Search Results

Search found 11360 results on 455 pages for 'helper classes'.

Page 290/455 | < Previous Page | 286 287 288 289 290 291 292 293 294 295 296 297  | Next Page >

  • Weird generics compile error.

    - by Jouke van der Maas
    I have two classes, a base class and a child class. In the base class i define a generic virtual method: protected virtual Bar Foo<T() where T : Bar {} Then in my child class i try to do this: protected override BarChild Foo() // BarChild inherits Bar { return base.Bar<T as BarChild() } Visual studio gives this weird error: The type 'T' cannot be used as type parameter 'T' in the generic type or method 'Foo()'. There is no boxing conversion or type parameter conversion from 'T' to 'Bar'. Repeating the where clause on the child's override also gives an error: Constraints for override and explicit interface implementation methods are inherited from the base method, so they cannot be specified directly So what am i doing wrong here?

    Read the article

  • How to create a container that holds different types of function pointers in C++?

    - by Alex
    I'm doing a linear genetic programming project, where programs are bred and evolved by means of natural evolution mechanisms. Their "DNA" is basically a container (I've used arrays and vectors successfully) which contain function pointers to a set of functions available. Now, for simple problems, such as mathematical problems, I could use one type-defined function pointer which could point to functions that all return a double and all take as parameters two doubles. Unfortunately this is not very practical. I need to be able to have a container which can have different sorts of function pointers, say a function pointer to a function which takes no arguments, or a function which takes one argument, or a function which returns something, etc (you get the idea)... Is there any way to do this using any kind of container ? Could I do that using a container which contains polymorphic classes, which in their turn have various kinds of function pointers? I hope someone can direct me towards a solution because redesigning everything I've done so far is going to be painful.

    Read the article

  • How to Add a File from my source tree to Maven Site

    - by Charles O.
    I have a Maven 2 RESTful application using Jersey/JAXB. I generate the JAXB beans from a schema file, where the schema file is in my resources directory, e.g., src/main/resources/foo.xsd. I want to include foo.xsd file in the generated Maven site for my project, so that clients can see the XML schema when writing RESTful calls. How can I include foo.xsd in the site? I could have a copy of the file in src/main/site/..., and then update my site.xml to point to it (or have a .apt whose contents point to it), but I don't like that because I'm still tweaking foo.xsd, and don't want to have to remember to copy it each time I update it. And that's just bad practice. I also tried having a .apt file that has a link to the foo.xsd which gets copied to the target/classes directory. That works until I do a site:deploy, because that only copies the target/site directory. Thanks, Charles

    Read the article

  • MyClass cannot be cast to java.lang.Comparable: java.lang.ClassCastException

    - by user2234225
    I am doing a java project and I got this problem and don't know how to fix it. The classes in my project (simplified): public class Item { private String itemID; private Integer price; public Integer getPrice() { return this.price; } } public class Store { private String storeID; private String address; } public class Stock { private Item item; private Store store; private Integer itemCount; public Integer getInventoryValue() { return this.item.getPrice() * this.itemCount; } } Then I try to sort an ArrayList of Stock so I create another class called CompareByValue public class CompareByValue implements Comparator<Stock> { @Override public int compare(Stock stock1, Stock stock2) { return (stock1.getInventoryValue() - stock2.getInventoryValue()); } } When I try to run the program, it gives the error: Exception in thread "main" java.lang.ClassCastException: Stock cannot be cast to java.lang.Comparable Anyone know what's wrong?

    Read the article

  • Debug Mode for CodeIgniter?

    - by nebukadnezzar
    Does CodeIgniter provide a Debug Mode, for example, when accessing an Invalid URL? Ruby on Rails does show debugging Messages when a incorrect URL has been given, and the controller is unable to resolve it using the routes map. How would I enable such debugging messages in CodeIgniter? The profiler ... $this->output->enable_profiler(TRUE); ... only affects single classes, but not all routes. So debugging without an actual debugger mode is a little... difficult. :-)

    Read the article

  • Overly accessible and incredibly resource hungry relationships between business objects. How can I f

    - by Mike
    Hi, Firstly, This might seem like a long question. I don't think it is... The code is just an overview of what im currently doing. It doesn't feel right, so I am looking for constructive criticism and warnings for pitfalls and suggestions of what I can do. I have a database with business objects. I need to access properties of parent objects. I need to maintain some sort of state through business objects. If you look at the classes, I don't think that the access modifiers are right. I don't think its structured very well. Most of the relationships are modelled with public properties. SubAccount.Account.User.ID <-- all of those are public.. Is there a better way to model a relationship between classes than this so its not so "public"? The other part of this question is about resources: If I was to make a User.GetUserList() function that returns a List, and I had 9000 users, when I call the GetUsers method, it will make 9000 User objects and inside that it will make 9000 new AccountCollection objects. What can I do to make this project not so resource hungry? Please find the code below and rip it to shreds. public class User { public string ID {get;set;} public string FirstName {get; set;} public string LastName {get; set;} public string PhoneNo {get; set;} public AccountCollection accounts {get; set;} public User { accounts = new AccountCollection(this); } public static List<Users> GetUsers() { return Data.GetUsers(); } } public AccountCollection : IEnumerable<Account> { private User user; public AccountCollection(User user) { this.user = user; } public IEnumerable<Account> GetEnumerator() { return Data.GetAccounts(user); } } public class Account { public User User {get; set;} //This is public so that the subaccount can access its Account's User's ID public int ID; public string Name; public Account(User user) { this.user = user; } } public SubAccountCollection : IEnumerable<SubAccount> { public Account account {get; set;} public SubAccountCollection(Account account) { this.account = account; } public IEnumerable<SubAccount> GetEnumerator() { return Data.GetSubAccounts(account); } } public class SubAccount { public Account account {get; set;} //this is public so that my Data class can access the account, to get the account's user's ID. public SubAccount(Account account) { this.account = account; } public Report GenerateReport() { Data.GetReport(this); } } public static class Data { public static List<Account> GetSubAccounts(Account account) { using (var dc = new databaseDataContext()) { List<SubAccount> query = (from a in dc.Accounts where a.UserID == account.User.ID //this is getting the account's user's ID select new SubAccount(account) { ID = a.ID, Name = a.Name, }).ToList(); } } public static List<Account> GetAccounts(User user) { using (var dc = new databaseDataContext()) { List<Account> query = (from a in dc.Accounts where a.UserID == User.ID //this is getting the user's ID select new Account(user) { ID = a.ID, Name = a.Name, }).ToList(); } } public static Report GetReport(SubAccount subAccount) { Report report = new Report(); //database access code here //need to get the user id of the subaccount's account for data querying. //i've got the subaccount, but how should i get the user id. //i would imagine something like this: int accountID = subAccount.Account.User.ID; //but this would require the subaccount's Account property to be public. //i do not want this to be accessible from my other project (UI). //reading up on internal seems to do the trick, but within my code it still feels //public. I could restrict the property to read, and only private set. return report; } public static List<User> GetUsers() { using (var dc = new databaseDataContext()) { var query = (from u in dc.Users select new User { ID = u.ID, FirstName = u.FirstName, LastName = u.LastName, PhoneNo = u.PhoneNo }).ToList(); return query; } } }

    Read the article

  • Oddities when mixing Zend Framework 1.11 & Doctrine 2 Autoloaders

    - by jiewmeng
    I have setup autoloading in my ZF/Doctrine2 app as follows $zendAutoloader = Zend_Loader_Autoloader::getInstance(); $autoloader = array(new ClassLoader('Symfony'), 'loadClass'); $zendAutoloader->pushAutoloader($autoloader, 'Symfony'); $autoloader = array(new ClassLoader('Doctrine'), 'loadClass'); $zendAutoloader->pushAutoloader($autoloader, 'Doctrine'); $autoloader = array(new ClassLoader('Application', realpath(__DIR__ . '/..')), 'loadClass'); $zendAutoloader->pushAutoloader($autoloader, 'Application'); $autoloader = array(new ClassLoader('DoctrineExtensions'), 'loadClass'); $zendAutoloader->pushAutoloader($autoloader, 'DoctrineExtensions'); I find that the DoctrineExtensions autoloading is not working while other classes are ... to verify that the path etc are right, I tried $autoloader = new ClassLoader('DoctrineExtensions'); $autoloader->register(); And it works. So it seems it has something to do with Zend Framework?

    Read the article

  • Using OpenGL drawing operations in an object-oriented setting?

    - by Lion Kabob
    I've been plowing through basic shaders and whatnot for an application I'm writing, and I've been having trouble figuring out a high-level organization for the drawing calls. I'm thinking of having a singleton class which implements a number of basic drawing operations, taking data from "user" classes and passing that to the appropriate opengl calls. I'm wondering how people do this when writing their own applications, as the internet is chock full of basic "Your first shader" tutorials, but very little on suggested organization of drawing code. My particular environment is targeted at iPad/OpenGL ES 2.0, but I think the question stands for most environments.

    Read the article

  • Flex Error #1014: Class flash.net::NetStreamPlayOptions

    - by evilpenguin
    I have a pure ActionScript project. I'm using Flex Builder on a Mac, Flex SDK 3.4 and I've even added the playerglobal.swc from the Flash folder to the project's library path. I get autocomplete when I add import flash.net.NetStreamPlayOptions; import flash.net.NetStreamPlayTransitions; But when I run the movie, I get: VerifyError: Error #1014: Class flash.net::NetStreamPlayOptions could not be found. I don't get it.. What must I do to use those classes?

    Read the article

  • Casting Error with Reflection

    - by Mitchel Sellers
    I have an application that uses plugins that are managed via an interface I then dynamically load the plugin classes and cast them to the interface to work with them. I have the following line of code, assume that IPlugin is my interface. IPlugin _plugin = (IPlugin)Activator.CreateInstance(oInfo.Assembly, oInfo.FullyQualifiedName) This should be pretty simple, create the instance and cast it to the interface. I know that the assembly and fully qualified name values are correct, but I am getting the following exception. Exception= System.InvalidCastException: Unable to cast object of type ‘System.Runtime.Remoting.ObjectHandle’ to type ‘MyNamespace.Components.Integration.IPlugin’. at MyNamespace.Components.Integration.PluginProxy..ctor(Int32 instanceId) Any ideas what could cause this?

    Read the article

  • Embedding .net remoting program in WEB

    - by flufferok
    So, here is a deal. I have client-server application(dotNet remoting). Client side has few trackbars, checkboxes, buttons and picturebox. Server is a console application and does only calculation from client. Client's picturebox make some visualisation of calculation in picturebox. All calulations and relative classes are in dll file. Now I have to embed client application in web site. All kind of technologies are accepted, but I want to minimize forces applied to embedding. So, what is the best way to do embedding?

    Read the article

  • Visual Studio: Design a UserControl class that derives from an abstract base class

    - by Marcel
    Hi All, I want to have an abstract base class for some of my custom UserControl's. The reason is obvious: they share some common properties and methods (a basic implementation of some elements of an interface actually), and I want to implement them only once. I have done this by defining my abstract base class: public abstract class ViewBase : UserControl, ISomeInterface Then I went to implement one of my views, as usual, with the designer: public partial class SpecialView : UserControl //all OK Up to here all is fine. Now I replace the derivation of my SpecialView class with the abstract base class: public partial class SpecialView : ViewBase //disrupts the designer Now, the designer in Visual Studio 2008 won't work anymore, stating: The designer must create an instance of type 'ViewBase' but it cannot because the type is declared as abstract. How can I circumvent this? I just do not want to have the same code copied for all those views. Info: there is a question question with virtual methods, instead of abstract classes, but there is no suitable solution for me.

    Read the article

  • Python: Can subclasses overload inherited methods?

    - by Rosarch
    I'm making a shopping cart app in Google App Engine. I have many classes that derive from a base handler: class BaseHandler(webapp.RequestHandler): def get(self, CSIN=None): self.body(CSIN) Does this mean that the body() method of every descendant class needs to have the same argument? This is cumbersome. Only one descendant actually uses that argument. And what about when I add new args? Do I need to go through and change every class? class Detail(BaseHandler): def body(self, CSIN): class MainPage(BaseHandler): def body(self, CSIN=None): #@UnusedVariable class Cart(BaseHandler): def body(self, CSIN): #@UnusedVariable

    Read the article

  • linq to sql datacontext for a web application

    - by rap-uvic
    Hello, I'm trying to use linq to sql for my project (very short deadline), and I'm kind of in a bind. I don't know the best way to have a data context handy per request thread. I want something like a singleton class from which all my repository classes can access the current data context. However, singleton class is static and is not thread-safe and therefore not suitable for web apps. I want something that would create a data context at the beginning of the request and dispose of it along with the request. Can anyone please share their solution to this problem? I've been searching for a solution and I've found a good post from Rick Strahl : http://www.west-wind.com/weblog/posts/246222.aspx but I don't completely understand his thread-safe or business object approach. If somebody has a simplified version of his thread-safe approach, i'd love to take a look.

    Read the article

  • maven: multi-module project assembly into single jar

    - by Jeroen
    I have a multi-module project and want to create a single jar containing the classes of all my modules. Inside my parent POM, I declared the following plugin: <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-assembly-plugin</artifactId> <configuration> <descriptorRefs> <descriptorRef>bin</descriptorRef> </descriptorRefs> </configuration> </plugin> However, when running mvn assembly:assembly, only the source from the parent folder (empty) are included. How do I include the sources from my modules into the archive?

    Read the article

  • Netbeans GUI editor generating its own incomprehensible code.

    - by WarDoGG
    When creating a new project in netbeans, if i select JAVA Desktop application, it creates some code which I DO NOT RECOGNISE AT ALL as what i had learnt in swing. It imports packages such as : org.jdesktop.application.SingleFrameApplication; also, the declaration for main() looks like this : public static void main(String[] args) { launch(DesktopApplication2.class, args); } This really does not make any sense to my knowledge of JFrame, JPanel etc.. If i try to code a netbeans application from scratch, i can write my own swing app BUT I CANNOT FIND THE GUI EDITOR. How do i bring the GUI editor when creating java application from scratch ? Can anyone explain to me this org.jdesktop.application.SingleFrameApplication and other classes ? Please help. This is really frustrating.

    Read the article

  • optional local variables in rails partial templates: how do I get out of the (defined? foo) mess?

    - by brahn
    I've been a bad kid and used the following syntax in my partial templates to set default values for local variables if a value wasn't explicitly defined in the :locals hash when rendering the partial -- <% foo = default_value unless (defined? foo) %> This seemed to work fine until recently, when (for no reason I could discern) non-passed variables started behaving as if they had been defined to nil (rather than undefined). As has been pointed by various helpful people on SO, http://api.rubyonrails.org/classes/ActionView/Base.html says not to use defined? foo and instead to use local_assigns.has_key? :foo I'm trying to amend my ways, but that means changing a lot of templates. Can/should I just charge ahead and make this change in all the templates? Is there any trickiness I need to watch for? How diligently do I need to test each one?

    Read the article

  • Castle Windsor - Resolving a generic implementation to a base type

    - by arootbeer
    I'm trying to use Windsor as a factory to provide specification implementations based on subtypes of XAbstractBase (an abstract message base class in my case). I have code like the following: public abstract class XAbstractBase { } public class YImplementation : XAbstractBase { } public class ZImplementation : XAbstractBase { } public interface ISpecification<T> where T : XAbstractBase { bool PredicateLogic(); } public class DefaultSpecificationImplementation : ISpecification<XAbstractBase> { public bool PredicateLogic() { return true; } } public class SpecificSpecificationImplementation : ISpecification<YImplementation> { public bool PredicateLogic() { /*do real work*/ } } My component registration code looks like this: container.Register( AllTypes.FromAssembly(Assembly.GetExecutingAssembly()) .BasedOn(typeof(ISpecification<>)) .WithService.FirstInterface() ) This works fine when I try to resolve ISpecification<YImplementation>; it correctly resolves SpecificSpecificationImplementation. However, when I try to resolve ISpecification<ZImplementation> Windsor throws an exception: "No component for supporting the service ISpecification'1[ZImplementation, AssemblyInfo...] was found" Does Windsor support resolving generic implementations down to base classes if no more specific implementation is registered?

    Read the article

  • Django admin.py missing field error

    - by user782400
    When I include 'caption', I get an error saying EntryAdmin.fieldsets[1][1]['fields']' refers to field 'caption' that is missing from the form In the admin.py; I have imported the classes from joe.models import Entry,Image Is that because my class from models.py is not getting imported properly ? Need help in resolving this issue. Thanks. models.py class Image(models.Model): image = models.ImageField(upload_to='joe') caption = models.CharField(max_length=200) imageSrc = models.URLField(max_length=200) user = models.CharField(max_length=20) class Entry(models.Model): image = models.ForeignKey(Image) mimeType = models.CharField(max_length=20) name = models.CharField(max_length=200) password = models.URLField(max_length=50) admin.py class EntryAdmin(admin.ModelAdmin): fieldsets = [ ('File info', {'fields': ['name','password']}), ('Upload image', {'fields': ['image','caption']})] list_display = ('name', 'mimeType', 'password') admin.site.register(Entry, EntryAdmin) admin.site.register(Image)

    Read the article

  • Handling inverted pixels in bitmapData and bitmap class in as3

    - by intoTHEwild
    I am using bitmapData and bitmap classes to render a mouse cursor on the display screen. The bitmapData consists of an area whose colors should be inverted according to the background color. This is a very basic thing which could be observed with text cursor(the vertical line with two small horizontals on top and bottom), when moved over the text area. I want to be able to do the same with the pixels in my bitmapData, is there a way to find out the background color effectively and invert the color values? In this process i will be redrawing the whole pixels, is there any other efficient way to do that ?

    Read the article

  • Better type safety in Java collections

    - by Paul Tomblin
    In my java coding, I often end up with several Map<String,Map<String,foo>> or Map<String,List<String>> and then I have trouble remembering which String is which key. I comment the declaration with //Map<capabiltyId,Map<groupId,foo>> or //Map<groupId,List<capabilityId>, but it's not the greatest solution. If String wasn't final, I would make new classes CapabilityId extends String and GroupId extends String, but I can't. Is there a better way to keep track of which thing is the key and maybe have the compiler enforce it?

    Read the article

  • What's the difference between IEquatable and just overriding Object.Equals() ?

    - by devoured elysium
    I want my Food class to be able to test whenever it is equal to another class. I will later use it against a List, and I want to use its List.Contains() method. Should I implement IEquatable or just override Object.Equals()? From MSDN: This method determines equality by using the default equality comparer, as defined by the object's implementation of the IEquatable.Equals method for T (the type of values in the list). So my next question is: which functions/classes of the .NET framework make use of Object.Equals()? Should I use it in the first place? Thanks

    Read the article

  • iPHone: Unit/Logic Tests initWithNibName

    - by pion
    I have setup my Logic Tests following the instructions on http://developer.apple.com/iphone/library/documentation/Xcode/Conceptual/iphone_development/135-Unit_Testing_Applications/unit_testing_applications.html. I could test a couple classes successfully. But I got error when testing the following: - (id)init { if (self = [super initWithNibName:@"Foo" bundle:nil]) { ... } return self; } The error message is -[UIViewController _loadViewFromNibNamed:bundle:] was unable to load a nib named "Foo" My question: Did I do something wrong? Missed something? or I cannot test -initWithNibName using Logic Tests technique. Thanks in advance for your help.

    Read the article

  • How do I Call a method from other Class

    - by balexandre
    Hi guys, I'm having some trouble figuring out to call methods that I have in other classes #import "myNewClass.h" #import "MainViewController.h" @implementation MainViewController @synthesize txtUsername; @synthesize txtPassword; @synthesize lblUserMessage; - (IBAction)calculateSecret { NSString *usec = [self calculateSecretForUser:txtUsername.text withPassword:txtPassword.text]; [lblUserMessage setText:usec]; [usec release]; } ... myNewClass.h #import <Foundation/Foundation.h> @interface myNewClass : NSObject { } - (NSString*)CalculateSecretForUser:(NSString *)user withPassword:(NSString *)pwd; @end myNewClass.m #import "myNewClass.h" @implementation myNewClass - (NSString*)CalculateSecretForUser:(NSString *)user withPassword:(NSString *)pwd { NSString *a = [[NSString alloc] initWithFormat:@"%@ -> %@", user, pwd]; return a; } @end the method CalculateSecretForUser always says 'MainViewController' may not respond to '-calculateSecretForUser:withPassword:' what am I doing wrong here?

    Read the article

  • linq to sql dynamic data modify object before insert and update

    - by Dan Tanner
    I'm using Dynamic Data and LINQ to SQL for some admin pages on a .NET 3.5 web app. All my admin tables a CreatedBy, CreatedDate, UpdatedBy, and UpdatedDate. I'm looking for a way to inject the setting of these properties before the objects are inserted and updated. I've seen an object_inserting hook if you have a linq to sql datasource in the web form, but I'm using dynamic data...is there an easy way to generically set that? And I've also looked at modifying each of the partial classes for my admin objects, but the closest hook I see is to implement the OnValidate method with the Insert action. Any suggestions? TIA.

    Read the article

< Previous Page | 286 287 288 289 290 291 292 293 294 295 296 297  | Next Page >