, Foreign Key to Author Rank Table's Rank column (top) SCORE, The member's current earned score or XP Ranking Table +-----+--------------+---------+-------+ | ID | FK_MEMBER_ID | FK_RANK | SCORE | +-----+--------------+---------+-------+ | 1 | 1 | 1 | 17722 | | 2 | 2 | 2 | 16257 | | 3 | 3 | 3 | 12234 | +-----+--------------+---------+-------+ In my class I have stored the ranks -- matching those in the Rank Table -- and correlating minimum scores; RANK as key and MINIMUM_SCORE as value. When a member's score (XP) is updated (up/down) I want to test that updated score against the below array to determine if their rank needs updating too. private $scores = array('3' => '12116', '2' => '15146', '1' => '18932',); Using the updated score, how could I determine the correlating rank from the above array? Everything is open to scrutiny, this is my first time creating a ranking system so I hope to get it right :)

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  • C++ design question, container of instances and pointers

    - by Tom
    Hi all, Im wondering something. I have class Polygon, which composes a vector of Line (another class here) class Polygon { std::vector<Line> lines; public: const_iterator begin() const; const_iterator end() const; } On the other hand, I have a function, that calculates a vector of pointers to lines, and based on those lines, should return a pointer to a Polygon. Polygon* foo(Polygon& p){ std::vector<Line> lines = bar (p.begin(),p.end()); return new Polygon(lines); } Here's the question: I can always add a Polygon (vector Is there a better way that dereferencing each element of the vector and assigning it to the existing vector container? //for line in vector<Line*> v //vcopy is an instance of vector<Line> vcopy.push_back(*(v.at(i)) I think not, but I dont really like that approach. Hopefully, I will be able to convince the author of the class to change it, but I cant base my coding right now to that fact (and i'm scared of a performance hit). Thanks in advance.

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