Search Results

Search found 25521 results on 1021 pages for 'static objects'.

Page 192/1021 | < Previous Page | 188 189 190 191 192 193 194 195 196 197 198 199  | Next Page >

  • Memory management in Qt?

    - by Martin
    I'm quite new to Qt and am wondering on some basic stuff with memory management and the life of objects. When do I need to delete / destroy my objects? Is any of this handled automatically? In the example below, which of the objects I create do I need to delete? What happens to the instance variable myOtherClass when myClass is destroyed? What happens if I don't delete / destroy my objects at all, will that be a problem to memory? in MyClass.h: class MyClass { public: MyClass(); ~MyClass(); MyOtherClass *myOtherClass; }; in MyClass.cpp: MyClass::MyClass() { myOtherClass = new MyOtherClass(); MyOtherClass myOtherClass2; QString myString = "Hello"; } As you can see this is quite newbie-easy stuff but where can I learn about this in an easy way? Thanks really much

    Read the article

  • Validating disconnected POCOs

    - by jonathanconway
    In my ASP.NET application I have separate projects for the Data, Business and UI layers. My business layer is composed of plain objects with declarative validation, using DataAnnotations. Problem is, when it comes to save them, I'm not sure how to process the validation, since they're not bound directly to any data context, but rather, are mapped to separate data-layer objects. Is there a way to trigger validation on these kinds of objects?

    Read the article

  • Django excluding specific instances from queryset without using field lookup

    - by Agos
    Hi, I sometimes have the need to make sure some instances are excluded from a queryset. This is the way I do it usually: unwanted_instance = Mymodel.objects.get(pk=bad_luck_number) uninteresting_stuff_happens() my_results = MyModel.objects.exclude(id=unwanted_instance.id) or, if I have more of them: my_results = MyModel.objects.exclude(id_in=[uw_in1.id, uw_in2.id, uw_in3.id]) This 'feels' a bit clunky, so I tried if I was lucky: my_ideally_obtained_results = MyModel.objects.exclude(unwanted_instance) Which doesn't work. But I read here on SO that a subquery can be used as parameter for exclude. Am I out of luck? Am I missing some functionality (checked the docs, but didn't find any useful pointer)

    Read the article

  • WPF Listview- What would be the best way to display data from different ObservableCollections based

    - by highone
    I have three ObservableCollections: CharacterCollection, LocationCollection, and ItemCollection. They are all collections of objects; CharacterCollection is a collection of Character Objects. I need to display, in the listview, information from the collection determined by the user clicking on a button. I would prefer to use databinding, but I don't see a clear cut way to do that with multiple collections containing different types of objects. What would be the best way to easily switch between collections?

    Read the article

  • Project change makes qtp to fail

    - by Onnesh
    We are using 2 or more projects in an application to be opened. For e.g. HT1000 & HT1200 will be opened by the application, objects are the same(or common) for both the projects. Code uses the values in excel framework for running the test cases as parent to identify the child objects for e.g. Window("HT1000").Dialog("parts").Click("OK") but when we just change the parent name in excel framework as "HT1200" the objects for HT1200 are not getting accessed. How to resolve this? Is it needed to again add the HT1200 project & objects in the object repo of qtp?

    Read the article

  • Using ret with FASM on Win32

    - by Jon Purdy
    I'm using SDL with FASM, and have code that's minimally like the following: format ELF extrn _SDL_Init extrn _SDL_SetVideoMode extrn _SDL_Quit extrn _exit SDL_INIT_VIDEO equ 0x00000020 section '.text' public _SDL_main _SDL_main: ccall _SDL_Init, SDL_INIT_VIDEO ccall _SDL_SetVideoMode, 640, 480, 32, 0 ccall _SDL_Quit ccall _exit, 0 ; Success, or ret ; failure. With the following quick-and-dirty makefile: SOURCES = main.asm OBJECTS = main.o TARGET = SDLASM.exe FASM = C:\fasm\fasm.exe release : $(OBJECTS) ld $(OBJECTS) -LC:/SDL/lib/ -lSDLmain -lSDL -LC:/MinGW/lib/ -lmingw32 -lcrtdll -o $(TARGET) --subsystem windows cleanrelease : del $(OBJECTS) %.o : %.asm $(FASM) $< $@ Using exit() (or Windows' ExitProcess()) seems to be the only way to get this program to exit cleanly, even though I feel like I should be able to use retn/retf. When I just ret without calling exit(), the application does not terminate and needs to be killed. Could anyone shed some light on this? It only happens when I make the call to SDL_SetVideoMode().

    Read the article

  • C#: Put member variables into a list.

    - by David
    Hi all Assuming I have a method which accepts an IList or similar thing as a parameter: public void JiggleMyList(IList<string> list)... Is there an easy way that I can pass in string members of a list of objects? I mean, if for example, I have a list of Person objects which expose a string property called FullName, is there a quick way to stuff the FullNames of all the Person objects into the method parameter, or do I have to create a new List and iterate through the Person objects: List<string> fullNames = new List<string>; foreach (Person person in people) { fullNames.Add(person.FullName); } JiggleMyList(fullNames); I come across this all the time, and it would be nice if there was a shortcut. Many thanks David

    Read the article

  • Generic Singleton Façade design pattern

    - by Paul
    Hi I try write singleton façade pattern with generics. I have one problem, how can I call method from generic variable. Something like this: T1 t1 = new T1(); //call method from t1 t1.Method(); In method SingletonFasadeMethod I have compile error: Error 1 'T1' does not contain a definition for 'Method' and no extension method 'Method' accepting a first argument of type 'T1' could be found (are you missing a using directive or an assembly reference?) Any advace? Thank, I am beginner in C#. All code is here: namespace GenericSingletonFasade { public interface IMyInterface { string Method(); } internal class ClassA : IMyInterface { public string Method() { return " Calling MethodA "; } } internal class ClassB : IMyInterface { public string Method() { return " Calling MethodB "; } } internal class ClassC : IMyInterface { public string Method() { return "Calling MethodC"; } } internal class ClassD : IMyInterface { public string Method() { return "Calling MethodD"; } } public class SingletonFasade<T1,T2,T3> where T1 : class,new() where T2 : class,new() where T3 : class,new() { private static T1 t1; private static T2 t2; private static T3 t3; private SingletonFasade() { t1 = new T1(); t2 = new T2(); t3 = new T3(); } class SingletonCreator { static SingletonCreator() { } internal static readonly SingletonFasade<T1,T2,T3> uniqueInstace = new SingletonFasade<T1,T2,T3>(); } public static SingletonFasade<T1,T2,T3> UniqueInstace { get { return SingletonCreator.uniqueInstace; } } public string SingletonFasadeMethod() { //Problem is here return t1.Method() + t2.Method() + t3.Method(); } } } I use this for my problem. public class SingletonFasade<T1, T2, T3> where T1 : class, IMyInterface, new() where T2 : class, IMyInterface, new() where T3 : class, IMyInterface, new() {//...} Is any solution without Interfaces ??

    Read the article

  • How do I get a window caption?

    - by P.Brian.Mackey
    I would like to get a Window Caption as given by spy++ (highlighted in red) I have code to do this (or so I thought)...but it seems to work pretty awful....in some cases 1% of the time... public delegate bool EnumDelegate(IntPtr hWnd, int lParam); [DllImport("user32.dll")] [return: MarshalAs(UnmanagedType.Bool)] static extern bool IsWindowVisible(IntPtr hWnd); [DllImport("user32.dll", EntryPoint = "GetWindowText", ExactSpelling = false, CharSet = CharSet.Auto, SetLastError = true)] static extern int GetWindowText(IntPtr hWnd, StringBuilder lpWindowText, int nMaxCount); [DllImport("user32.dll", EntryPoint = "EnumDesktopWindows", ExactSpelling = false, CharSet = CharSet.Auto, SetLastError = true)] static extern bool EnumDesktopWindows(IntPtr hDesktop, EnumDelegate lpEnumCallbackFunction, IntPtr lParam); static List<NativeWindow> collection = new List<NativeWindow>(); public static NativeWindow GetAppNativeMainWindow() { GetNativeWindowHelper.EnumDelegate filter = delegate(IntPtr hWnd, int lParam) { StringBuilder strbTitle = new StringBuilder(255); int nLength = GetNativeWindowHelper.GetWindowText(hWnd, strbTitle, strbTitle.Capacity + 1); string strTitle = strbTitle.ToString(); if (!string.IsNullOrEmpty(strTitle)) { if (strTitle.ToLower().StartsWith("window title | my application")) { NativeWindow window = new NativeWindow(); window.AssignHandle(hWnd); collection.Add(window); return false;//stop enumerating } } return true;//continue enumerating }; GetNativeWindowHelper.EnumDesktopWindows(IntPtr.Zero, filter, IntPtr.Zero); if (collection.Count != 1) { //log error ReleaseWindow(); return null; } else return collection[0]; } public static void ReleaseWindow() { foreach (var item in collection) { item.ReleaseHandle(); } }

    Read the article

  • Thread safe lazy contruction of a singleton in C++

    - by pauldoo
    Is there a way to implement a singleton object in C++ that is: Lazily constructed in a thread safe manner (two threads might simultaneously be the first user of the singleton - it should still only be constructed once). Doesn't rely on static variables being constructed beforehand (so the singleton object is itself safe to use during the construction of static variables). (I don't know my C++ well enough, but is it the case that integral and constant static variables are initialized before any code is executed (ie, even before static constructors are executed - their values may already be "initialized" in the program image)? If so - perhaps this can be exploited to implement a singleton mutex - which can in turn be used to guard the creation of the real singleton..) Excellent, it seems that I have a couple of good answers now (shame I can't mark 2 or 3 as being the answer). There appears to be two broad solutions: Use static initialisation (as opposed to dynamic initialisation) of a POD static varible, and implementing my own mutex with that using the builtin atomic instructions. This was the type of solution I was hinting at in my question, and I believe I knew already. Use some other library function like pthread_once or boost::call_once. These I certainly didn't know about - and am very grateful for the answers posted.

    Read the article

  • PHP anonymous functions scope question

    - by Dan
    Hi, I'm trying to sort an array of objects by a common property, however I cannot get my $property parameter to register in the inner function (I can use it in the outer one OK). The way I read the documentation, it sounded like the parameter would be available, have I misunderstood something? Here is what I have: public static function sortObjectsByProperty($objects, $property) { function compare_object($a, $b) { $a = $a->$property; $b = $b->$property; if ($a->$property == $b->$property) { return 0; } return ($a->$property > $b->$property) ? +1 : -1; } usort($objects, 'compare_object'); return $objects; } Any advice appreciated. Thanks.

    Read the article

  • Avoiding null point exception in el in JSF

    - by Buddhika Ariyaratne
    I am developing a JSF application with JPA(EclipseLink 2.0) and Primefaces. I want to know is there any way to avoid null point exception when el calls a property of a null object. I have described the situation. I have Bill class. There may be no or more BillItem objects with a Bill objects. Each BillItem object have Objects like Make, Country, Manufacturer, etc objects. I am displaying several properties of a bill within a single JSF file like this. "#{billControlled.bill.billItem.modal.name}" But if a bill is not selected, or when there are no bill items for a selected bill, the properties accessing in the el are null. I can avoid this by creating new objects for every bill, for example, new make for a new bill item, etc or by creating new properties in the controller itself for all the properties. But that is a very long way and feel like rudimentory. Is there any good practice to avoid this null point exception in el in JSF?

    Read the article

  • SQL Alchemy MVC and cross controller joins

    - by Khorkrak
    When using SQL Alchemy for abstracting your data access layer and using controllers as the way to access objects from that abstraction layer, how should joins be handled? So for example, say you have an Orders controller class that manages Order objects such that it provides getOrder, saveOrder, etc methods and likewise a similar controller for User objects. First of all do you even need these controllers? Should you instead just treat SQL Alchemy as "the" thing for handling data access. Why bother with object oriented controller stuff there when you instead have a clean declarative way to obtain and persist objects without having to write SQL directly either. Well one reason could be that perhaps you may want to replace SQL Alchemy with direct SQL or Storm or whatever else. So having controller classes there to act as an intermediate layer helps limit what would need to change then. Anyway - back to the main question - so assuming you have these two controllers, now lets say you want the list of orders for a certain set of users meeting some criteria. How do you go about doing this? Generally you don't want the controllers crossing domains - the Orders controllers knows only about Orders and the User controller just about Users - they don't mess with each other. You also don't want to go fetch all the Users that match and then feed a big list of user ids to the Orders controller to go find the matching Orders. What's needed is a join. Here's where I'm stuck - that seems to mean either the controllers must cross domains or perhaps they should be done away with altogether and you simply do the join via SQL Alchemy directly and get the resulting User and / or Order objects as needed. Thoughts?

    Read the article

  • using the ASP.NET Caching API via method annotations in C#

    - by craigmoliver
    In C#, is it possible to decorate a method with an annotation to populate the cache object with the return value of the method? Currently I'm using the following class to cache data objects: public class SiteCache { // 7 days + 6 hours (offset to avoid repeats peak time) private const int KeepForHours = 174; public static void Set(string cacheKey, Object o) { if (o != null) HttpContext.Current.Cache.Insert(cacheKey, o, null, DateTime.Now.AddHours(KeepForHours), TimeSpan.Zero); } public static object Get(string cacheKey) { return HttpContext.Current.Cache[cacheKey]; } public static void Clear(string sKey) { HttpContext.Current.Cache.Remove(sKey); } public static void Clear() { foreach (DictionaryEntry item in HttpContext.Current.Cache) { Clear(item.Key.ToString()); } } } In methods I want to cache I do this: [DataObjectMethod(DataObjectMethodType.Select)] public static SiteSettingsInfo SiteSettings_SelectOne_Name(string Name) { var ck = string.Format("SiteSettings_SelectOne_Name-Name_{0}-", Name.ToLower()); var dt = (DataTable)SiteCache.Get(ck); if (dt == null) { dt = new DataTable(); dt.Load(ModelProvider.SiteSettings_SelectOne_Name(Name)); SiteCache.Set(ck, dt); } var info = new SiteSettingsInfo(); foreach (DataRowView dr in dt.DefaultView) info = SiteSettingsInfo_Load(dr); return info; } Is it possible to separate those concerns like so: (notice the new annotation) [CacheReturnValue] [DataObjectMethod(DataObjectMethodType.Select)] public static SiteSettingsInfo SiteSettings_SelectOne_Name(string Name) { var dt = new DataTable(); dt.Load(ModelProvider.SiteSettings_SelectOne_Name(Name)); var info = new SiteSettingsInfo(); foreach (DataRowView dr in dt.DefaultView) info = SiteSettingsInfo_Load(dr); return info; }

    Read the article

  • Do you know of a free .Net component for visual flow model graph design and editing?

    - by Ivan
    An app (C#4, WinForms, Entity Framework, SQL Server 2008) of mine maintains a graph of interconnected objects, each having some simple member fields and a set of many directed (in and out) one-to-one links to other objects. I'd like to offer a user an ability to view and edit this graph visually some way, creating and removing connections, modifying objects attributes values and introducing/dropping objects. I suppose there has to be a framework (at list a primitive kind of) for this as visual model design tools are pretty common to meet. Do you know one?

    Read the article

  • DeSerialization doesn't work though i Implement GetObjectData method and Constructor

    - by Punit Singhi
    Hi, I have a static generic dictionary in a class. As static memeber cannot serialized so i have implented ISerializable interface and method GetObjectData to serialize. I have a constructor which will also accept SerializationInfo and StreamingContext to deserliaze the dictionay. Now when i try to serialize and deserialize , it always return 1(thoug i added 2 entries). please find the pseduo code- [Serializable] public class MyClass : ISerializable { internal static Dictionary<long, string> dict = new Dictionary<long,string>(); public void GetObjectData(SerializationInfo info, StreamingContext context) { info.AddValue("static.dic", MyClass1.dict, typeof(Dictionary<long, string>)); } public MyClass(SerializationInfo info, StreamingContext context) { MyClass.dict= (Dictionary<long, string>)info.GetValue("static.dic", typeof(Dictionary<long, string>)); } public void Add() { dict.Add(21, "11"); } public MyClass() { dict.Add(21, "11"); } } public class MyClass { MyClass myClass = new MyClass(); public static void Main() { myClass.Add(); FileStream fileStream = new FileStream("test.binary", FileMode.Create); IFormatter bf = new BinaryFormatter(); bf.Serialize(fileStream, myClass); fileStream.Dispose(); fileStream.Close(); fileStream = new FileStream("test.binary", FileMode.Open); bf = new BinaryFormatter(); myClass = (MyClass1)bf.Deserialize(fileStream); } }

    Read the article

  • Ret Failure with SDL using FASM on Win32

    - by Jon Purdy
    I'm using SDL with FASM, and have code that's minimally like the following: format ELF extrn _SDL_Init extrn _SDL_SetVideoMode extrn _SDL_Quit extrn _exit SDL_INIT_VIDEO equ 0x00000020 section '.text' public _SDL_main _SDL_main: ccall _SDL_Init, SDL_INIT_VIDEO ccall _SDL_SetVideoMode, 640, 480, 32, 0 ccall _SDL_Quit ccall _exit, 0 ; Success, or ret ; failure. With the following quick-and-dirty makefile: SOURCES = main.asm OBJECTS = main.o TARGET = SDLASM.exe FASM = C:\fasm\fasm.exe release : $(OBJECTS) ld $(OBJECTS) -LC:/SDL/lib/ -lSDLmain -lSDL -LC:/MinGW/lib/ -lmingw32 -lcrtdll -o $(TARGET) --subsystem windows cleanrelease : del $(OBJECTS) %.o : %.asm $(FASM) $< $@ Using exit() (or Windows' ExitProcess()) seems to be the only way to get this program to exit cleanly, even though I feel like I should be able to use retn/retf. When I just ret without calling exit(), the application does not terminate and needs to be killed. Could anyone shed some light on this? It only happens when I make the call to SDL_SetVideoMode().

    Read the article

  • Inference engine to calculate matching set according to internal rules

    - by Zecrates
    I have a set of objects with attributes and a bunch of rules that, when applied to the set of objects, provides a subset of those objects. To make this easier to understand I'll provide a concrete example. My objects are persons and each has three attributes: country of origin, gender and age group (all attributes are discrete). I have a bunch of rules, like "all males from the US", which correspond with subsets of this larger set of objects. I'm looking for either an existing Java "inference engine" or something similar, which will be able to map from the rules to a subset of persons, or advice on how to go about creating my own. I have read up on rule engines, but that term seems to be exclusively used for expert systems that externalize the business rules, and usually doesn't include any advanced form of inferencing. Here are some examples of the more complex scenarios I have to deal with: I need the conjunction of rules. So when presented with both "include all males" and "exclude all US persons in the 10 - 20 age group," I'm only interested in the males outside of the US, and the males within the US that are outside the 10 - 20 age group. Rules may have different priorities (explicitly defined). So a rule saying "exclude all males" will override a rule saying "include all US males." Rules may be conflicting. So I could have both an "include all males" and an "exclude all males" in which case the priorities will have to settle the issue. Rules are symmetric. So "include all males" is equivalent to "exclude all females." Rules (or rather subsets) may have meta rules (explicitly defined) associated with them. These meta rules will have to be applied in any case that the original rule is applied, or if the subset is reached via inferencing. So if a meta rule of "exclude the US" is attached to the rule "include all males", and I provide the engine with the rule "exclude all females," it should be able to inference that the "exclude all females" subset is equivalent to the "include all males" subset and as such apply the "exclude the US" rule additionally. I can in all likelihood live without item 5, but I do need all the other properties mentioned. Both my rules and objects are stored in a database and may be updated at any stage, so I'd need to instantiate the 'inference engine' when needed and destroy it afterward.

    Read the article

  • Deleting entity with child relationships using .Net Entity Framework problem

    - by Am
    My God, EF is so frustrating. I can't seem to be able to get my head around what I need to do so I can delete an object. I seem to be able to remove the object but not the related child objects. Can anyone tell me what is the rule of thumb when you want to delete all related child objects of a given object? I've tried loading all related objects like this: if (!object.childobjects.IsLoaded) object.childobjects.Load(); but once I do the following I get errors related to the relationships: modelcontext.DeleteObject(object); modelcontext.SaveChanges(); Why can't I just load the object using modelcontext.GetObjectByKey and remove it along with its child objects? My other question is can I delete an object using Entity command like so? DELETE e from objectset as e where e.id = 12 I've tried few variations and all of them throw exceptions.

    Read the article

  • How to write async background workers that work on WPF flowdocument

    - by iBe
    I'm trying to write a background worker that processes a flowdocument. I can't access the properties of flowdocument objects because of the thread verification. I tried to serialize the document and loaded it on the worker thread which actually solved the thread verfication issue. However, once the processing is complete I also need to use things like TextPointer objects. Those objects now point to a objects in the copy not the original. Can anyone suggest the best way to approach such background processing in WPF?

    Read the article

  • Ajax data two-way data binding strategies?

    - by morgancodes
    I'd like to 1) Draw create form fields and populate them with data from javascript objects 2) Update those backing objects whenever the value of the form field changes Number 1 is easy. I have a few js template systems I've been using that work quite nicely. Number 2 may require a bit of thought. A quick google search on "ajax data binding" turned up a few systems which seem basically one-way. They're designed to update a UI based on backing js objects, but don't seem to address the question of how to update those backing objects when changes are made to the UI. Can anyone recommend any libraries which will do this for me? It's something I can write myself without too much trouble, but if this question has already been thought through, I'd rather not duplicate the work.

    Read the article

  • NSUndoManager, Core Data and selective undo/redo

    - by Combat
    I'm working on a core data application that has a rather large hierarchy of managed objects similar to a tree. When a base object is created, it creates a few child objects which in turn create their own child objects and so on. Each of these child objects may gather information using NSURLConnections. Now, I'd like to support undo/redo with the undoManager in the managedObjectContext. The problem is, if a user creates a base object, then tries to undo that action, the base object is not removed. Instead, one or more of the child objects may be removed. Obviously this type of action is unpredictable and unwanted. So I tried disabling undo registration by default. I did this by calling disableUndoRegistration: before anything is modified in the managedObjectContext. Then, enabling undo registration before base operations such as creating a base object the again re-disabling registrations afterwords. Now when i try to undo, I get this error: undo: NSUndoManager 0x1026428b0 is in invalid state, undo was called with too many nested undo groups Thoughts?

    Read the article

  • Hierarchy / Flyweight / Instancing Problem in Python

    - by Dan
    Here is the problem I am trying to solve, (I have simplified the actual problem, but this should give you all the relevant information). I have a hierarchy like so: 1.A 1.B 1.C 2.A 3.D 4.B 5.F (This is hard to illustrate - each number is the parent, each letter is the child). Creating an instance of the 'letter' objects is expensive (IO, database costs, etc), so should only be done once. The hierarchy needs to be easy to navigate. Children in the hierarchy need to have just one parent. Modifying the contents of the letter objects should be possible directly from the objects in the hierarchy. There needs to be a central store containing all of the 'letter' objects (and only those in the hierarchy). 'letter' and 'number' objects need to be possible to create from a constructor (such as Letter(**kwargs) ). It is perfectably acceptable to expect that when a letter changes from the hierarchy, all other letters will respect the same change. Hope this isn't too abstract to illustrate the problem. What would be the best way of solving this? (Then I'll post my solution) Here's an example script: one = Number('one') a = Letter('a') one.addChild(a) two = Number('two') a = Letter('a') two.addChild(a) for child in one: child.method1() for child in two: print '%s' % child.method2()

    Read the article

  • Looking for an elegant way to store one-to-many relationship in coredata when order is important

    - by Eric Schweichler
    I've been trying to come up with a way to solve my problem, but every solution I can think of is messy and makes me want to retch. I have a one-to-many relationship, consisting of a Team object that can have many Member objects. When I built my data model using Xcode, I was given the default NSSet in which to store the member objects, Unfortunately Sets are not ordered and I need to preserve the order of the Member objects and I need to know if there are empty spaces between Members. I thought of Using an NSArray in place of the NSSet and creating a dummy Member object in my data store that I could use to mark vacant a spot between to Member objects, but that solution really feels like too much of a hack to me. Since I'll always have to filter out this dummy Member from any queries. An NSDictionary would be perfect as I could store the Member object references and their positions as Object-Key pairs, (taking care of both order and vacancies) but apparently CoreData does not support NSDictionary. Has anyone had a similar need, and devised a simple solution?

    Read the article

< Previous Page | 188 189 190 191 192 193 194 195 196 197 198 199  | Next Page >