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  • Annotate and Aggregate function in django

    - by thesteve
    In django I have the following tables and am trying to count the number of votes by item. class Votes(models.Model): user = models.ForeignKey(User) item = models.ForeignKey(Item) class Item(models.Model): name = models.CharField() description = models.TextField() I have the following queryset queryset = Votes.objects.values('item__name').annotate(Count('item')) that returns a list with item name and view count but not the item object. How can I set it up so that the object is returned instead of just the string value? I have been messing around with Manager and Queryset methods, that the right track? Any advice would be appreciated.

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  • What's a good tutorial for creating a gem with RSpec?

    - by ramon.tayag
    I've been searching around for ways to create a gem with RSpec, but haven't found descriptive tutorials. I started out with Ryan Bates' Making a gem, but I'm looking for a tutorial that discusses creating an acts_as style gem with RSpec. By acts_as, I mean to say that the gem adds certain methods to an existing class in Rails. Why is this important? Because I've found gem templates like New Gem, got a spec to run but when I try to test an Active Record object it starts choking. I've tried requiring active_record in spec_helper.rb but I must be doing something wrong because it doesn't solve the problem. When it comes to plugins, I found this Rails Guide. If there's a gem version for that around that'd be awesome. Thanks guys! P.S. I love screencasts.

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  • Whats the significance of named scope in rails?

    - by piemesons
    Before going for details. Question 1:-- Whats the meaning of scope here (ie named scope)? whats the benefits of using named scope? Now:- from agile development with rails book:-- class Order < ActiveRecord::Base named_scope :last_n_days, lambda { |days| {:conditions => ['updated < ?' , days] } } named_scope :checks, :conditions => {:pay_type => :check} end Such a named scope would make finding the last weeks worth of orders a snap. orders = Orders.last_n_days(7) Scopes can also be combined orders = Orders.checks.last_n_days(7) why we are using named_scope here. We can do the same using methods. Whats special thing we got using named_scope.

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  • Copy Structure To Another Program

    - by Steven
    Long story, long: I am adding a web interface (ASPX.NET: VB) to a data acquisition system developed with LabVIEW which outputs raw data files. These raw data files are the binary representation of a LabVIEW cluster (essentially a structure). LabVIEW provides functions to instantiate a class or structure or call a method defined in a .NET DLL file. I plan to create a DLL file containing a structure definition and a class with methods to transfer the structure. When the webpage requests data, it would call a LabVIEW executable with a filename parameter. The LabVIEW code would instantiate the structure, populate the structure from the data file, then call the method to transfer the data back to the website. Long story, short: How do you recommend I transfer (copy) an instance of a structure from one .NET program to a VB.NET program? Ideas considered: sockets, temp file, xml file, config file, web services, CSV, some type of serialization, shared memory

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  • Java: design problem with final-value and empty constructor

    - by HH
    $ javac InitInt.java InitInt.java:7: variable right might not have been initialized InitInt(){} ^ 1 error $ cat InitInt.java import java.util.*; import java.io.*; public class InitInt { private final int right; // Design Problem? // I feel the initialization problem is just due to bad style. InitInt(){} InitInt{ // Still the error, "may not be initialized" // How to initialise it? if(snippetBuilder.length()>(charwisePos+25)){ right=charwisePos+25; }else{ right=snippetBuilder.length()-1; } } public static void main(String[] args) { InitInt test = new InitInt(); System.out.println(test.getRight()); } public int getRight(){return right;} } Partial Solutions and Suggestions use "this" to access methods in the class, instead of creating empty constructor change final to non-final with final field value: initialize all final values in every constructor remove the empty constructor, keep your code simple and clean

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  • Why is IHttpAsyncHandler being called over IHttpHandler?

    - by Tim Hardy
    I made a custom handler that derives from MvcHandler. I have my routes using a custom RouteHandler that returns my new handler for GetHttpHandler(), and I override ProcessRequest() in my custom handler. The call to GetHttpHandler is triggering a breakpoint and my handler's constructor is definitely being called, but BeginProcessRequest() is being called on the base MvcHandler instead of ProcessRequest(). Why are the async methods being called when I haven't done anything to call them? I don't want asynchronous handling, and I certainly didn't do anything explicit to get it. My controllers all derive from Controller, not AsyncController. I don't have the source code with me right now, but I can add it later if needed. I was hoping someone might know some of the reasons why BeginProcessRequest might be called when it's not wanted.

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  • http(/* argument here */) How is this Object (Http) being used without an explicit or implicit meth

    - by Randin
    In the example for coding with Json using Databinder Dispatch Nathan uses an Object (Http) without a method, shown here: import dispatch._ import Http._ Http("http://www.fox.com/dollhouse/" >>> System.out ) How is he doing this? Thank you for all of the answers unfortunatly I was not specific enough... It looks like it is simply passing an argument to a constructor of class or companion object Http. In another example, I've seen another form: http = new Http http(/* argument here */) Is this valid Scala? I guess it must be, because the author is a Scala expert. But it makes no sense to me. Actions are usually performed by invoking methods on objects, whether explicitly as object.doSomething() or implicitly as object = something (using the apply() method underneath the syntactic sugar). All I can think of is that a constructor is being used to do something in addition to constructing an object. In other words, it is having side effects, such as in this case going off and doing something on the web.

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  • How do I Call a method from other Class

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

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  • Is yield break equivalent to returning Enumerable<T>.Empty from a method returning IEnumerable<T>

    - by Mike Two
    These two methods appear to behave the same to me public IEnumerable<string> GetNothing() { return Enumerable.Empty<string>(); } public IEnumerable<string> GetLessThanNothing() { yield break; } I've profiled each in test scenarios and I don't see a meaningful difference in speed, but the yield break version is slightly faster. Are there any reasons to use one over the other? Is one easier to read than the other? Is there a behavior difference that would matter to a caller?

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  • static void classes

    - by ivor
    Hello, I'm tidying up some of my code with the correct scope on some methods and attributes (I have two classes and at the moment I have a number which I just declared as public to get working, but I feel I should look into this and make private where possible, for better practice) When working in eclipse it's suggested on one method, when i change it private from public, that I can fix it by dropping off the scope so the method just says "static void" instead of public/private static void. Is this a better scenario to have nothing, rather than private or public - or is the default scope equivelant to public anyway ? Thanks

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  • NSThread vs. NSOperationQueue vs. ??? on the iPhone

    - by kubi
    Currently I'm using NSThread to cache images in another thread. [NSThread detachNewThreadSelector:@selector(cacheImage:) toTarget:self withObject:image]; Alternatively: [self performSelectorInBackground:@selector(cacheImage:) withObject:image]; Alternatively, I can use an NSOperationQueue NSInvocationOperation *invOperation = [[NSInvocationOperation alloc] initWithTarget:self selector:@selector(cacheImage:) object:image]; NSOperationQueue *opQueue = [[NSOperationQueue alloc] init]; [opQueue addOperation:invOperation]; Is there any reason to switch away from NSThread? GCD is a 4th option when it's released for the iPhone, but unless there's a significant performance gain, I'd rather stick with methods that work in most platforms.

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  • C++/CLI .ToString() returning error

    - by George Johnston
    I am a beginner to C++/CLI as I come from a C# background. I am currently writing a wrapper for some native C++ code. I have the following methods: void AddToBlockList(System::String^ address) { char* cAddress = (char*)(void*)Marshal::StringToHGlobalAnsi(address); _packetFilter->AddToBlockList(cAddress); } void AddToBlockList(IPAddress^ address) { char* cAddress = (char*)(void*)Marshal::StringToHGlobalAnsi(address.ToString()); _packetFilter->AddToBlockList(cAddress); } ...The first method works fine and converts my string into the character array. However, the second function with the IPAddress object as the signiture gives me the following error: error C2228: left of '.ToString' must have class/struct/union ...When I type ? address.ToString() ...in the command window, the IP Address prints. Not sure where I'm going wrong. Any ideas?

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  • Implementing a Stack using Test-Driven Development

    - by devoured elysium
    I am doing my first steps with TDD. The problem is (as probably with everyone starting with TDD), I never know very well what kind of unit tests to do when I start working in my projects. Let's assume I want to write a Stack class with the following methods(I choose it as it's an easy example): Stack<T> - Push(element : T) - Pop() : T - Seek() : T - Count : int - IsEmpty : boolean How would you approch this? I never understood if the idea is to test a few corner cases for each method of the Stack class or start by doing a few "use cases" with the class, like adding 10 elements and removing them. What is the idea? To make code that uses the Stack as close as possible to what I'll use in my real code? Or just make simple "add one element" unit tests where I test if IsEmpty and Count were changed by adding that element? How am I supposed to start with this?

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  • Add columns to SqlWebEventProvider

    - by Julien N
    In an asp.net application, we'd like to use the SqlWebEventProvider to log any Event that occurs during the application lifetime. The problem is that we think that the table aspnet_WebEvent_Event doesn't provide enough columns and should log more information (we need to keep the Logged user). I'm aware that this information could be stored in the "Details" column but it wouldn't then be really simple to filter the results and build reports. So I'm searching for a simple solution to add a column. I wish I could derive SqlWebEventProvider but the methods used to build the stocked procedure parameters are private (PrepareParams() and FillParams()). Any simple solution that doesn't imply to rewrite the entire Provider class ?

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  • distance between two points across land using sql server

    - by dpwb
    I am looking to calculate the shortest distance between two points inside SQL Server 2008 taking into account land mass only. I have used the geography data type along with STDistance() to work out point x distance to point y as the crow flies, however this sometimes crosses the sea which i am trying to avoid. I have also created a polygon around the land mass boundary I am interested in. I believe that I need to combine these two methods to ensure that STDistance always remains within polygon - unless there is a simpler solution. Thanks for any advice

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  • Like Html.RenderAction() but without reinstantiating the controller object

    - by Jørn Schou-Rode
    I like to use the RenderAction extension method on the HtmlHelper object to render sidebars and the like in pages, as it allows me to keep the data access code for each such part in separate methods on the controller. Using an abstract controller base, I can define a default "sidebar strategy", which can then be refined by overriding the method in a concrete controller, when needed. The only "problem" I have with this approach, is that the RenderAction is built in a way where it always creates a news instance of the controller class, even when rendering actions from the controller already in action. Some of my controllers does some data lookup in their Initialize method, and using the RenderAction method in the view causes this to occur several times in the same request. Is there some alternative to RenderAction which will reuse the controller object if the action method to be invoked is on the same controller class as the "parent" action?

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  • asp.net - csharp - jquery - looking for a better and usage solution

    - by LostLord
    hi my dear friends i have a little problem about using jquery...(i reeally do not know jquery but i forced to use it) i am using vs 2008 - asp.net web app with c# also i am using telerik controls in my pages also i am using sqldatasources (Connecting to storedprocedures) in my pages my pages base on master and content pages and in content pages i have mutiviews ================================================================================= in one of the views(inside one of those multiviews)i had made two radcombo boxes for country and city requirement like cascading dropdowns as parent and child combo boxes. i used old way for doing that , i mean i used update panel and in the SelectedIndexChange Event of Parent RadComboBox(Country) i Wrote this code : protected void RadcomboboxCountry_SelectedIndexChanged(object o, RadComboBoxSelectedIndexChangedEventArgs e) { hfSelectedCo_ID.Value = RadcomboboxCountry.SelectedValue; RadcomboboxCity.Items.Clear(); RadcomboboxCity.Items.Add(new RadComboBoxItem(" ...", "5")); RadcomboboxCity.DataBind(); RadcomboboxCity.SelectedIndex = 0; } my child radcombo box can fill by upper code , let me tell you how : the child sqldatasource have a sp that has a parameter and i fill that parameter by this line - hfSelectedCo_ID.Value = RadcbCoNameInInsert.SelectedValue; RadcbCoNameInInsert.SelectedValue means country ID. after doing that SelectedIndexChange Event of Parent RadComboBox(Country) could not be fire therefore i forced to set the autopostback property to true. afetr doing that every thing was ok until some one told me can u control focus and keydown of your radcombo boxes (when u press enter key on the parent combobox[country] , so child combobox gets focus -- and when u press upperkey on child radcombobox [city], so parent combobox[country] gets focus) (For Users That Do Not Want To Use Mouse for Input Info And Choose items) i told him this is web app , not win form and we can not do that. i googled it and i found jquery the only way for doing that ... so i started using jquery . i wrote this code with jquery for both of them : <script src="../JQuery/jquery-1.4.1.js" language="javascript" type="text/javascript"></script> <script type="text/javascript"> $(function() { $('input[id$=RadcomboboxCountry_Input]').focus(); $('input[id$=RadcomboboxCountry_Input]').select(); $('input[id$=RadcomboboxCountry_Input]').bind('keyup', function(e) { var code = (e.keyCode ? e.keyCode : e.which); if (code == 13) { -----------> Enter Key $('input[id$=RadcomboboxCity_Input]').focus(); $('input[id$=RadcomboboxCity_Input]').select(); } }); $('input[id$=RadcomboboxCity_Input]').bind('keyup', function(e) { var code = (e.keyCode ? e.keyCode : e.which); if (code == 38) { -----------> Upper Key $('input[id$=RadcomboboxCountry_Input]').focus(); $('input[id$=RadcomboboxCountry_Input]').select(); } }); }); </script> this jquery code worked BBBBBBUUUUUUUTTTTTT autopostback=true of the Parent RadComboBox Became A Problem , Because when SelectedIndex Change Of ParentRadComboBox is fired after that Telerik Skins runs and after that i lost parent ComboBox Focus and we should use mouse but we don't want it.... for fix this problem i decided to set autopostback of perentCB to false and convert protected void RadcomboboxCountry_SelectedIndexChanged(object o, RadComboBoxSelectedIndexChangedEventArgs e) { hfSelectedCo_ID.Value = RadcomboboxCountry.SelectedValue; RadcomboboxCity.Items.Clear(); RadcomboboxCity.Items.Add(new RadComboBoxItem(" ...", "5")); RadcomboboxCity.DataBind(); RadcomboboxCity.SelectedIndex = 0; } to a public non static method without parameters and call it with jquey like this : (i used onclientchanged property of parentcombo box like onclientchanged = "MyMethodForParentCB_InJquery();" insread of selectedindexchange event) public void MyMethodForParentCB_InCodeBehind() { hfSelectedCo_ID.Value = RadcomboboxCountry.SelectedValue; RadcomboboxCity.Items.Clear(); RadcomboboxCity.Items.Add(new RadComboBoxItem(" ...", "5")); RadcomboboxCity.DataBind(); RadcomboboxCity.SelectedIndex = 0; } for doing that i read the blow manual and do that step by step : ======================================================================= http://www.ajaxprojects.com/ajax/tutorialdetails.php?itemid=732 ======================================================================= but this manual is about static methods and this is my new problem ... when i am using static method like : public static void MyMethodForParentCB_InCodeBehind() { hfSelectedCo_ID.Value = RadcomboboxCountry.SelectedValue; RadcomboboxCity.Items.Clear(); RadcomboboxCity.Items.Add(new RadComboBoxItem(" ...", "5")); RadcomboboxCity.DataBind(); RadcomboboxCity.SelectedIndex = 0; } so i recieved some errors and this method could not recognize my controls and hidden field... one of those errors like this : Error 2 An object reference is required for the non-static field, method, or property 'Darman.SuperAdmin.Users.hfSelectedCo_ID' C:\Javad\Copy of Darman 6\Darman\SuperAdmin\Users.aspx.cs 231 13 Darman any idea or is there any way to call non static methods with jquery (i know we can not do that but is there another way to solve my problem)???????????????

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  • Image Uploading - security issues

    - by TenaciousImpy
    Hi, I'm developing an ASP.NET Web app and would like the user to be able to either upload an image from their local system, or pass in a URL to an image. The image can either be a JPG or PNG. What security issues should I be concerned about doing this? I've seen various ways of embedding code within JPG files. Are there any methods in C# (or external libraries) which can confirm that a file is a JPG/PNG, otherwise throw an error? At the very least, I'm making the directory which holds uploaded images non-browsable and putting a max size limit of 1mb, but I'd like to implement further checks. Thanks for any advice.

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  • C# Operator Overloading post-fix increment

    - by Victor
    I'm coding a date class and am having trouble with the post-fix increment (the prefix increment seems fine). Here is the sample code: public class date { int year, month, day; public date(int d, int m, int y) { day = d; month = m; year = y; } static public date operator ++(date d) { return d.Next(d); } } The method "Next(date d)" takes a date and returns tomorrows date (I left it out for brevity). I'm to young in C# to understand why the prefix is fine but postfix increment does nothing. But remember in C++ we would have to have two methods instead of just one - for prefix and postfix increments. Also no errors or warnings on compile.

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  • Out of Memory When Loading Java Entities

    - by Hugh Buchanan
    I have a terrible problem that hopefully has a very simple answer. I am running out of memory when I perform a basic If I have code like this: MyEntity myEntity; for (Object id: someIdList) { myEntity = find(id); // do something basic with myEntity } And the find() method is a standard EntityManager related method: public MyEntity find(Object id) { return em.find(mycorp.ejb.entity.MyEntity.class, id); } This code worked a couple of weeks ago, and works fine if there are fewer items in the database. The resulting error I am facing is: java.lang.OutOfMemoryError: GC overhead limit exceeded The exception is coming from oracle toplink calling some oracle jdbc methods. The loop exists because an EJBQL such as "select object(o) from MyEntity as o" will overload the application server when there are lots of records.

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  • Devise within namespace

    - by Harm de Wit
    Hey, I'm trying to split my rails project in a front-end for regular users and a back-end for admins. Therefore i have created a namespace 'admin' so that i can easily control admin specific controller methods/layouts/authentication in the map admin. I'm using Devise to register/authenticate my admins only. Because it is only used for admins only i'm trying to move Devise to the admin namespace. I could not find exactly what i was looking for in the documentation of Devise but i tried something like this in routes.rb: namespace 'admin'do devise_for :admins end I also tried to make a custom Devise::Sessions controller but that too didn't seem to work out. Does anyone know how to do this? Should i just use the regular routes for devise with a custom(admin) layout?

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  • asp.net mvc 2: SportsStore application: The current request for action is ambiguous

    - by dotnet-practitioner
    I am working on SportsStore example on chapter 4 from the following book and getting stuck... Pro Asp.net mvc framework I get the following error: The current request for action 'List' on controller type 'ProductsController' is ambiguous between the following action methods: System.Web.Mvc.ViewResult List() on type WebUI.Controllers.ProductsController System.Web.Mvc.ViewResult List(Int32) on type WebUI.Controllers.ProductsController .. My router code looks as follows: public static void RegisterRoutes(RouteCollection routes) { routes.MapRoute( null, // Route name "", // URL with parameters new { controller = "Products", action = "List", page=1 } ); routes.MapRoute( null, // Route name "Page{page}", // URL with parameters new { controller = "Products", action = "List" }, // Parameter defaults new { page = @"\d+" } ); } and controller code looks as follows: public ViewResult List() { return View(productsRepository.Products.ToList()); } public ViewResult List(int page) { return View(productsRepository.Products .Skip((page - 1) * PageSize) .Take(PageSize) .ToList()); } What am I missing? my url is as follows: http://localhost:1103/ or http://localhost:1103/Page1 or http://localhost:1103/Page2 thanks

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  • getting the name of the calling method

    - by zeocrash
    Basically i've got a web service that i'm trying to put some kind of usage logging in. To do this i've created a class with a logging method. I instatiate the class on the service and then call the logging method in each of the web methods. I'm trying to find a way of getting the name of the method that has called the loggong method Public sub tstmethod log_object.log_method end sub in this case the returned name i'm looking for is "tstmethod" Everywhere i've seen has said to either use Dim stackframe As New Diagnostics.StackFrame Return stackframe.GetMethod.Name.ToString Or to use Dim stackframe As New Diagnostics.StackFrame Return stackframe.GetMethod.DeclaringType.FullName which i call inside the logging method getmethod.name.tostring returns the name of the logging method getmethod.declaringtype.fullname returns the name of the logging class no matter what i do i cannot find a way of getting the name of the method that called the logging method in this case "tstmethod"

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  • UITableView's cellForRowAtIndexPath is not getting called after low memory warning

    - by Jinesh
    I am new to COCOA and Objective C. I am working on an application which have two controllers with one table view in each, clicking an item form this table will lead to another controller to be pushed to the stack. All was working fine till i started handling low memory warning in app delegate. What i am doing in app delegate's applicationDidReceiveMemoryWarning is, deleting all of my model and popping out all controllers to its root view using popToRootViewControllerAnimated. Now my problem starts, once low mem warning is received table's cellForRowAtIndexPath is not getting called. All other methods of UITableViewDataSource is properly called. What i get on screen is a blank white screen. I am testing my app in iPhone OS 3.0 and development is done in Xcode V 3.1.3. Hope you guys can help me to nail this. Thanks in advance, Jinesh.

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  • Inheriting from class that inherits from DynamicObject

    - by SeveQ
    Hello there, I'm experimenting with C# 4.0's dynamic object model. I've created an abstract class named "Block" that inherits from DynamicObject. It overrides TryGetMember and TrySetMember. Furthermore I've created a usable class named "Brush" that inherits from "Block". I want it to be usable dynamically. But when I create a dynamic object from it and try to access a runtime bound member, it pelts me with an exception telling me that the member doesn't exist. The overridden TryGetMember or TrySetMember methods of the abstract parent class aren't getting called. Is this behaviour to be expected? Thank you!

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