Search Results

Search found 2051 results on 83 pages for 'abstract'.

Page 64/83 | < Previous Page | 60 61 62 63 64 65 66 67 68 69 70 71  | Next Page >

• Can the Diamond Problem be really solved?

  - by Mecki

  A typical problem in OO programming is the diamond problem. I have parent class A with two sub-classes B and C. A has an abstract method, B and C implement it. Now I have a sub-class D, that inherits of B and C. The diamond problem is now, what implementation shall D use, the one of B or the one of C? People claim Java knows no diamond problem. I can only have multiple inheritance with interfaces and since they have no implementation, I have no diamond problem. Is this really true? I don't think so. See below: [removed vehicle example] Is a diamond problem always the cause of bad class design and something neither programmer nor compiler needs to solve, because it shouldn't exist in the first place? Update: Maybe my example was poorly chosen. See this image Of course you can make Person virtual in C++ and thus you will only have one instance of person in memory, but the real problem persists IMHO. How would you implement getDepartment() for GradTeachingFellow? Consider, he might be student in one department and teach in another one. So you can either return one department or the other one; there is no perfect solution to the problem and the fact that no implementation might be inherited (e.g. Student and Teacher could both be interfaces) doesn't seem to solve the problem to me.

  Read the article

• FileNotFoundException, although the XML file should be deployed

  - by Bernhard V

  Hi, I've got problems starting my WAR application on a local JBoss. After two other EARs are deployed and the TomcatDeployer begins deploying the WAR, I'm getting the following error message: 2010-04-28 10:01:56,605 ERROR [org.jboss.ejb.plugins.LogInterceptor] [] [main] EJBException in method: public abstract at.sozvers.stp.zpv.ejb.lea.rwsuc.EJBLeaRegelwerkSuchenRemote at.sozvers.stp.zpv.ejb.lea.rwsuc.EJBLeaRegelwerkSuchenHome.create() throws javax.ejb.CreateException,java.rmi.RemoteException, causedBy: javax.ejb.EJBException: org.springframework.beans.factory.access.BootstrapException: Unable to initialize group definition. Group resource name [classpath*:applicationContext.xml], factory key [contextService]; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'contextService' defined in URL [jar:file:/C:/ta30/nutzb/jboss-4.2.3.GA.ZPV/server/default/deploy/deploy.last/zpv-app-web-frontend-1.0-SNAPSHOT.war/WEB-INF/lib/zpv-comp-ejb-modules-1.0-SNAPSHOT-client.jar!/applicationContext.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.context.support.ClassPathXmlApplicationContext]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [at/sozvers/stp/zpv/dao/ContextBasic.xml]; nested exception is java.io.FileNotFoundException: class path resource [at/sozvers/stp/zpv/dao/ContextBasic.xml] cannot be opened because it does not exist The sad thing is that the resource at/sozvers/stp/zpv/dao/ContextBasic.xml actually is placed in a JAR in one of my EAR files which should be deployed before the WAR. And at least I get a message that the deployment of the EAR has been successful. I also looked into the JAR with my file archiver and the ContextBasic.xml is indeed there at the right place. Is there a way for me to get sure that the JAR, not the EAR as a whole, is really deployed to the JBoss? I'm already starting to lose my head about this issue. Thank you. Bernhard

  Read the article

• How to use a Spring config file in a Maven dependency

  - by javamonkey79

  In dependency A I have the following: <beans> <bean id="simplePersonBase" class="com.paml.test.SimplePerson" abstract="true"> <property name="firstName" value="Joe" /> <property name="lastName" value="Smith" /> </bean> </beans> And then in project B, I add A as a dependency and have the following config: <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="simplePersonAddress01" parent="simplePersonBase"> <property name="firstName" value="BillyBob" /> <property name="address" value="1060 W. Addison St" /> <property name="city" value="Chicago" /> <property name="state" value="IL" /> <property name="zip" value="60613" /> </bean> </beans> When I use ClassPathXmlApplicationContext like so: BeanFactory beanFactory = new ClassPathXmlApplicationContext( new String[] { "./*.xml" } ); SimplePerson person = (SimplePerson)beanFactory.getBean( "simplePersonAddress01" ); System.out.println( person.getFirstName() ); Spring complains as it can not resolve the parent xml. Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'simplePersonBase' is defined I am sure there is a way to do this, however, I have not found it. Does anyone know how?

  Read the article

• Setting database-agnostic default column timestamp using Hibernate

  - by unsquared

  I'm working on a java project full of Hibernate (3.3.1) mapping files that have the following sort of declaration for most domain objects. <property name="dateCreated" generated="insert"> <column name="date_created" default="getdate()" /> </property> The problem here is that getdate() is an MSSQL specific function, and when I'm using something like H2 to test subsections of the project, H2 screams that getdate() isn't a recognized function. It's own timestamping function is current_timestamp(). I'd like to be able to keep working with H2 for testing, and wanted to know whether there was a way of telling Hibernate "use this database's own mechanism for retrieving the current timestamp". With H2, I've come up with the following solution. CREATE ALIAS getdate AS $$ java.util.Date now() { return new java.util.Date(); } $$; CALL getdate(); It works, but is obviously H2 specific. I've tried extending H2Dialect and registering the function getdate(), but that doesn't seem to be invoked when Hibernate is creating tables. Is it possible to abstract the idea of a default timestamp away from the specific database engine?

  Read the article

• How to not pass around the container when using IoC in Winforms

  - by L2Type

  I'm new to the world of IoC and having a problem with implementing it in a Winforms application. I have an extremely basic application Winform application that uses MVC, it is one controller that does all the work and a working dialog (obviously with a controller). So I load all my classes in to my IoC container in program.cs and create the main form controller using the container. But this is where I am having problems, I only want to create the working dialog controller when it's used and inside a using statement. At first I passed in the container but I've read this is bad practice and more over the container is a static and I want to unit test this class. So how do you create classes in a unit test friendly way without passing in the container, I was considering the abstract factory pattern but that alone would solve my problem without using the IoC. I'm not using any famous framework, I borrowed a basic one from this blog post http://www.kenegozi.com/Blog/2008/01/17/its-my-turn-to-build-an-ioc-container-in-15-minutes-and-33-lines.aspx How do I do this with IoC? Is this the wrong use for IoC?

  Read the article

• How to mock the Request.ServerVariables using MOQ for ASP.NET MVC?

  - by melaos

  hi guys, i'm just learning to put in unit testing for my asp.net mvc when i came to learn about the mock and the different frameworks there is out there now. after checking SO, i found that MOQ seems to be the easiest to pick up. as of now i'm stuck trying to mock the Request.ServerVariables, as after reading this post, i've learned that it's better to abstract them into property. as such: /// <summary> /// Return the server port /// </summary> protected string ServerPort { get { return Request.ServerVariables.Get("SERVER_PORT"); } } But i'm having a hard time learning how to properly mock this. I have a home controller ActionResult function which grabs the user server information and proceed to create a form to grab the user's information. i tried to use hanselman's mvcmockhelpers class but i'm not sure how to use it. this is what i have so far... [Test] public void Create_Redirects_To_ProductAdded_On_Success() { FakeViewEngine engine = new FakeViewEngine(); HomeController controller = new HomeController(); controller.ViewEngine = engine; MvcMockHelpers.SetFakeControllerContext(controller); controller.Create(); var results = controller.Create(); var typedResults = results as RedirectToRouteResult; Assert.AreEqual("", typedResults.RouteValues["action"], "Wrong action"); Assert.AreEqual("", typedResults.RouteValues["controller"], "Wrong controller"); } Questions: As of now i'm still getting null exception error when i'm running the test. So what am i missing here? And if i use the mvcmockhelpers class, how can i still call the request.verifyall function to ensure all the mocking are properly setup?

  Read the article

• Asp net aspx page and webcontrol issue

  - by Josemalive

  Hello, I have a class that inherits from Page, called APage. public abstract class APage: Page { protected Repeater ExampleRepeater; .... protected override void OnLoad(EventArgs e) { if (null != ExampleRepeater) { ExampleRepeater.DataSource = GetData(); ExampleRepeater.DataBind(); } base.OnLoad(e); } } For other hand i have an aspx page called Default that inherits from this APage: public partial class Default : APage { } on the design part of this Default page, i have a repeater: <asp:Repeater ID="ExampleRepeater" runat="server"> <ItemTemplate> <%# DataBinder.Eval(Container.DataItem, "Name") %><br/> </ItemTemplate> </asp:Repeater> This repeater is datasourced at the base APage load event, but at this level this web control is null. Do you have any idea why the control is null in the base page? Thanks in advance. Best Regards. Jose.

  Read the article

• Hibernate triggering constraint violations using orphanRemoval

  - by ptomli

  I'm having trouble with a JPA/Hibernate (3.5.3) setup, where I have an entity, an "Account" class, which has a list of child entities, "Contact" instances. I'm trying to be able to add/remove instances of Contact into a List<Contact> property of Account. Adding a new instance into the set and calling saveOrUpdate(account) persists everything lovely. If I then choose to remove the contact from the list and again call saveOrUpdate, the SQL Hibernate seems to produce involves setting the account_id column to null, which violates a database constraint. What am I doing wrong? The code below is clearly a simplified abstract but I think it covers the problem as I'm seeing the same results in different code, which really is about this simple. SQL: CREATE TABLE account ( INT account_id ); CREATE TABLE contact ( INT contact_id, INT account_id REFERENCES account (account_id) ); Java: @Entity class Account { @Id @Column public Long id; @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true) @JoinColumn(name = "account_id") public List<Contact> contacts; } @Entity class Contact { @Id @Column public Long id; @ManyToOne(optional = false) @JoinColumn(name = "account_id", nullable = false) public Account account; } Account account = new Account(); Contact contact = new Contact(); account.contacts.add(contact); saveOrUpdate(account); // some time later, like another servlet request.... account.contacts.remove(contact); saveOrUpdate(account); Result: UPDATE contact SET account_id = null WHERE contact_id = ? Edit #1: It might be that this is actually a bug http://opensource.atlassian.com/projects/hibernate/browse/HHH-5091

  Read the article

• Need some help/advice on WCF Per-Call Service and NServiceBus interop.

  - by Alexey

  I have WCF Per-Call service wich provides data for clients and at the same time is integrated with NServiceBus. All statefull objects are stored in UnityContainer wich is integrated into custom service host. NServiceBus is configured in service host and uses same container as service instances. Every client has its own instance context(described by Juval Lowy in his book in chapter about Durable Services). If i need to send request over bus I just use some kind of dispatcher and wait response using Thread.Sleep().Since services are per-call this is ok afaik. But I am confused a bit about messages from bus, that service must handle and provide them to clients. For some data like stock quotes I just update some kind of statefull object and and then, when clients invoke GetQuotesData() just provide data from this object. But there are numerous service messages like new quote added and etc. At this moment I have an idea to implement something like "Postman daemon" =)) and store this type of messages in instance context. Then client will invoke "GetMail()",recieve those messages and parse them. Problem is that NServiceBus messages are "Interface based" and I cant pass them over WCF, so I need to convert them to types derieved from some abstract class. Dunno what is best way to handle this situation. Will be very gratefull for any advice on this. Thanks in advance.

  Read the article

• Sweave/R - Automatically generating an appendix that contains all the model summaries/plots/data pro

  - by John Horton

  I like the idea of making research available at multiple levels of detail i.e., abstract for the casually curious, full text for the more interested, and finally the data and code for those working in the same area/trying to reproduce your results. In between the actual text and the data/code level, I'd like to insert another layer. Namely, I'd like to create a kind of automatically generated appendix that contains the full regression output, diagnostic plots, exploratory graphs data profiles etc. from the analysis, regardless of whether those plots/regressions etc. made it into the final paper. One idea I had was to write a script that would examine the .Rnw file and automatically: Profile all data sets that are loaded (sort of like the Hmisc(?) package) Summarize all regressions - i.e., run summary(model) for all models Present all plots (regardless of whether they made it in the final version) The idea is to make this kind of a low-effort, push-button sort of thing as opposed to a formal appendix written like the rest of a paper. What I'm looking for is some ideas on how to do this in R in a relatively simple way. My hunch is that there is some way of going through the namespace, figuring out what something is and then dumping into a PDF. Thoughts? Does something like this already exist?

  Read the article

• Design considerations for temporarily transforming a player into an animal in a role playing game

  - by mikedev

  I am working on a role playing game for fun and to practice design patterns. I would like players to be able to transform themselves into different animals. For example, a Druid might be able to shape shift into a cheetah. Right now I'm planning on using the decorator pattern to do this but my question is - how do I make it so that when a druid is in the cheetah form, they can only access skills for the cheetah? In other words, they should not be able to access their normal Druid skills. Using the decorator pattern it appears that even in the cheetah form my druid will be able to access their normal druid skills. class Druid : Character { // many cool druid skills and spells void LightHeal(Character target) { } } abstract class CharacterDecorator : Character { Character DecoratedCharacter; } class CheetahForm : CharacterDecorator { Character DecoratedCharacter; public CheetahForm(Character decoratedCharacter) { DecoratedCharacter= decoratedCharacter; } // many cool cheetah related skills void CheetahRun() { // let player move very fast } } now using the classes Druid myDruid = new Druid(); myDruid.LightHeal(myDruid); // casting light heal here is fine myDruid = new CheetahForm(myDruid); myDruid.LightHeal(myDruid); // casting here should not be allowed Hmmmm...now that I think about it, will myDruid be unable to us the Druid class spells/skills unless the class is down-casted? But even if that's the case, is there a better way to ensure that myDruid at this point is locked out from all Druid related spells/skills until it is cast back to a Druid (since currently it's in CheetahForm)

  Read the article

• using Autofac in a multi-layered architecture

  - by Kamyar

  I'm fairly new to the DI/IoC concept and would like to use Autofac in a 3-layered ASP.NET Webforms application. UI layer: An ASP.NET webforms website. BLL: Business logic layer which calls the repositories on DAL. DAL: .EDMX file (Entity Model) and ObjectContext with Repository classes which abstract the CRUD operations for each entity. Entities: The POCO Entities. Persistence Ignorant. Generated by Microsoft's ADO.Net POCO Entity Generator. I have asked a more general question here. Basically, I'd like to create an obejctcontext per HttpContext in my DAL. But i don't want to add a reference to DAL in UI or access to HttpContext in DAL directly. I guess this is where IoC tools come to play. The answer to my previous question is a very good example of using Windsor Castle. I'd like to use Autofac as my IoC tool and Don't know how to achieve this. (How to access DAL in application_start to register the component while I don't want to reference it in my UI, what are the proper references to be able to use DAL component in BLL with Autofac, Should I register BLL as a component with Autofac too) Sorry folks for not providing an explicit question and requesting a kind of working example, But I'm very unfamiliar to the whole IoC concept and I don't think I can achieve it to use in my current time-limited project.

  Read the article

• Is there a way to pass another parameter in the preg_replace_callback callback function?

  - by DaNieL

  mmmh guys, i really hope my english is good enaught to explain what i need. Lets take this example (that is just an example!) of code: class Something(){ public function Lower($string){ return strtolower($string); } } class Foo{ public $something; public $reg; public $string; public function __construct($reg, $string, $something){ $this->something = $something; $this->reg = $reg; $this->string = $string; } public function Replace(){ return preg_replace_callback($this->reg, 'Foo::Bar', $this->string); } public static function Bar($matches){ /* * [...] * do something with $matches and create the $output variable * [...] */ /* * I know is really useless in this example, but i need to have an istance to an object here * (in this example, the Something object, but can be something else!) */ return $this->something->Lower($output); } } $s = new Something(); $foo = new Foo($myregexp, $mystring, $s); $content = $foo->Replace(); So, the php manual say that to use a class method as callback in preg_replace_callback(), the method must be abstract. I need to pass an instance of a previuosly initialized object (in the example, an instance of the Something class) at the callback function. I tryed to use call_user_func(), but doesnt work (becose in this way i miss the matches parameter). Is there a way to do that, or have i to separate the process (doing before preg_match_all, for each match retrieve the replace value, and then a simple preg_replace)?

  Read the article

• Accessing Static Methods on a Generic class in c#

  - by mrlane

  Hello, I have the following situation in code, which I suspect may be a bit dodgey: I have a class: abstract class DataAccessBase<T> : IDataAccess where T : AnotherAbstractClass This class DataAccessBase also has a static factory method which creates instances of derived classes of itself using an enum value in a which statement to decide which derived type to create: static IDataAccess CreateInstance(TypeToCreateEnum) Now, the types derived from DataAccessBase<T> are themselves NOT generic, they specify a type for T: class PoLcZoneData : DataAccessBase<PoLcZone> // PoLcZone is derived from AnotherAbstractClass So far I am not sure if this is pushing the limits of good use of generics, but what I am really concerned about is how to access the static CreateInstance() method in the first place: The way I am doing this at the moment is to simply pass any type T where T : AnotherAbstractClass. In particular I am passing AnotherAbstractClass itself. This allows compilation just fine, but it does seem to me that passing any type to a generic class just to get at the statics is a bit dodgey. I have actually simplified the situation somewhat as DataAccessBase<T> is the lower level in the inheritance chain, but the static factory methods exists in a middle tier with classes such as PoLcZoneData being the most derived on the only level that is not generic. What are peoples thoughts on this arrangement?

  Read the article

• Deserializing a FileStream on Client using WCF

  - by Grandpappy

  I'm very new to WCF, so I apologize in advance if I misstate something. This is using .NET 4.0 RC1. Using WCF, I am trying to deserialize a response from the server. The base response has a Stream as its only MessageBodyMember. public abstract class StreamedResponse { [MessageBodyMember] public Stream Stream { get; set; } public StreamedResponse() { this.Stream = Stream.Null; } } The derived versions of this class are actually what's serialized, but they don't have a MessageBodyMember attribute (they have other base types such as int, string, etc listed as MessageHeader values). [MessageContract] public class ChildResponse : StreamedResponse { [DataMember] [MessageHeader] public Guid ID { get; set; } [DataMember] [MessageHeader] public string FileName { get; set; } [DataMember] [MessageHeader] public long FileSize { get; set; } public ChildResponse() : base() { } } The Stream is always a FileStream, in my specific case (but may not always be). At first, WCF said FileStream was not a known type, so I added it to the list of known types and now it serializes. It also appears, at first glance, to deserialize it on the client's side (it's the FileStream type). The problem is that it doesn't seem to be usable. All the CanRead, CanWrite, etc are false, and the Length, Position, etc properties throw exceptions when being used. Same with ReadByte(). What am I missing that would keep me from getting a valid FileStream?

  Read the article

• How do I correctly use Unity to pass a ConnectionString to my repository classes?

  - by GenericTypeTea

  I've literally just started using the Unity Application Blocks Dependency Injection library from Microsoft, and I've come unstuck. This is my IoC class that'll handle the instantiation of my concrete classes to their interface types (so I don't have to keep called Resolve on the IoC container each time I want a repository in my controller): public class IoC { public static void Intialise(UnityConfigurationSection section, string connectionString) { _connectionString = connectionString; _container = new UnityContainer(); section.Configure(_container); } private static IUnityContainer _container; private static string _connectionString; public static IMovementRepository MovementRepository { get { return _container.Resolve<IMovementRepository>(); } } } So, the idea is that from my Controller, I can just do the following: _repository = IoC.MovementRepository; I am currently getting the error: Exception is: InvalidOperationException - The type String cannot be constructed. You must configure the container to supply this value. Now, I'm assuming this is because my mapped concrete implementation requires a single string parameter for its constructor. The concrete class is as follows: public sealed class MovementRepository : Repository, IMovementRepository { public MovementRepository(string connectionString) : base(connectionString) { } } Which inherits from: public abstract class Repository { public Repository(string connectionString) { _connectionString = connectionString; } public virtual string ConnectionString { get { return _connectionString; } } private readonly string _connectionString; } Now, am I doing this the correct way? Should I not have a constructor in my concrete implementation of a loosely coupled type? I.e. should I remove the constructor and just make the ConnectionString property a Get/Set so I can do the following: public static IMovementRepository MovementRepository { get { return _container.Resolve<IMovementRepository>( new ParameterOverrides { { "ConnectionString", _connectionString } }.OnType<IMovementRepository>() ); } } So, I basically wish to know how to get my connection string to my concrete type in the correct way that matches the IoC rules and keeps my Controller and concrete repositories loosely coupled so I can easily change the DataSource at a later date.

  Read the article

• When virtual inheritance IS a good design?

  - by 7vies

  EDIT3: Please be sure to clearly understand what I am asking before answering (there are EDIT2 and lots of comments around). There are (or were) many answers which clearly show misunderstanding of the question (I know that's also my fault, sorry for that) Hi, I've looked over the questions on virtual inheritance (class B: public virtual A {...}) in C++, but did not find an answer to my question. I know that there are some issues with virtual inheritance, but what I'd like to know is in which cases virtual inheritance would be considered a good design. I saw people mentioning interfaces like IUnknown or ISerializable, and also that iostream design is based on virtual inheritance. Would those be good examples of a good use of virtual inheritance, is that just because there is no better alternative, or because virtual inheritance is the proper design in this case? Thanks. EDIT: To clarify, I'm asking about real-life examples, please don't give abstract ones. I know what virtual inheritance is and which inheritance pattern requires it, what I want to know is when it is the good way to do things and not just a consequence of complex inheritance. EDIT2: In other words, I want to know when the diamond hierarchy (which is the reason for virtual inheritance) is a good design

  Read the article

• Generic list typecasting problem

  - by AJ

  Hello, I'm new to C# and am stuck on the following. I have a Silverlight web service that uses LINQ to query a ADO.NET entity object. e.g.: [OperationContract] public List<Customer> GetData() { using (TestEntities ctx = new TestEntities()) { var data = from rec in ctx.Customer select rec; return data.ToList(); } } This works fine, but what I want to do is to make this more abstract. The first step would be to return a List<EntityObject> but this gives a compiler error, e.g.: [OperationContract] public List<EntityObject> GetData() { using (TestEntities ctx = new TestEntities()) { var data = from rec in ctx.Customer select rec; return data.ToList(); } } The error is: Error 1 Cannot implicitly convert type 'System.Collections.Generic.List<SilverlightTest.Web.Customer>' to 'System.Collections.Generic.IEnumerable<System.Data.Objects.DataClasses.EntityObject>'. An explicit conversion exists (are you missing a cast?) What am i doing wrong? Thanks, AJ

  Read the article

• How to pass binary data between two apps using Content Provider?

  - by Viktor

  I need to pass some binary data between two android apps using Content Provider (sharedUserId is not an option). I would prefer not to pass the data (a savegame stored as a file, small in size < 20k) as a file (ie. overriding openFile()) since this would necessitate some complicated temp-file scheme to cope with concurrency with several content provider accesses and a running game. I would like to read the file into memory under a mutex lock and then pass the binary array in the simplest way possible. How do I do this? It seems creating a file in memory is not a possibility due to the return type of openFile(). query() needs to return a Cursor. Using MatrixCursor is not possible since it applies toString() to all stored objects when reading it. What do I need to do? Implement a custom Cursor? This class has 30 abstract methods. Do I read the file, put it in a SQLite db and return the cursor? The complexity of this seemingly simple task is mindboggling.

  Read the article

• Setting CommandTarget to selected control in a TabControl

  - by Bart

  I have a WPF window with a few buttons and a tabcontrol having a tab for each 'document' the user is working on. The tabcontrol uses a DataTemplate to render the data in ItemSource of the tabcontrol. The question: If one of the buttons is clicked, the command should be executed on the control rendering the document in the active tab, but I've no idea what I should set CommandTarget to. I tried {Binding ElementName=nameOfControlInDataTemplate} but that obviously doesn't work. I tried to make my problem a bit more abstract with the following code (no ItemSource and Document objects, but the idea is still the same). <Button Command="ApplicationCommands.Save" CommandTarget="{Binding ElementName=nestedControl}">Save</Button> <TabControl x:Name="tabControl"> <TabControl.Items> <TabItem Header="Header1">Item 1</TabItem> <TabItem Header="Header2">Item 2</TabItem> <TabItem Header="Header3">Item 3</TabItem> </TabControl.Items> <TabControl.ContentTemplate> <DataTemplate> <CommandTest:NestedControl Name="nestedControl"/> </DataTemplate> </TabControl.ContentTemplate> </TabControl> I tested the code by replacing the complete tabcontrol with only one single NestedControl, and then the command button just works. To be complete, here is the code of NestedControl: <UserControl x:Class="CommandTest.NestedControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <Grid> <Label x:Name="label" Content="Not saved"/> </Grid> </UserControl> And code behind: public partial class NestedControl : UserControl { public NestedControl() { CommandBindings.Add(new CommandBinding(ApplicationCommands.Save, CommandBinding_Executed)); InitializeComponent(); } private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e) { label.Content = "Saved"; } }

  Read the article

• Validation not bubbling up to my other models.

  - by DJTripleThreat

  Ok, I have a relationship between People, Users and Employees such that All Employees are Users and all Users are People. Person is an abstract class that User is derived from and Employee is derived from that. Now... I have an EmployeesController class and the create method looks like this: def create @employee = Employee.new(params[:employee]) @employee.user = User.new(params[:user]) @employee.user.person = Person.new(params[:person]) respond_to do |format| if @employee.save flash[:notice] = 'Employee was successfully created.' format.html { redirect_to(@employee) } format.xml { render :xml => @employee, :status => :created, :location => @employee } else format.html { render :action => "new" } format.xml { render :xml => @employee.errors, :status => :unprocessable_entity } end end end As you can see, when I'm using the :polymorphic => true clause, the way you access the super class is by doing something like @derived_class_variable.super_class_variable.super_super_etc. The Person class has a validates_presence_of :first_name and when it is satisfied, on my form, everything is OK. However, if I leave out the first name, it won't prevent the employee from being saved. What happens is that the employee record is saved but the person record isn't (because of the validation). How can I get the validation errors to show up in the flash object?

  Read the article

• using indexer to retrieve Linq to SQL object from datastore

  - by fearofawhackplanet

  class UserDatastore : IUserDatastore { ... public IUser this[Guid userId] { get { User user = (from u in _dataContext.Users where u.Id == userId select u).FirstOrDefault(); return user; } } ... } One of the developers in our team is arguing that an indexer in the above situation is not appropriate and that a GetUser(Guid id) method should be prefered. The arguments being that: 1) We aren't indexing into an in-memory collection, the indexer is basically performing a hidden SQL query 2) Using a Guid in an indexer is bad (FxCop flagged this also) 3) Returning null from an indexer isn't normal behaviour 4) An API user generally wouldn't expect any of this behaviour I agree to an extent with (most of) these points. But I'm also inclined to argue that one of the characteristics of Linq is to abstract the database access to make it appear that you're simply working with a bunch of collections, even though the lazy evaluation paradigm means those collections aren't evaluated until you run a query over them. It doesn't seem inconsistent to me to access the datastore in the same manner as if it was a concrete in-memory collection here. Also bearing in mind this is an inherited codebase which uses this pattern extensively and consistently, is it worth the refactoring? I accept that it might have been better to use a Get method from the start, but I'm not yet convinced that it's completely incorrect to be using an indexer. I'd be interested to hear all opinions, thanks.

  Read the article

• C# Inheritence: Choosing what repository based on type of inherited class

  - by Oskar Kjellin

  I have been making a program that downloads information about movies from the internet. I have a base class Title, which represents all titles. Movie, Serie and Episode are inherited from that class. To save them to the database I have 2 services, MovieService and SerieService. They in turn call repositories, but that is not important here. I have a method Save(Title title) which I am not very happy with. I check for what type the title is and then call the correct service. I would like to perhaps write like this: ITitleService service = title.GetService(); title.GetSavedBy(service); So I have an abstract method on Title that returns an ITitleSaver, which will return the correct service for the instance. My question is how should I implement ITitleSaver? If I make it accept Title I will have to cast it to the correct type before calling the correct overload. Which will lead to having to deal with casting once again. What is the best approach to dealing with this? I would like to have the saving logic in the corresponding class.

  Read the article

• Can't read from RSOP_RegistryPolicySetting WMI class in root\RSOP namespace

  - by JCCyC

  The class is documented in http://msdn.microsoft.com/en-us/library/aa375050%28VS.85%29.aspx And from this page it seems it's not an abstract class: http://msdn.microsoft.com/en-us/library/aa375084%28VS.85%29.aspx But whenever I run the code below I get an "Invalid Class" exception in ManagementObjectSearcher.Get(). So, does this class exist or not? ManagementScope scope; ConnectionOptions options = new ConnectionOptions(); options.Username = tbUsername.Text; options.Password = tbPassword.Password; options.Authority = String.Format("ntlmdomain:{0}", tbDomain.Text); scope = new ManagementScope(String.Format("\\\\{0}\\root\\RSOP", tbHost.Text), options); scope.Connect(); ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, new ObjectQuery("SELECT * FROM RSOP_RegistryPolicySetting")); foreach (ManagementObject queryObj in searcher.Get()) { wmiResults.Text += String.Format("id={0}\n", queryObj["id"]); wmiResults.Text += String.Format("precedence={0}\n", queryObj["precedence"]); wmiResults.Text += String.Format("registryKey={0}\n", queryObj["registryKey"]); wmiResults.Text += String.Format("valueType={0}\n", queryObj["valueType"]); } In the first link above, it lists as a requirement something called a "MOF": "Rsopcls.mof". Is this something I should have but have not? How do I obtain it? Is it necessary in the querying machine or the queried machine? Or both? I do have two copies of this file: C:\Windows>dir rsop*.mof /s Volume in drive C has no label. Volume Serial Number is 245C-A6EF Directory of C:\Windows\System32\wbem 02/11/2006 05:22 100.388 rsop.mof 1 File(s) 100.388 bytes Directory of C:\Windows\winsxs\x86_microsoft-windows-grouppolicy-base-mof_31bf3856ad364e35_6.0.6001.18000_none_f2c4356a12313758 19/01/2008 07:03 100.388 rsop.mof 1 File(s) 100.388 bytes Total Files Listed: 2 File(s) 200.776 bytes 0 Dir(s) 6.625.456.128 bytes free

  Read the article

• PHP OOP: Providing Domain Entities with "Identity"

  - by sunwukung

  Bit of an abstract problem here. I'm experimenting with the Domain Model pattern, and barring my other tussles with dependencies - I need some advice on generating Identity for use in an Identity Map. In most examples for the Data Mapper pattern I've seen (including the one outlined in this book: http://apress.com/book/view/9781590599099) - the user appears to manually set the identity for a given Domain Object using a setter: $UserMapper = new UserMapper; //returns a fully formed user object from record sets $User = $UserMapper->find(1); //returns an empty object with appropriate properties for completion $UserBlank = $UserMapper->get(); $UserBlank->setId(); $UserBlank->setOtherProperties(); Now, I don't know if I'm reading the examples wrong - but in the first $User object, the $id property is retrieved from the data store (I'm assuming $id represents a row id). In the latter case, however, how can you set the $id for an object if it has not yet acquired one from the data store? The problem is generating a valid "identity" for the object so that it can be maintained via an Identity Map - so generating an arbitrary integer doesn't solve it. My current thinking is to nominate different fields for identity (i.e. email) and demanding their presence in generating blank Domain Objects. Alternatively, demanding all objects be fully formed, and using all properties as their identity...hardly efficient. (Or alternatively, dump the Domain Model concept and return to DBAL/DAO/Transaction Scripts...which is seeming increasingly elegant compared to the ORM implementations I've seen...)

  Read the article

< Previous Page | 60 61 62 63 64 65 66 67 68 69 70 71  | Next Page >