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  • Cloning a selector + all its children in jQuery?

    - by HipHop-opatamus
    I'm having trouble getting the following JQuery script to function properly - its functionality is as follows: 1) Hide the content below each headline 2) Upon clicking a headline, substitute the "#first-post" with the headline + the hidden content below the headline. I can only seem to get the script to clone the headline itself to #first-post, not the headline + the content beneath it. Any idea why? <HTML> <HEAD> <script src="http://code.jquery.com/jquery-latest.js"></script> </HEAD> <script> $(document).ready( function(){ $('.title').siblings().hide(); $('.title').click( function() { $('#first-post').replaceWith($(this).closest(".comment").clone().attr('id','first-post')); $('html, body').animate({scrollTop:0}, 'fast'); return false; }); }); </script> <BODY> <div id="first-post"> <div class="content"><p>This is a test discussion topic</p> </div> </div> <div class="comment"> <h2 class="title"><a href="#1">1st Post</a></h2> <div class="content"> <p>this is 1st reply to the original post</p> </div> <div class="test">1st post second line</div> </div> <div class="comment"> <h2 class="title"><a href="#2">2nd Post</a></h2> <div class="content"> <p>this is 2nd reply to the original post</p> </div> <div class="test">2nd post second line</div> </div> </div> <div class="comment"> <h2 class="title"><a href="#3">3rd Post</a></h2> <div class="content"> <p>this is 3rd reply to the original post</p> </div> <div class="test">3rd post second line</div> </div> </div> </BODY> </HTML>

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  • Jquery hover function doesn't work for a table...

    - by chandru_cp
    I dynamically added rows to a table but it doesn't seem to take hover effects given in jquery... Here is my code, <table id="chkbox" cellpadding="0" cellspacing="2" width="100%" class="table_Style_Border"> <tr> <td style="width:150px" class="grid_header" align="center">RackName</td> <td style="width:150px" class="grid_header" align="center">LibraryName</td> <td style="width:200px" class="grid_header" align="center">LibrarianName</td> <td style="width:200px" class="grid_header" align="center">Location</td> <td style="width:1%" class="grid_header"></td> </tr> <? if(isset($comment)) { echo '<tr><td class=table_label colspan=5>'.$comment.'</td></tr>'; } ?> <?php foreach($rackData as $key => $row) { ?> <?php printf('<tr class="%s">', ($key % 2) ? 'rowcolor' : 'alternaterowcolor'); ?> <td align="left" class="table_label"> <?=$row['rack_name']?> </td> <td align="left" class="table_label"> <?=$row['library_name']?> </td> <td align="center" class="table_label"> <?=$row['librarian']?> </td> <td align="center" class="table_label"> <?=$row['location']?> </td> <td align="center"> <input type="checkbox" name="group" id="group" value="<?=$row['rack_id']?>" onclick="display(this);" > </td> </tr> <? } ?> </table><div align="right" class="pagination"> <?php /*?><?php echo $links;?><?php */?></div> <script type="text/javascript"> $("#chkbox").hover(function() { $(this).addClass("resultshover"); }, function() { $(this).removeClass("resultshover"); }); </script>

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  • How do I connect multiple sortable lists to each other in jQuery UI?

    - by Abs
    I'm new to jQuery, and I'm totally struggling with using jQuery UI's sortable. I'm trying to put together a page to facilitate grouping and ordering of items. My page has a list of groups, and each group contains a list of items. I want to allow users to be able to do the following: 1. Reorder the groups 2. Reorder the items within the groups 3. Move the items between the groups The first two requirements are no problem. I'm able to sort them just fine. The problem comes in with the third requirement. I just can't connect those lists to each other. Some code might help. Here's the markup. <ul id="groupsList" class="groupsList"> <li id="group1" class="group">Group 1 <ul id="groupItems1" class="itemsList"> <li id="item1-1" class="item">Item 1.1</li> <li id="item1-2" class="item">Item 1.2</li> </ul> </li> <li id="group2" class="group">Group 2 <ul id="groupItems2" class="itemsList"> <li id="item2-1" class="item">Item 2.1</li> <li id="item2-2" class="item">Item 2.2</li> </ul> </li> <li id="group3" class="group">Group 3 <ul id="groupItems3" class="itemsList"> <li id="item3-1" class="item">Item 3.1</li> <li id="item3-2" class="item">Item 3.2</li> </ul> </li> </ul> I was able to sort the lists by putting $('#groupsList').sortable({}); and $('.itemsList').sortable({}); in the document ready function. I tried using the connectWith option for sortable to make it work, but I failed spectacularly. What I'd like to do is have the every groupItemsX list connected to every groupItemsX list but itself. How should I do that?

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  • Converting a list into a select with jquery

    - by Davemof
    I'm trying to convert the following list into a select list so it can be submitted via a form - the element within the lists will become the value of each option: <ul class="selected connected-list ui-sortable" style="height: 279px;"> <li class="ui-helper-hidden-accessible" style=""></li> <li title="Owner Name 1 - " class="ui-state-default ui-element ui-draggable" style="display: block; position: relative; top: 0px; left: 0px;"><span class="ui-icon-arrowthick-2-n-s ui-icon"></span>Owner Name 1 - <em class="thenumber">4.4796E+11</em><a class="action" href="#"><span class="ui-corner-all ui-icon ui-icon-minus"></span></a></li> <li title="David Moffat - " class="ui-state-default ui-element" style="display: block; position: relative; top: 0px; left: 0px;"><span class="ui-icon ui-icon-arrowthick-2-n-s"></span>David Moffat - <em class="thenumber">07730423005</em><a class="action" href="#"><span class="ui-corner-all ui-icon ui-icon-minus"></span></a></li> </ul> This should convert to the following format: <select style="display:none" class="selectoption" name="p_num[]" multiple="multiple"> <option value="">4.4796E+11</option> <option value="">07730423007</option> </select> I have tried the following jquery code, but after many hours I'm pulling my hair out: $('a.sendform').click(function(){ $('ul.selected').each(function() { var $select = $('<select />'); $(this).find('li').each(function() { var $option = $('<option />'); $option.attr('value', $(this).('em')).html($(this).html()); $select.append($option); }); $(this).replaceWith($select); }); }); Any help might save my remaining hair. Many thanks David

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  • jQuery nextUntill id < num or alternative

    - by Volmar
    Hi, i'm using jQuery to show/hide different LI-elements based on their classes. Look at this example. <li id="1" class="fp de1"></li> <li id="2" class="fp de1"><button onclick="hide(2,2);"></li> <li id="3" class="fp de2"><button onclick="hide(3,3);"></li> <li id="4" class="fp de3"><button onclick="hide(4,4);"></li> <li id="5" class="fp de4"></li> <li id="6" class="fp de3"></li> <li id="7" class="fp de3"></li> <li id="8" class="fp de1"><button onclick="hide(8,2);"></li> <li id="9" class="fp de2"><button onclick="hide(9,3);"></li> <li id="10" class="fp de3"><button onclick="hide(10,4);"></li> <li id="11" class="fp de4"></li> You se that some of these have a button with a hide funcion. what i want is that when you press the hide button The following elements the have a highernumber in the .de# class should be hidden untill it reaches a LI with the same .de#-class. so if you press the hide(), i want LIs with ids 3,4,5,6,7 to be hiden. if i press the next on i want 4,5,6,7, and the thirs i want id 5 to be hidden. so this is the Javascript i made for it: function hide(id,de){ var de2 = de-1; $('#'+id).nextUntil('li.de'+de2).hide(); } The problem is that this function is not working exactly as i want. it would work correctly in the first hide()-function and the thirs but not in hide()function number two. here it will hide IDs: 4-8. so i want to do something. so i want the nextuntill() to hide elements untill it reaches a LI-element with the same .de# or a lower .de#. i hope i didn't complicate it to much in my description of the problem. if you have better idea than using nextUntill i'm all ears.

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  • Is there a way to reference a certain class/interface/... by enclosing it with its namespace rather than a using directive "using namespace_name" ?!

    - by Ahmed
    Is there a way to reference a certain class/interface/... by enclosing it with its namespace rather than a using directive "using namespace_name" ?! As, I'm working on a website, which uses SAP .NET connector. I already added a reference for connector ddl, and while referencing its namespace "using namespace_name", or set class namespace to another one rather than connector namespace, I got error regarding connector classes with that error message "The type or namespace couldn't be found, are you missing a using directive or an assembly reference?". But while changing namespace name to connector namespace, everything is going well?! // Set namespace to be IDestinationConfiguration interface namespace. namespace SAP.Middleware.Connector { public class ConnectorConfiguration : IDestinationConfiguration { } } So, connector types forced me to set namespace of class to their namespace! Is this possible? If so, how?

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  • assign a model's attribute through association

    - by justcode
    I'm new to rails and working on a rails app and I'm stuck pondering this issue. I have three models class product < ActiveRecord::Base attr_accessible :name, :issn, :category validates_presence_of :name, :issn, :category validates_numericality_of :issn, :message => "has to be a number" has_many :user_products has_many :users, :through => :user_products end class UserProduct < ActiveRecord::Base attr_accessible :price, :category validates_presence_of :price, :category validates_numericality_of :price, :message = "has to be a number" belongs_to :user belongs_to :product end class user < ActiveRecord::Base # devise authentication here # Setup accessible (or protected) attributes for your model attr_accessible :email, :password, :password_confirmation, :remember_me has_many :user_products has_many :products, :through = :user_products end here is my new.html.erb <div class="MainBodyWrapper"> <div class="span8"> <div id="listBoxWrapper"> <fieldset> <%= form_for(@product, :html => { :class => "form-inline" }, :style => "margin-bottom: 60px" ) do |f| %> <div class="control-group"> <label class="control-label" for="name">name</label> <div class="controls"> <%= f.text_field :price, :class => 'input-xlarge input-name', :id => "name" %> </div> </div> <div class="listingButtons"> <button class="btn btn-info"></i>Add</button> <a class="btn">Upload Pictures (anytime)</a> </div> </fieldset> </div> </div> There are reasons why I want to setup the models this way. So the question is this: I want the user to enter the info for the product in the form but it also involves putting in the price of the product which exists in a different model/table (user_product) that is associated with product. How can I do this? You can see that my form_for uses @product. Any help will be appreciated.

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  • Different meaning in the mysql code?

    - by Emre Saracoglu
    $result=mysql_query("select * from dosyabegeni where veri_id='" . get_custom_field('dwcode') . "'"); Not Working It says the number and the screen, but the application does not work veri_id='" . get_custom_field('dwcode') . "'"); veri_id='" . echo get_custom_field('dwcode') . "'"); Working veri_id='HelloTest'"); veri_id='1234567890'"); veri_id='" . $_GET['test'] . "'"); Main Codes <?php include('/home/emre2010/public_html/EntegreOz/DosyaBegeni/config.php'); $result=mysql_query("select * from dosyabegeni where veri_id='" .get_custom_field('dwcode') . "'"); while($row = mysql_fetch_array($result)) { $sira_id=$row['sira_id']; $veri_id=$row['veri_id']; $begeni=$row['begeni']; ?> <div class="reviewbox"> <div class="summarywrap"> <div class="summarywrapinner"> <div class="summary"> <div class="reviewsection"><div class="rating points"> <a href="#" class="begeni" id="<?php echo $sira_id; ?>"> <span style="color:#fff;" align="center"> <?php echo $begeni; ?> </span> </a> <p class="ratingtext">completed!</p></div> </div><div class="clear"></div> <div class="clear"></div> </div> <div class="ratingsummary"></div> <div class="clear"></div> </div> <div class="clear"></div> </div> What's the problem?

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  • Form value field is visable in localhost but not on live site-how to hide?

    - by Joel
    Hi guys, I'm almost completed moving my first live site to my new xampp setup on localhost. I have a form that uses jquery in the header of the site. It's a bit verbose, but here it is: <div class="outeremailcontainer"> <div id="emailcontainer"> <?php include('verify.php'); ?> <form action="index_success.php" method="post" id="sendEmail" class="email"> <h3 class="register2">Newsletter Signup:</h3> <ul class="forms email"> <li class="name"><label for="yourName">Name: </label> <input type="text" name="yourName" class="info" id="yourName" value="<?= $_POST['yourName']; ?>" /><br /> </li> <li class="city"><label for="yourCity">City: </label> <input type="text" name="yourCity" class="info" id="yourCity" value="<?= $_POST['yourCity']; ?>" /><br /> </li> <li class="email"><label for="emailFrom">Email: </label> <input type="text" name="emailFrom" class="info" id="emailFrom" value="<?= $_POST['emailFrom']; ?>" /> <?php if(isset($emailFromError)) echo '<span class="error">'.$emailFromError.'</span>'; ?> </li> <li class="buttons email"> <button type="submit" id="submit">Send</button> <input type="hidden" name="submitted" id="submitted" value="true" /> </li> </ul> </form> <div class="clearing"> </div> </div> </div> So I am using jQuery (I can include the function if need-be) and it hides fields, etc. The problem is that on the localhost site, the values of the fields are populating the fields. IE: first field has this in the box, etc <?= $_POST['yourName']; ?> It works great in the live site though. Any idea how to fix this? Thanks!

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  • Add a fadein fade out in jQuery, on multiple conditional statements

    - by Matthew Harwood
    Task: On click of li navigation filter show and hide content with a transitional fadein fade out. Problem I'm just guessing and checking on where to place this fadein//fadeout transition. Furthermore, I feel like my code is too inefficiency because I'm using 4 conditional statements. Would stack lead me in creating a solution to improve the overall logic of this script so I can just make a pretty transition :c? LIVE CODE jQuery Script $(document).ready(function () { //attach a single click listener on li elements $('li.navCenter').on('click', function () { // get the id of the clicked li var id = $(this).attr('id'); // match current id with string check then apply filter if (id == 'printInteract') { //reset all the boxes for muliple clicks $(".box").find('.video, .print, .web').closest('.box').show(); $(".box").find('.web, .video').closest('.box').hide(); $(".box").find('.print').show(); } if (id == 'webInteract') { $(".box").find('.video, .print, .web').closest('.box').show(); $(".box").find('.print, .video').closest('.box').hide(); $(".box").find('.web').show(); } if (id == 'videoInteract') { $(".box").find('.video, .print, .web').closest('.box').show(); $(".box").find('.print, .web').closest('.box').hide() $(".box").find('.video').show(); } if (id == 'allInteract') { $(".box").find('.video, .print, .web').closest('.box').show(); } }); HTML Selected <nav> <ul class="navSpaces"> <li id="allInteract" class="navCenter"> <a id="activeAll" class="navBg" href="#"><div class="relativeCenter"><img src="asset/img/logo30px.png" /><h3>all</h3></div></a> </li> <li id="printInteract" class="navCenter"> <a id="activePrint" class="navBg" href="#"><div class="relativeCenter"><img src="asset/img/print.gif" /><h3>print</h3></div></a> </li> <li id="videoInteract" class="navCenter"> <a id="activeVideo" class="navBg" href="#"><div class="relativeCenter"><img src="asset/img/video.gif" /><h3>video</h3></div></a> </li> <li id="webInteract" class="navCenter"> <a id="activeWeb" class="navBg" href="#"><div class="relativeCenter"><img src="asset/img/web.gif" /><h3>web</h3></div></a> </li> </ul> ps. Sorry for the newbie question

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  • Using RIA DomainServices with ASP.NET and MVC 2

    - by Bobby Diaz
    Recently, I started working on a new ASP.NET MVC 2 project and I wanted to reuse the data access (LINQ to SQL) and business logic methods (WCF RIA Services) that had been developed for a previous project that used Silverlight for the front-end.  I figured that I would be able to instantiate the various DomainService classes from within my controller’s action methods, because after all, the code for those services didn’t look very complicated.  WRONG!  I didn’t realize at first that some of the functionality is handled automatically by the framework when the domain services are hosted as WCF services.  After some initial searching, I came across an invaluable post by Joe McBride, which described how to get RIA Service .svc files to work in an MVC 2 Web Application, and another by Brad Abrams.  Unfortunately, Brad’s solution was for an earlier preview release of RIA Services and no longer works with the version that I am running (PDC Preview). I have not tried the RC version of WCF RIA Services, so I am not sure if any of the issues I am having have been resolved, but I wanted to come up with a way to reuse the shared libraries so I wouldn’t have to write a non-RIA version that basically did the same thing.  The classes I came up with work with the scenarios I have encountered so far, but I wanted to go ahead and post the code in case someone else is having the same trouble I had.  Hopefully this will save you a few headaches! 1. Querying When I first tried to use a DomainService class to perform a query inside one of my controller’s action methods, I got an error stating that “This DomainService has not been initialized.”  To solve this issue, I created an extension method for all DomainServices that creates the required DomainServiceContext and passes it to the service’s Initialize() method.  Here is the code for the extension method; notice that I am creating a sort of mock HttpContext for those cases when the service is running outside of IIS, such as during unit testing!     public static class ServiceExtensions     {         /// <summary>         /// Initializes the domain service by creating a new <see cref="DomainServiceContext"/>         /// and calling the base DomainService.Initialize(DomainServiceContext) method.         /// </summary>         /// <typeparam name="TService">The type of the service.</typeparam>         /// <param name="service">The service.</param>         /// <returns></returns>         public static TService Initialize<TService>(this TService service)             where TService : DomainService         {             var context = CreateDomainServiceContext();             service.Initialize(context);             return service;         }           private static DomainServiceContext CreateDomainServiceContext()         {             var provider = new ServiceProvider(new HttpContextWrapper(GetHttpContext()));             return new DomainServiceContext(provider, DomainOperationType.Query);         }           private static HttpContext GetHttpContext()         {             var context = HttpContext.Current;   #if DEBUG             // create a mock HttpContext to use during unit testing...             if ( context == null )             {                 var writer = new StringWriter();                 var request = new SimpleWorkerRequest("/", "/",                     String.Empty, String.Empty, writer);                   context = new HttpContext(request)                 {                     User = new GenericPrincipal(new GenericIdentity("debug"), null)                 };             } #endif               return context;         }     }   With that in place, I can use it almost as normally as my first attempt, except with a call to Initialize():     public ActionResult Index()     {         var service = new NorthwindService().Initialize();         var customers = service.GetCustomers();           return View(customers);     } 2. Insert / Update / Delete Once I got the records showing up, I was trying to insert new records or update existing data when I ran into the next issue.  I say issue because I wasn’t getting any kind of error, which made it a little difficult to track down.  But once I realized that that the DataContext.SubmitChanges() method gets called automatically at the end of each domain service submit operation, I could start working on a way to mimic the behavior of a hosted domain service.  What I came up with, was a base class called LinqToSqlRepository<T> that basically sits between your implementation and the default LinqToSqlDomainService<T> class.     [EnableClientAccess()]     public class NorthwindService : LinqToSqlRepository<NorthwindDataContext>     {         public IQueryable<Customer> GetCustomers()         {             return this.DataContext.Customers;         }           public void InsertCustomer(Customer customer)         {             this.DataContext.Customers.InsertOnSubmit(customer);         }           public void UpdateCustomer(Customer currentCustomer)         {             this.DataContext.Customers.TryAttach(currentCustomer,                 this.ChangeSet.GetOriginal(currentCustomer));         }           public void DeleteCustomer(Customer customer)         {             this.DataContext.Customers.TryAttach(customer);             this.DataContext.Customers.DeleteOnSubmit(customer);         }     } Notice the new base class name (just change LinqToSqlDomainService to LinqToSqlRepository).  I also added a couple of DataContext (for Table<T>) extension methods called TryAttach that will check to see if the supplied entity is already attached before attempting to attach it, which would cause an error! 3. LinqToSqlRepository<T> Below is the code for the LinqToSqlRepository class.  The comments are pretty self explanatory, but be aware of the [IgnoreOperation] attributes on the generic repository methods, which ensures that they will be ignored by the code generator and not available in the Silverlight client application.     /// <summary>     /// Provides generic repository methods on top of the standard     /// <see cref="LinqToSqlDomainService&lt;TContext&gt;"/> functionality.     /// </summary>     /// <typeparam name="TContext">The type of the context.</typeparam>     public abstract class LinqToSqlRepository<TContext> : LinqToSqlDomainService<TContext>         where TContext : System.Data.Linq.DataContext, new()     {         /// <summary>         /// Retrieves an instance of an entity using it's unique identifier.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <param name="keyValues">The key values.</param>         /// <returns></returns>         [IgnoreOperation]         public virtual TEntity GetById<TEntity>(params object[] keyValues) where TEntity : class         {             var table = this.DataContext.GetTable<TEntity>();             var mapping = this.DataContext.Mapping.GetTable(typeof(TEntity));               var keys = mapping.RowType.IdentityMembers                 .Select((m, i) => m.Name + " = @" + i)                 .ToArray();               return table.Where(String.Join(" && ", keys), keyValues).FirstOrDefault();         }           /// <summary>         /// Creates a new query that can be executed to retrieve a collection         /// of entities from the <see cref="DataContext"/>.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <returns></returns>         [IgnoreOperation]         public virtual IQueryable<TEntity> GetEntityQuery<TEntity>() where TEntity : class         {             return this.DataContext.GetTable<TEntity>();         }           /// <summary>         /// Inserts the specified entity.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <param name="entity">The entity.</param>         /// <returns></returns>         [IgnoreOperation]         public virtual bool Insert<TEntity>(TEntity entity) where TEntity : class         {             //var table = this.DataContext.GetTable<TEntity>();             //table.InsertOnSubmit(entity);               return this.Submit(entity, null, DomainOperation.Insert);         }           /// <summary>         /// Updates the specified entity.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <param name="entity">The entity.</param>         /// <returns></returns>         [IgnoreOperation]         public virtual bool Update<TEntity>(TEntity entity) where TEntity : class         {             return this.Update(entity, null);         }           /// <summary>         /// Updates the specified entity.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <param name="entity">The entity.</param>         /// <param name="original">The original.</param>         /// <returns></returns>         [IgnoreOperation]         public virtual bool Update<TEntity>(TEntity entity, TEntity original)             where TEntity : class         {             if ( original == null )             {                 original = GetOriginal(entity);             }               var table = this.DataContext.GetTable<TEntity>();             table.TryAttach(entity, original);               return this.Submit(entity, original, DomainOperation.Update);         }           /// <summary>         /// Deletes the specified entity.         /// </summary>         /// <typeparam name="TEntity">The type of the entity.</typeparam>         /// <param name="entity">The entity.</param>         /// <returns></returns>         [IgnoreOperation]         public virtual bool Delete<TEntity>(TEntity entity) where TEntity : class         {             //var table = this.DataContext.GetTable<TEntity>();             //table.TryAttach(entity);             //table.DeleteOnSubmit(entity);               return this.Submit(entity, null, DomainOperation.Delete);         }           protected virtual bool Submit(Object entity, Object original, DomainOperation operation)         {             var entry = new ChangeSetEntry(0, entity, original, operation);             var changes = new ChangeSet(new ChangeSetEntry[] { entry });             return base.Submit(changes);         }           private TEntity GetOriginal<TEntity>(TEntity entity) where TEntity : class         {             var context = CreateDataContext();             var table = context.GetTable<TEntity>();             return table.FirstOrDefault(e => e == entity);         }     } 4. Conclusion So there you have it, a fully functional Repository implementation for your RIA Domain Services that can be consumed by your ASP.NET and MVC applications.  I have uploaded the source code along with unit tests and a sample web application that queries the Customers table from inside a Controller, as well as a Silverlight usage example. As always, I welcome any comments or suggestions on the approach I have taken.  If there is enough interest, I plan on contacting Colin Blair or maybe even the man himself, Brad Abrams, to see if this is something worthy of inclusion in the WCF RIA Services Contrib project.  What do you think? Enjoy!

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  • Static vs Singleton in C# (Difference between Singleton and Static)

    - by Jalpesh P. Vadgama
    Recently I have came across a question what is the difference between Static and Singleton classes. So I thought it will be a good idea to share blog post about it.Difference between Static and Singleton classes:A singleton classes allowed to create a only single instance or particular class. That instance can be treated as normal object. You can pass that object to a method as parameter or you can call the class method with that Singleton object. While static class can have only static methods and you can not pass static class as parameter.We can implement the interfaces with the Singleton class while we can not implement the interfaces with static classes.We can clone the object of Singleton classes we can not clone the object of static classes.Singleton objects stored on heap while static class stored in stack.more at my personal blog: dotnetjalps.com

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  • Training on Demand Certification Packages for DBAs

    - by Antoinette O'Sullivan
    The demand for Database Administrators continues to grow.*Almost two-thirds of IT hiring managers indicate that they highly value certifications in validatingIT skills and expertise.** * Job satisfaction and DBA work growth rate: CNN Money's 2011 Best Jobs in America survey.** Survey among nearly 1,700 respondents by CompTIA, the nonprofit trade association for the IT industry, cited in Certification Magazine, Feb. 14 th., 2012. Get Certified with Training on DemandAre you an experienced Database professional eager to achieve certification?Is time your most precious resource?Then try our new Training On Demand Certification Value Package with 20% discount. These all-in-one packages give you everything you need to get certified with success: Why Training On Demand:  Expert training from Oracle’s top instructors Sophisticated streaming video recording Available for 90 days, 24 hours a day, 7 days a week White boarding and training labs for hands-on experience Start, stop, pause, jump or rewind sections of the course as needed  Oracle University instructor Q&A  A full-text search leads to the right video fragment in a matter of seconds. Watch this demo to see how it works. Additional Certification resources: Benefits of Oracle Certification Database Certification Paths Available Database Certification Exams Getting certified has never been easier!For assistance contact your local Oracle University Service Desk. Many organizations deploy both Oracle Database and MySQL side by side to serve different needs, and as a database professional you can find training courses on both topics at Oracle University! Check out the upcoming Oracle Database 11g training courses and MySQL training courses. Even if you're only managing Oracle Databases at this point of time, getting familiar with MySQL Database will broaden your career path with growing job demand. These Value Packages are also available with the following training formats: In-Class, Live Virtual Class and Self Study: MySQL Database Administration Value Packages Your Savings plus get a FREE Retake  save 5% save 20% save 20% save 20%   In Class Edition Live Virtual Class Edition Self-Study Edition Training On Demand MySQL Database Administrator Certification Value Package View Package View Package View Package View Package MySQL Developer Value Packages Your Savings plus get a FREE Retake  save 5% save 20% save 20% save 20%   In Class Edition Live Virtual Class Edition Self-Study Edition Training On Demand       MySQL Developer Certification Value Package View Package View Package     Oracle Database 10g Value Packages Your Savings plus get a FREE Retake  save 5% save 20% save 20% save 20%   In Class Edition Live Virtual Class Edition Self-Study Edition Training On Demand Oracle Database 10g Administrator Certified Associate Certification Value Package View Package View Package View Package   Oracle Database 10g Administrator Certified Professional Certification Value Package View Package View Package View Package   Oracle Database 11g Value Packages Your Savings plus get a FREE Retake  save 5% save 20% save 20% save 20%   In Class Edition Live Virtual Class Edition Self-Study Edition Training On Demand Oracle Database 11g Administrator Certified Associate Certification Value Package View Package View Package View Package View Package Oracle Database 11g Administrator Certified Professional Certification Value Package View Package View Package View Package View Package Exam Prep Seminar Value Package: Oracle Database Admin 1       View Package Oracle Database 11g Administrator Certified Professional UPGRADE Certification Value Package       View Package Oracle Real Application Clusters 11g and Grid Infrastructure Administraton Certified Expert Certification Value Package       View Package Exam Prep Seminar Value Package: Oracle Database Admin 2        View Package Exam Prep Seminar Value Package: Oracle RAC 11g and Grid Infrastructure Administration       View Package Exam Prep Seminar Value Package: Upgrade Oracle Certified Professional (OCP) to Oracle Database 11g       View Package SQL and PL/SQL Value Packages Your Savings plus get a FREE Retake  save 5% save 20% save 20% save 20%   In Class Edition Live Virtual Class Edition Self-Study Edition Training On Demand Oracle Database Sql Expert Certification Value Package View Package View Package View Package View Package Exam Prep Seminar Value Package: Oracle Database SQL       View Package View our Certification Value Packages Mention this code at the time of booking: E1245 Connect For a full list of MySQL Training courses and events, go to http://oracle.com/education/mysql.

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  • To ref or not to ref

    - by nmarun
    So the question is what is the point of passing a reference type along with the ref keyword? I have an Employee class as below: 1: public class Employee 2: { 3: public string FirstName { get; set; } 4: public string LastName { get; set; } 5:  6: public override string ToString() 7: { 8: return string.Format("{0}-{1}", FirstName, LastName); 9: } 10: } In my calling class, I say: 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: }   After having a look at the code, you’ll probably say, Well, an instance of a class gets passed as a reference, so any changes to the instance inside the CallSomeMethod, actually modifies the original object. Hence the output will be ‘John-Doe’ on the first call and ‘Smith-Doe’ on the second. And you’re right: So the question is what’s the use of passing this Employee parameter as a ref? 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: } The output is still the same: Ok, so is there really a need to pass a reference type using the ref keyword? I’ll remove the ‘ref’ keyword and make one more change to the CallSomeMethod method. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } In line 17 you’ll see I’ve ‘new’d up the incoming Employee parameter and then set its properties to new values. The output tells me that the original instance of the Employee class does not change. Huh? But an instance of a class gets passed by reference, so why did the values not change on the original instance or how do I keep the two instances in-sync all the times? Aah, now here’s the answer. In order to keep the objects in sync, you pass them using the ‘ref’ keyword. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } Viola! Now, to prove it beyond doubt, I said, let me try with another reference type: string. 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(ref name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(ref string name) 12: { 13: name = "def"; 14: } 15: } The output was as expected, first ‘abc’ and then ‘def’ - proves the 'ref' keyword works here as well. Now, what if I remove the ‘ref’ keyword? The output should still be the same as the above right, since string is a reference type? 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(string name) 12: { 13: name = "def"; 14: } 15: } Wrong, the output shows ‘abc’ printed twice. Wait a minute… now how could this be? This is because string is an immutable type. This means that any time you modify an instance of string, new memory address is allocated to the instance. The effect is similar to ‘new’ing up the Employee instance inside the CallSomeMethod in the absence of the ‘ref’ keyword. Verdict: ref key came to the rescue and saved the planet… again!

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  • Tic Tac Toe Winner in Javascript and html [closed]

    - by Yehuda G
    I am writing a tic tac toe game using html, css, and JavaScript. I have my JavaScript in an external .js file being referenced into the .html file. Within the .js file, I have a function called playerMove, which allows the player to make his/her move and switches between player 'x' and 'o'. What I am trying to do is determine the winner. Here is what I have: each square, when onclick(this), references playerMove(piece). After each move is made, I want to run an if statement to check for the winner, but am unsure if the parameters would include a reference to 'piece' or a,b, and c. Any suggestions would be greatly appreciated. Javascript: var turn = 0; a = document.getElementById("topLeftSquare").innerHTML; b = document.getElementById("topMiddleSquare").innerHTML; c = document.getElementById("topRightSquare").innerHTML; function playerMove(piece) { var win; if(piece.innerHTML != 'X' && piece.innerHTML != 'O'){ if(turn % 2 == 0){ document.getElementById('playerDisplay').innerHTML= "X Plays " + printEquation(1); piece.innerHTML = 'X'; window.setInterval("X", 10000) piece.style.color = "red"; if(piece.innerHTML == 'X') window.alert("X WINS!"); } else { document.getElementById('playerDisplay').innerHTML= "O Plays " + printEquation(1); piece.innerHTML = 'O'; piece.style.color = "brown"; } turn+=1; } html: <div id="board"> <div class="topLeftSquare" onclick="playerMove(this)"> </div> <div class="topMiddleSquare" onclick="playerMove(this)"> </div> <div class="topRightSquare" onclick="playerMove(this)"> </div> <div class="middleLeftSquare" onclick="playerMove(this)"> </div> <div class="middleSquare" onclick="playerMove(this)"> </div> <div class="middleRightSquare" onclick="playerMove(this)"> </div> <div class="bottomLeftSquare" onclick="playerMove(this)"> </div> <div class="bottomMiddleSquare" onclick="playerMove(this)"> </div> <div class="bottomRightSquare" onclick="playerMove(this)"> </div> </div>

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  • BizTalk 2009 - Creating a Custom Functoid Library

    - by StuartBrierley
    If you find that you have a need to created multiple Custom Functoids you may also choose to create a Custom Functoid Library - a single project containing many custom functoids.  As previsouly discussed, the Custom Functoid Wizard can be used to create a project with a new custom functoid inside.  But what if you want to extend this project to include more custom functoids and create your Custom Functoid Library?  First create a Custom Functoid Library project and your first Custom Functoid using the Custom Functoid Wizard. When you open your Custom Functoid Library project in Visual Studio you will see that it contains your custom functoid class file along with its resource file.  One of the items this resource file contains is the ID of the the custom functoid.  Each custom functoid needs a unique ID that is over 6000.  When creating a Custom Functoid Library I would first suggest that you delete the ID from this resource file and instead create a _FunctoidIDs class containing constants for each of your custom functoids.  In this way you can easily see which custom functoid IDs are assigned to which custom functoid and which ID is next in the sequence of availability: namespace MyCompany.BizTalk.Functoids.TestFunctoids {     class _FunctoidIDs     {         public const int TestFunctoid                       = 6001;     } } You will then need to update the base() function in your existing functoid class to reference these constant values rather than the current resource file. From:    int functoidID;    // This has to be a number greater than 6000    functoidID = System.Convert.ToInt32(resmgr.GetString("FunctoidId"));    this.ID = functoidID; To: this.ID = _FunctoidIDs.TestFunctoid; To create a new custom functoid you can copy the existing custom functoid, renaming the resultant class file as appropriate.  Once it is renamed you will need to change the Class name, ResourceName reference and Base function name in the class code to those of your new custom functoid.  You will also need to create a new constant value in the _FunctoidIDs class and update the ID reference in your code to match this.  Assuming that you need some different functionalty from your new  customfunctoid you will need to check or amend the following in your functoid class file: Min and Max connections Functoid Category Input and Output connection types The parameters and functionality of the Execute function To change the appearance of you new custom functoid you will need to check or amend the following in the functoid resource file: Name Description Tooltip Exception Icon You can change the String values by double clicking the resource file and amending the value fields in the string table. To amend the functoid icon you will need to create a 16x16 bitmap image.  Once you have saved this you are then ready to import it into the functoid resource file.  In Visual Studio change the resource view to images, right click the icon and choose import from file. You have now completed your new custom functoid and created a Custom Functoid Library.  You can test your new library of functoids by building the project, copying the resultant DLL to C:\Program Files\Microsoft BizTalk Server 2009\Developer Tools\Mapper Extensions and then resetting the toolbox in Visual Studio.

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  • Master Data Management for Location Data - Oracle Site Hub

    - by david.butler(at)oracle.com
    Most MDM discussions cover key domains such as customer, supplier, product, service, and reference data. It is usually understood that these domains have complex structures and hundreds if not thousands of attributes that need governing. Location, on the other hand, strikes most people as address data. How hard can that be? But for many industries, locations are complex, and site information is critical to efficient operations and relevant analytics. Retail stores and malls, bank branches, construction sites come to mind. But one of the best industries for illustrating the power of a site mastering application is Oil & Gas.   Oracle's Master Data Management solution for location data is the Oracle Site Hub. It is a location mastering solution that enables organizations to centralize site and location specific information from heterogeneous systems, creating a single view of site information that can be leveraged across all functional departments and analytical systems.   Let's take a look at the location entities the Oracle Site Hub can manage for the Oil & Gas industry: organizations, property, land, buildings, roads, oilfield, service center, inventory site, real estate, facilities, refineries, storage tanks, vendor locations, businesses, assets; project site, area, well, basin, pipelines, critical infrastructure, offshore platform, compressor station, gas station, etc. Any site can be classified into multiple hierarchies, like organizational hierarchy, operational hierarchy, geographic hierarchy, divisional hierarchies and so on. Any site can also be associated to multiple clusters, i.e. collections of sites, and these can be used as a foundation for driving reporting, analysis, organize daily work, etc. Hierarchies can also be used to model entities which are structured or non-structured collections of nodes, like for example routes, pipelines and more. The User Defined Attribute Framework provides the needed infrastructure to add single row attributes groups like well base attributes (well IDs, well type, well structure and key characterizing measures, and more) and well geometry, and multi row attribute groups like well applications, permits, production data, activities, operations, logs, treatments, tests, drills, treatments, and KPIs. Site Hub can also model areas, lands, fields, basins, pools, platforms, eco-zones, and stratigraphic layers as specific sites, tracking their base attributes, aliases, descriptions, subcomponents and more. Midstream entities (pipelines, logistic sites, pump stations) and downstream entities (cylinders, tanks, inventories, meters, partner's sites, routes, facilities, gas stations, and competitor sites) can also be easily modeled, together with their specific attributes and relationships. Site Hub can store any type of unstructured data associated to a site. This could be stored directly or on an external content management solution, like Oracle Universal Content Management. Considering a well, for example, Site Hub can store any relevant associated multimedia file such as: CAD drawings of the well profile, structure and/or parts, engineering documents, contracts, applications, permits, logs, pictures, photos, videos and more. For any site entity, Site Hub can associate all the related assets and equipments at the site, as well as all relationships between sites, between a site and multiple parties, and between a site and any purchasable or sellable item, over time. Items can be equipment, instruments, facilities, services, products, production entities, production facilities (pipelines, batteries, compressor stations, gas plants, meters, separators, etc.), support facilities (rigs, roads, transmission or radio towers, airstrips, etc.), supplier products and services, catalogs, and more. Items can just be associated to sites using standard Site Hub features, or they can be fully mastered by implementing Oracle Product Hub. Site locations (addresses or geographical coordinates) are also managed with out-of-the-box address geo-coding capabilities coupled with Google Maps integration to deliver powerful mapping capabilities and spatial data analysis. Locations can be shared between different sites. Centered on the site location, any site can also have associated areas. Site Hub can master any site location specific information, like for example cadastral, ownership, jurisdictional, geological, seismic and more, and any site-centric area specific information, like for example economical, political, risk, weather, logistic, traffic information and more. Now if anyone ever asks you why locations need MDM, think about how all these Oil & Gas entities and attributes would translate into your business locations. To learn more about Oracle's full MDM solution for the digital oil field, here is a link to Roberto Negro's outstanding whitepaper: Oracle Site Master Data Management for mastering wells and other PPDM entities in a digital oilfield context  

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  • Star rating not showing in rich snippets

    - by Danny R
    We've recently been doing a lot of work on our site's SEO (www.betterthanreviews.com). We recently did a push to update the rich snippets breadcrumb, meta description, and star rating. After giving Google some time to index the site, it has updated the breadcrumbs and meta descriptions for our review pages, but the stars are still not showing. This is currently how it appears on a Google search (link to the actual page: http://www.betterthanreviews.com/home-security/livewatch): This is what the Rich Snippets is supposed to look like, and how it appears in Google's testing tool: More context: As seen in our html, we are using schema.org language. We initially were using schema.org/Corporation for the site, but we now have the page labeled as schema.org/HomeAndConstructionBusiness because Google will not show star ratings for the Corporation language. However, in our Webmaster Tools, the Structured Data is still showing the Corporation language, which could be a potential issue. Here is a look at some of the coding that we used. But it can be looked at closer by inspecting the element: <div class="aggregate-rating" itemprop="aggregateRating" itemscope="" itemtype="http://schema.org/AggregateRating"> <div class="review row_fluid" itemprop="review" itemscope="" itemtype="http://schema.org/Review"> <div class="row_fluid rating" itemprop="reviewRating" itemscope="" itemtype="http://schema.org/Rating"> <meta content="4.5" itemprop="ratingValue" title="4.5 out of 5 stars" class="star-rating-readonly"> <meta content="2013-12-05" itemprop="datePublished"> <p class="review-headline" itemprop="headline">Way better than my previous system</p> <div> <p class="reviewer" itemprop="author">Scott H. </p> <span class="bullet">•</span> <p class="created_at">2 months ago</p> <p class="content" itemprop="description">I love it! The experience I have had so far is extremely positive. I had another alarm system before and I didn't like it but this one is really nice. I am telling everybody about it.</p> </div> </div> Any suggestions for how to fix this?

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  • Clean way to use mutable implementation of Immutable interfaces for encapsulation

    - by dsollen
    My code is working on some compost relationship which creates a tree structure, class A has many children of type B, which has many children of type C etc. The lowest level class, call it bar, also points to a connected bar class. This effectively makes nearly every object in my domain inter-connected. Immutable objects would be problematic due to the expense of rebuilding almost all of my domain to make a single change to one class. I chose to go with an interface approach. Every object has an Immutable interface which only publishes the getter methods. I have controller objects which constructs the domain objects and thus has reference to the full objects, thus capable of calling the setter methods; but only ever publishes the immutable interface. Any change requested will go through the controller. So something like this: public interface ImmutableFoo{ public Bar getBar(); public Location getLocation(); } public class Foo implements ImmutableFoo{ private Bar bar; private Location location; @Override public Bar getBar(){ return Bar; } public void setBar(Bar bar){ this.bar=bar; } @Override public Location getLocation(){ return Location; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); if(foo!=null) foo.addBar(bar); return foo; } } I felt the basic approach seems sensible, however, when I speak to others they always seem to have trouble envisioning what I'm describing, which leaves me concerned that I may have a larger design issue then I'm aware of. Is it problematic to have domain objects so tightly coupled, or to use the quasi-mutable approach to modifying them? Assuming that the design approach itself isn't inherently flawed the particular discussion which left me wondering about my approach had to do with the presence of business logic in the domain objects. Currently I have my setter methods in the mutable objects do error checking and all other logic required to verify and make a change to the object. It was suggested that this should be pulled out into a service class, which applies all the business logic, to simplify my domain objects. I understand the advantage in mocking/testing and general separation of logic into two classes. However, with a service method/object It seems I loose some of the advantage of polymorphism, I can't override a base class to add in new error checking or business logic. It seems, if my polymorphic classes were complicated enough, I would end up with a service method that has to check a dozen flags to decide what error checking and business logic applies. So, for example, if I wanted to have a childFoo which also had a size field which should be compared to bar before adding par my current approach would look something like this. public class Foo implements ImmutableFoo{ public void addBar(Bar bar){ if(!getLocation().equals(bar.getLocation()) throw new LocationException(); this.bar=bar; } } public interface ImmutableChildFoo extends ImmutableFoo{ public int getSize(); } public ChildFoo extends Foo implements ImmutableChildFoo{ private int size; @Override public int getSize(){ return size; } @Override public void addBar(Bar bar){ if(getSize()<bar.getSize()){ throw new LocationException(); super.addBar(bar); } My colleague was suggesting instead having a service object that looks something like this (over simplified, the 'service' object would likely be more complex). public interface ImmutableFoo{ ///original interface, presumably used in other methods public Location getLocation(); public boolean isChildFoo(); } public interface ImmutableSizedFoo implements ImmutableFoo{ public int getSize(); } public class Foo implements ImmutableSizedFoo{ public Bar bar; @Override public void addBar(Bar bar){ this.bar=bar; } @Override public int getSize(){ //default size if no size is known return 0; } @Override public boolean isChildFoo return false; } } public ChildFoo extends Foo{ private int size; @Override public int getSize(){ return size; } @Override public boolean isChildFoo(); return true; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableSizedFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); service.addBarToFoo(foo, bar); returned foo; } public class Service{ public static void addBarToFoo(Foo foo, Bar bar){ if(foo==null) return; if(!foo.getLocation().equals(bar.getLocation())) throw new LocationException(); if(foo.isChildFoo() && foo.getSize()<bar.getSize()) throw new LocationException(); foo.setBar(bar); } } } Is the recommended approach of using services and inversion of control inherently superior, or superior in certain cases, to overriding methods directly? If so is there a good way to go with the service approach while not loosing the power of polymorphism to override some of the behavior?

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  • Can't adjust brightness on Samsung RV420 with fn keys

    - by nicholascamp
    Typing ls /sys/class/backlight/*/brightness outputs /sys/class/backlight/intel_backlight/brightness /sys/class/backlight/samsung/brightness The max_brightness for the second is 8, but changing it with echo 2 | sudo tee /sys/class/backlight/samsung/brightness doesn't change brightness. I can do it by using intel_backlight: echo 2000 | sudo tee /sys/class/backlight/intel_backlight/brightness (max_brightness: cat /sys/class/backlight/intel_backlight/max_brightness outputs 4648). But I want to do this work with the fn brightness keys, as I always did. I don't know what happened to stop working, maybe the use of +1 monitor and removing it in a wrong time or a system update. I'm using Ubuntu 12.04 64 bits in an Samsung RV420 notebook. Kernel Version is 3.2.0-27-generic. Could you help me? Please tell me what more info should I provide. Thanks!

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  • Is this how dynamic language copes with dynamic requirement?

    - by Amumu
    The question is in the title. I want to have my thinking verified by experienced people. You can add more or disregard my opinion, but give me a reason. Here is an example requirement: Suppose you are required to implement a fighting game. Initially, the game only includes fighters, who can attack each other. Each fighter can punch, kick or block incoming attacks. Fighters can have various fighting styles: Karate, Judo, Kung Fu... That's it for the simple universe of the game. In an OO like Java, it can be implemented similar to this way: abstract class Fighter { int hp, attack; void punch(Fighter otherFighter); void kick(Fighter otherFighter); void block(Figther otherFighter); }; class KarateFighter extends Fighter { //...implementation...}; class JudoFighter extends Fighter { //...implementation... }; class KungFuFighter extends Fighter { //...implementation ... }; This is fine if the game stays like this forever. But, somehow the game designers decide to change the theme of the game: instead of a simple fighting game, the game evolves to become a RPG, in which characters can not only fight but perform other activities, i.e. the character can be a priest, an accountant, a scientist etc... At this point, to make it more generic, we have to change the structure of our original design: Fighter is not used to refer to a person anymore; it refers to a profession. The specialized classes of Fighter (KaraterFighter, JudoFighter, KungFuFighter) . Now we have to create a generic class named Person. However, to adapt this change, I have to change the method signatures of the original operations: class Person { int hp, attack; List<Profession> skillSet; }; abstract class Profession {}; class Fighter extends Profession { void punch(Person otherFighter); void kick(Person otherFighter); void block(Person otherFighter); }; class KarateFighter extends Fighter { //...implementation...}; class JudoFighter extends Fighter { //...implementation... }; class KungFuFighter extends Fighter { //...implementation ... }; class Accountant extends Profession { void calculateTax(Person p) { //...implementation...}; void calculateTax(Company c) { //...implementation...}; }; //... more professions... Here are the problems: To adapt to the method changes, I have to fix the places where the changed methods are called (refactoring). Every time a new requirement is introduced, the current structural design has to be broken to adapt the changes. This leads to the first problem. Rigid structure makes it hard for code reuse. A function can only accept the predefined types, but it cannot accept future unknown types. A written function is bound to its current universe and has no way to accommodate to the new types, without modifications or rewrite from scratch. I see Java has a lot of deprecated methods. OO is an extreme case because it has inheritance to add up the complexity, but in general for statically typed language, types are very strict. In contrast, a dynamic language can handle the above case as follow: ;;fighter1 punch fighter2 (defun perform-punch (fighter1 fighter2) ...implementation... ) ;;fighter1 kick fighter2 (defun perform-kick (fighter1 fighter2) ...implementation... ) ;;fighter1 blocks attacks from fighter2 (defun perform-block (fighter1 fighter2) ...implementation... ) fighter1 and fighter2 can be anything as long as it has the required data for calculation; or methods (duck typing). You don't have to change from the type Fighter to Person. In the case of Lisp, because Lisp only has a single data structure: list, it's even easier to adapt to changes. However, other dynamic languages can have similar behaviors as well. I work primarily with static languages (mainly C and Java, but working with Java was a long time ago). I started learning Lisp and some other dynamic languages this year. I can see how it helps improving my productivity.

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  • Engine Rendering pipeline : Making shaders generic

    - by fakhir
    I am trying to make a 2D game engine using OpenGL ES 2.0 (iOS for now). I've written Application layer in Objective C and a separate self contained RendererGLES20 in C++. No GL specific call is made outside the renderer. It is working perfectly. But I have some design issues when using shaders. Each shader has its own unique attributes and uniforms that need to be set just before the main draw call (glDrawArrays in this case). For instance, in order to draw some geometry I would do: void RendererGLES20::render(Model * model) { // Set a bunch of uniforms glUniformMatrix4fv(.......); // Enable specific attributes, can be many glEnableVertexAttribArray(......); // Set a bunch of vertex attribute pointers: glVertexAttribPointer(positionSlot, 2, GL_FLOAT, GL_FALSE, stride, m->pCoords); // Now actually Draw the geometry glDrawArrays(GL_TRIANGLES, 0, m->vertexCount); // After drawing, disable any vertex attributes: glDisableVertexAttribArray(.......); } As you can see this code is extremely rigid. If I were to use another shader, say ripple effect, i would be needing to pass extra uniforms, vertex attribs etc. In other words I would have to change the RendererGLES20 render source code just to incorporate the new shader. Is there any way to make the shader object totally generic? Like What if I just want to change the shader object and not worry about game source re-compiling? Any way to make the renderer agnostic of uniforms and attributes etc?. Even though we need to pass data to uniforms, what is the best place to do that? Model class? Is the model class aware of shader specific uniforms and attributes? Following shows Actor class: class Actor : public ISceneNode { ModelController * model; AIController * AI; }; Model controller class: class ModelController { class IShader * shader; int textureId; vec4 tint; float alpha; struct Vertex * vertexArray; }; Shader class just contains the shader object, compiling and linking sub-routines etc. In Game Logic class I am actually rendering the object: void GameLogic::update(float dt) { IRenderer * renderer = g_application->GetRenderer(); Actor * a = GetActor(id); renderer->render(a->model); } Please note that even though Actor extends ISceneNode, I haven't started implementing SceneGraph yet. I will do that as soon as I resolve this issue. Any ideas how to improve this? Related design patterns etc? Thank you for reading the question.

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  • Liskov principle: violation by type-hinting

    - by Elias Van Ootegem
    According to the Liskov principle, a construction like the one below is invalid, as it strengthens a pre-condition. I know the example is pointless/nonsense, but when I last asked a question like this, and used a more elaborate code sample, it seemed to distract people too much from the actual question. //Data models abstract class Argument { protected $value = null; public function getValue() { return $this->value; } abstract public function setValue($val); } class Numeric extends Argument { public function setValue($val) { $this->value = $val + 0;//coerce to number return $this; } } //used here: abstract class Output { public function printValue(Argument $arg) { echo $this->format($arg); return $this; } abstract public function format(Argument $arg); } class OutputNumeric extends Output { public function format(Numeric $arg)//<-- VIOLATION! { $format = is_float($arg->getValue()) ? '%.3f' : '%d'; return sprintf($format, $arg->getValue()); } } My question is this: Why would this kind of "violation" be considered harmful? So much so that some languages, like the one I used in this example (PHP), don't even allow this? I'm not allowed to strengthen the type-hint of an abstract method but, by overriding the printValue method, I am allowed to write: class OutputNumeric extends Output { final public function printValue(Numeric $arg) { echo $this->format($arg); } public function format(Argument $arg) { $format = is_float($arg->getValue()) ? '%.3f' : '%d'; return sprintf($format, $arg->getValue()); } } But this would imply repeating myself for each and every child of Output, and makes my objects harder to reuse. I understand why the Liskov principle exists, don't get me wrong, but I find it somewhat difficult to fathom why the signature of an abstract method in an abstract class has to be adhered to so much stricter than a non-abstract method. Could someone explain to me why I'm not allowed to hind at a child class, in a child class? The way I see it, the child class OutputNumeric is a specific use-case of Output, and thus might need a specific instance of Argument, namely Numeric. Is it really so wrong of me to write code like this?

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  • A strong component keeps everything together

    - by Justin Paul-Oracle
    Most of the times you implement a WebCenter Content based system, you require some sort of customization. Sometimes these customizations need a Java class or two, or libraries (for example, the JavaMail API), or Database Objects (like new tables, views, indexes, etc). I have seen that libraries and Database Objects are usually put in place using manual steps. This means that the library jar files are copied to one of the common classes directory (set in the Content CLASSPATH variable) and/or the database scripts are executed manually. I have also seen people place the custom Java classes in the common classes directory. While this may seem like an easy solution, think about a scenario where you need to disable or uninstall the component or if you have to upgrade or migrate the system. You have to keep these manual steps documented and execute them every time you encounter the above scenarios. It is very common that some of these manual steps are missed when you have multiple teams and people working on the system. Here are a few points to ponder upon: Place all your custom Java classes within your component. Create a new directory, say ${COMPONENT_DIR}/classes, and place your code there. You can choose to bundle all your classes into a jar or you can place the entire class directory structure. Add a path entry to the Build Settings so that it is bundled with the component when you build it. You also need to update the Custom Class Path and the Custom Class Path Load Order under the Advanced Build Settings. This will ensure that the system CLASSPATH is updated to add this new directory. Create a new component for any new library that you want to add. Add the appropriate path entries to the Build Settings so that it is bundled with the component when you build it. You also need to update the Custom Class Path, Custom Class Path Load Order and/or the Custom Library Path under the Advanced Build Settings. Enter a comma separated list of features that this component will provide. When you create other components that will use the features exposed by this component, make sure that you specify a dependency to this library component by specifying the comma separated list of features in the Advanced Build Settings. The component wizard allows you to create custom install/uninstall Java code. The wizard will create a install filter class when you check the “Has Install” checkbox on the “Install/Uninstall Settings” tab. Consider using this filter class to create database objects when you install the component and drop the objects when you uninstall the component. If you do a lot of custom component development, consider creating a install/uninstall Java class, which can execute queries defined within the component. To sum up, whenever you write a new custom component, make sure that you bundle everything within the component.

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  • Where should i organize my matrices in a 3D Game engine?

    - by Need4Sleep
    I'm working with a group of people from around the world to create a game engine(and hopefully a game with it) within the next upcoming years. My first task was writing a camera class for the engine to use in order to add cameras to the scene, position and follow points in the scene. The problem i have is with using matrices for transformations in the class, should i keep matrices separate to each class? such as have the model matrix in the model class, camera matrix in the camera class, or have all matrices placed in one class/chuck? I could see pros and cons for each method, but i wanted to hear some input form a more professional standpoint.

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