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  • How am I able to create A List<T> containing a generic Interface?

    - by Conrad Clark
    I have a List which must contain IInteract Objects. But IInteract is a generic interface which requires 2 type arguments. My main idea is iterate through a list of Objects and "Interact" one with another if they didn't interact yet. So i have this object List<IObject> WorldObjects = new List<IObject>(); and this one: private List<IInteract> = new List<IInteract>(); Except I can't compile the last line because IInteract requires 2 type arguments. But I don't know what the arguments are until I add them. I could add interactions between Objects of Type A and A... or Objects of Type B and C. I want to create "Interaction" classes which do something with the "acting" object and the "target" object, but I want them to be independent from the objects... so I could add an Interaction between for instance... "SuperUltraClass" and... an "integer". Am I using the wrong approach?

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  • How can I bind a simple Javascript array to an MVC3 controller action method?

    - by Sergio Tapia
    Here is the javascript code I use to create the array and send it on it's way: <script type="text/javascript" language="javascript"> $(document).ready(function () { $("#update-cart-btn").click(function() { var items = []; $(".item").each(function () { var productKey = $(this).find("input[name='item.ProductId']").val(); var productQuantity = $(this).find("input[type='text']").val(); items[productKey] = productQuantity; }); $.ajax({ type: "POST", url: "@Url.Action("UpdateCart", "Cart")", data: items, success: function () { alert("Successfully updated your cart!"); } }); }); }); </script> The items object is properly constructed with the values I need. What data type must my object be on the backend of my controller? I tried this but the variable remains null and is not bound. [Authorize] [HttpPost] public ActionResult UpdateCart(object[] items) // items remains null. { // Some magic here. return RedirectToAction("Index"); }

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  • How to get the output of an XslCompiledTransform into an XmlReader?

    - by Graham Clark
    I have an XslCompiledTransform object, and I want the output in an XmlReader object, as I need to pass it through a second stylesheet. I'm getting a bit confused - I can successfully transform some XML and read it using either a StreamReader or an XmlDocument, but when I try an XmlReader, I get nothing. In the example below, stylesheet is my XslCompiledTransform object. The first two Console.WriteLine calls output the correct transformed XML, but the third call gives no XML. I'm guessing it might be that the XmlTextReader is expecting text, so maybe I need to wrap this in a StreamReader..? What am I doing wrong? MemoryStream transformed = new MemoryStream(); stylesheet.Transform(input, args, transformed); transformed.Position = 0; StreamReader s = new StreamReader(transformed); Console.WriteLine("s = " + s.ReadToEnd()); // writes XML transformed.Position = 0; XmlDocument doc = new XmlDocument(); doc.Load(transformed); Console.WriteLine("doc = " + doc.OuterXml); // writes XML transformed.Position = 0; XmlReader reader = new XmlTextReader(transformed); Console.WriteLine("reader = " + reader.ReadOuterXml()); // no XML written

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  • Ruby ROXML - how to get an array to render its xml?

    - by Brian D.
    I'm trying to create a Messages object that inherits Array. The messages will gather a group of Message objects. I'm trying to create an xml output with ROXML that looks like this: <messages> <message> <type></type> <code></code> <body></body> </message> ... </messages> However, I can't figure out how to get the message objects in the Messages object to display in the xml. Here is the code I've been working with: require 'roxml' class Message include ROXML xml_accessor :type xml_accessor :code xml_accessor :body end class Messages < Array include ROXML # I think this is the problem - but how do I tell ROXML that # the messages are in this instance of array? xml_accessor :messages, :as => [Message] def add(message) self << message end end message = Message.new message.type = "error" message.code = "1234" message.body = "This is a test message." messages = Messages.new messages.add message puts messages.length puts messages.to_xml This outputs: 1 <messages/> So, the message object I added to messages isn't getting displayed. Anyone have any ideas? Or am I going about this the wrong way? Thanks for any help.

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  • jquery script that used to work is not working with jquery 1.4.2

    - by Zayatzz
    ... and i cant figure out why. The script is following: <script type="text/javascript" src="http://path/to/js/jquery-1.4.2.min.js"></script> <script type="text/javascript"> function openMediaPlayer() { $('#flashMovie').animate({'height':'333px'}); } function closeMediaPlayer() { $('#flashMovie').animate({'height':'80px'}); } jQuery(function($){ $('#videoholder').bind('mouseenter', function(){ openMediaPlayer(); }); $('#videoholder').bind('mouseleave', function(){ closeMediaPlayer(); }); }); </script> <div id="videoholder" style="height:80px;width:412px;"> <object width="412" height="80" type="application/x-shockwave-flash" id="flashMovie" name="flashMovie" style="height: 80px;" data="http://path/to/Player.swf"><param name="menu" value="false"><param name="bgcolor" value="#666666"><param name="allowFullscreen" value="true"><param name="flashvars" value="playlistURL=http://path/to/Player/data/playlist.xml"></object> </div> pure and simple resizing flash object. It worked with older(1.3.2) jquery verision. The animate just does not work. Can anyone tell me what i should change to get it working again? Alan.

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  • iOS MapKit: Selected MKAnnotation coordinates.

    - by Oh Danny Boy
    Using the code at the following tutorial, http://www.zenbrains.com/blog/en/2010/05/detectar-cuando-se-selecciona-una-anotacion-mkannotation-en-mapa-mkmapview/, I was able to add an observer to each MKAnnotation and receive a notification of selected/deselected states. I am attempting to add a UIView on top of the selection annotation to display relevant information about the location. This information cannot be conveyed in the 2 lines allowed (Title/Subtitle) for the pin's callout. - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context { Annotation *a = (Annotation *)object; // Alternatively attempted using: //Annotation *a = (Annotation *)[mapView.selectedAnnotations objectAtIndex:0]; NSString *action = (NSString *)context; if ([action isEqualToString:ANNOTATION_SELECTED_DESELECTED]) { BOOL annotationSelected = [[change valueForKey:@"new"] boolValue]; if (annotationSelected) { // Actions when annotation selected CGPoint origin = a.frame.origin; NSLog(@"origin (%f, %f) ", origin.x, origin.y); // Test UIView *v = [[UIView alloc] init]; [v setBackgroundColor:[UIColor orangeColor]]; [v setFrame:CGRectMake(origin.x, origin.y , 300, 300)]; [self.view addSubview:v]; [v release]; }else { // Accions when annotation deselected } } } Results using Annotation *a = (Annotation *)object origin (154373.000000, 197135.000000) origin (154394.000000, 197152.000000) origin (154445.000000, 197011.000000) Results using Annotation *a = (Annotation *)[mapView.selectedAnnotations objectAtIndex:0]; origin (0.000000, 0.000000) origin (0.000000, 0.000000) origin (0.000000, 0.000000) The numbers are large. They are not relative to the view (1024 x 768). I believe they are relative to the entire map. How would I be able to detect the exact coordinates relative to the entire view so that I can appropriately position my view?

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  • InvalidCastException when getting Text from a Label referenced by dynamicaly built String, Fix?

    - by Chris
    NET Version: 3.5 Ok, I recieve an error (System.InvalidCastException was unhandled. Message="Unable to cast object of type 'System.Windows.Forms.Control[]' to type 'System.Windows.Forms.Label'.") when trying to get Text from a Label referenced by a dynamicly built string. Here's my situation; I have an array of 250 labels named l1 - l250. What I want to do is loop through them using this while statement: int c = 1; while (c < 251) { string k = "l" + c.ToString(); //dynamic name of Control(Label) object ka = Controls.Find(k, true); string ct = ((Label)ka).Text; //<<Error Occurs Here build = build + ct; c++; } and get the text value of each to build a string named build. I don't get any build errors, just this while debuging. While debuging I can go down to view my local variables. When looking through these, I can view the contents of object ka; it does contain the correct Text value of the correct Label I want to "access". I just don't understand how to get there. The text value is listed under "[0]" which is the only subcatagory for "ka".

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  • Visual Studio IntelliSense - IHideObjectMembers trick doesn't work. What am I missing?

    - by stakx
    The IHideObjectMembers trick can be used e.g. in fluent interface implementations to hide System.Object members from IntelliSense. (If you don't know this trick, you can read up on it via the above link; I'm just repeating the interface's usual declaration here:) using System; using System.ComponentModel; [EditorBrowsable(EditorBrowsableState.Never)] public interface IHideObjectMembers { [EditorBrowsable(EditorBrowsableState.Never)] Type GetType(); [EditorBrowsable(EditorBrowsableState.Never)] int GetHashCode(); [EditorBrowsable(EditorBrowsableState.Never)] string ToString(); [EditorBrowsable(EditorBrowsableState.Never)] bool Equals(object obj); } I'm now supposed to be able to hide System.Object members on another type as follows: public class SomeClass : IHideObjectMembers { ... } or: public class ISomeInterface : IHideObjectMembers { ... } I tried this in both VS 2008 Express and VS 2008 Standard. However, no members are hidden from IntelliSense at all. I have used the EditorBrowsableAttribute in different projects and it always worked well; however, it doesn't work in this particular scenario. If things had worked as expected, I would only have seen the SomeMethodTwo method. Am I missing something?

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  • Why do case class companion objects extend FunctionN?

    - by retronym
    When you create a case class, the compiler creates a corresponding companion object with a few of the case class goodies: an apply factory method matching the primary constructor, equals, hashCode, and copy. Somewhat oddly, this generated object extends FunctionN. scala> case class A(a: Int) defined class A scala> A: (Int => A) res0: (Int) => A = <function1> This is only the case if: There is no manually defined companion object There is exactly one parameter list There are no type arguments The case class isn't abstract. Seems like this was added about two years ago. The latest incarnation is here. Does anyone use this, or know why it was added? It increases the size of the generated bytecode a little with static forwarder methods, and shows up in the #toString() method of the companion objects: scala> case class A() defined class A scala> A.toString res12: java.lang.String = <function0>

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  • Spring MessageSource not being used during validation

    - by Jeremy
    I can't get my messages in messages.properties to be used during Spring validation of my form backing objects. app-config.xml: <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource"> <property name="basename" value="messages" /> </bean> WEB-INF/classes/messages.properties: NotEmpty=This field should not be empty. Form Backing Object: ... @NotEmpty @Size(min=6, max=25) private String password; ... When I loop through all errors in the BindingResult and output the ObjectError's toString I get this: Field error in object 'settingsForm' on field 'password': rejected value []; codes [NotEmpty.settingsForm.password,NotEmpty.password,NotEmpty.java.lang.String,NotEmpty]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [settingsForm.password,password]; arguments []; default message [password]]; default message [may not be empty] As you can see the default message is "may not be empty" instead of my message "This field should not be empty". I do get my correct message if I inject the messageSource into a controller and output this: messageSource.getMessage("NotEmpty", new Object [] {"password"}, "default empty message", null); So why isn't the validation using my messages.properties? I'm running Spring 3.1.1. Thanks!

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  • Dynamically class creating by using Java Reflection, java.lang.ClassNotFoundException

    - by rubby
    Hi all; i want to use reflection in java, i want to do that third class will read the name of the class as String from console. Upon reading the name of the class, it will automatically and dynamically (!) generate that class and call its writeout method. If that class is not read from input, it will not be initialized. I wrote that codes but i am always taking to "java.lang.Class.Not.Found.Exception", and i don't know how i can fix it. Can anyone help me? class class3 { public Object dynamicsinif(String className, String fieldName, String value) throws Exception { Class cls = Class.forName(className,true,null); Object obj = cls.newInstance(); Field fld = cls.getField(fieldName); fld.set(obj, value); return obj; } public void writeout3() { System.out.println("class3"); } } public class Main { public static void main(String[] args) throws Exception { System.out.println("enter the class name : "); BufferedReader reader= new BufferedReader(new InputStreamReader(System.in)); String line=reader.readLine(); String x="Text1"; try{ class3 trycls=new class3(); Object gelen=trycls.dynamicsinif(line, x, "rubby"); Class yeni=(Class)gelen; System.out.println(yeni); }catch(ClassNotFoundException ex){ System.out.print(ex.toString()); } } }

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  • Should I go for Arrays or Objects in PHP in a CouchDB/Ajax app?

    - by karlthorwald
    I find myself converting between array and object all the time in PHP application that uses couchDB and Ajax. Of course I am also converting objects to JSON and back (for sometimes couchdb but mostly Ajax), but this is not so much disturbing my workflow. At the present I have php objects that are returned by the CouchDB modules I use and on the other hand I have the old habbit to return arrays like array("error"="not found","data"=$dataObj) from my functions. This leads to a mixed occurence of real php objects and nested arrays and I cast with (object) or (array) if necessary. The worst thing is that I know more or less by heart what a function returns, but not what type (array or object), so I often run into type errors. My plan is now to always cast arrays to objects before returning from a function. Of course this implies a lot of refactoring. Is this the right way to go? What about the conversion overhead? Other ideas or tips? Edit: Kenaniah's answer suggests I should go the other way, this would mean I'd cast everything to arrays. And for all the Ajax / JSON stuff and also for CouchDB I would use $myarray = json_decode($json_data,$assoc = true); //EDIT: changed to true, whcih is what I really meant Even more work to change all the CouchDB and Ajax functions but in the end I have better code.

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  • Handling selection and deselection of objects in a user interface

    - by Dennis
    I'm writing a small audio application (in Silverlight, but that's not really relevant I suppose), and I'm a struggling with a problem I've faced before and never solved properly. This time I want to get it right. In the application there is one Arrangement control, which contains several Track controls, and every Track can contain AudioObject controls (these are all custom user controls). The user needs to be able to select audio objects, and when these objects are selected they are rendered differently. I can make this happen by hooking into the MouseDown event of the AudioObject control and setting state accordingly. So far so good, but when an audio object is selected, all other audio objects need to be deselected (well, unless the user holds the shift key). Audio objects don't know about other audio objects though, so they have no way to tell the rest to deselect themselves. Now if I would approach this problem like I did the last time I would pass a reference to the Arrangement control in the constructor of the AudioObject control and give the Arrangement control a DeselectAll() method or something like that, which would tell all Track controls to deselect all their AudioObject controls. This feels wrong, and if I apply this strategy to similar issues I'm afraid I will soon end up with every object having a reference to every other object, creating one big tightly coupled mess. It feels like opening the floodgates for poorly designed code. Is there a better way to handle this?

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  • Searching with a UISearchbar is slow and blocking the main thread.

    - by Robert
    I have a Table with over 3000 entries and searching is very slow. At the moment I am doing just like in the 'TableSearch' example code (but without scopes) - (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString { [self filterContentForSearchText: searchString]; // Return YES to cause the search result table view to be reloaded. return YES; } And the filterContentForSearchText method is as follows: - (void) filterContentForSearchText:(NSString*)searchText { // Update the filtered array based on the search text // First clear the filtered array. [filteredListContent removeAllObjects]; // Search the main list whose name matches searchText // add items that match to the filtered array. if (fetchedResultsController.fetchedObjects) { for (id object in fetchedResultsController.fetchedObjects) { NSString* searchTarget = [tableTypeDelegate getStringForSearchFilteringFromObject:object]; if ([searchTarget rangeOfString:searchText options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch)].location != NSNotFound) { [filteredListContent addObject:object]; } } } } My question is twofold: How do can I make the searching process faster? How can I stop the search from blocking the main thread? i.e. stop it preventing the user from typing more characters. For the second part, I tried "performSelector:withObject:afterDelay:" and "cancelPreviousPerformRequests..." without much success. I suspect that I will need to use threading instead, but I do not have much experience with it.

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  • Get a button in itemscontrol and add eventhandler to its click event

    - by rockdale
    I have a custom control shows a customer info with an itemscontrol shows this customer's invoices. within the itemscontrol, I have button, in my code behind I want to wire the button's click event to my host window, but do now know how. //public event RoutedEventHandler ViewDetailClick; public static readonly RoutedEvent ButtonViewClickEvent = EventManager.RegisterRoutedEvent( "ButtonViewClick", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(custitem)); public event RoutedEventHandler ButtonViewClick { add { AddHandler(ButtonViewClickEvent, value); } remove {RemoveHandler(ButtonViewClickEvent, value);} } public override void OnApplyTemplate() { base.OnApplyTemplate(); this.lstInv = GetTemplateChild("lstInv") as ItemsControl; lstInv.ItemContainerGenerator.StatusChanged += new EventHandler(ItemContainerGenerator_StatusChanged); } private void ItemContainerGenerator_StatusChanged(object sender, EventArgs e) { if (lstInv.ItemContainerGenerator.Status == System.Windows.Controls.Primitives.GeneratorStatus.ContainersGenerated) { lstInv.ItemContainerGenerator.StatusChanged -= ItemContainerGenerator_StatusChanged; for (int i = 0; i < this.lstInv.Items.Count; i++) { ContentPresenter c = lstInv.ItemContainerGenerator.ContainerFromItem(lstInv.Items[i]) as ContentPresenter; DataTemplate dt = c.ContentTemplate; Grid grd = dt.LoadContent() as Grid; Button btnView = grd.FindName("btnView") as Button; if (btnView != null) { btnView.Click += new RoutedEventHandler(ButtonView_Click); //btnView.Click+= delegate(object senderObj, RoutedEventArgs eArg) //{ // if (this.ViewDetailClick != null) // { // this.ViewDetailClick(this, eArg); // } //}; } } private void ButtonView_Click(object sender, RoutedEventArgs e) { MessageBox.Show("clicked"); //e.RoutedEvent = ButtonViewClickEvent; //e.Source = sender; //RaiseEvent(e); } I succeed getting the btnView, then attach the click event, but the click event never get fired. Thanks in advance -rockdale

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  • How to fetch populated associated models in CakePHP when calling read()

    - by Code Commander
    I have the following Models: class Site extends AppModel { public $name = "Site"; public $useTable = "site"; public $primaryKey = "id"; public $displayField = 'name'; public $hasMany = array('Item' => array('foreignKey' => 'siteId')); public function canView($userId, $isAdmin = false) { if($isAdmin) { return true; } return array_key_exists($this->id, $allowedSites); } } and class Item extends AppModel { public $name = "Item"; public $useTable = "item"; public $primaryKey = "id"; public $displayField = 'name'; public $belongsTo = array('Site' => array('foreignKey' => 'siteId')); public function canView($userId, $isAdmin = false) { // My problem appears to be the next line: return $this->Site->canView($userId, $isAdmin); } } In my controller I am doing something like this: $result = $this->Item->read(null, $this->request->id); // Verify permissions if(!$this->Item->canView($this->Session->read('userId'), $this->Session->read('isAdmin'))) { $this->httpCodes(403); die('Permission denied.'); } I notice that in Item->canView() $this->data['Site'] is populated with the column data from the site table. But it merely an array and not an object. On the other hand $this->Site is a Site object, but it has not been populated with the column data from the site table like $this->data. What is the proper way to have CakePHP get the associated model as the object and containing the data? Or am I going about this all wrong? Thanks!

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  • I can not use Session In Page_Load and I got error bellow

    - by LostLord
    hi my dear friends .... why i got this error : Object reference not set to an instance of an object. when i put this code in my page_load.: protected void Page_Load(object sender, EventArgs e) { BackEndUtils.OverallLoader(); string Teststr = Session["Co_ID"].ToString(); } ========================================================================== this session is made when user logins to my web site and this session works in other areas... thanks for your attention ========================================================================== thanks for your answers i removed BackEndUtils.OverallLoader(); but error still exists i tried Teststr = Convert.ToString(Session["Co_ID"]); and error disappeared - but i don't know why that session is null in other areas that session works perfectly = such as a button in that form what is the matter? my web page markup is like this : <%@ Page Title="" Language="C#" MasterPageFile="~/Admin/AdminBackend.Master" AutoEventWireup="true" CodeBehind="Personel.aspx.cs" Inherits="Darman.Admin.Personel" Theme="DefaultTheme" %> ================================================================================= i put this code in a button like this : string Teststr = Convert.ToString(Session["Co_ID"]); when i press that button THIS code in page Load(POSTBACK) + IN Button_Click works perfectly and shows me 23 (my Co_ID) But when i run my page in browser (first time) this code in page load shows me null. why? thanks a lot

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  • C# 4.0 'dynamic' doesn't set ref/out arguments

    - by Buu Nguyen
    I'm experimenting with DynamicObject. One of the things I try to do is setting the values of ref/out arguments, as shown in the code below. However, I am not able to have the values of i and j in Main() set properly (even though they are set correctly in TryInvokeMember()). Does anyone know how to call a DynamicObject object with ref/out arguments and be able to retrieve the values set inside the method? class Program { static void Main(string[] args) { dynamic proxy = new Proxy(new Target()); int i = 10; int j = 20; proxy.Wrap(ref i, ref j); Console.WriteLine(i + ":" + j); // Print "10:20" while expect "20:10" } } class Proxy : DynamicObject { private readonly Target target; public Proxy(Target target) { this.target = target; } public override bool TryInvokeMember(InvokeMemberBinder binder, object[] args, out object result) { int i = (int) args[0]; int j = (int) args[1]; target.Swap(ref i, ref j); args[0] = i; args[1] = j; result = null; return true; } } class Target { public void Swap(ref int i, ref int j) { int tmp = i; i = j; j = tmp; } }

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  • c++ - strange problem with polymorphism - cellular automaton

    - by Green
    Hello, I am making "game of life" implementation that, when cell has: two live neighbours I make object of class CCellB two live neighbours I make object of class CCellA when has 3 or <2 I make object of class CCellX (dead) Class CCell is base of CCellA, CCellB, CCellX My problem is: That works fine, until I change new CCell(); to new CCellB();: CCell ***temp = allocateArray(); for(int i = 0; i < n; i++) { for(int j = 0; j < m; j++) { c = arr[i][j]->countAliveNeighbor(); if(c == 3) { temp[i][j] = new CCellA(); temp[i][j]->alive = 1; }else if(c == 2) { temp[i][j] = new CCell(); // HERE, WHEN I CHANGE IT TO CCELLB IT DON'T WORKS temp[i][j]->alive = tab[i][j]->alive; }else if((c >= 4)||(c < 2)) { temp[i][j] = new CCellX(); } } } Then it seems don't work properly... Seems like neighbours are not count properly, Cell with 4,5 neighbours still alive alive var is member of base class - CCell, all is public, please help!

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  • why is OOP hard for me?

    - by netrox
    I have trouble writing OOP in PHP... I understand the concept but I never create classes for my projects... mainly because it's often a small project and nothing complex. But when I read OOP, it seems more difficult to code than writing simple procedural statements. It also seems to take a lot of room as well with so many empty abstract classes and that can be easily lost in the land of objects... it's becoming like a junkyard to me. Also, I noticed that virtually all instructions on how to use OOP use "car" or "cat" or "dog" analogies. Hello... we're not dealing with animals or cars... we're dealing with windows or consoles. You can talk about analogies to death and I will never learn. What I want is see a code that's written to show how objects are created - not, "aCow-moo!" For example, I want to see a browser window object displaying say... three inputs. I want to see an "object" created to output a window with three inputs then I want to see how overriding works, like change the window object to display only two inputs instead of three inputs. I think that would make learning more easy, wouldn't it? Any recommended tutorials of that nature instead of quacks, moos, and woofs.

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  • Checking instance of non-class constrained type parameter for null in generic method

    - by casperOne
    I currently have a generic method where I want to do some validation on the parameters before working on them. Specifically, if the instance of the type parameter T is a reference type, I want to check to see if it's null and throw an ArgumentNullException if it's null. Something along the lines of: // This can be a method on a generic class, it does not matter. public void DoSomething<T>(T instance) { if (instance == null) throw new ArgumentNullException("instance"); Note, I do not wish to constrain my type parameter using the class constraint. I thought I could use Marc Gravell's answer on "How do I compare a generic type to its default value?", and use the EqualityComparer<T> class like so: static void DoSomething<T>(T instance) { if (EqualityComparer<T>.Default.Equals(instance, null)) throw new ArgumentNullException("instance"); But it gives a very ambiguous error on the call to Equals: Member 'object.Equals(object, object)' cannot be accessed with an instance reference; qualify it with a type name instead How can I check an instance of T against null when T is not constrained on being a value or reference type?

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  • How do I link one listview to another to create a football league table?

    - by Richard Nixon
    Hi I am creating a football system in windows forms c#. I have one listview where data is entered. I have 4 columns, 2 with team names linked to combo boxes and 2 with the scores linked to numericupdown controls. There are 3 buttons to add the results, Remove and clear. the code is below: private void addButton_Click(object sender, EventArgs e) { { ListViewItem item = new ListViewItem(comboBox1.SelectedItem.ToString()); item.SubItems.Add(numericUpDown1.Value.ToString()); item.SubItems.Add(numericUpDown2.Value.ToString()); item.SubItems.Add(comboBox2.SelectedItem.ToString()); listView1.Items.Add(item); } } private void clearButton_Click(object sender, EventArgs e) { listView1.Items.Clear(); } private void removeButton_Click(object sender, EventArgs e) { foreach (ListViewItem itemSelected in listView1.SelectedItems) { listView1.Items.Remove(itemSelected); } } I have another listview that i want to link the first one to. The second one is a usual english football league table and i want to use maths to add up the games played and the points etc. please help. cheers

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  • Constructor and Destructors in C++ [Not a question] [closed]

    - by Jack
    I am using gcc. Please tell me if I am wrong - Lets say I have two classes A & B class A { public: A(){cout<<"A constructor"<<endl;} ~A(){cout<<"A destructor"<<endl;} }; class B:public A { public: B(){cout<<"B constructor"<<endl;} ~B(){cout<<"B destructor"<<endl;} }; 1) The first line in B's constructor should be a call to A's constructor ( I assume compiler automatically inserts it). Also the last line in B's destructor will be a call to A's destructor (compiler does it again). Why was it built this way? 2) When I say A * a = new B(); compiler creates a new B object and checks to see if A is a base class of B and if it is it allows 'a' to point to the newly created object. I guess that is why we don't need any virtual constructors. ( with help from @Tyler McHenry , @Konrad Rudolph) 3) When I write delete a compiler sees that a is an object of type A so it calls A's destructor leading to a problem which is solved by making A's destructor virtual. As user - Little Bobby Tables pointed out to me all destructors have the same name destroy() in memory so we can implement virtual destructors and now the call is made to B's destructor and all is well in C++ land. Please comment.

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  • WPF BackGroundWorker ProgressChanged not updating textblock

    - by user354469
    I have the method below that seems to behaving strangely. The ProgressChanged and RunWorkerCompleted seem to be updating themselves at the same time. If I comment out the RunWorkerCompleted code which updates the Textblock I see the ProgressChanged taking effect after the data is transferred. What am i doing wrong here? I obviously want the textblock to show I'm getting data, then change when I have finished getting the data. public void GetAppointmentsBackground() { System.Windows.Threading.Dispatcher webServiceDispatcher = this.Dispatcher; worker = new BackgroundWorker(); worker.WorkerReportsProgress = true; worker.DoWork += delegate(object sender, DoWorkEventArgs args) { GetAppointmentsForDayDelegate getAppt = new GetAppointmentsForDayDelegate(GetAppointmentsForDay); webServiceDispatcher.BeginInvoke(getAppt); (sender as BackgroundWorker).ReportProgress(25); }; worker.ProgressChanged += delegate(object s, ProgressChangedEventArgs args) { txtMessages.Text = "Contacting Server"; }; worker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args) { txtMessages.Text = "Completed Successfully"; }; worker.RunWorkerAsync(); }

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  • Rails rake test returns an error message

    - by eakkas
    I am a rails newbie and receive the following message when I run rake test. This is a an application based on rails community engine. I tried creating a test application just to make sure that my gems etc. are fine and I am able to run rake test successfully in that application. It would be great if someone could shed a light on what is going wrong... /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/whiny_nil.rb:52:in `method_missing': undefined method `merge' for nil:NilClass (NoMethodError) from /home/eakkas/NetBeansProjects/hello_ce/vendor/plugins/community_engine/app/controllers/users_controller.rb:17 from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:158:in `require_without_desert' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:8:in `require' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:32:in `__each_matching_file' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:7:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:265:in `require_or_load' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:27:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `each' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:136:in `require_dependency' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:414:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:197:in `process' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `send' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `run'

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