Search Results

Search found 54446 results on 2178 pages for 'struct vs class'.

Page 633/2178 | < Previous Page | 629 630 631 632 633 634 635 636 637 638 639 640  | Next Page >

  • Is base method able to use derived base data members?

    - by iTayb
    Lets assume we have the following code: abstract class Base1 { protected int num; } class Der1:Base1 { protected Color color; protected string name; } class Der2:Base1 { protected DateTime dthen; } and so on. An array of base1 type exists and includes many objects created out of classes that are derived from base1. Is it possible to define the toString() method in the base class only? something like: public override string toString() { if (this is Der1) return "num = " + this.num + "color = " + this.color.toString() + " name = " this.name; if (this is Der2) return "num = " + this.num + "dthen = " + this.dthen.toString(); // and so on ... } Thank you very much :) P.S. This is not an homework question. I've just wondered about.

    Read the article

  • C++ code snippet for a new baby greeting card

    - by uvts_cvs
    A friend of mine sent me this code snippet to celebrate his new baby birth: void new_baby_name() { father_surname++; } The snippet is from his point of view, he is the father and the new baby get the surname from him. I answered with this: class father_name {}; class mother_name {}; class new_baby_name: public father_name, public mother_name {}; but I am not fully satisfied of my answer...

    Read the article

  • Singelton restricted to instance of dll

    - by codeySmurf
    If I create a singleton class in the context of a dll, the singleton class is instantiated once and used by all instances of the dll. I am using a dll as a plug-in for an application. Now the following thing came to my mind: If I use a singleton Class, it will be shared across multiple instances of the plug-in. However, this makes it difficult to manage the lifetime of the singleton class efficiently. The only way I could think of would be to use a reference count and to make the singleton delete its self when the reference count is 0. Does anyone have any better ideas on that? Is there any good way to restrict the singleton object to one instance of the dll? Language is c++

    Read the article

  • How do I wrap a repeatbale set of elements in jQuery?

    - by Globalz
    In jQuery how would I go about wrapping a repeatable set of elements with a div? For example I have: img h4 p img h4 p img h4 p I need to wrap each img, h4, p set with a div class="container". So it will look like: <div> class="container" img h4 p </div> <div> class="container" img h4 p </div> <div> class="container" img h4 p </div> Any ideas on how I can achieve this as its driving me nuts! I keep getting nested div.containers! Thanks!

    Read the article

  • Generic Func<> as parameter to base method

    - by WestDiscGolf
    I might be losing the plot, but I hope someone can point me in the right direction. What am I trying to do? I'm trying to write some base methods which take Func< and Action so that these methods handle all of the exception handling etc. so its not repeated all over the place but allow the derived classes to specify what actions it wants to execute. So far this is the base class. public abstract class ServiceBase<T> { protected T Settings { get; set; } protected ServiceBase(T setting) { Settings = setting; } public void ExecAction(Action action) { try { action(); } catch (Exception exception) { throw new Exception(exception.Message); } } public TResult ExecFunc<T1, T2, T3, TResult>(Func<T1, T2, T3, TResult> function) { try { /* what goes here?! */ } catch (Exception exception) { throw new Exception(exception.Message); } } } I want to execute an Action in the following way in the derived class (this seems to work): public void Delete(string application, string key) { ExecAction(() => Settings.Delete(application, key)); } And I want to execute a Func in a similar way in the derived class but for the life of me I can't seem to workout what to put in the base class. I want to be able to call it in the following way (if possible): public object Get(string application, string key, int? expiration) { return ExecFunc(() => Settings.Get(application, key, expiration)); } Am I thinking too crazy or is this possible? Thanks in advance for all the help.

    Read the article

  • Quick question regarding MVC framework for a java game

    - by Jason
    I have a question regarding the use of the MVC framework for a blackjack game im writing in java. As I understand, my model would be a class that stores the state of the game, and more specifically, each players hand. Within the model class, I would have an array of listeners, which would be notified each time the game state changes (ie a player has drawn a new card). These listeners would be my viewer, which is the class that handles the display of the game. This class would implement the ActionListener interface, and each time the model changes, it would call/"notify" my viewer's actionPerformed method. My question is as follows: I intend to have two JPanels, each devoted to displaying the respective player's hand. As a player draws a new card, a new ImageIcon would be added to the panel. My question is how would the viewer class know what card has been added to the player's hand? I suppose I could store the player's hand before a notify event, and then upon the notification event, compare the new state with the old, to find out what has changed. I'm a complete novice here, so I could be completely wrong, but it seems a bit tedious to do this. Is there a more efficient/common way of detecting what has changed in the model between the before and after state? Another solution would be to redraw the entire panel each time the notification occurs? Would this be a better idea?

    Read the article

  • Hibernate reverse engineering

    - by EugeneP
    I have a structure where the main table is USER, other tables include CATEGORY (contains user_id). What I got after the standard reverse engineering procedure was: the class User contained a collection of categories, the class Category didn't contain the foreign key (user_id) but it did contain the User object. Why did it not contain the foreign key as a class property? And how do I join these two tables in HQL without that glue? HQL - please explain this part.

    Read the article

  • Tracking changed (unsaved) objects

    - by Eric
    I have a class which is serialized to and from an XML file when the user decided to open or save. I'm trying to add the typical functionality where when they try to close the form with un-saved changes the form warns them and gives them the option of saving before closing. I've added a HasUnsavedChanges property to my class, which my form checks before closing. However, it's a little annoying that my properties have changed from something like this .. public string Name { get; set; } to this... private string _Name; public string Name { get { return _Name; } set { this._Name = value; this.HasUnsavedChanges = true; } } Is there a better way to track changes to an instance of a class? For example is there some standard way I can "hash" an instance of a class into a value that I can use to compare the most recent version with the saved version without mucking up every property in the class?

    Read the article

  • how can i display the database data to an jtable(dynamic) in the swings!

    - by harish0510
    we are using hibernate in business layer,but the task is, by using the jtable in swings to display the dynamic data(swings) from the database. code: Criteria criteria=session.createCriteria(User.class); //here user.class is pojo class in hibernate. List studentlist= criteria.list(); System.out.println("records"+studentlist); here the data is showing in hibernate console, but how to represent that data in the format of "jtable".

    Read the article

  • Why do we need a private constructor?

    - by isthatacode
    if a class has a private constructor then it cant be instantiated. so, if i dont want my class to be instantiated and still use it, then i can make it static. what is the use of a private constructor ? Also its used in singleton class, except that, is there any othe use ? (Note : The reason i am excuding the singleton case above is because I dont understand why do we need a singleton at all ? when there is a static class availble. You may not answer for my this confusion in the question. )

    Read the article

  • Is inheritance bad nowadays?

    - by mafutrct
    Personally, I think inheritance is a great tool, that, when applied reasonably, can greatly simplify code. However, I seems to me that many modern tools dislike inheritance. Let's take a simple example: Serialize a class to XML. As soon as inheritance is involved, this can easily turn into a mess. Especially if you're trying to serialize a derived class using the base class serializer. Sure, we can work around that. Something like a KnownType attribute and stuff. Besides being an itch in your code that you have to remember to update every time you add a derived class, that fails, too, if you receive a class from outside your scope that was not known at compile time. (Okay, in some cases you can still work around that, for instance using the NetDataContract serializer in .NET. Surely a certain advancement.) In any case, the basic principle still exists: Serialization and inheritance don't mix well. Considering the huge list of programming strategies that became possible and even common in the past decade, I feel tempted to say that inheritance should be avoided in areas that relate to serialization (in particular remoting and databases). Does that make sense? Or am messing things up? How do you handle inheritance and serialization?

    Read the article

  • Problems with capturing an event in child object in Actionscript

    - by Raigomaru
    I have two classes. The first one (the starting class): package { import flash.display.Sprite; import flash.events.KeyboardEvent; import tetris.*; public class TetrisGame extends Sprite { private var _gameWell:Well; public function TetrisGame() { _gameWell = new Well(); addChild(_gameWell); } } } The second: package tetris { import flash.display.Sprite; import flash.events.KeyboardEvent; public class Well extends Sprite { public function Well() { super(); addEventListener(KeyboardEvent.KEY_DOWN, onKeyboard); } private function onKeyboard():void { //some code is here } } } But when I press any buttons on my keyboard, the child class Well doesn't have any reaction. What's the problem?

    Read the article

  • How to override jquery's show() and hide() functions

    - by Max Williams
    hi all Short version of question: see title Long version of question: I've used jquery's show() and hide() functions extensively in my code and just encountered a bit of a problem: they work by changing the display attribute of the element to 'block' or 'none' respectively, so that if you have somethin that has display: inline and then hide and show it, you've changed its display to block, which screws up the layout in a couple of cases. In my code, whenever i want something to be hidden initially i give it a class 'hidden'. This class is simply {display: none}. I'd like the change show and hide to remove or add this class, instead of directly changing the display attribute, so that if you add the hidden class and then remove it again (ie hide and show something) then it's back to exactly how it was to start off with (since adding a class overrides the attributes rather than directly changing them). Something like this (this is a little pseucodey as i don't know how to set the function up properly - let's assume that 'this' is the object that show/hide was called on) function show(){ this.removeClass("hidden"); } function hide(){ this.addClass("hidden"); } how and where would i go about overriding the jquery methods? (I'm not a javascript expert) thanks - max

    Read the article

  • Trying to change img src if another element is visible with jQuery

    - by R.J.
    I have a div ("panel" class) on my page that toggles open/closed on the click of a paragraph element ("flip" class), which has an image inside of it. Here's the HTML: <div class="panel">Contact info</div> <p class="flip"><img src="images/contactExpand.png" />Expand</p> And the jQuery: $(".flip").click(function(){ $(".panel").slideToggle("slow"); }); Everything works fine so far, but I want the image src to change to "contactCollapse.png" when the panel div is visible. This doesn't seem to do anything (image just stays the same): if ($(".panel").is(":visible") == true) { $(".flip img").attr("src","../images/contactCollapse.png") } else { $(".flip img").attr("src","../images/contactExpand.png") } Am I missing something? Thanks for any help!

    Read the article

  • PHP preg_match image between html tags

    - by Alvins
    I've got an html template like this: <div class="cont"> <div class="..."> <p>...<p> <img alt="" class="popup" src="DESIRED IMAGE LINK" style="..." /></p><p>...</p> .... And i want to extract "DESIRED IMAGE LINK" inside the "" tag, currently i'm using this: $pattern = '<div class="cont">.*?src=["\']?([^"\']?.*?(png|jpg|jpeg|gif))["\']?/i'; if (preg_match($pattern, $content, $image)) ..... But it doesn't work, the error is: warning: preg_match() [function.preg-match]: Unknown modifier '.' How can i fix it? Thanks

    Read the article

  • C++ function for picking from a list where each element has a distinct probability

    - by Stuart
    I have an array of structs and one of the fields in the struct is a float. I want to pick one of the structs where the probability of picking it is relative to the value of the float. ie struct s{ float probability; ... } sArray s[50]; What is the fastest way to decide which s to pick? Is there a function for this? If I knew the sum of all the probability fields (Note it will not be 1), then could I iterate through each s and compare probability/total_probability with a random number, changing the random number for each s? ie if( (float) (rand() / RAND_MAX) < probability)...

    Read the article

  • Finding object count where a field is unique in Django

    - by Johnd
    I have a model that is something like this: class Input(models.Model): details = models.CharField(max_length=1000) user = models.ForeignKey(User) class Case(Input): title = models.CharField(max_length=200) views = models.IntegerField() class Argument(Input): case = models.ForeignKey(Case) side = models.BooleanField() A user can submit many arguments, per case. I want to be able to say how many users have submitted side=true arguments. I mean if 1 user had 10 arguments and another user had 2 arguments (both side=true) I'd want the count to be 2, not 12.

    Read the article

  • How to check if TypeIdenitifier(T) is an Object?

    - by John
    I'm creating a generic list class that has a member of type Array(Array of ). The problem is the class descruction,because the class is supposed to be used for types from byte to types inheriting TObject. Specifically: destructor Destroy; var elem:T; begin /*if(T is Tobject) then //Check if T inherits TObject {Compiler error!} for elem in FData do TObject(elem).Free;*/ // do not know how to do it SetLength(FItems,0); //FItems : Array of T inherited Destroy; end; How do I check if T is TObject so I can free every member if the typeidenitifier is a class,for example?

    Read the article

  • Inferring type from method generics

    - by ng
    I am from a Java background and I am looking from the equivalent in c# for the following. public interface Reader { <T> T read(Class<? extends T> type); } Such that I can do the following, constraining the parameter and inferring the return type. Cat cat = reader.read(Cat.class); Dog dog = reader.read(Dog.class); I was hoping something like this would work in c# but I am not sure it will. public interface Reader { T Read<T>(); } And and do this. public class TypeReader : Reader { public T Read<T>() { Type type = T.GetType(); ... } } Is something like this even possible in c#?

    Read the article

  • Error : The Type Initializer of Daemon.Global threw an exception in c#

    - by srk
    I am using the below class file, where some variables are declared to use in the entire application. Now I used that variable BlockLogOut in another class file to make the value true. I just put this below line and getting error in it.. TypeInitializationException Global.BlockLogOut = True; The weird thing is, it was working fine for many months and i am getting this error now on the above line. Of course i was modifying some other stuffs in the application, but surely not this class file. What would have been the problem? namespace Daemon { class Global { public static bool BlockLogOut = false; } }

    Read the article

  • Integration testing - can it be done right?

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

    Read the article

  • ZF2 namespace and file system

    - by user1918648
    I have standard Application module in ZF2. It's configured by default, I didn't change anything. I just added some stuff: module/ Application/ src/ Application/ Entity/ Product/ **Product.php** Controller/ **IndexController.php** Product.php namespace Application\Entity; class Product { } IndexController.php namespace Application\Controller; use Zend\Mvc\Controller\AbstractActionController; use Zend\View\Model\ViewModel; use Application\Entity\Product; class IndexController extends AbstractActionController { public function indexAction() { $product = new Product(); } } and I get following error: Fatal error: Class 'Application\Entity\Product' not found in \module\Application\src\Application\Controller\IndexController.php on line 20 I use the same namespace, but it doesn't see it. Why? P.S: If I will change Product.php to be the following: namespace Application\Entity\Product; class Product { } then in the IndexController.php the following code will be working: namespace Application\Controller; use Zend\Mvc\Controller\AbstractActionController; use Zend\View\Model\ViewModel; use Application\Entity\Product\Product; class IndexController extends AbstractActionController { public function indexAction() { $product = new Product(); } }

    Read the article

  • How can I use the HTML5 <button> tag in Drupal 6

    - by Frankie Yale
    I have the following HTML which I'd like to use in my Drupal 6 theme. It needs to replace the search-box code. <fieldset class="search"> <input type="text" class="box font-myriad" /> <button class="btn" title="Submit Search">Search</button> </fieldset> I'm trying stuff like $vars['form']['button']['#attributes'] = array('class' => 'btn'); in template.php, but no luck so far. Couldn't find much help on drupal.org.

    Read the article

< Previous Page | 629 630 631 632 633 634 635 636 637 638 639 640  | Next Page >