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  • access properties of current model in has_many declaration

    - by seth.vargo
    Hello, I didn't exactly know how to pose this question other than through example... I have a class we will call Foo. Foo :has_many Bar. Foo has a boolean attribute called randomize that determines the order of the the Bars in the :has_many relationship: class CreateFoo < ActiveRecord::Migration def self.up create_table :foos do |t| t.string :name t.boolean :randomize, :default => false end end end   class CreateBar < ActiveRecord::Migration def self.up create_table :bars do |t| t.string :name t.references :foo end end end   class Bar < ActiveRecord::Base belongs_to :foo end   class Foo < ActiveRecord::Base # this is the line that doesn't work has_many :bars, :order => self.randomize ? 'RAND()' : 'id' end How do I access properties of self in the has_many declaration? Things I've tried and failed: creating a method of Foo that returns the correct string creating a lambda function crying Is this possible? UPDATE The problem seems to be that the class in :has_many ISN'T of type Foo: undefined method `randomize' for #<Class:0x1076fbf78> is one of the errors I get. Note that its a general Class, not a Foo object... Why??

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  • How to take a collection of bytes and pull typed values out of it?

    - by Pat
    Say I have a collection of bytes var bytes = new byte[] {0, 1, 2, 3, 4, 5, 6, 7}; and I want to pull out a defined value from the bytes as a managed type, e.g. a ushort. What is a simple way to define what types reside at what location in the collection and pull out those values? One (ugly) way is to use System.BitConverter and a Queue or byte[] with an index and simply iterate through, e.g.: int index = 0; ushort first = System.BitConverter.ToUint16(bytes, index); index += 2; // size of a ushort int second = System.BitConverter.ToInt32(bytes, index); index += 4; ... This method gets very, very tedious when you deal with a lot of these structures! I know that there is the System.Runtime.InteropServices.StructLayoutAttribute which allows me to define the locations of types inside a struct or class, but there doesn't seem to be a way to import the collection of bytes into that struct. If I could somehow overlay the struct on the collection of bytes and pull out the values, that would be ideal. E.g. Foo foo = (Foo)bytes; // doesn't work because I'd need to implement the implicit operator ushort first = foo.first; int second = foo.second; ... [StructLayout(LayoutKind.Explicit, Size=FOO_SIZE)] public struct Foo { [FieldOffset(0)] public ushort first; [FieldOffset(2)] public int second; } Any thoughts on how to achieve this?

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  • My UL child label elements disappear in IE on accordion menu opening

    - by Scott B
    I've got an app that's working pretty flawlessly in Chrome and FF, however, when I view it in IE, all is well until I click on a header element to activate it (jQuery accordion). What happens then is that I see a brief flash where the content is there, then suddenly the entire left column disappears. This column is generated by a floated label element with a class of ".left" as seen below... <ul class="menu collapsible"> <li class='expand sectionTitle'><a href='#'>General Settings</a> <ul class='acitem'> <li class="section"> <label class="left">This item if floated left with a defined width of 190px via css. This is the item that's disappearing after a brief display</label> <input class="input" value="input element here" /> <label class="description">This element has a margin-left:212px; set via css in order to be positioned to the right of the label element as if in an adjacent table cell. When I add a max-width property to this element, it disappears in IE too!</label> </li> </ul> </li> </ul> As you can see from the comments in the code above (for the two label elements) the description label disappears once I set a max-width on it. It shows up fine otherwise.

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  • LNK2019 Against CArray Add, GetAt, GetSize, all includes are present

    - by David J
    I'm having some issues trying to Compile a DLL, but I just can't see where this linking error is coming from. My LNK2019 is: Exports.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: int __thiscall CArray<struct HWND__ *,struct HWND__ *>::Add(struct HWND__ *)" (__imp_?Add@? $CArray@PAUHWND__@@PAU1@@@QAEHPAUHWND__@@@Z) referenced in function "int __stdcall _Disable(struct HWND__ *,long)" (?_Disable@@YGHPAUHWND__@@J@Z) Disable(...) is... static BOOL CALLBACK _Disable(HWND hwnd, LPARAM lParam) { CArray<HWND, HWND>* pArr = (CHWndArray*)lParam; if(::IsWindowEnabled(hwnd) && ::IsWindowVisible(hwnd)) { pArr->Add(hwnd); ::Enable(hwnd, FALSE); } } This is the first function in Exports.cpp; right above it is #include <afxtempl.h> I have the Windows 7.1 SDK installed (and have tried reinstalling both that and VS2010). The exact same project compiles perfectly fine on other machines, so it can't be the code itself.. I've spent countless errors researching, which led to desperate attempts of just changing random values in the solution file, including different Windows headers, etc. My last resort is getting to be just reinstalling the OS completely (assuming it's actually a problem with the Windows SDK being incorrect or something). Any suggestions at all would be a huge help. EDIT: I've added /showIncludes on the cpp giving issues, and I do see afxtempl.h being included. It's being included multiple times due to other headers including it, but it is there (and it is from the same directory every time): 1> Note: including file: C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\atlmfc\include\afxtempl.h

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  • HTML/Javascript: Selecting uncles/aunts

    - by DavidR
    So I have some code, <div class="chunk" id=""> <div class="chunkContent"> <div class="textLeft" ></div> <div class="textRight" ></div> <div class="notes border">Notes...</div> </div> <div class="tools fl"> <div class="toggleNotes border">n</div> <div class="addChunk border">+</div> </div> </div> Now, the two divs nested withing div.tools are small buttons. div.toggleNotes I need to select div.notes in a javascript/jquery function. div.addChunk I need to select the fisrt div, div.chunk. Currently, I am doing this by: $(".addChunk").live('click', (function(){create_chunk(this.parentNode.parentNode)})) $(".toggleNotes").live('click',function(){toggle_notes(this.parentNode.parentNode.firstElementChild.lastElementChild)}) Is there a better (i.e., more proper) way to do this than to string together parentNotes and firstElementChild's and etc.? I'm basically looking around the DOM tab in firebug.

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  • "Abstract static" method - how?

    - by polyglot
    There are already several SO questions on why there is not abstract static method/field as such, but I'm wondering about how one would go about implementing the following psuedo-code: class Animal { abstract static int getNumberOfLegs(); // not possible } class Chicken inherits Animal { static int getNumberOfLegs() { return 2; } class Dog inherits Animal { static int getNumberOfLegs() { return 4; } Here is the problem: Assuming that I want make sure that every class that inherits Animal to contain getNumberOfLegs() method (i.e. almost like an interface, except I do want the abstract class to implement several methods that are common to all child classes, hence pure interface does not work here). getNumberOfLegs() obviously should be a static method (assuming that in a perfect world we dont' have crippled chicken and dogs so getNumberOfLegs is not instance-dependent). Without an "abstract static" method/field, one can either leave the method out from Animal class, then there is the risk that some child class do not have that method. Or one can make getNumberOfLegs an instance method, but then one would have to instantiate a class to find out how many legs that animal has - even though it is not necessary. How do one usually go about implementing this situation?

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  • Easy ways to investigate unknown Python APIs

    - by jedi_coder
    When studying a snippet of unknown Python code, I occasionally bump into the varName.methodName() pattern. To figure out what's this, I shall study the code more, find where varName was instantiated, find its type. So if varName proves to be an instance of ClassName class, I would knew that methodName() is a method of ClassName. Sometimes varName == self and methodName() is a method of this class, or a method inherited from some other class, if the current class is subclassing some other classes. Are there quick ways / tools that could take 'methodName' as input, scan over all installed Python modules and show which classes have methodName()? The closest thing related to this I know of is ipython. If I type a class name, then dot ('.') then TAB, it can show the class members. Instead of a class I could use a name of an object (which is an instance of a certain class) and it would work too. As soon as I choose a method name from the provided options, I can type '?' or '??' and get some help if there's a docstring. I wonder if ipython can do some intelligent scanning based only on 'methodName' string. If you know alternatives to ipython that could possibly help with this, please do suggest them.

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  • clang does not compile but g++ does

    - by user1095108
    Can someone help me with this code: #include <type_traits> #include <vector> struct nonsense { }; template <struct nonsense const* ptr, typename R> typename std::enable_if<!std::is_void<R>::value, int>::type fo(void* const) { return 0; } template <struct nonsense const* ptr, typename R> typename std::enable_if<std::is_void<R>::value, int>::type fo(void* const) { return 1; } typedef int (*func_type)(void*); template <std::size_t O> void run_me() { static struct nonsense data; typedef std::pair<char const* const, func_type> pair_type; std::vector<pair_type> v; v.push_back(pair_type{ "a", fo<&data, int> }); v.push_back(pair_type{ "b", fo<&data, void> }); } int main(int, char*[]) { run_me<2>(); return 0; } clang-3.3 does not compile this code, but g++-4.8.1 does, which of the two compiler is right? Is something wrong with the code, as I suspect? The error reads: a.cpp:32:15: error: no matching constructor for initialization of 'pair_type' (aka 'pair<const char *const, func_type>') v.push_back(pair_type{ "a", fo<&data, int> }); ^ ~~~~~~~~~~~~~~~~~~~~~~~ a.cpp:33:15: error: no matching constructor for initialization of 'pair_type' (aka 'pair<const char *const, func_type>') v.push_back(pair_type{ "b", fo<&data, void> }); ^ ~~~~~~~~~~~~~~~~~~~~~~~~

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  • content_tag_for a collection in Rails?

    - by Nick
    I have a Post model. Posts have many Comments. I want to generate a <ul> element for post.comments using content_tag_for. Ideally, it'd produce <ul id="comments_post_7" class="comments"> ... </ul> where 7 is the ID of the Post. The closest I can get uses <% content-tag-for :ul post, :comments do %> which produces <ul id="comments_post_7" class="post"> ... </ul> which is pretty close, except for the class="post". Using :class => :comments in the content_tag_for yields class="post comments", but I just want class="comments". It seems logical that I'd be able to use something like <% content_tag_for :ul post.comments do %> but, sadly, that yields <ul id="array_2181653100" class="array"> ... </ul> I've searched far and wide. I feel like I'm missing some elegant way to do this. Am I? Because, seriously, <ul id="comments_post_<%= post.id %>" class="comments"> is painful.

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  • C++ private inheritance and static members/types

    - by WearyMonkey
    I am trying to stop a class from being able to convert its 'this' pointer into a pointer of one of its interfaces. I do this by using private inheritance via a middle proxy class. The problem is that I find private inheritance makes all public static members and types of the base class inaccessible to all classes under the inheriting class in the hierarchy. class Base { public: enum Enum { value }; }; class Middle : private Base { }; class Child : public Middle { public: void Method() { Base::Enum e = Base::value; // doesn't compile BAD! Base* base = this; // doesn't compile GOOD! } }; I've tried this in both VS2008 (the required version) and VS2010, neither work. Can anyone think of a workaround? Or a different approach to stopping the conversion? Also I am curios of the behavior, is it just a side effect of the compiler implementation, or is it by design? If by design, then why? I always thought of private inheritance to mean that nobody knows Middle inherits from Base. However, the exhibited behavior implies private inheritance means a lot more than that, in-fact Child has less access to Base than any namespace not in the class hierarchy!

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  • Get type of the parameter from list of objects, templates, C++

    - by CrocodileDundee
    This question follows to my previous question Get type of the parameter, templates, C++ There is the following data structure: Object1.h template <class T> class Object1 { private: T a1; T a2; public: T getA1() {return a1;} typedef T type; }; Object2.h template <class T> class Object2: public Object1 <T> { private: T b1; T b2; public: T getB1() {return b1;} } List.h template <typename Item> struct TList { typedef std::vector <Item> Type; }; template <typename Item> class List { private: typename TList <Item>::Type items; }; Is there any way how to get type T of an object from the list of objects (i.e. Object is not a direct parameter of the function but a template parameter)? template <class Object> void process (List <Object> *objects) { typename Object::type a1 = objects[0].getA1(); // g++ error: 'Object1<double>*' is not a class, struct, or union type } But his construction works (i.e. Object represents a parameter of the function) template <class Object> void process (Object *o1) { typename Object::type a1 = o1.getA1(); // OK }

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  • JQueryMobile 1.1.1 List items not anchoring to the left

    - by user1664935
    I'm trying to create a simple thumbnail list, the code is pretty much copied off jqm docs pages. However, when I use the code below the button element of the list isn't anchored to the left of the list item and instead appears centered...Can anyone help me? It's driving me crazy! I haven't got any styles in other than what is in the jquerymobile default page template <div id="listDiv" class="ui-content" data-role="main"> <div id="listInformation" data-role="content-primary"> <ul id="swipeMeChildrenList" data-role="listview" class="ui-listview"> <li data-corners="false" data-shadow="false" data-iconshadow="true" data-wrapperels="div" data-icon="arrow-r" data-iconpos="right" data-theme="c" class="ui-btn ui-btn-icon-right ui-li-has-arrow ui-li ui-btn-up-c"> <div class="ui-btn-inner ui-li"> <div class="ui-btn-text"> <a href="index.html" class="ui-link-inherit"> <img src="images/album-p.jpg" class="ui-li-thumb"> <p>Ha</p> </a> </div> <span class="ui-icon ui-icon-arrow-r ui-icon-shadow">&nbsp;</span> </div> </li> </ul> </div> </div>

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  • What are the javascript performance tradeoffs in adding id's to dom elements?

    - by Blinky
    For example, I have a website which has a dynamically-generated segment of its dom which looks roughly like this: <div id="master"> <div class="child"> ... </div> <div class="child"> ... </div> <div class="child"> ... </div> ... <div class="child"> ... </div> </div> There might be hundreds of child elements in this manner, and they, too, might have yet more children. At present, none of them have id's except for the master. Javascript manipulates them via dom-walking. It's a little scary. I'd like to add id's, e.g.: <div id="master"> <div id="child1" class="child"> ... </div> <div id="child2" class="child"> ... </div> <div id="child3" class="child"> ... </div> ... <div id="childN" class="child"> ... </div> </div> What are the tradeoffs in adding id's to these divs? Certainly, jQuery must maintain a hash of id's, so there's going to be some sort of performance hit. Any general guidelines in when adding additional id's is a bad idea? Is jQuery so awesome that, in practice, it doesn't matter?

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  • What are the interets of synthetic methods?

    - by romaintaz
    Problem One friend suggested an interesting problem. Given the following code: public class OuterClass { private String message = "Hello World"; private class InnerClass { private String getMessage() { return message; } } } From an external class, how may I print the message variable content? Of course, changing the accessibility of methods or fields is not allowed. (the source here, but it is a french blog) Solution The code to solve this problem is the following: try { Method m = OuterClass.class.getDeclaredMethod("access$000", OuterClass.class); OuterClass outerClass = new OuterClass(); System.out.println(m.invoke(outerClass, outerClass)); } catch (Exception e) { e.printStackTrace(); } Note that the access$000 method name is not really standard (even if this format is the one that is strongly recommanded), and some JVM will name this method access$0. Thus, a better solution is to check for synthetic methods: Method method = null; int i = 0; while ((method == null) && (i < OuterClass.class.getDeclaredMethods().length)) { if (OuterClass.class.getDeclaredMethods()[i].isSynthetic()) { method = OuterClass.class.getDeclaredMethods()[i]; } i++; } if (method != null) { try { System.out.println(method.invoke(null, new OuterClass())); } catch (Exception e) { e.printStackTrace(); } } So the interesting point in this problem is to highlight the use of synthetic methods. With these methods, I can access a private field as it was done in the solution. Of course, I need to use reflection, and I think that the use of this kind of thing can be quite dangerous... Question What is the interest - for me, as a developer - of a synthetic method? What can be a good situation where using the synthetic can be useful?

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  • Bootstrap stop Modal showing on page load

    - by Subby
    I only want the Modal to show when I click on a certain button. At the moment, the Modal shows itself whenever I load the page. Can someone please tell me where I am going horribly wrong? <a href="#myModal" role="button" class="btn" data-toggle="modal">Launch demo modal</a> <div class="modal" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button> <h3 id="myModalLabel">Modal header</h3> </div> <div class="modal-body"> <p>One fine body…</p> </div> <div class="modal-footer"> <button class="btn" data-dismiss="modal" aria-hidden="true">Close</button> <button class="btn btn-primary">Save changes</button> </div> </div> I am using ASP.NET MVC 3 EDIT: I am NOT using any Javascript at the moment.

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  • C++ CRTP question

    - by aaa
    following piece of code does not compile, the problem is in T::rank not be inaccessible (I think) or uninitialized in parent template. Can you tell me exactly what the problem is? is passing rank explicitly the only way? or is there a way to query tensor class directly? Thank you #include <boost/utility/enable_if.hpp> template<class T, // size_t N, class enable = void> struct tensor_operator; // template<class T, size_t N> template<class T> struct tensor_operator<T, typename boost::enable_if_c< T::rank == 4>::type > { tensor_operator(T &tensor) : tensor_(tensor) {} T& operator()(int i,int j,int k,int l) { return tensor_.layout.element_at(i, j, k, l); } T &tensor_; }; template<size_t N, typename T = double> // struct tensor : tensor_operator<tensor<N,T>, N> { struct tensor : tensor_operator<tensor<N,T> > { static const size_t rank = N; }; I know the workaround, however am interested in mechanics of template instantiation for self-education

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  • Create a simple automatic image switcher using jQuery

    - by Kim Andersen
    Hi all. I need to create a very simple image switcher that changes my images automatically. I have the following code: <div class="imgCarousel"> <div class="imgC1 left"><img src="/media/1614/1_1.jpg" alt="img1" /></div> <div class="imgC2 left"><img src="/media/1615/2_1.jpg" alt="img2" /></div> <div class="imgC3 left"><img src="/media/1616/3_1.gif" alt="img3" /></div> <div class="imgC4 left"><img src="/media/1617/4_1.jpg" alt="img4" /></div> <div class="imgC5 left"><img src="/media/1618/5_1.jpg" alt="img5a" /></div> <div class="imgC6 left"><img src="/media/1620/6_1.jpg" alt="img6a" /></div> <div class="imgC7 left"><img src="/media/1622/7.jpg" alt="img7" /></div> </div> Two of the above images should be switched automatically after a certain amount of time (every 3-4 sec.). This means that after 4 seconds, I'd like to change the image called /media/1618/5_1.jpg with another image. And after another 4 seconds, I'd switch back again. The same shold be made for one of my other images. How can I acomplish this with some jQuery?

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  • C++ Dynamic object construction

    - by Rajesh Subramanian
    I have a base class, class Msg { ParseMsg() { ParseMsgData(); ParseTrailer(); } virtual void ParseMsgData() = 0; ParseTrailer(); }; and derived classes, class InitiateMsg { void ParseMsgData() { ... } }; class ReadOperationMsg { void ParseMsgData() { ... } }; class WriteOperationMsg { void ParseMsgData() { ... } }; and the scenario is below, void UsageFunction(string data) { Msg* msg = ParseHeader(data); ParseMsg } Msg* ParseHeader(string data) { Msg *msg = NULL; .... switch() { case 1: msg = new InitiateMsg(); break; case 2: msg = new ReadOperationMsg{(); break; case 3: msg = new WriteOperationMsg{(); break; .... } return msg; } based on the data ParseHeader method will decide which object has to be created, So I have implemented ParseHeader function outside the class where I am using. How can I make the ParseHeader function inside the Msg class and then use it? In C# the same is achieved by defining ParseHeader method as static with in class and use it from outside,

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  • HTML Setting Active with different background colour

    - by danit
    Here is my HTML List: <ul id="navlist"> <li class="item1"><a href="#">One</a></li> <li class="item2"><a href="#">Two</a></li> <li class="item3"><a href="#">Three</a></li> <li class="item4"><a href="#">Four</a></li> <li class="item5"><a href="#">Five</a></li> <li class="item6"><a href="#">Six</a></li> </ul> Each .itemx has a different background colour, so I need the active state to take into account the class. Obviously something like: <li class="item6" id="active"><a href="#">Six</a></li> #active.item6 { background: red; } Would work but IE6 doesnt like chained items in CSS so doesnt work when other items are set out in the CSS. Can I do this with jQuery where each item has a different background colour when 'active?

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  • implementing the generic interface

    - by user845405
    Could any one help me on implementing the generic interface for this class. I want to be able to use the below Cache class methods through an interface. Thank you for the help!. public class CacheStore { private Dictionary<string, object> _cache; private object _sync; public CacheStore() { _cache = new Dictionary<string, object>(); _sync = new object(); } public bool Exists<T>(string key) where T : class { Type type = typeof(T); lock (_sync) { return _cache.ContainsKey(type.Name + key); } } public bool Exists<T>() where T : class { Type type = typeof(T); lock (_sync) { return _cache.ContainsKey(type.Name); } } public T Get<T>(string key) where T : class { Type type = typeof(T); lock (_sync) { if (_cache.ContainsKey(key + type.Name) == false) throw new ApplicationException(String.Format("An object with key '{0}' does not exists", key)); lock (_sync) { return (T)_cache[key + type.Name]; } } } public void Add<T>(string key, T value) { Type type = typeof(T); if (value.GetType() != type) throw new ApplicationException(String.Format("The type of value passed to cache {0} does not match the cache type {1} for key {2}", value.GetType().FullName, type.FullName, key)); lock (_sync) { if (_cache.ContainsKey(key + type.Name)) throw new ApplicationException(String.Format("An object with key '{0}' already exists", key)); lock (_sync) { _cache.Add(key + type.Name, value); } } } } Could any one help me on implementing the generic interface for this class. I want to be able to use the below Cache class methods through an interface.

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  • Project Naming Convention Feedback Please

    - by Sam Striano
    I am creating a ASP.NET MVC 3 application using Entity Framework 4. I am using the Repository/Service Pattern and was looking for feedback. I currently have the following: MVC Application (GTG.dll) GTG GTG.Controllers GTG.ViewModels Business POCO's (GTG.Business.dll) This contains all business objects (Customer, Order, Invoice, etc...) EF Model/Repositories (GTG.Data.dll) GTG.Business (GTG.Context.tt) I used the Entity POCO Generator Templates. GTG.Data.Repositories Service Layer (GTG.Data.Services.dll) GTG.Data.Services - Contains all of the service objects, one per aggregate root. The following is a little sample code: Controller Namespace Controllers Public Class HomeController Inherits System.Web.Mvc.Controller Function Index() As ActionResult Return View(New Models.HomeViewModel) End Function End Class End Namespace Model Namespace Models Public Class HomeViewModel Private _Service As CustomerService Public Property Customers As List(Of Customer) Public Sub New() _Service = New CustomerService _Customers = _Service.GetCustomersByBusinessName("Striano") End Sub End Class End Namespace Service Public Class CustomerService Private _Repository As ICustomerRepository Public Sub New() _Repository = New CustomerRepository End Sub Function GetCustomerByID(ByVal ID As Integer) As Customer Return _Repository.GetByID(ID) End Function Function GetCustomersByBusinessName(ByVal Name As String) As List(Of Customer) Return _Repository.Query(Function(x) x.CompanyName.StartsWith(Name)).ToList End Function End Class Repository Namespace Data.Repositories Public Class CustomerRepository Implements ICustomerRepository Public Sub Add(ByVal Entity As Business.Customer) Implements IRepository(Of Business.Customer).Add End Sub Public Sub Delete(ByVal Entity As Business.Customer) Implements IRepository(Of Business.Customer).Delete End Sub Public Function GetByID(ByVal ID As Integer) As Business.Customer Implements IRepository(Of Business.Customer).GetByID Using db As New GTGContainer Return db.Customers.FirstOrDefault(Function(x) x.ID = ID) End Using End Function Public Function Query(ByVal Predicate As System.Linq.Expressions.Expression(Of System.Func(Of Business.Customer, Boolean))) As System.Linq.IQueryable(Of Business.Customer) Implements IRepository(Of Business.Customer).Query Using db As New GTGContainer Return db.Customers.Where(Predicate) End Using End Function Public Sub Save(ByVal Entity As Business.Customer) Implements IRepository(Of Business.Customer).Save End Sub End Class End Namespace

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  • stdio data from write not making it into a file

    - by user1551209
    I'm having a problem with using stdio commands for manipulating data in a file. I short, when I write data into a file, write returns an int indicating that it was successful, but when I read it back out I only get the old data. Here's a stripped down version of the code: fd = open(filename,O_RDWR|O_APPEND); struct dE *cDE = malloc(sizeof(struct dE)); //Read present data printf("\nreading values at %d\n",off); printf("SeekStatus <%d>\n",lseek(fd,off,SEEK_SET)); printf("ReadStatus <%d>\n",read(fd,cDE,deSize)); printf("current Key/Data <%d/%s>\n",cDE->key,cDE->data); printf("\nwriting new values\n"); //Change the values locally cDE->key = //something new cDE->data = //something new //Write them back printf("SeekStatus <%d>\n",lseek(fd,off,SEEK_SET)); printf("WriteStatus <%d>\n",write(fd,cDE,deSize)); //Re-read to make sure that it got written back printf("\nre-reading values at %d\n",off); printf("SeekStatus <%d>\n",lseek(fd,off,SEEK_SET)); printf("ReadStatus <%d>\n",read(fd,cDE,deSize)); printf("current Key/Data <%d/%s>\n",cDE->key,cDE->data); Furthermore, here's the dE struct in case you're wondering: struct dE { int key; char data[DataSize]; }; This prints: reading values at 1072 SeekStatus <1072> ReadStatus <32> current Key/Data <27/old> writing new values SeekStatus <1072> WriteStatus <32> re-reading values at 1072 SeekStatus <1072> ReadStatus <32> current Key/Data <27/old>

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  • Looking for an appropriate design pattern

    - by user1066015
    I have a game that tracks user stats after every match, such as how far they travelled, how many times they attacked, how far they fell, etc, and my current implementations looks somewhat as follows (simplified version): Class Player{ int id; public Player(){ int id = Math.random()*100000; PlayerData.players.put(id,new PlayerData()); } public void jump(){ //Logic to make the user jump //... //call the playerManager PlayerManager.jump(this); } public void attack(Player target){ //logic to attack the player //... //call the player manager PlayerManager.attack(this,target); } } Class PlayerData{ public static HashMap<int, PlayerData> players = new HashMap<int,PlayerData>(); int id; int timesJumped; int timesAttacked; } public void incrementJumped(){ timesJumped++; } public void incrementAttacked(){ timesAttacked++; } } Class PlayerManager{ public static void jump(Player player){ players.get(player.getId()).incrementJumped(); } public void incrementAttacked(Player player, Player target){ players.get(player.getId()).incrementAttacked(); } } So I have a PlayerData class which holds all of the statistics, and brings it out of the player class because it isn't part of the player logic. Then I have PlayerManager, which would be on the server, and that controls the interactions between players (a lot of the logic that does that is excluded so I could keep this simple). I put the calls to the PlayerData class in the Manager class because sometimes you have to do certain checks between players, for instance if the attack actually hits, then you increment "attackHits". The main problem (in my opinion, correct me if I'm wrong) is that this is not very extensible. I will have to touch the PlayerData class if I want to keep track of a new stat, by adding methods and fields, and then I have to potentially add more methods to my PlayerManager, so it isn't very modulized. If there is an improvement to this that you would recommend, I would be very appreciative. Thanks.

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  • android: ending activity from tab

    - by Jin
    I have 3 classes, let's call them 1, 2, and 3. Class 1 extends TabActivity and organizes the whole tab thing, Class 2 and 3 are just two separate tabs each with some lines of text. I call Class 1 from another activity using startActivityForResult. I then added an optionsMenu in class 2, and when user clicks the optionMenu, the following code is carried out: @Override public boolean onMenuItemSelected(int featureId, MenuItem item) { Intent i = new Intent(); switch(item.getItemId()) { case Result.NEXT_ID: i.putExtra(Result.PAGE_REQUEST, NEXT); setResult(RESULT_OK, i); finish(); break; case Result.PREV_ID: i.putExtra(Result.PAGE_REQUEST, PREV); setResult(RESULT_OK, i); finish(); } return super.onMenuItemSelected(featureId, item); } In my parent class (the class that called 1 to begin with), in its onActivityResult function, I want to get the data from the extras. However, the intent is always null, and I can't figure out why. When I call finish() on class 2, is it calling some other function in class 1? Do I have to transfer the intent data somehow?

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  • javascript prototype problem

    - by Chris Tosswill
    So I have a rather basic javascript problem which I have been slamming my head into a wall over for awhile: <div class='alist'> <ul> <li class='group_1'> An Item </li> <li class='group_1'> An Item </li> <li class='group_2'> An Item </li> </ul> </div> <div class='alist'> <ul> <li class='group_1'> An Item </li> <li class='group_1'> An Item </li> <li class='group_2'> An Item </li> </ul> </div> <script> function toggle_item( num ){ $$( 'li.group_' + num ).invoke('toggle'); } </script> Basically, I need to create a sweeper that sets the div to display:none if all the li are display:none. I think it would start like: function sweep(){ $$('div.alist').each( function( s ) { ar = s.down().children }); } Any suggestions for good tutorials would be welcome as well

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