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  • ASP.Net MVC Object Reference in Edit View when using DropDownListFor()

    - by hermiod
    This question is related to another I ask recently, it can be found here for some background information. Here is the code in the Edit ActionResult: public virtual ActionResult Edit(int id) { ///Set data for DropDownLists. ViewData["MethodList"] = tr.ListMethods(); ViewData["GenderList"] = tr.ListGenders(); ViewData["FocusAreaList"] = tr.ListFocusAreas(); ViewData["SiteList"] = tr.ListSites(); ViewData["TypeList"] = tr.ListTalkbackTypes(); ViewData["CategoryList"] = tr.ListCategories(); return View(tr.GetTalkback(id)); } I add lists to the ViewData to use in the dropdownlists, these are all IEnumerable and are all returning values. GetTalkback() returns an Entity framework object of type Talkback which is generated from the Talkback table. The DropDownListFor code is: <%: Html.DropDownListFor(model=>model.method_id,new SelectList(ViewData["MethodList"] as IEnumerable<SelectListItem>,"Value","Text",Model.method_id)) %> The record I am viewing has values in all fields. When I click submit on the View, I get an Object reference not set to an instance of an object. error on the above line. There are a number of standard fields in the form prior to this, so the error is only occurring on dropdown lists, and it is occurring on all of them. Any ideas? This is my first foray in to MVC, C#, and Entity so I am completely lost!

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  • IoC - Dynamic Composition of object instances

    - by Joshua Starner
    Is there a way using IoC, MEF [Imports], or another DI solution to compose dependencies on the fly at object creation time instead of during composition time? Here's my current thought. If you have an instance of an object that raises events, but you are not creating the object once and saving it in memory, you have to register the event handlers every time the object is created. As far as I can tell, most IoC containers require you to register all of the classes used in composition and call Compose() to make it hook up all the dependencies. I think this may be horrible design (I'm dealing with a legacy system here) to do this due to the overhead of object creation, dependency injection, etc... but I was wondering if it was possible using one of the emergent IoC technologies. Maybe I have some terminology mixed up, but my goal is to avoid writing a framework to "hook up all the events" on an instance of an object, and use something like MEF to [Export] handlers (dependencies) that adhere to a very specific interface and [ImportMany] them into an object instance so my exports get called if the assemblies are there when the application starts. So maybe all of the objects could still be composed when the application starts, but I want the system to find and call all of them as the object is created and destroyed.

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  • Two Way Data Binding With a Object in WPF,Image Control

    - by Candy
    Sorry, my English is not very good, I have a object "Stuffs" "Stuffs" have a Property “Icon” now: xaml <Button Click="Button_Click"><Image Width="80" Height="80" Source="{Binding Path=Icon,Converter={StaticResource ImageConverter}}"/></Button> cs private void Button_Click(object sender, RoutedEventArgs e) { IconFloder.Title = "Icon"; String IconFloderPath = AppDomain.CurrentDomain.BaseDirectory + ItemIconFloder; if (!System.IO.Directory.Exists(IconFloderPath)) System.IO.Directory.CreateDirectory(IconFloderPath); IconFloder.InitialDirectory = IconFloderPath; IconFloder.Filter = "Image File|*.jpeg"; IconFloder.ValidateNames = true; IconFloder.CheckPathExists = true; IconFloder.CheckFileExists = true; if (IconFloder.ShowDialog() == true) { HideImage.Text = ItemIconFloder + "\\" + IconFloder.SafeFileName; ((sender as Button).Content as Image).Source = new ImageConverter().Convert(ItemIconFloder + "\\" + IconFloder.SafeFileName, Type.GetType("System.Windows.Media.ImageSource"), null, new System.Globalization.CultureInfo("en-US")) as ImageSource; } } class ImageConverter:IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { if (value is string&&!String.IsNullOrEmpty(value.ToString())) { try { return new BitmapImage(new Uri(AppDomain.CurrentDomain.BaseDirectory + value)); } catch { } } return null; } public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) { throw new NotImplementedException(); } } I would like to click buttons, change the picture, Also change Data Binding Stuffs.Icon But failed,I have no idea?I need help? I do not know whether I speak clearly

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  • WPF - How to properly reference a class from XAML

    - by Andy T
    OK, this is a super super noob question, one that I'm almost embarrassed to ask... I want to reference a class in my XAML file. It's a DataTemplateSelector for selecting the right edit template for a DataGrid column. Anyway, I've written the class into my code behind, added the local namespace to the top of top of the XAML, but when I try to reference the class from the XAML, it tells me the class does not exist in the local namespace. I must be missing something really really simple but I just can't understand it... Here's my code. XAML: <Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:tk="http://schemas.microsoft.com/wpf/2008/toolkit" xmlns:local="clr-namespace:CustomFields" xmlns:col="clr-namespace:System.Collections;assembly=mscorlib" xmlns:sys="clr-namespace:System;assembly=mscorlib" x:Class="CustomFields.MainWindow" x:Name="Window" Title="Define Custom Fields" Width="425" Height="400" MinWidth="425" MinHeight="400"> <Window.Resources> <ResourceDictionary> <local:RangeValuesEditTemplateSelector> blah blah blah... </local:RangeValuesEditTemplateSelector> </ResourceDictionary> </Window.Resources> C#: namespace CustomFields { /// /// Interaction logic for MainWindow.xaml /// public partial class MainWindow : Window { public MainWindow() { this.InitializeComponent(); // Insert code required on object creation below this point. } } public class RangeValuesEditTemplateSelector : DataTemplateSelector { public RangeValuesEditTemplateSelector(){ MessageBox.Show("hello"); } } } Any ideas what I'm doing wrong? I thought this should be simple as 1-2-3... Thanks! AT

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  • python: how to design a container with elements that must reference their container

    - by Luke404
    (the title is admittedly not that great. Please forgive my English, this is the best I could think of) I'm writing a python script that will manage email domains and their accounts, and I'm also a newby at OOP design. My two (related?) issues are: the Domain class must do special work to add and remove accounts, like adding/removing them to the underlying implementation how to manage operations on accounts that must go through their container To solve the former issue I'd add a factory method to the Domain class that'll build an Account instance in that domain, and a 'remove' (anti-factory?) method to handle deletions. For the latter this seems to me "anti-oop" since what would logically be an operation on an Account (eg, change password) must always reference the containing Domain. Seems to me that I must add to the Account a reference back to the Domain and use that to get data (like the domain name) or call methods on the Domain class. Code example (element uses data from the container) that manages an underlying Vpopmail system: class Account: def __init__(self, name, password, domain): self.name = name self.password = password self.domain = domain def set_password(self, password): os.system('vpasswd %s@%s %s' % (self.name, self.domain.name, password) self.password = password class Domain: def __init__(self, domain_name): self.name = domain_name self.accounts = {} def create_account(self, name, password): os.system('vadduser %s@%s %s' % (name, self.name, password)) account = Account(name, password, self) self.accounts[name] = account def delete_account(self, name): os.system('vdeluser %s@%s' % (name, self.name)) del self.accounts[name] another option would be for Account.set_password to call a Domain method that would do the actual work - sounds equally ugly to me. Also note the duplication of data (account name also as dict key), it sounds logical (account names are "primary key" inside a domain) but accounts need to know their own name.

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  • C#/Java: Proper Implementation of CompareTo when Equals tests reference identity

    - by Paul A Jungwirth
    I believe this question applies equally well to C# as to Java, because both require that {c,C}ompareTo be consistent with {e,E}quals: Suppose I want my equals() method to be the same as a reference check, i.e.: public bool equals(Object o) { return this == o; } In that case, how do I implement compareTo(Object o) (or its generic equivalent)? Part of it is easy, but I'm not sure about the other part: public int compareTo(Object o) { if (! (o instanceof MyClass)) return false; MyClass other = (MyClass)o; if (this == other) { return 0; } else { int c = foo.CompareTo(other.foo) if (c == 0) { // what here? } else { return c; } } } I can't just blindly return 1 or -1, because the solution should adhere to the normal requirements of compareTo. I can check all the instance fields, but if they are all equal, I'd still like compareTo to return a value other than 0. It should be true that a.compareTo(b) == -(b.compareTo(a)), and the ordering should stay consistent as long as the objects' state doesn't change. I don't care about ordering across invocations of the virtual machine, however. This makes me think that I could use something like memory address, if I could get at it. Then again, maybe that won't work, because the Garbage Collector could decide to move my objects around. hashCode is another idea, but I'd like something that will be always unique, not just mostly unique. Any ideas?

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  • TypeError: Error #1009 - (Null reference error) With Flash.

    - by Wind Chimez
    I am not an expert in flash, but i do work with AS and tweak Flash projects , though not having deep expertise in it. Currently i need to revamp a flash website done by one another guy, and the code base given to me, upon execution is throwing the following error. "--- TypeError: Error #1009: Cannot access a property or method of a null object reference. at NewSite_fla::MainTimeline/__setProp_ContactOutP1_ContactOut_Contents_0() at NewSite_fla::MainTimeline/frame1() --" The structure of the project is like, it has the different sections split into different movie clips. There is no single main timeline, but click actions on different areas of seperate movie clips will take them between one another. All the AS logic of event handling are written inline in FLA , no seperate Document class exists. Preloader Movie clip is the first one getting loaded. As i understood the error is getting thrown initially itself, and it is not happening due to any Action script logic written inline, because it is throwing error even before hitting the first inline AS code. I am not able to figure Out what exactly it causing the problem, or where to resolve it. I setup the stuff online, for reference if anybody want to take a look at it, and here is the link.You need to have flash debugger turned ON in your browser, if need to see the exception getting triggered. http://tinyurl.com/2alvlfx I really got stuck at this point. Any help will be great.I had not seen the particular solution i am looking for anywhere yet, though Error #1009 is common.

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  • Rhino Commons and Rhino Mocks Reference Documents?

    - by Ogre Psalm33
    Ok, is it just me, or does there seem to be a lack of (easy to find) reference documentation for Rhino Commons and Rhino Mocks? My coworkers have started using Rhino Mocks and Rhino Commons (particularly the NHibernate stuff), and I found a few tutorial-ish examples, which were good. But when I see them making use of a class in their code--let's pick something like Rhino.Commons.NHRepository, for example--I have been having a hard time just finding someplace on the web that tells me what Rhino.Commons.NHRepository is or what it does. I like to learn by looking at real examples, but using this approach, it's very handy to look at what the full docs are for a class, instead of just the current context. Similarly, I saw IaMockedRepository.Expect(...) being used in some code, but it took me forever to finally find this page that explains the AAA syntax for Rhino Mocks, which made it clear to me. I've found the Ayende.com wiki on Rhino Commons, but that seems to have a number of broken links. To me, the Rhino libraries seem like a great set of libraries in need of some desperate community help in the documentation area (Of course, as we all know, documentation is not the forte of most coders, and incomplete docs are all too common). Does anyone know if this is something in the works, someplace that some volunteer documenters are needed, or is there some great reference docs out there that I have somehow missed to Rhino Mocks and Rhino Commons?

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  • TypeError: Error #1009 - (Null reference error) With Flash.

    - by Wind Chimez
    I am not an expert in flash, but i do work with AS and tweak Flash projects , though not having deep expertise in it. Currently i need to revamp a flash website done by one another guy, and the code base given to me, upon execution is throwing the following error. "--- TypeError: Error #1009: Cannot access a property or method of a null object reference. at NewSite_fla::MainTimeline/__setProp_ContactOutP1_ContactOut_Contents_0() at NewSite_fla::MainTimeline/frame1() --" The structure of the project is like, it has the different sections split into different movie clips. There is no single main timeline, but click actions on different areas of seperate movie clips will take them between one another. All the AS logic of event handling are written inline in FLA , no seperate Document class exists. Preloader Movie clip is the first one getting loaded. As i understood the error is getting thrown initially itself, and it is not happening due to any Action script logic written inline, because it is throwing error even before hitting the first inline AS code. I am not able to figure Out what exactly it causing the problem, or where to resolve it. I really got stuck at this point. Any help will be great.I had not seen the particular solution i am looking for anywhere yet, though Error #1009 is common. I uploaded the fla, here ( http://tinyurl.com/249e95p ), for reference.It may not be working , since the included/refered video files and all are not there, but reviwing the action code/movie clips will be possible. Please let me know if somebody will be able to trace the issue exactly.

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  • Why can't I build this Javascript object?

    - by Alex Mcp
    I have an object I'm trying to populate from another object (that is, iterate over a return object to produce an object with only selected values from the original). My code looks like this: var collect = {}; function getHistoricalData(username){ $.getJSON("http://url/" + username + ".json?params", function(data){ for (var i=0; i < data.length; i++) { console.log(i); collect = { i : {text : data[i].text}}; $("#wrap").append("<span>" + data[i].text + "</span><br />"); }; console.log(collect); }); } So I'm using Firebug for debugging, and here's what I know: The JSON object is intact console.log(i); is showing the numbers 1-20 as expected When I log the collect object at the end, it's structure is this: var collect = { i : {text : "the last iteration's text"}}; So the incrementer is "applying" to the data[i].text and returning the text value, but it's not doing what I expected, which is create a new member of the collect object; it's just overwriting collect.i 20 times and leaving me with the last value. Is there a different syntax I need to be using for assigning object members? I tried collect.i.text = and collect[i].text = and the error was that whatever I tried was undefined. I'd love to know what's going on here, so the more in-depth an explanation the better. Thanks!

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  • Why "Not an ARRAY reference" error?

    - by Sandra Schlichting
    I have this script #!/usr/bin/perl use strict; use warnings; use yy; my $data = [ ["aax", "ert", "ddd"], ["asx", "eer", "kkk"], ["xkk", "fff", "lll"], ["xxj", "vtt", "lle"], ]; use Test::More tests => 4; is(yy::type1_to_type2(\$data, 'aax'), 'ert'); is(yy::type1_to_type3(\$data, 'asx'), 'kkk'); is(yy::type2_to_type3(\$data, 'fff'), 'lll'); is(yy::type3_to_type1(\$data, 'lle'), 'xxj'); which uses this module package yy; sub typeX_to_typeY { my ($x, $y, $data, $str) = @_; foreach (@$data) { if ($_->[$x - 1] eq $str) { return $_->[$y - 1]; } } return; } sub type1_to_type2 { typeX_to_typeY(1, 2, @_) } sub type1_to_type3 { typeX_to_typeY(1, 3, @_) } sub type2_to_type1 { typeX_to_typeY(2, 1, @_) } sub type2_to_type3 { typeX_to_typeY(2, 3, @_) } sub type3_to_type1 { typeX_to_typeY(3, 1, @_) } sub type3_to_type2 { typeX_to_typeY(3, 2, @_) } 1; and gives this error Not an ARRAY reference at yy.pm line 6. # Looks like your test died before it could output anything. The line it complains about is foreach (@$data) { Isn't this the way to pass an array reference? What am I doing wrong?

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  • Object addSubview only works in viewDidLoad

    - by DecodingSand
    Hi, I'm new to iPhone dev and need some help with adding subViews. I have a reusable object that I made that is stored in a separate .h .m and xib file. I would like to use this object in my main project's view controller. I have included the header and the assignment of the object generates no errors. I am able to load the object into my main project but can only do things with it inside my viewDidLoad method. I intend to have a few of these objects on my screen and am looking fora solution that is more robust then just hard wiring up multiple copies of the shape object. As soon as I try to access the object outside of the viewDidLoad it produces a variable unknown error - first use in this function. Here is my viewDidLoad method: shapeViewController *shapeView = [[shapeViewController alloc] initWithNibName:@"shapeViewController" bundle:nil]; [self.view addSubview: shapeView.view]; // This is the problem line // This code works changes the display on the shape object [shapeView updateDisplay:@"123456"]; ---- but the same code outside of the viewDidLoad generates the error. So to sum up, everything works except when I try to access the shapeView object in the rest of the methods. Thanks in advance

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  • Null reference exceptions in .net

    - by Carlo
    Hello, we're having this big problem with our application. It's a rather large application with several modules, and thousands and thousands lines of code. A lot of parts of the application are designed to exist only with a reference to another object, for example a Person object can never exists without a House object, so if you at any point in the app say: bool check = App.Person.House == null; check should always be false (by design), so, to keep using that example, while creating modules, testing, debugging, App.Person.House is never null, but once we shipped the application to our client, they started getting a bunch of NullReferenceException with the objects that by design, should never have a null reference. They tell us the bug, we try to reproduce it here, but 90% of the times we can't, because here it works fine. The app is being developed with C# and WPF, and by design, it only runs on Windows XP SP 3, and the .net framework v3.5, so we KNOW the user has the same operative system, service pack, and .net framework version as we do here, but they still get this weird NullReferenceExceptions that we can't reproduce. So, I'm just wondering if anyone has seen this before and how you fixed it, we have the app running here at least 8 hours a day in 5 different computers, and we never see those exceptions, this only happens to the client for some reason. ANY thought, any clue, any solution that could get us closer to fixing this problem will be greatly appreciated. Thanks!

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  • Google Maps in Drupal: reference to gmap object from JavaScript

    - by user280817
    Is there a way to obtain JavaScript references to the Google maps that are embedded into Drupal pages by the GMap module? I want to be able to manipulate the maps in these pages. I want to pan and zoom them. But I cannot find a reference to an embedded map object. I've dissected the relevant JavaScript objects Drupal.gmap and Drupal.settings.gmap with no success--unless I've overlooked something. The Drupal GMap module doesn't seem to explicitly provide references (within its API) to the GMap objects that it embeds into pages. It just generates themed text which is interpolated into the page. The technique of passing the HTML ID of the map container to either the GMap2 object constructor or the similar Drupal.gmap.getMap() function in order to obtain a map reference doesn't appear to work: Both simply return an instance to a new map, one having the same dimensions and basic characteristics of the original map, but apparently sans all of its overlays (which could contain markers). And I have to call setCenter() on it before I can use it, which initializes the structure, so I know it has no overlays.

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  • Strange behavior with complex Q object filter queries in Django

    - by HWM-Rocker
    Hi I am trying to write a tagging system for Django, but today I encountered a strange behavior in filter or the Q object (django.db.models.Q). I wrote a function, that converts a search string into a Q object. The next step would be to filter the TaggedObject with these query. But unfortunately I get a strange behavior. when I search (id=20) = Q: (AND: ('tags__tag__id', 20)) and it returns 2 Taged Objects with the ID 1127 and 132 when I search (id=4) = Q: (AND: ('tags__tag__id', 4)) and it returns also 2 Objects, but this time 1180 and 1127 until here is everything fine, but when i make a little bit more complex query like (id=4) or (id=20) = Q: (OR: ('tags__tag__id', 4), ('tags__tag__id', 20)) then it returns 4(!) Objects 1180, 1127, 1127, 132 But the object with the ID 1127 is returned twice, but thats not the behaviour I want. Do I have to live with it, and uniqify that list or can I do something different. The representation of the Q object looks fine for me. But the worst is now, when I search for (id=20) and (id=4) = Q: (AND: ('tags__tag__id', 20), ('tags__tag__id', 4)) then it returns no object at all. But why? The representation should be ok and the object with the id 1127 is tagged by both. What am I missing? Here are also the relevant parts of the classes, that are involved: class TaggedObject(models.Model): """ class that represent a tagged object """ tags = generic.GenericRelation('ObjectTagBridge', blank=True, null=True) class ObjectTagBridge(models.Model): """ Help to connect a generic object to a Tag. """ # pylint: disable-msg=W0232,R0903 content_type = models.ForeignKey(ContentType) object_id = models.PositiveIntegerField() content_object = generic.GenericForeignKey('content_type', 'object_id') tag = models.ForeignKey('Tag') class Tag(models.Model): ... Thanks for your help

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  • How to make += operator keep the object reference?

    - by orloffm
    Say, I have a class: class M { public int val; And also a + operator inside it: public static M operator +(M a, M b) { M c = new M(); c.val = a.val + b.val; return c; } } And I've got a List of the objects of the class: List<M> ms = new List(); M obj = new M(); obj.val = 5; ms.Add(obj); Some other object: M addie = new M(); addie.val = 3; I can do this: ms[0] += addie; and it surely works as I expect - the value in the list is changed. But if I want to do M fromList = ms[0]; fromList += addie; it doesn't change the value in ms for obvious reasons. But intuitively I expect ms[0] to also change after that. Really, I pick the object from the list and then I increase it's value with some other object. So, since I held a reference to ms[0] in fromList before addition, I want still to hold it in fromList after performing it. Are there any ways to achieve that?

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  • Add webservice reference, the classes in different file

    - by ArunDhaJ
    Hi, When I add webservice as service reference in my .Net project, it creates a service folder within "Service References". All the interfaces and classes are contained within that service folder. I wanted to know how to split the interface's method and classes. Actually I wanted the web service reference to import classes defined in different dll. I wanted to define this way because of my design constraints. I've 3 layered application. Of which third layer is communication layer which holds all web service references. second is business layer and first is presentation layer. If the class declarations are in layer-3 and I'm accessing those classes from presentation layer, it is logically a cross-layer-access-violation. Instead, I wanted a separate project which holds only the class declarations and this would be used in all 3 layers. I didn't faced any problems to achieve this with layer-1 and layer-2. But, I'm not sure how to make communication layer to use this common declaration dll. Your suggestion would help me to design my application better. Thanks in advance Regards ArunDhaJ

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  • SWIG interface to receive an opaque struct reference in Java through function argument

    - by Beeo
    I am trying to use SWIG in order to use the Spotify API (libspotify) for Android: https://developer.spotify.com/technologies/libspotify/ I am having trouble defining the SWIG interface file to be able to successfully call the following native C function: sp_error sp_session_create(const sp_session_config * config, sp_session ** sess); Which in C would be called like this: //config struct defined previously sp_session *sess; sp_session_create(&config, &sess); But in Java I would need to call it like this: //config object defined previously sp_session javaSess = new sp_session(); sp_session_create(config, javaSess); sp_session is an opaque struct and is only defined in libspotify's API.h file as: typedef struct sp_session sp_session; I'm expecting the libspotify library to create it and give me a reference to it. The only thing I need that reference for then is to pass to other functions in the API. I believe the answer lies within the SWIG interface and typemaps, but I have been unsuccessful in trying to apply the examples I found in the documentation: http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_struct_pointer_pointer `http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_using_typemaps_return_arguments Help!

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  • IOS : BAD ACCESS when trying to add a new Entity object

    - by Maverick447
    So i'm using coredata to model my relationships . This is the model in brief Type A can have one or more types of type B Type B has a inverse relationship of being associated with one of type A Type B can have one or more types of type C Type C has a inverse relationship of being associated with one of type B From a UI standpoint , I have a Navigation controller with controllers that successively sets up the first A object (VC-1) , then another viewcontroller (VC-2) creates a B object ( I pass in the A object to this controller) and the B object is added to the A object . Similarly the same thing happens with B and C . The third Viewcontroller (VC3) first creates a C object and assigns it to the passed B Object . Also between these viewcontrollers the managedObjectCOntext is also passed . SO my use case is such that while viewcontroller (VC-3) is the top controller a button action will keep creating multiple objects of type C and add them to the same type B object that was passed . Also as part of this function I save the managedObject context after saving each type C . e.g. code in viewcontroller 3 - (void) SaveNewTypeC { TypeC *newtypeC = (Question*)[NSEntityDescription insertNewObjectForEntityForName:@"TypeC" inManagedObjectContext:managedObjectContext]; [newtypeC setProp1:] ; [newtypeC setProp2:] .. .. **[typeBObject addTypeCInTypeBObject:newtypeC];** [section setTotalCObjectCount:[ NSNumber numberWithInt:typeCIndex++]]; NSError *error = nil; if (![managedObjectContext save:&error]) { // Handle error NSLog(@"Unresolved error %@, %@, %@", error, [error userInfo],[error localizedDescription]); exit(-1); // Fail } [newtypeC release]; } - (IBAction)selectedNewButton:(id)sender { [self SaveNewTypeC]; [self startRepeatingTimer]; } The BAD ACCESS seems to appear when the bold line above executes Relating to some HashValue . Any clues on resolving this would be helpful .

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  • Copy constructor called even when returning by reference?

    - by Johnyy
    Hi, I am testing the return of local objects by reference. My original test went well but something else happens unexpected. #include <iostream> using namespace std; class MyInt { public: MyInt(int i){ value = new int(i); } ~MyInt(){ delete value; } int getValue(){ return *value; } MyInt(const MyInt &b){ cout<<"Copy"<<endl; } private: int* value; }; MyInt& returnref(){ MyInt a(10); cout<<"Returning from returnref()"<<endl; return a; } int main(){ MyInt a = returnref(); cout<<a.getValue()<<endl; return 0; } My console prints "Returning from ..." then "Copy" then a random value. My understanding of pass by reference is that it does not need to make any copy. Why is it not doing what I expected?

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  • detecting object-reference duplication across JavaScript files

    - by AnC
    I have a number of files with contents like this: function hello() { ... element1.text = foo.locale.lorem; element2.text = foo.locale.ipsum; ... elementn.text = foo.locale.whatever; ... } function world() { ... var label = bar.options.baz.blah; var toggle = bar.options.baz.use_toggle; ... } This could be written more efficiently, and also be more readable, by creating a shortcut to the locale object: function hello() { var loc = foo.locale; ... element1.text = loc.lorem; element2.text = loc.ipsum; ... elementn.text = loc.whatever; ... } function world() { var options = bar.options.baz; ... var label = options.blah; var toggle = options.use_toggle; ... } Is there a simple way to detect occurrences of such duplication for any arbitrary object (it's not always as simple as "locale", or foo.something)? Basically, I wanna know where lengthy object references appear two or more times within a function. Thanks!

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  • Reference to the Main Form whilst trying to Serialize objects in C#

    - by Paul Matthews
    I have a button on my main form which calls a method to serialize some objects to disk. I am trying to add these objects to an ArrayList and then serialize them using a BinaryFormatter and a FileStream. public void SerializeGAToDisk(string GenAlgName) { // Let's make a list that includes all the objects we // need to store a GA instance ArrayList GAContents = new ArrayList(); GAContents.Add(GenAlgInstances[GenAlgName]); // Structure and info for a GA GAContents.Add(RunningGAs[GenAlgName]); // There may be several running GA's using (FileStream fStream = new FileStream(GenAlgName + ".ga", FileMode.Create, FileAccess.Write, FileShare.None)) { BinaryFormatter binFormat = new BinaryFormatter(); binFormat.Serialize(fStream, GAContents); } } When running the above code I get the following exception: System.Runtime.Serialization.SerializationException was unhandled Message=Type 'WindowsFormsApplication1.Form1' in Assembly 'GeneticAlgApp, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' is not marked as serializable. So that means that somewhere in the objects I'm trying to save there must be a reference to the main form. The only possible references I can see are 3 delegates which all point to methods in the main form code. Do delegates get serialized as well? I can't seem to apply the [NonSerialized] attribute to them. Is there anything else I might be missing? Even better, is there a quick method to find the reference(s) that are causing the problem?

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  • unexpected behaviour of object stored in web service Session

    - by draconis
    Hi. I'm using Session variables inside a web service to maintain state between successive method calls by an external application called QBWC. I set this up by decorating my web service methods with this attribute: [WebMethod(EnableSession = true)] I'm using the Session variable to store an instance of a custom object called QueueManager. The QueueManager has a property called ChangeQueue which looks like this: [Serializable] public class QueueManager { ... public Queue<QBChange> ChangeQueue { get; set; } ... where QBChange is a custom business object belonging to my web service. Now, every time I get a call to a method in my web service, I use this code to retrieve my QueueManager object and access my queue: QueueManager qm = (QueueManager)Session[ticket]; then I remove an object from the queue, using qm.dequeue() and then I save the modified query manager object (modified because it contains one less object in the queue) back to the Session variable, like so: Session[ticket] = qm; ready for the next web service method call using the same ticket. Now here's the thing: if I comment out this last line //Session[ticket] = qm; , then the web service behaves exactly the same way, reducing the size of the queue between method calls. Now why is that? The web service seems to be updating a class contained in serialized form in a Session variable without being asked to. Why would it do that? When I deserialize my Queuemanager object, does the qm variable hold a reference to the serialized object inside the Session[ticket] variable?? This seems very unlikely.

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  • Web Reference Code generator template.

    - by Bluephlame
    I Have an internal SOAP Web service that is being called from an external REST service in .NET it works fine however I am simply passing through the SOAP objects of the REST Layer but the automatic generation of the WebReference Code in Visual Studio adds the 'field' to the end of every attribute. basically it makes my XML look all nasty. Everything works I just want to clean up my XML. Any ideas how i can change the template for the reference.cs or to make the XML generate nicely from the Web Service Objects. Here is an example of the reference.cs public int HeadLeft { get { return this.headLeftField; } set { this.headLeftField = value; } } /// <remarks/> public int HeadTop { get { return this.headTopField; } set { this.headTopField = value; } } /// <remarks/> public int HeadWidth { get { return this.headWidthField; } set { this.headWidthField = value; } } Here is an examle of the XML <a:headHeightField>208</a:headHeightField> <a:headLeftField>316</a:headLeftField> <a:headTopField>103</a:headTopField> <a:headWidthField>161</a:headWidthField>

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  • Returning a reference from a Class member?

    - by nebukadnezzar
    Hi, I've a class that basically looks like this: class App { public function newTemplate($filename, $vars=array()) { $smarty = new Smarty; $smarty->compile_dir = $this->template_compile_path; if(count($vars) > 0) { foreach($vars as $v_key => $v_name) { $smarty->assign($v_key, $v_name); } } return $smarty; } } However, when I create a Instance of 'App', the reference to $smarty seems broken, as every call to the membermethods don't seem to do anything: $app = new App; $tpl = $app->newTemplate("index.tmpl"); $tpl->assign("foo", "bar"); // {$foo} does not appear with "bar" in the template Now I wonder why? Of course I tried to use references: ... public function &newTemplate() ... ... But that doesn't work. Variable references don't seem to work either: ... $tpl = &$app->newTemplate("index.tmpl"); ... What is causing PHP here not to return a proper reference? Help is very appreciated!

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