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• Is it possible to store controls(Panel) as object, serialize it and store it as a file?

  - by ikky

  The topic says it all. Using Compact Framework C# I'm tiling (order/sequence is important) some images that i download from an url, into a Panel(each image is a PictureBox). This can be a huge process, and may take some time. Therefor i only want the user to download the images and tile them once. So the next time the user uses the Tile Application, the Panel that was created the first time is already stored in a file and is loaded from that file. So what i want is a method to store a Panel as a file. Is this possible, or do you think i should do it another way? I've tried something like this: BinaryWriter panelStorage = new BinaryWriter(new FileStream("imagePanel.panel", FileMode.OpenOrCreate, FileAccess.Write, FileShare.None)); Byte[] bImageObject = new Byte[20000]; bImageObject = (byte[])(object)this.imagePanel; panelStorage .Write(bMapObject); panelStorage .Close(); But the casting was not very legal :P "InvalidCastException" Can anyone help me with this problem? Thank you in advance!

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• What is the equivalent of .NET events in Ruby?

  - by Gishu

  The problem is very simple. An object needs to notify some events that might be of interest to observers. When I sat to validate a design that I cooked up now in Ruby just to validate it.. I find myself stumped as to how to implement the object events. In .Net this would be a one-liner.. .Net also does handler method signature verification,etc. e.g. // Object with events public delegate void HandlerSignature(int a); public event HandlerSignature MyEvent; public event HandlerSignature AnotherCriticalEvent; // Client MyObject.MyEvent += new HandlerSignature(MyHandlerMethod); // MyHandlerMethod has same signature as delegate Is there an EventDispatcher module or something that I am missing that I can strap on to a Ruby class ? Hoping for an answer that plays along with Ruby's principle of least surprise. An event would be the name of the event plus a queue of [observer, methodName] objects that need to be invoked when the event takes place.

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• Can the Diamond Problem be really solved?

  - by Mecki

  A typical problem in OO programming is the diamond problem. I have parent class A with two sub-classes B and C. A has an abstract method, B and C implement it. Now I have a sub-class D, that inherits of B and C. The diamond problem is now, what implementation shall D use, the one of B or the one of C? People claim Java knows no diamond problem. I can only have multiple inheritance with interfaces and since they have no implementation, I have no diamond problem. Is this really true? I don't think so. See below: [removed vehicle example] Is a diamond problem always the cause of bad class design and something neither programmer nor compiler needs to solve, because it shouldn't exist in the first place? Update: Maybe my example was poorly chosen. See this image Of course you can make Person virtual in C++ and thus you will only have one instance of person in memory, but the real problem persists IMHO. How would you implement getDepartment() for GradTeachingFellow? Consider, he might be student in one department and teach in another one. So you can either return one department or the other one; there is no perfect solution to the problem and the fact that no implementation might be inherited (e.g. Student and Teacher could both be interfaces) doesn't seem to solve the problem to me.

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• Explaining the need to avoid horizontal scroll

  - by Bradley Herman

  I need help explaining to my boss why her design is poor on a client's website. She has no knowledge of the web, and it can be difficult as a web developer working with a woman who is a graphic designer (not even a web designer really). On a current site she has designed, an image bar "needs" to be ~1200px according to her, though it isn't necessary with the content. A quick sketch to illustrate what's going on: As you see, the banner spills out past the 960px of the content and as wide as 1200px. This creates a horizontal scroll when all the content is viewable within the 960px wide viewport. I need to make this an <img and not a CSS background because it's a jQuery slideshow that fades from image to image. I think this is a big problem because a lot of people are going to get a horizontal scroll bar imposed in their browser when they're still able to see all the relevant content. She thinks no one will notice and it'll be fine; I think it's very bad practice and confusing to the end user. How do I explain the problem to her?

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• How can I place validating constraints on my method input parameters?

  - by rcampbell

  Here is the typical way of accomplishing this goal: public void myContractualMethod(final String x, final Set<String> y) { if ((x == null) || (x.isEmpty())) { throw new IllegalArgumentException("x cannot be null or empty"); } if (y == null) { throw new IllegalArgumentException("y cannot be null"); } // Now I can actually start writing purposeful // code to accomplish the goal of this method I think this solution is ugly. Your methods quickly fill up with boilerplate code checking the valid input parameters contract, obscuring the heart of the method. Here's what I'd like to have: public void myContractualMethod(@NotNull @NotEmpty final String x, @NotNull final Set<String> y) { // Now I have a clean method body that isn't obscured by // contract checking If those annotations look like JSR 303/Bean Validation Spec, it's because I borrowed them. Unfortunitely they don't seem to work this way; they are intended for annotating instance variables, then running the object through a validator. Which of the many Java design-by-contract frameworks provide the closest functionality to my "like to have" example? The exceptions that get thrown should be runtime exceptions (like IllegalArgumentExceptions) so encapsulation isn't broken.

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• How much business logic belongs in RIA services layer?

  - by jkohlhepp

  I have been experimenting recently with Silverlight, RIA Services, and Entity Framework using .NET 4.0. I'm trying to figure out if that stack makes sense for use in any of my upcoming projects. It certainly seems like these technologies can be very productive for developing applications, but I'm struggling to decide how an application on top of this stack should be architected. The main issue I have is that in most of the demos I've seen most of the business logic ends up as DataAnnotations and custom validations in the RIA Services domain service class. This seems inappropriate to me. I view the domain service as basically a glorified web service that happens to make it easy to push information to the client. But most of what I've seen seems to orient the domain service as the main source of business logic in the application. So, my questions: What is the best location for business logic (rules, validations, behaviors, authorization) in an application using this stack? Are there any guidelines published at an architectural level for using this stack? My questions pertain to large, complex, and long-lived applications. Obviously for an application of only a few screens this is less of a concern. Edit: Another thing I meant to mention is that obviously you can make the domain service class stupid, but then you lose a lot of the automagic entity information (e.g. validations) being pushed to the client. And then if you lose that is there any point to using RIA services?

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• Naming convention for non-virtual and abstract methods

  - by eagle

  I frequently find myself creating classes which use this form (A): abstract class Animal { public void Walk() { // TODO: do something before walking // custom logic implemented by each subclass WalkInternal(); // TODO: do something after walking } protected abstract void WalkInternal(); } class Dog : Animal { protected override void WalkInternal() { // TODO: walk with 4 legs } } class Bird : Animal { protected override void WalkInternal() { // TODO: walk with 2 legs } } Rather than this form (B): abstract class Animal { public abstract void Walk(); } class Dog : Animal { public override void Walk() { // TODO: do something before walking // custom logic implemented by each subclass // TODO: walk with 4 legs // TODO: do something after walking } } class Bird : Animal { public override void Walk() { // TODO: do something before walking // custom logic implemented by each subclass // TODO: walk with 2 legs // TODO: do something after walking } } As you can see, the nice thing about form A is that every time you implement a subclass, you don't need to remember to include the initialization and finalization logic. This is much less error prone than form B. What's a standard convention for naming these methods? I like naming the public method Walk since then I can call Dog.Walk() which looks better than something like Dog.WalkExternal(). However, I don't like my solution of adding the suffix "Internal" for the protected method. I'm looking for a more standardized name. Btw, is there a name for this design pattern?

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• How to implement Session timeout in Web Server Side?

  - by Morgan Cheng

  I beheld a web framework implementing in-memory session in this way. The session object is added to Cache with timeout. When the time is out, the session is removed from Cache automatically. To protect race condition, each request should acquire lock on given session object to proceed. Each request will "touch" the session in Cache to refresh the timeout. Everything looks fine, until this scenario is discovered. Say, one operation takes a long time, longer than timeout. Another request comes and wait on session lock which is currently hold by the long-time request. Finally, the long-time request is over, it releases the lock. But, since it already takes longer time than timeout, the session object is already removed from Cache. This is obvious because the only request holding the lock doesn't have a chance to "touch" the session object in cache. The second request gets the lock but cannot retrieve the expired Session object. Oops... To fix this issue, the second request has to re-create the Session object. But, this is just like digging a buried dead body from tomb and try to bring it back to life. It causes buggy code. I'm wondering what's the best way to implement timeout in session to handle such scenario. I know that current platform must have good session mechanism. I just want to know the under-the-hood how.

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• Users in database server or database tables

  - by Batcat

  Hi all, I came across an interesting issue about client server application design. We have this browser based management application where it has many users using the system. So obvisously within that application we have an user management module within it. I have always thought having an user table in the database to keep all the login details was good enough. However, a senior developer said user management should be done in the database server layer if not then is poorly designed. What he meant was, if a user wants to use the application then a user should be created in the user table AND in the database server as a user account as well. So if I have 50 users using my applications, then I should have 50 database server user logins. I personally think having just one user account in the database server for this database was enough. Just grant this user with the allowed privileges to operate all the necessary operation need by the application. The users that are interacting with the application should have their user accounts created and managed within the database table as they are more related to the application layer. I don't see and agree there is need to create a database server user account for every user created for the application in the user table. A single database server user should be enough to handle all the query sent by the application. Really hope to hear some suggestions / opinions and whether I'm missing something? performance or security issues? Thank you very much.

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• PHPUnit and autoloaders: Determining whether code is running in test-scope?

  - by pinkgothic

  Premise I know that writing code to act differently when a test is run is hilariously bad practise, but I may've actually come across a scenario in which it may be necessary. Specifically, I'm trying to test a very specific wrapper for HTML Purifier in the Zend framework - a View Helper, to be exact. The HTML Purifier autoloader is necessary because it uses a different logic to the autoloaders we otherwise have. Problem require()-ing the autoloader at the top of my View Helper class, gives me the following in test-scope: HTML Purifier autoloader registrar is not compatible with non-static object methods due to PHP Bug #44144; Please do not use HTMLPurifier.autoload.php (or any file that includes this file); instead, place the code: spl_autoload_register(array('HTMLPurifier_Bootstrap', 'autoload')) after your own autoloaders. Replacing the require() with spl_autoload_register(array('HTMLPurifier_Bootstrap', 'autoload')) as advertised means the test runs fine, but the View Helper dies a terrible death claiming: Zend_Log[3707]: ErrorController caught LogicException "Passed array does not specify an existing static method (class 'HTMLPurifier_Bootstrap' not found)" (Our test folder structure is slightly different to our Zend folder structure by necessity.) Question(s) After tinkering with it, I'm thinking I'll need to pick an autoloader-loading depending on whether things are in the test scope or not. Do I have another option to include HTMLPurifier's autoloading routine in both cases that I'm not seeing due to tunnel vision? If not, do I have to find a means to differentiate between test-environment and production-environment this with my own code (e.g. APPLICATION_ENV) - or does PHPUnit support this godawful hackery of mine natively by setting a constant that I could check whether its been defined(), or similar shenanigans? (My Google-fu here is weak! I'm probably just doing it wrong.)

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• Why won't my program terminate?

  - by Qwertie

  I have a .NET Compact Framework app that can runs on three windows machines (Desktop windows and two WinCE machines) and on the WinCE devices, the process never terminates on exit, even if I call Application.Exit(). Besides .NET, it uses one COM component (which does everything on the UI thread). If I break into the debugger after exitting, Visual Studio shows only one thread and a completely blank call stack. What could possibly cause this? Update: My process is terminating on the desktop but not the WinCE machines. I tried to force the process to terminate with the following code, but it doesn't work: [DllImport("coredll.dll")] static extern int TerminateProcess(IntPtr hProcess, uint uExitCode); static public void ExitProcess() { if (Platform.IsWindowsCE) TerminateProcess(new IntPtr(-1), 0); Application.Exit(); } There are also supposed to be ExitProcess() and GetCurrentProcess() APIs like the following, but if I try to call them, I get EntryPointNotFoundException. Therefore I am using TerminateProcess(-1, 0) because the documentation for the desktop version of GetCurrentProcess claims that it simply returns -1. [DllImport("coredll.dll")] static extern int ExitProcess(IntPtr hProcess); [DllImport("coredll.dll")] static extern IntPtr GetCurrentProcess(); Even if I do this: static public void ExitProcess() { if (Platform.IsWindowsCE) TerminateProcess(new IntPtr(-1), 0); Application.Exit(); throw new Exception("Trying to force quit."); } A fatal error dialog appears with a helpful "Quit" button, but pushing the button still does not cause the process to terminate on either machine!

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• Explaining to boss why we need to avoid horizontal scroll

  - by Bradley Herman

  I need help explaining to my boss why her design is poor on a clients website. She has no knowledge of web and it can be difficult as a web developer working with a woman who is a graphic designer (not even a web designer really). On a current site she has designed, an image bar "needs" to be like 1200px according to her, though it isn't necessary with the content. I'll show a quick sketch to illustrate what's going on: http://imgur.com/MNGOT.jpg As you see, the banner spills out past the 960px of the content and as wide as 1200px. This creates a horizontal scroll when all the content is viewable within the 960px wide viewport. I need to make this an img and not a css background because it's a jquery slideshow that fades from image to image. I think this is a big problem because a lot of people are going to get a horizontal scroll bar imposed in their browser when they're still able to see all the relevant content. How do I help her explain it. She thinks no one will notice and it'll be fine, I think it's very bad practice and confusing to the end user. Any help?

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• jquery ajax call returning error when its not an error

  - by azz0r

  Hello, My JS Is: $(InitFavorite); function InitFavorite(){ var jList = $(".favourite_link"); var ids_to_check = {};//new Array(); $.each(jList, function () { var id = this.id; var object = id.split("_"); if (!ids_to_check[object[1]]) { ids_to_check[object[1]] = []; } ids_to_check[object[1]].push(object[0]); }); //console.log(ids_to_check); $.ajax({ type: 'POST', url: '/user/subscription/favourite-listing', data: ids_to_check, dataType: 'json', beforeSend: function(x) { if(x && x.overrideMimeType) { x.overrideMimeType("application/j-son;charset=UTF-8"); } }, error: function() { alert(1); }, success: function() { alert(2); /*$each(returned_values, function() { alert('boom'); });*/ } }); } From the ajax call, the following data is returned: {"env":"development","loggedIn":true,"translate":{}}{"Playlist":{"10":"Stop Recieving Updates For This Playlist"},"Clip":{"26":"Recieve Updates For This Clip","27":"Recieve Updates For This Clip","28":"Recieve Updates For This Clip","29":"Stop Recieving Updates For This Clip","30":"Recieve Updates For This Clip"}} However, success is never triggered, just error, despite there being no header and json being put out as the header (via zend framework). Ideas?

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• How do I use a modalViewController Identically in Two Controllers?

  - by Theory

  I'm using the Three20 TTMessageController in my app. I've figured out how to use it, adding on a bunch of other stuff (including TTMessageControllerDelegate methods and ABPeoplePickerNavigationControllerDelegate methods). It works great for me, after a bit of a struggle to figure it out. The trouble I'm having now is a design issue: I want to use it identically in two different places, including with the same delegate methods. My current approach is that I've put all the code into a single class inheriting from NSObject, called ComposerProxy, and I'm just having the two controllers that use it use the proxy, like so: ComposerProxy *proxy = [[ComposerProxy alloc] initWithController:this]; [proxy go]; The go method constructs the TTMessageController, configures it, adds it to a UINavigationController, and presents it: [self.controller presentModalViewController: navController animated: YES]; This works great, as I have all my code nicely encapsulated in ComposerProxy and I need only the above two lines anywhere I want to use it. The downside, though, is that I can't dealloc the proxy variable without getting crashes. I can't autorelease it, either: same problem. So I'm wondering if my proxy approach is a poor one. How does one normally encapsulate a bunch of behaviors like this without requiring a lot of duplicate code in the classes that use it? Do I need to add a delegate class to my ComposerProxy and make the controller responsible for dismissing the modal view controller in a hypothetical composerDidFinish method or some such? Many TIA!

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• How to have a policy class implement a virtual function?

  - by dehmann

  I'm trying to design a policy-based class, where a certain interface is implemented by the policy itself, so the class derives from the policy, which itself is a template (I got this kind of thinking from Alexandrescu's book): #include <iostream> #include <vector> class TestInterface { public: virtual void test() = 0; }; class TestImpl1 { public: void test() {std::cerr << "Impl1" << std::endl;} }; template<class TestPolicy> class Foo : public TestInterface, TestPolicy { }; Then, in the main() function, I call test() on (potentially) various different objects that all implement the same interface: int main() { std::vector<TestInterface*> foos; foos.push_back(new Foo<TestImpl1>()); foos[0]->test(); delete foos[0]; return 0; } It doesn't compile, though, because the following virtual functions are pure within ‘Foo<TestImpl1>’: virtual void TestInterface::test() I thought TestInterface::test() is implemented because we derive from TestImpl1?

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• Add multiple entities to Javascript namespace from different files

  - by Brian M. Hunt

  Given a namespaces ns used in two different files: abc.js ns = ns || (function () { foo = function() { ... }; return { abc : foo }; }()); def.js // is this correct? ns = ns || {} ns.def = ns.def || (function () { defoo = function () { ... }; return { deFoo: defoo }; }()); Is this the proper way to add def to the ns to a namespace? In other words, how does one merge two contributions to a namespace in javascript? If abc.js comes before def.js I'd expect this to work. If def.js comes before abc.js I'd expect ns.abc to not exist because ns is defined at the time. It seems there ought to be a design pattern to eliminate any uncertainty of doing inclusions with the javascript namespace pattern. I'd appreciate thoughts and input on how best to go about this sort of 'inclusion'. Thanks for reading. Brian

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• DAL Layer : EF 4.0 or Normal Data access layer with Stored Procedure

  - by Harryboy

  Hello Experts, Application : I am working on one mid-large size application which will be used as a product, we need to decide on our DAL layer. Application UI is in Silverlight and DAL layer is going to be behind service layer. We are also moving ahead with domain model, so our DB tables and domain classes are not having same structure. So patterns like Data Mapper and Repository will definitely come into picture. I need to design DAL Layer considering below mentioned factors in priority manner Speed of Development with above average performance Maintenance Future support and stability of the technology Performance Limitation : 1) As we need to strictly go ahead with microsoft, we can not use NHibernate or any other ORM except EF 4.0 2) We can use any code generation tool (Should be Open source or very cheap) but it should only generate code in .Net, so there would not be any licensing issue on per copy basis. Questions I read so many articles about EF 4.0, on outset it looks like that it is still lacking in features from NHibernate but it is considerably better then EF 1.0 So, Do you people feel that we should go ahead with EF 4.0 or we should stick to ADO .Net and use any code geneartion tool like code smith or any other you feel best Also i need to answer questions like what time it will take to port application from EF 4.0 to ADO .Net if in future we stuck up with EF 4.0 for some features or we are having serious performance issue. In reverse case if we go ahead and choose ADO .Net then what time it will take to swith to EF 4.0 Lastly..as i was going through the article i found the code only approach (with POCO classes) seems to be best suited for our requirement as switching is really easy from one technology to other. Please share your thoughts on the same and please guide on the above questions

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• Advice on designing and building distributed application to track vehicles

  - by dario-g

  I'm working on application for tracking vehicles. There will be about 10k or more vehicles. Each will be sending ~250bytes in each minute. Data contains gps location and everything from CAN Bus (every data that we can read from vehicle computer and dashboard). Data are sent by GSM/GPRS (using UDP protocol). Estimated rows with this data per day is ~2000k. I see there 3 main blocks. 1. Multithreaded Socket Server (MSS) - I have it. MSS stores received data to the queue (using NServiceBus). 2. Rule Processor Server (RPS) - this is core of this system. This block is responsible for parsing received data, storing in the database, processing rules, sending messages to Notifier Server (this will be sending e-mails/sms texts). Rule example. As I said between received bytes there will be information about current speed. When speed will be above 120 then: show alert in web application for specified users, send e-mail, send sms text. (There can be more than one instance of RPS). 3. Web application - allows reporting and defining rules by users, monitoring alerts, etc. I'm looking for advice how to design communication between RPS and Web application. Some questions: - Should Web application and RPS have separated databases or one central database will be enough? I have one domain model in web application. If there will be one central database then can I use the same model (objects) on RPS? So, how to send changed rules to RPS? I try to decouple this blocks as much as possible. I'm planning to create different instance of application for each client (each client will have separated database). One client will be have 10k vehicles, others only 100 vehicles.

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• Update one-to-many EntityKey using Foreign Key

  - by User.Anonymous

  To use by the easiest way Entity Framework, I use partial class to add Foreign Key on most important Entities Model. For example, I have an Entity "CONTACT" which have "TITLE", "FUNCTION" and others. When I update a CONTACT, with this code, Foreign Key are automatically updated : public int? TitId { get { if (this.TITLE_TIT != null) return TITLE_TIT.TIT_ID; return new Nullable<int>(); } set { this.TITLE_TITReference.EntityKey = new System.Data.EntityKey("Entities.TITLE_TIT", "TIT_ID", value); } } But I have a join with ACTIVITY, that can have many CONTACT, and I don't know how to update EntityKey on setters. public IEnumerable<EntityKeyMember> ActId { get { List<EntityKeyMember> lst = new List<EntityKeyMember>(); if (this.ACT_CON2 != null) { foreach (ACT_CON2 id in this.ACT_CON2.ToList()) { EntityKeyMember key = new EntityKeyMember(id.CON_ID.ToString(),id.ACT_ID); lst.Add(key); } } return lst; } set { this.ACT_CON2.EntityKey = new System.Data.EntityKey("Entities.ACT_CON2", value); } } How set many EntityKey ? Thank you.

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• Using Hidden Markov Model for designing AI mp3 player

  - by Casper Slynge

  Hey guys. Im working on an assignment, where I want to design an AI for a mp3 player. The AI must be trained and designed with the use of a HMM method. The mp3 player shall have the functionality of adapting to its user, by analyzing incoming biological sensor data, and from this data the mp3 player will choose a genre for the next song. Given in the assignment is 14 samples of data: One sample consist of Heart Rate, Respiration, Skin Conductivity, Activity and finally the output genre. Below is the 14 samples of data, just for you to get an impression of what im talking about. Sample HR RSP SC Activity Genre S1 Medium Low High Low Rock S2 High Low Medium High Rock S3 High High Medium Low Classic S4 High Medium Low Medium Classic S5 Medium Medium Low Low Classic S6 Medium Low High High Rock S7 Medium High Medium Low Classic S8 High Medium High Low Rock S9 High High Low Low Classic S10 Medium Medium Medium Low Classic S11 Medium Medium High High Rock S12 Low Medium Medium High Classic S13 Medium High Low Low Classic S14 High Low Medium High Rock My time of work regarding HMM is quite low, so my question to you is if I got the right angle on the assignment. I have three different states for each sensor: Low, Medium, High. Two observations/output symbols: Rock, Classic In my own opinion I see my start probabilities as the weightened factors for either a Low, Medium or High state in the Heart Rate. So the ideal solution for the AI is that it will learn these 14 sets of samples. And when a users sensor input is received, the AI will compare the combination of states for all four sensors, with the already memorized samples. If there exist a matching combination, the AI will choose the genre, and if not it will choose a genre according to the weightened transition probabilities, while simultaniously updating the transition probabilities with the new data. Is this a right approach to take, or am I missing something ? Is there another way to determine the output probability (read about Maximum likelihood estimation by EM, but dont understand the concept)? Best regards, Casper

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• Zend Sessions problem with IE8

  - by Emil

  I'm running a Zend Framework powered website and it seems to have serious problems with sessions. I have a 5 step process where I save the form data in the session between the steps and then save it into the database on the last step. When we built the site sometimes the session just went away and forced us to restart. Now it seems to work again but recently we discovered an issue with Internet Explorer 8. It fails between step 2 - 3 and forgets the session. It works fine in IE6, IE7, FF, Chrome, Safari and even in my mobile web browser (SE P1). We're storing our sessions in the database and if I deactivate the session db handler it works. What's the difference between using the database and not using it for sessions? Do I loose something if I switch back? Bootstrap: /* Start session */ $saveHandler = new Zend_Session_SaveHandler_DbTable(array( 'name' => 'sessions', 'primary' => 'id', 'modifiedColumn' => 'modified', 'dataColumn' => 'data', 'lifetimeColumn' => 'lifetime' )); Zend_Session::rememberMe((int) $config->session->lifetime); $saveHandler->setLifetime((int) $config->session->lifetime) ->setOverrideLifetime(true); Zend_Session::setSaveHandler($saveHandler); Zend_Session::start(); and in my step controller $session = new Zend_Session_Namespace('wizard'); Then I'm just working with $session saving data in a stdClass in $session.

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• SQL Concurrent test update question

  - by ptoinson

  Howdy Folks, I have a SQLServer 2008 database in which I have a table for Tags. A tag is just an id and a name. The definition of the tags table looks like: CREATE TABLE [dbo].[Tag]( [ID] [int] IDENTITY(1,1) NOT NULL, [Name] [varchar](255) NOT NULL CONSTRAINT [PK_Tag] PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ) Name is also a unique index. further I have several processes adding data to this table at a pretty rapid rate. These processes use a stored proc that looks like: ALTER PROC [dbo].[lg_Tag_Insert] @Name varchar(255) AS DECLARE @ID int SET @ID = (select ID from Tag where Name=@Name ) if @ID is null begin INSERT Tag(Name) VALUES (@Name) RETURN SCOPE_IDENTITY() end else begin return @ID end My issues is that, other than being a novice at concurrent database design, there seems to be a race condition that is causing me to occasionally get an error that I'm trying to enter duplicate keys (Name) into the DB. The error is: Cannot insert duplicate key row in object 'dbo.Tag' with unique index 'IX_Tag_Name'. This makes sense, I'm just not sure how to fix this. If it where code I would know how to lock the right areas. SQLServer is quite a different beast. First question is what is the proper way to code this 'check, then update pattern'? It seems I need to get an exclusive lock on the row during the check, rather than a shared lock, but it's not clear to me the best way to do that. Any help in the right direction will be greatly appreciated. Thanks in advance.

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• How do I add ROW_NUMBER to a LINQ query or Entity?

  - by Whozumommy

  I'm stumped by this easy data problem. I'm using the Entity framework and have a database of products. My results page returns a paginated list of these products. Right now my results are ordered by the number of sales of each product, so my code looks like this: return Products.OrderByDescending(u => u.Sales.Count()); This returns an IQueryable dataset of my entities, sorted by the number of sales. I want my results page to show the rank of each product (in the dataset). My results should look like this: Page #1 1. Bananas 2. Apples 3. Coffee Page #2 4. Cookies 5. Ice Cream 6. Lettuce I'm expecting that I just want to add a column in my results using the SQL ROW_NUMBER variable...but I don't know how to add this column to my results datatable. My resulting page does contain a foreach loop, but since I'm using a paginated set I'm guessing using that number to fake a ranking number would NOT be the best approach. So my question is, how do I add a ROW_NUMBER column to my query results in this case?

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• Zend/PHP: How to disable webpage behind popup ?

  - by NAVEED

  I am working on zend framework, PHP and jQuery. I am working on popups sometimes. When any popup is open on the screen, we can still clicks links on webpage behind popup which causes some unexpected behaviour. How can I disable a webpage behind popup. I have seen some web application in which when popup appears then webpage behind popup become shady. I have read some tutorial about this. In each tutorial a link is used to open a dialog and an special attribute is added in for modal. But I have a different case I have to open dialog on some condition in action. I check a condition in action after post like this: $form = new Edit_Form( ); $this->view->form = $form; $this->view->form->setAction($this->view->url()); $request = $this->getRequest(); if ( $request->isPost() ) { $values = $request->getParams(); if( $values['edit'] ) { $this->view->openEditBox(); } } Now check in view to see that it should open an edit pop or not: if( $this->openEditBox ){ $jsonOutput ['content'] = '<div class="DialogBox" title="Edit">' . $this->form->render() . '</div>'; echo Zend_Json::encode($jsonOutput); } Any Idea? Thanks

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• Horizontally align rows in multiple tables using web user control

  - by goku_da_master

  I need to align rows in different tables that are layed out horizontally. I'd prefer to put the html code in a single web user control so I can create as many instances of that control as I want and lay them out horizontally. The problem is, the text in the rows needs to wrap. So some rows may expand vertically and some may not (see the example below). When that happens, the rows in the other tables aren't aligned horizontally. I know I can accomplish all this by using a single table, but that would mean I'd have to duplicate the name, address and phone html code instead of dynamically creating new instances of my user control (in reality there are many more fields than this, but I'm keeping it simple). Is there any way to do this whether with div's, tables or something else? Here's the problem: Mary Jane's address field expands 2 lines, causing her phone field to not align properly with John's and Bob's. Name: John Doe Name: Mary Jane Name: Bob Smith Address: 123 broadway Address: Some really long address Address: Short address Phone: 123-456 that takes up multiple lines Phone: 111-2222 Phone: 456-789 I'm not restricted in any way how to do this (other than using asp.net), but I'd prefer to use a single web control that I instantiate X times at design time (in this example, it's 3 times). I'm using VS2008, and .Net 3.5

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