Search Results

Search found 12001 results on 481 pages for 'naked objects'.

Page 352/481 | < Previous Page | 348 349 350 351 352 353 354 355 356 357 358 359  | Next Page >

• C++ Multithreaded server help

  - by kisplit

  Hello all, I'm working on a multithreaded server in c++ using boost-asio. Currently a design problem I'm running into deals with erasing a connection. I have a single server instance which holds a vector of connection objects. These connections receive commands which I parse. One command in particular deals with sending data to ALL connections in my vector. Now when a connection disconnects I'm currently erasing this connection from the vector and calling the destructor. It seems like I'm going to run into problems when someone 'SendAll' at the same time someone 'Disconnect'. Could anyone recommend a better design or just point me in the right direction? Any help greatly appreciated. Thanks

  Read the article

• How do I change the background image of my iPhone app?

  - by alJaree

  Hello I have looked around and found some code which so called chooses an image from an array of image objects, but cant find an explanation. I would like to make my app have a background image and the user can select next and previous buttons to scroll through some full screen images, setting them as the background image as they scroll. I know how to do this in java, but cant seem to do it for this app. How or what code is linked to a next button to grab the next image in the array and reverse for the back button? Then that needs to be displayed obviously. I have used a layered architecture with a MVC style approach but cant seem to put it together with Objective-C. Would the buttons call the appropriate methods of the so called delegates, which the delegates handle fetching and returning the Images? Would the buttons use the returned images and actually handle the redrawing? I would really appreciate the help. Regards Jarryd

  Read the article

• Restricting deletion with NHibernate

  - by FrontSvin

  I'm using NHibernate (fluent) to access an old third-party database with a bunch of tables, that are not related in any explicit way. That is a child tables does have parentID columns which contains the primary key of the parent table, but there are no foreign key relations ensuring these relations. Ideally I would like to add some foreign keys, but cannot touch the database schema. My application works fine, but I would really like impose a referential integrity rule that would prohibit deletion of parent objects if they have children, e.i. something similar 'ON DELETE RESTRICT' but maintained by NHibernate. Any ideas on how to approach this would be appreciated. Should I look into the OnDelete() method on the IInterceptor interface, or are there other ways to solve this? Of course any solution will come with a performance penalty, but I can live with that.

  Read the article

• Design pattern for data entry forms with LINQ2SQL

  - by petebob796

  I am about to start a new winforms data entry application, it already has the database designed which I am comfortable with. I was going to use LINQ2SQL to access the tables to keep things type safe but am now wondering about design patterns, something I am just getting into. Since LINQ is giving me objects to use should I still create classes in between to hold the validation code and helper methods or should these just go in with the UI? It just seems I will end up with classes sat in between with little code which will cause the UI classes to have code just getting and setting values in the intermediate class and returning from validation to flag errors... Any good reading on this? Should I consider the entity framework (or similar) instead?

  Read the article

• Is there a difference between `==` and `is` in python?

  - by Bernard

  My Google-fu has failed me. In Python, are these: n = 5 # Test one. if n == 5: print 'Yay!' # Test two. if n is 5: print 'Yay!' two tests for equality equivalent (ha!)? Does this hold true for objects where you would be comparing instances (a list say)? Okay, so this kind of answers my question: l = list() l.append(1) if l == [1]: print 'Yay!' # Holds true, but... if l is [1]: print 'Yay!' # Doesn't. So == tests value where is tests to see if they are the same object?

  Read the article

• Accessing HttpApplication.Application variables from a class

  - by Young Ninja

  I set up various global parameters in Global.asax, as such: Application["PagePolicies"] = "~/Lab/Policies.aspx"; Application["PageShare"] = "/Share.aspx"; Application["FileSearchQueries"] = Server.MapPath("~/Resources/SearchQueries.xml"); ... I have no problem accessing these variables form .ascx.cs or .aspx.cs file -- ie. files that are part of the Web content. However, I can't seem to access 'Application' from basic class objects (ie. standalone .cs files). I read somewhere to use a slight variations in .cs files, as follows, but it always comes throws an exception when in use: String file = (String)System.Web.HttpContext.Current.Application["FileSearchQueries"];

  Read the article

• How do you reference another element in a xaml list

  - by Ball

  I'm using xaml as a datastore because It's quick and we haven't yet defined a file format. But I can only seem to create xaml that is a pure tree, even if it is acyclic. I know how to create a list of items in xaml, but How do I share objects in two lists? Below is an example of what I'm trying to say. <CreaturFile> <CreatureFile.Monsters> <Monster Name="Kobold" x:Name="Mepo"/> <Monster Name="Goblin"/> </CreatureFile.Monsters> <CreatureFile.Encounters> <Encounter> <Reference ElementName="Mepo"/> </Encounter> </CreatureFile.Encounters> </CreatureFile>

  Read the article

• Subsonic foreign key returning collection?

  - by Shaul

  I'm just writing my first "Hello World" program using Subsonic, for which I've thrown together a simple little Customer/Invoice/InvoiceItem/Product database. The connection was successfully made to the DB, and it generated all the right ActiveRecord classes. But for some reason, the Invoice class has a property called Customers, which returns a collection of Customer objects, even though the Invoice table has a CustomerID field which has a foreign key to the Customer table. I would have expected a Customer property returning a single Customer object. I must be doing something wrong - but what?

  Read the article

• getElementsByTagName() equivalent for textNodes

  - by levik

  Is there any way to get the collection of all textNode objects within a document? getElementsByTagName() works great for Elements, but textNodes are not Elements. Update: I realize this can be accomplished by walking the DOM - as many below suggest. I know how to write a DOM-walker function that looks at every node in the document. I was hoping there was some browser-native way to do it. After all it's a little strange that I can get all the <input>s with a single built-in call, but not all textNodes.

  Read the article

• Creating seed model from data already in DB

  - by Nick Brown

  Is there a way to convert data in an existing database into objects that can easily be put into a seed method? Essentially I'd like to let some people add lines to my DB via a form and then convert that into an object that I can re-seed the DB anytime I need to make changes. The database itself is created via code-first using the following model: public class Combo { public int Id { get; set; } public string MainPrefix { get; set; } public string MainDescriptor { get; set; } public string MainDish { get; set; } public string Connector { get; set; } public string SecondaryDescriptor { get; set; } public string SecondaryDish { get; set; } }

  Read the article

• iPhone - Create not persistant entities in core data

  - by ncohen

  Hi everyone, I would like to use entity objects but not store them... I read that I could create them like this: myElement = (Element *)[NSEntityDescription insertNewObjectForEntityForName:@"Element" inManagedObjectContext:managedObjectContext]; And right after that remove them: [managedObjectContext deleteObject:myElement]; then I can use my elements: myElement.property1 = @"Hello"; This works pretty well even though I think this is probably not the most optimal way to do it... Then I try to use it in my UITableView... the problem is that the object get released after the initialization. My table becomes empty when I move it! Thanks

  Read the article

• Looking at the C++ new[] cookie. How portable is this code?

  - by carleeto

  I came up with this as a quick solution to a debugging problem - I have the pointer variable and its type, I know it points to an array of objects allocated on the heap, but I don't know how many. So I wrote this function to look at the cookie that stores the number of bytes when memory is allocated on the heap. template< typename T > int num_allocated_items( T *p ) { return *((int*)p-4)/sizeof(T); } //test #include <iostream> int main( int argc, char *argv[] ) { using std::cout; using std::endl; typedef long double testtype; testtype *p = new testtype[ 45 ]; //prints 45 std::cout<<"num allocated = "<<num_allocated_items<testtype>(p)<<std::endl; delete[] p; return 0; } I'd like to know just how portable this code is.

  Read the article

• How do I convert a Python list of lists of lists into a C array by using ctypes?

  - by pc05

  As seen here How do I convert a Python list into a C array by using ctypes? this code will take a python array and transform it to a C array. import ctypes arr = (ctypes.c_int * len(pyarr))(*pyarr) Which would the way of doing the same with a list of lists or a lists of lists of lists? For example, for the following variable list3d = [[[40.0, 1.2, 6.0, 0.3], [50.0, 4.2, 0, 0]], [[40.0, 1.2, 6.0, 0.3], [50.0, 4.2, 0, 0]], [[40.0, 1.2, 6.0, 0.3], [50.0, 4.2, 0, 0]]] I have tried the following with no luck: ([[ctypes.c_double * 4] *2]*3)(*list3d) # *** TypeError: 'list' object is not callable (ctypes.c_double * 4 *2 *3)(*list3d) # *** TypeError: expected c_double_Array_4_Array_2 instance, got list Thank you! EDIT: Just to clarify, I am trying to get one object that contains the whole multidimensional array, not a list of objects. This object's reference will be an input to a C DLL that expects a 3D array.

  Read the article

• Proper usage of Java Weak Reference in case of nested collections

  - by Tong Wang

  I need to define a weak reference Map, whose value is a Set. I use Google collections' MapMaker, like this: Map<Class<? extends Object>, Set<Foo>> map = new MapMaker().weakKeys().weakValues().makeMap(); So, for Set<Foo>, can I use a normal HashSet? Or, do I have to create a weak HashSet, like this: Collections.newSetFromMap(new WeakHashMap<Foo, Boolean>()); And why? Another question, the key of my map is Class objects, when will a Class object become weakly reachable? In other words, what is the lifetime of a Class object? Thanks.

  Read the article

• How can I make a read-only ObservableCollection property?

  - by thrag

  I'd like to expose a property on a view model that contains a list of objects (from database). I need this collection to be read-only. That is, I want to prevent Add/Remove, etc. But allow the foreach and indexers to work. My intent is to declare a private field holding the editable collection and reference it with a read-only Public Property. As follows public ObservableCollection<foo> CollectionOfFoo { get { return _CollectionOfFoo; } } However, that syntax just prevents changing the reference to the collection. It doesn't prevent add/remove, etc. What is the right way to accomplish this?

  Read the article

• Deserializing only select properties of an Entity using JDOQL query string?

  - by user246114

  Hi, I have a rather large class stored in the datastore, for example a User class with lots of fields (I'm using java, omitting all decorations below example for clarity): @PersistenceCapable class User { private String username; private String city; private String state; private String country; private String favColor; } For some user queries, I only need the favColor property, but right now I'm doing this: SELECT FROM " + User.class.getName() + " WHERE username == 'bob' which should deserialize all of the entity properties. Is it possible to do something instead like: SELECT username, favColor FROM " + User.class.getName() + " WHERE username == 'bob' and then in this case, all of the returned User instances will only spend time deserializing the username and favColor properties, and not the city/state/country properties? If so, then I suppose all the other properties will be null (in the case of objects) or 0 for int/long/float? Thank you

  Read the article

• Accessing items from a dictionary using pickle efficiently in Python

  - by user248237

  I have a large dictionary mapping keys (which are strings) to objects. I pickled this large dictionary and at certain times I want to pull out only a handful of entries from it. The dictionary has usually thousands of entries total. When I load the dictionary using pickle, as follows: from cPickle import * # my dictionary from pickle, containing thousands of entries mydict = open(load('mypickle.pickle')) # accessing only handful of entries here for entry in relevant_entries: # find relevant entry value = mydict[entry] I notice that it can take up to 3-4 seconds to load the entire pickle, which I don't need, since I access only a tiny subset of the dictionary entries later on (shown above.) How can I make it so pickle only loads those entries that I have from the dictionary, to make this faster? Thanks.

  Read the article

• how to access jquery internal data?

  - by Unknown

  As you may or may not be aware as of jQuery 1.7 the whole event system was rewritten from the ground up. The codebase is much faster and with the new .on() method there is a lot of uniformity to wiring up event handlers. One used to be able to access the internal events data and investiate what events are registered on any given element, but recently this internal information has been hidden based on the following scenario... It seems that the "private" data is ALWAYS stored on the .data(jQuery.expando) - For "objects" where the deletion of the object should also delete its caches this makes some sense. In the realm of nodes however, I think we should store these "private" members in a separate (private) cache so that they don't pollute the object returned by $.fn.data()" Although I agree with the above change to hide the internal data, I have found having access to this information can be helpful for debugging and unit testing. What was the new way of getting the internal jquery event object in jQuery 1.7?

  Read the article

• Combining XmlSerializer and XmlWriter?

  - by num3ric

  In addition to a list of objects I am serializing to an xml file using C#'s XmlSerializer, I would like to store a few more independent elements (mainly strings from textboxes) in the same xml. public static void SaveBehaviors(ObservableCollection<Param> listParams) { XmlSerializer _paramsSerializer = new XmlSerializer(listParams.GetType()); string path = Environment.GetFolderPath(Environment.SpecialFolder.Desktop); path += "\\test.xml"; using (TextWriter writeFileStream = new StreamWriter(path)) { _paramsSerializer.Serialize(writeFileStream, listParams); using (XmlWriter writer = XmlWriter.Create(writeFileStream)) { writer.WriteStartElement("Foo"); //test entry... writer.WriteAttributeString("Bar", "Some & value"); writer.WriteElementString("Nested", "data"); writer.WriteEndElement(); } } } However, deserializing "test.xml" results in an error because of the added element. I suppose writing in the serialized xml file is prohibited and should be avoided?

  Read the article

• How do I perform a dynamic select in Linq?

  - by Matt Mangold

  I am trying to figure out how to dynamically specify the properties for my select clause in a linq query. Lets say I have a collection of employee objects. At run time, the end user will be specifying which properties they would like to see for those employees, so I need to be able to dynamically construct my Linq select clause. I have used the dynamic Linq library, but I prefer not to use that, because it requires me to build a string to pass to the select method. I'd like to understand how to do this via Expressions.

  Read the article

• Question about memory usage

  - by sudo rm -rf

  Hi there. I have the following method: +(NSMutableDictionary *)getTime:(float)lat :(float)lon { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; NSMutableDictionary *dictionary = [[NSMutableDictionary alloc] init]; [dictionary setObject:hour forKey:@"hour"]; [dictionary setObject:minute forKey:@"minute"]; [dictionary setObject:ampm forKey:@"ampm"]; return dictionary; } A lot of the method is chopped off, so I think I need the pool for some other stuff in the method. Here's my question. I know that I need to release the following objects: [dictionary release]; [pool release]; However, I can't release the dictionary before I return it, but as soon as I return it the rest of the method isn't performed. What should I do?

  Read the article

• Improve SQL strategy - denormalize in object-children-images case

  - by fesja

  Hi, I have a Tour object which has many Place objects. For the list of tours, I want to show some info of the tour, the number of places of the tour, and three Place's images. Right one my SQL queries are (i'm using Doctrine with Symfony on MySQL) get Tour get Tour 1 places get Tour 2 places get Tour 3 places ... get Tour n places If I have a three Tour list, it's not so bad; but I'm sure it can get bad if I do a 10-20 tour-list. So, thinking on how to improve the queries I've thought of several measures: Having a place count cache Storing the urls of three images on a new tour field. The problem with 2. is that if I change the image, I have to check all the tours to update that image for another one. What solution do you think is best to scale the system in a near future? Any other suggestion. thanks!

  Read the article

• Substituting variables in a loop?

  - by jksl

  I am trying to write a loop in R but I think the nomenclature is not correct as it does not create the new objects, here is a simplified example of what I am trying to do: for i in (1:8) { List_i <-List colsToGrab_i <-grep(predefinedRegex_i, colnames(List_i$table)) List_i$table <- List_i$table[,predefinedRegex_i] } I have created 'predefinedRegex'es 1:8 which the grep should use to search The loop creates an object called "List_i" and then fails to find "predefinedRegex_i". I have tried putting quotes around the "i" and $ in front of the i but these do not work. Any help much appreciated. Thank you.

  Read the article

• Why are there two implementations of std::sort (with and without a comparator) rather than one implementation with a default template parameter?

  - by PolyVox

  In my code I'm adopting a design strategy which is similar to some standard library algorithms in that the exact behavior can be customized by a function object. The simplest example is std::sort, where a function object can control how the comparison is made between objects. I notice that the Visual C++ provides two implementations of std::sort, which naturally involves code duplication. I would have imagined that it was instead possible to have only one implementation, and provide a default comparator (using operator< ) as a default template parameter. What is the rational behind two separate versions? Would my suggestion make the interface more complex in some way? Or result in confusing error messages when the object does not provide operator Thanks, David

  Read the article

• Does C++ require a destructor call for each placement new?

  - by Josh Haberman

  I understand that placement new calls are usually matched with explicit calls to the destructor. My question is: if I have no need for a destructor (no code to put there, and no member variables that have destructors) can I safely skip the explicit destructor call? Here is my use case: I want to write C++ bindings for a C API. In the C API many objects are accessible only by pointer. Instead of creating a wrapper object that contains a single pointer (which is wasteful and semantically confusing). I want to use placement new to construct an object at the address of the C object. The C++ object will do nothing in its constructor or destructor, and its methods will do nothing but delegate to the C methods. The C++ object will contain no virtual methods. I have two parts to this question. Is there any reason why this idea will not work in practice on any production compiler? Does this technically violate the C++ language spec?

  Read the article

< Previous Page | 348 349 350 351 352 353 354 355 356 357 358 359  | Next Page >