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  • How can I display multiple django modelformset forms together?

    - by JT
    I have a problem with needing to provide multiple model backed forms on the same page. I understand how to do this with single forms, i.e. just create both the forms call them something different then use the appropriate names in the template. Now how exactly do you expand that solution to work with modelformsets? The wrinkle, of course, is that each 'form' must be rendered together in the appropriate fieldset. For example I want my template to produce something like this: <fieldset> <label for="id_base-0-desc">Home Base Description:</label> <input id="id_base-0-desc" type="text" name="base-0-desc" maxlength="100" /> <label for="id_likes-0-icecream">Want ice cream?</label> <input type="checkbox" name="likes-0-icecream" id="id_likes-0-icecream" /> </fieldset> <fieldset> <label for="id_base-1-desc">Home Base Description:</label> <input id="id_base-1-desc" type="text" name="base-1-desc" maxlength="100" /> <label for="id_likes-1-icecream">Want ice cream?</label> <input type="checkbox" name="likes-1-icecream" id="id_likes-1-icecream" /> </fieldset> I am using a loop like this to process the results for base_form, likes_form in map(None, base_forms, likes_forms): which works as I'd expect (I'm using map because the # of forms can be different). The problem is that I can't figure out a way to do the same thing with the templating engine. The system does work if I layout all the base models together then all the likes models after wards, but it doesn't meet the layout requirements.

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  • How can I map stored procedure result into a custom class with linq-to-sql?

    - by Remnant
    I have a stored procedure that returns a result set (4 columns x n Rows). The data is based on multiple tables within my database and provides a summary for each department within a corporate. Here is sample: usp_GetDepartmentSummary DeptName EmployeeCount Male Female HR 12 5 7 etc... I am using linq-to-sql to retrieve data from my database (nb - have to use sproc as it is something I have inherited). I would like to call the above sproc and map into a department class: public class Department { public string DeptName {get; set;} public int EmployeeCount {get; set;} public int MaleCount {get; set;} public int FemaleCount {get; set;} } In VS2008, I can drag and drop my sproc onto the methods pane of the linq-to-sql designer. When I examine the designer.cs the return type for this sproc is defined as: ISingleResult<usp_GetDepartmentSummaryResult> What I would like to do is amend this somehow so that it returns a Department type so that I can pass the results of the sproc as a strongly typed view: <% foreach (var dept in Model) { %> <ul> <li class="deptname"><%= dept.DeptName %></li> <li class="deptname"><%= dept.EmployeeCount %></li> etc... Any ideas how to achieve this? NB - I have tried amending the designer.cs and dbml xml file directly but with limited success. I admit to being a little out of my depth when it comes to updating those files directly and I am not sure it is best practice? Would be good to get some diretion. Thanks much

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  • suggestions for declarative GUI programming in Java

    - by Jason S
    I wonder if there are any suggestions for declarative GUI programming in Java. (I abhor visual-based GUI creator/editor software, but am getting a little tired of manually instantiating JPanels and Boxes and JLabels and JLists etc.) That's my overall question, but I have two specific questions for approaches I'm thinking of taking: JavaFX: is there an example somewhere of a realistic GUI display (e.g. not circles and rectangles, but listboxes and buttons and labels and the like) in JavaFX, which can interface with a Java sourcefile that accesses and updates various elements? Plain Old Swing with something to parse XUL-ish XML: has anyone invented a declarative syntax (like XUL) for XML for use with Java Swing? I suppose it wouldn't be hard to do, to create some code based on STaX which reads an XML file, instantiates a hierarchy of Swing elements, and makes the hierarchy accessible through some kind of object model. But I'd rather use something that's well-known and documented and tested than to try to invent such a thing myself. JGoodies Forms -- not exactly declarative, but kinda close & I've had good luck with JGoodies Binding. But their syntax for Form Layout seems kinda cryptic. edit: lots of great answers here! (& I added #3 above) I'd be especially grateful for hearing any experiences any of you have had with using one of these frameworks for real-world applications. p.s. I did try a few google searches ("java gui declarative"), just didn't quite know what to look for.

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  • SQL, MVC, Entity Framework

    - by Anthony
    Hi Im using the above technologies and have ran into what I presume is a design issue I have made. I have an Artwork table in my DB and have been able to add art (I now think of these as Digital Products) to a shopping cart + CartLine table fine. The system I have that adds art to galleries and user accounts etc works fine. Now the client wants to sell T-shirts, Mugs and Pens etc, 'HardwareProducts' so I have created a 'HardwareProducts' table. Now I have two different product types in two tables. I use GUID's as the PK's in both the HardwareProducts table and Artwork table. When a customer adds an item to their cart I store the GUID in the ProductID column in the CartItems table. The issue is the database will not know which table to reference when I bring the LineItem object up through my ORM to the front end. In OOP I can see how you would have a base class of Product, and then a DigitalProduct class and HardwareProduct class drived from it, but how do you model this in SQL Server and the Entity Framework please, or is there another way?

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  • How to return all records and whether a related record exists?

    - by David Glenn
    Using Entity Framework 4 CTP5 I have a basic model and a basic DbContext that works public class Customer { public int CustomerId { get; set; } public int Name { get; set; } //... public ICollection<Address> Addresses { get; set; } public bool HasAddress { get { return Addresses.Count > 0; } } } public class Address { public int AddressId { get; set; } public string StreetLine1 { get; set; } //.... public Customer Customer { get; set; } } How can I query my DbContext to return all customers and whether they have an address? A customer can have multiple addresses and I don't want to return all the addresses for each customer when I am only interested in whether they have an address or not. I use context.Customers.Include(c => c.Addresses) but that returns all addresses for each customer

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  • What's the best way to learn .NET?

    - by duffymo
    I've been developing Java EE for quite a while now. I've used WebLogic, Tomcat, Spring, and Hibernate extensively, so I have a mental model of what features are available and how things are developed and deployed. The problem that I have with .NET is that I don't have a clear mapping of its features onto Java EE. Here's what I know so far: Java EE - .NET Java - C# JAR - DLL WAR - ? (deployment in general) EAR - ? (deployment in general) Tomcat - IIS web server JSP - ASP? JDBC - ODBC JMS - MSMQ JTA - Microsoft Transaction Manager So much of the functionality that WebLogic handles appears to be dispersed throughout the Windows OS. My confusion kicks in when I see the waves of books at Borders - VB.NET, ASP.NET, C#, etc. If I'm not a VB programmer, would it be possible to stick with C# and write enterprise apps that are the equivalent of what I'm used to with Java EE? If there were a Top Three list of books to learn from, what would they be? The "Head First" series has certainly been successful for Java. http://www.amazon.com/Head-First-C-Brain-Friendly-Guides/dp/0596514824/ref=sr_1_1?ie=UTF8&s=books&qid=1224121193&sr=8-1 Equally well recommended for .NET learning? Thanks. - %

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  • Alternatives to the Entity Framework for Serving/Consuming an OData Interface

    - by Egahn
    I'm researching how to set up an OData interface to our database. I would like to be able to pull/query data from our DB into Excel, as a start. Eventually I would like to have Excel run queries and pull data over HTTP from a remote client, including authentication, etc. I've set up a working (rickety) prototype so far, using the ADO.NET Entity Data Model wizard in Visual Studio, and VSTO to create a test Excel worksheet with a button to pull from that ADO.NET interface. This works OK so far, and I can query the DB using Linq through the entities/objects that are created by the ADO.NET EDM wizard. However, I have started to run into some problems with this approach. I've been finding the Entity Framework difficult to work with (and in fact, also difficult to research solutions to, as there's a lot of chaff out there regarding it and older versions of it). An example of this is my being unable to figure out how to set the SQL command timeout (as opposed to the HTTP request timeout) on the DataServiceContext object that the wizard generates for my schema, but that's not the point of my question. The real question I have is, if I want to use OData as my interface standard, am I stuck with the Entity Framework? Are there any other solutions out there (preferably open source) which can set up, serve and consume an OData interface, and are easier to work with and less bloated than the Entity Framework? I have seen mention of NHibernate as an alternative, but most of the comparison threads I've seen are a few years old. Are there any other alternatives out there now? Thanks very much!

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  • Delete throws "deleted object would be re-saved by cascade"

    - by Greg
    I have following model: <class name="Person" table="Person" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <!-- plus some properties here --> </class> <class name="Event" table="Event" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <!-- plus some properties here --> </class> <class name="PersonEventRegistration" table="PersonEventRegistration" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <property name="IsComplete" type="Boolean" not-null="true" /> <property name="RegistrationDate" type="DateTime" not-null="true" /> <many-to-one name="Person" class="Person" column="PersonId" foreign-key="FK_PersonEvent_PersonId" cascade="all-delete-orphan" /> <many-to-one name="Event" class="Event" column="EventId" foreign-key="FK_PersonEvent_EventId" cascade="all-delete-orphan" /> </class> There are no properties pointing to PersonEventRegistration either in Person nor in Event. When I try to delete an entry from PersonEventRegistration, I get the following error: "deleted object would be re-saved by cascade" The problem is, I don't store this object in any other collection - the delete code looks like this: public bool UnregisterFromEvent(Person person, Event entry) { var registrationEntry = this.session .CreateCriteria<PersonEventRegistration>() .Add(Restrictions.Eq("Person", person)) .Add(Restrictions.Eq("Event", entry)) .Add(Restrictions.Eq("IsComplete", false)) .UniqueResult<PersonEventRegistration>(); bool result = false; if (null != registrationEntry) { using (ITransaction tx = this.session.BeginTransaction()) { this.session.Delete(registrationEntry); tx.Commit(); result = true; } } return result; } What am I doing wrong here?

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  • BeginInvoke on ObservableCollection not immediate.

    - by Padu Merloti
    In my code I subscribe to an event that happens on a different thread. Every time this event happens, I receive an string that is posted to the observable collection: Dispatcher currentDispatcher = Dispatcher.CurrentDispatcher; var SerialLog = new ObservableCollection<string>(); private void hitStation_RawCommandSent(object sender, StringEventArgs e) { string command = e.Value.Replace("\r\n", ""); Action dispatchAction = () => SerialLog.Add(command); currentDispatcher.BeginInvoke(dispatchAction, DispatcherPriority.Render); } The code below is in my view model (could be in the code behind, it doesn't matter in this case). When I call "hitstation.PrepareHit", the event above gets called a couple times, then I wait and call "hitStation.HitBall", and the event above gets called a couple more times. private void HitBall() { try { try { Mouse.OverrideCursor = Cursors.Wait; //prepare hit hitStation.PrepareHit(hitSpeed); Thread.Wait(1000); PlayWarning(); //hit hitStation.HitBall(hitSpeed); } catch (TimeoutException ex) { MessageBox.Show("Timeout hitting ball: " + ex.Message); } } finally { Mouse.OverrideCursor = null; } } The problem I'm having is that the ListBox that is bound to my SerialLog gets updated only when the HitBall method finishes. I was expecting seeing a bunch of updates from the PrepareHit, a pause and then a bunch more updates from the HitBall. I've tried a couple of DispatcherPriority arguments, but they don't seem to have any effect.

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  • Can't log in with a valid password using Authlogic and Ruby on Rails?

    - by kbighorse
    We support a bit of an unusual scheme. We don't require a password on User creation, and use password_resets to add a password to the user later, on demand. The problem is, once a password is created, the console indicates the password is valid: user.valid_password? 'test' = true but in my UserSessions controller, @user_session.save returns false using the same password. What am I not seeing? Kimball UPDATE: Providing more details, here is the output when saving the new password: Processing PasswordResetsController#update (for 127.0.0.1 at 2011-01-31 14:01:12) [PUT] Parameters: {"commit"="Update password", "action"="update", "_method"="put", "authenticity_token"="PQD4+eIREKBfHR3/fleWuQSEtZd7RIvl7khSYo5eXe0=", "id"="v3iWW5eD9P9frbEQDvxp", "controller"="password_resets", "user"={"password"="johnwayne"}} The applicable SQL is: UPDATE users SET updated_at = '2011-01-31 22:01:12', crypted_password = 'blah', perishable_token = 'blah', password_salt = 'blah', persistence_token = 'blah' WHERE id = 580 I don't see an error per se, @user_session.save just returns false, as if the password didn't match. I skip validating passwords in the User model: class User < ActiveRecord::Base acts_as_authentic do |c| c.validate_password_field = false end Here's the simplified controller code: def create logger.info("SAVED SESSION? #{@user_session.save}") end which outputs: Processing UserSessionsController#create (for 127.0.0.1 at 2011-01-31 14:16:59) [POST] Parameters: {"commit"="Login", "user_session"={"remember_me"="0", "password"="johnwayne", "email"="[email protected]"}, "action"="create", "authenticity_token"="PQD4+eIREKBfHR3/fleWuQSEtZd7RIvl7khSYo5eXe0=", "controller"="user_sessions"} User Columns (2.2ms) SHOW FIELDS FROM users User Load (3.7ms) SELECT * FROM users WHERE (users.email = '[email protected]') ORDER BY email ASC LIMIT 1 SAVED SESSION? false CACHE (0.0ms) SELECT * FROM users WHERE (users.email = '[email protected]') ORDER BY email ASC LIMIT 1 Redirected to http://localhost:3000/login Lastly, the console indicates that the new password is valid: $ u.valid_password? 'johnwayne' = true Would love to do it all in the console, is there a way to load UserSession controller and call methods directly? Kimball

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  • Using Silverlight for Views in ASP.Net MVC - a bad idea?

    - by bplus
    I'm currently writing a small application for use internally at my office. I started out teaching myself some MVC (I've been a C# dev for 3 years). One of the main requirements is editable grids - I quickly realised that silverlight (i have zero silverlight experience) could be a big help in this. I've managed to create a proof of concept of getting MVC and silverlight to talk back an forth by combining these two techniques: Creating a Rest API using MVC MVC SilverLight I also got some help on stackoverflow: silverlight-grids-mvc-http-post Essentially all I'm doing is embedding a silver light object in a view. Serializing the Model data as JSON and passing it to silverlight(using intit params written into the response). The silverlight object can post data back to the controller as JSON. So far this seems like it could work quite well. However I am a bit concerned that I could be painting myself into a corner with this approach, as in I don't have much experience with either technology so I'm worried I'm going get hit with something further down the line that I won't be able to work around. Has anybody else tried doing this? Any advice would be much appreciated!

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  • Handle row deletion in UITableViewController

    - by Kamchatka
    Hello, I hava a UINavigationController. The first level is a UITableViewController, the second level just shows details on one of the items of the table view. In this detail view, I can delete the item. It deletes the underlying managed object. When I pop back to the view, I have a crash. I understand why, it's because I didn't update the cached array that contains the data. I looked at several tutorials and I don't exactly understand how am I supposed to handle deletion. Maybe I don't understand exactly where I should fetch the objects in the model. Should I do a query for every cellForRowAtIndexPath and take the item in the result at position indexPath.row? It doesn't look efficient. Should I check for changes somewhere and recache the whole query in an array. I would think CoreData would provide something more natural but I couldn't find it so far. Thanks in advance.

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  • Why is Core Data not persisting these changes to disk?

    - by scott
    I added a new entity to my model and it loads fine but no changes made in memory get persisted to disk. My values set on the car object work fine in memory but aren't getting persisted to disk on hitting the home button (in simulator). I am using almost exactly the same code on another entity in my application and its values persist to disk fine (core data - sqlite3); Does anyone have a clue what I'm overlooking here? Car is the managed object, cars in an NSMutableArray of car objects and Car is the entity and Visible is the attribute on the entity which I am trying to set. Thanks for you assistance. Scott - (void)viewDidLoad { myAppDelegate* appDelegate = (myAppDelegate*)[[UIApplication sharedApplication] delegate]; NSManagedObjectContext* managedObjectContex = appDelegate.managedObjectContext; NSFetchRequest* request = [[NSFetchRequest alloc] init]; NSEntityDescription* entity = [NSEntityDescription entityForName:@"Car" inManagedObjectContext:managedObjectContex]; [request setEntity:entity]; NSSortDescriptor* sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"Name" ascending:YES]; NSArray* sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; [sortDescriptors release]; [sortDescriptor release]; NSError* error = nil; cars = [[managedObjectContex executeFetchRequest:request error:&error] mutableCopy]; if (cars == nil) { NSLog(@"Can't load the Cars data! Error: %@, %@", error, [error userInfo]); } [request release]; } - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath*)indexPath { Car* car = [cars objectAtIndex:indexPath.row]; if (car.Visible == [NSNumber numberWithBool:YES]) { car.Visible = [NSNumber numberWithBool:NO]; [tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryNone; } else { car.Visible = [NSNumber numberWithBool:YES]; [tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryCheckmark; } }

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  • Python unittest (using SQLAlchemy) does not write/update database?

    - by Jerry
    Hi, I am puzzled at why my Python unittest runs perfectly fine without actually updating the database. I can even see the SQL statements from SQLAlchemy and step through the newly created user object's email -- ...INFO sqlalchemy.engine.base.Engine.0x...954c INSERT INTO users (user_id, user_name, email, ...) VALUES (%(user_id)s, %(user_name)s, %(email)s, ...) ...INFO sqlalchemy.engine.base.Engine.0x...954c {'user_id': u'4cfdafe3f46544e1b4ad0c7fccdbe24a', 'email': u'[email protected]', ...} > .../tests/unit_tests/test_signup.py(127)test_signup_success() -> user = user_q.filter_by(user_name='test').first() (Pdb) n ...INFO sqlalchemy.engine.base.Engine.0x...954c SELECT users.user_id AS users_user_id, ... FROM users WHERE users.user_name = %(user_name_1)s LIMIT 1 OFFSET 0 ...INFO sqlalchemy.engine.base.Engine.0x...954c {'user_name_1': 'test'} > .../tests/unit_tests/test_signup.py(128)test_signup_success() -> self.assertTrue(isinstance(user, model.User)) (Pdb) user <pweb.models.User object at 0x9c95b0c> (Pdb) user.email u'[email protected]' Yet at the same time when I login to the test database, I do not see the new record there. Is it some feature from Python/unittest/SQLAlchemy/Pyramid/PostgreSQL that I'm totally unaware of? Thanks. Jerry

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  • Declaring a string array in class header file - compiler thinks string is variable name?

    - by Dave
    Hey everybody, I need a bit of a hand with declaring a string array in my class header file in C++. atm it looks like this: //Maze.h #include <string> class Maze { GLfloat mazeSize, mazeX, mazeY, mazeZ; string* mazeLayout; public: Maze ( ); void render(); }; and the constructor looks like this: //Maze.cpp #include <GL/gl.h> #include "Maze.h" #include <iostream> #include <fstream> Maze::Maze( ) { cin >> mazeSize; mazeLayout = new string[mazeSize]; mazeX = 2/mazeSize; mazeY = 0.25; mazeZ = 2/mazeSize; } I'm getting a compiler error that says: In file included from model-view.cpp:11: Maze.h:14: error: ISO C++ forbids declaration of ‘string’ with no type Maze.h:14: error: expected ‘;’ before ‘*’ token and the only sense that makes to me is that for some reason it thinks I want string as a variable name not as a type declaration. If anybody could help me out that would be fantastic, been looking this up for a while and its giving me the shits lol. Cheers guys

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  • ruby/datamapper: Refactor class methods to module

    - by DeSchleib
    Hello, i've the following code and tried the whole day to refactor the class methods to a sperate module to share the functionality with all of my model classes. Code (http://pastie.org/974847): class Merchant include DataMapper::Resource property :id, Serial [...] class << self @allowed_properties = [:id,:vendor_id, :identifier] alias_method :old_get, :get def get *args [...] end def first_or_create_or_update attr_hash [...] end end end I'd like to archive something like: class Merchant include DataMapper::Resource include MyClassFunctions [...] end module MyClassFunctions def get [...] def first_or_create_or_update[...] end => Merchant.allowed_properties = [:id] => Merchant.get( :id=> 1 ) But unfortunately, my ruby skills are to bad. I read a lot of stuff (e.g. here) and now i'm even more confused. I stumbled over the following two points: alias_method will fail, because it will dynamically defined in the DataMapper::Resource module. How to get a class method allowed_properties due including a module? What's the ruby way to go? Many thanks in advance.

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  • Designing a general database interface in PHP

    - by lamas
    I'm creating a small framework for my web projects in PHP so I don't have to do the basic work over and over again for every new website. It is not my goal to create a second CakePHP or Codeigniter and I'm also not planning to build my websites with any of the available frameworks as I prefer to use things I've created myself in general. I have no problems in designing that framework when it comes to parts like the core structure, request handling, and so on but I'm getting stuck with designing the database interface for my modules. I've already thought about using the MVC pattern but thought that it would be a bit of a overkill. So the exact problem I'm facing is how my frameworks modules (viewCustomers could be a module, for example) should interact with the database. Is it a good idea to write SQL directly in PHP (mysql_query( 'SELECT firstname, lastname(.....))? How could I abstract a query like SELECT firstname, lastname FROM customers WHERE id=X Would MySQL helper functions like $this->db->get( array('firstname', 'lastname'), array('id'=>X) ) be a good idea? I suppose not because they actually make everything more complicated by requiring arrays to be created and passed. Is the Model pattern from MVC my only real option?

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  • What MS technology to use for HTTP service returning XML?

    - by Borek
    I need to create a service that: accepts HTTP requests (with query string or HTTP POST parameters) does some processing on the requests (checking if the request is valid, authentication etc.) reads data from a custom store (another HTTP call in our case) returns the result as custom XML (defined with XSD) I'm trying to think of various MS technologies that could help me and how good they would be for this scenario (pretty standard one I guess). The tasks above are relatively separate, this is what comes to mind: HTTP front-end: ASP.NET Web Forms ASP.NET MVC (seems more appropriate here as I won't need server controls, view state etc.) WCF? Don't know much about it or how well it would suit my task. Custom logic on the server: this will probably be a generic C# code in all cases (sometimes "plugged into" or called from MVC controllers or some equivalent place in other technologies) Reading data from internal data stores: As said, this is another HTTP server in our case. Options that come to mind: Just read the data using something like WebClient (Just theoretically) implement a LINQ provider (Just even more theoretically) implement an EF provider Output the data as custom XML: Linq2XML Serialization? Is it flexible enough? Does WCF provide some tools for this? Some "OXM" - Object/XML mapper if there is something like that for .NET I may be wrong in many of my assumptions, this is just a quick list that comes to mind after a quick research. Some general notes / questions: Testing is important Solution with a clear domain model would be much preferred over the one without Can Entity Framework actually help somewhere in my scenario? If so, where and how? Would WCF be an appropriate technology for this? I don't know much about it.

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  • How to load entities into readonly collections using the entity framework

    - by Anton P
    I have a POCO domain model which is wired up to the entity framework using the new ObjectContext class. public class Product { private ICollection<Photo> _photos; public Product() { _photos = new Collection<Photo>(); } public int Id { get; set; } public string Name { get; set; } public virtual IEnumerable<Photo> Photos { get { return _photos; } } public void AddPhoto(Photo photo) { //Some biz logic //... _photos.Add(photo); } } In the above example i have set the Photos collection type to IEnumerable as this will make it read only. The only way to add/remove photos is through the public methods. The problem with this is that the Entity Framework cannot load the Photo entities into the IEnumerable collection as it's not of type ICollection. By changing the type to ICollection will allow callers to call the Add mentod on the collection itself which is not good. What are my options?

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  • Write a program which works out which is the lowest priced computer in an ArrayList of computer obje

    - by Eoin
    Hello everybody! I am trying to study some java and cannot get my head around this question! Any help would be really appreciated and would help me in further studies! Thank you so much in advance! Eoin from Dublin, Ireland. ArrayList of Objects Write a program which works out which is the lowest priced computer in an ArrayList of computer objects. You should have two classes, one called ComputerTest, and the other called Computer. In the ComputerTest class you should: Have a main method which declares an ArrayList of type Computer called computerList, each element of which represents a computer. Initialise the first three entries of the ArrayList Call a static method which prints out the lowest price computer, called lowestPrice The parameter of this method is (i) an ArrayList of type Computer i.e. ArrayList data Sample output: The lowest priced computer is the Cheapo400 at 399 euro. The Computer class should have: Private instance variables: manufacturer, model, price and quality. Quality is a rating from 1 to 10. public get and set methods to retrieve and set/change the value of the four instance variables a default constructor a constructor that takes four parameters

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  • Using boost asio for pub/sub style tcp in a game loop

    - by unohoo
    I have been reading through the boost asio documentation for a couple of hours now, and while I think the documentation is really great, I am still left a bit confused on how to implement the system that I need. I have to stream info, from a game engine, to a list of computers over tcp. One snag is that, unlike traditional pub/sub, the computer that does the distribution of info is actually the computer that has to connect to the subscribers as well (instead of the subscribers registering with the publisher). This is done via a config file - a list of ip's/ports along with the data that they each require. The subscribers listen, but do not know the ip of the publisher. (As a side note, I'm quite new to network programming, so maybe I'm missing something .. but it's strange that I do not find much information regarding this style of "inverted" client-server model..) I am looking for suggestions for the implementation of such a system using boost asio. Of course I have to integrate the networking into an already existing engine, so with regards to that: What would be a good way to handle messages being sent to multiple computers every frame? Use async_write, call io_service.run and then reset every frame? Would having io_service.run have its own thread be better? Or should I just use threads and use blocking writes?

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  • Are document-oriented databases any more suitable than relational ones for persisting objects?

    - by Owen Fraser-Green
    In terms of database usage, the last decade was the age of the ORM with hundreds competing to persist our object graphs in plain old-fashioned RMDBS. Now we seem to be witnessing the coming of age of document-oriented databases. These databases are highly optimized for schema-free documents but are also very attractive for their ability to scale out and query a cluster in parallel. Document-oriented databases also hold a couple of advantages over RDBMS's for persisting data models in object-oriented designs. As the tables are schema-free, one can store objects belonging to different classes in an inheritance hierarchy side-by-side. Also, as the domain model changes, so long as the code can cope with getting back objects from an old version of the domain classes, one can avoid having to migrate the whole database at every change. On the other hand, the performance benefits of document-oriented databases mainly appear to come about when storing deeper documents. In object-oriented terms, classes which are composed of other classes, for example, a blog post and its comments. In most of the examples of this I can come up with though, such as the blog one, the gain in read access would appear to be offset by the penalty in having to write the whole blog post "document" every time a new comment is added. It looks to me as though document-oriented databases can bring significant benefits to object-oriented systems if one takes extreme care to organize the objects in deep graphs optimized for the way the data will be read and written but this means knowing the use cases up front. In the real world, we often don't know until we actually have a live implementation we can profile. So is the case of relational vs. document-oriented databases one of swings and roundabouts? I'm interested in people's opinions and advice, in particular if anyone has built any significant applications on a document-oriented database.

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  • Breeze Expand not working on WebAPI with EF

    - by Rodney
    I have published a WebAPI service which returns a list of items. I am implementing Breeze and have managed to get it basically working with filtering/sorting. However, the Expand is not working. http://www.ftter.com/desktopmodules/framework/api/dare/dares/?$filter=DareId%20eq%2010&expand%20eq%20ToUser You can see the ToUserId ForeignKey in the response above, but the ToUser properties are NULL (the user definitely exists) You can see the ToUser EF navigation property in the metadata. When I use .Include on the server side I can populate it with EF, but I don't want to do this. [HttpGet] [Queryable(AllowedQueryOptions = AllowedQueryOptions.All)] public HttpResponseMessage Dares() { var response = Request.CreateResponse(HttpStatusCode.OK, (IQueryable<Dare>)contextProvider.Context.Dares); return ControllerUtilities.GetResponseWithCorsHeader(response); } and here is the generated class from my EF model (using Database First) public partial class Dare { public int DareId { get; set; } public int ToUserId { get; set; } public virtual User ToUser { get; set; } }

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  • Seed has_many relation using mass assignment

    - by rnd
    Here are my two models: class Article < ActiveRecord::Base attr_accessible :content has_many :comments end class Comment < ActiveRecord::Base attr_accessible :content belongs_to :article end And I'm trying to seed the database in seed.rb using this code: Article.create( [{ content: "Hi! This is my first article!", comments: [{content: "It sucks"}, {content: "Best article ever!"}] }], without_protection: true) However rake db:seed gives me the following error message: rake aborted! Comment(#28467560) expected, got Hash(#13868840) Tasks: TOP => db:seed (See full trace by running task with --trace) It is possible to seed the database like this? If yes a follow-up question: I've searched some and it seems that to do this kind of (nested?) mass assignment I need to add 'accepts_nested_attributes_for' for the attributes I want to assign. (Possibly something like 'accepts_nested_attributes_for :article' for the Comment model) Is there a way to allow this similar to the 'without_protection: true'? Because I only want to accept this kind of mass assignment when seeding the database.

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  • Bind button visibility to the expresion (C#)

    - by drasto
    I have a delete button in each row of GridView (component ASP.NET). I want some of the delete buttons to be invisible. The visibility of the delete button should depend on the data that are back the row. GridView is backed by EntityDataSource. GridView displays entities called Category, one instance in each row. Entity Category has (besides others) also a field of type EntityCollection. Name of that field is Items. Basically I want to allow user to delete a row only if the Items field of backing Category entity is an empty collection. I cannot make up the binding of Visible property. I have no experience with bindings and Google does not really help. This is how the button looks right now: <asp:Button ID="DeleteButton" runat="server" CommandName="Delete" Text="Delete" Visible=??? ></asp:Button> I don't know what should replace ???. The button schold be visible only when this expression evaluates to true: ((SimpleEShop.Model.Category) dataItem).Items.LongCount() <= 0 where dataItem variable contains data of current row in the table. What is the binding that I need ?

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