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  • Is a full html page needed when loading a page with jQuery mobile?

    - by Vincent Hiribarren
    I am currently looking at jQuery mobile and its system of loading web pages with XmlHttpRequest. Thanks to that it is possible to automatically perform transition animations between two pages, for instance. However, something is not clear to me. If I understand correctly, each new page of a jQuery mobile powered website is injected in the DOM of the initial web page. The documentation of jQuery mobile even tells that because of this mechanism, the <title> tag of new webpages are not taken into account. So, in a way, if my initial webpage A.html loads a page B.html, I would tend to think that the webpage B.html does not need to have a full HTML grammar with the <html>, <head> or <body> tags. My page B.html could directly begin with a <div> element. Am I right?Is a full html page needed when loading a HTML page with jQuery mobile?What are the pros and cons about having a webpage with a wrong/truncated HTML syntax (appart that this page should not be accessed directly but through the main page)?

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  • Invoking a method overloaded where all arguments implement the same interface

    - by double07
    Hello, My starting point is the following: - I have a method, transform, which I overloaded to behave differently depending on the type of arguments that are passed in (see transform(A a1, A a2) and transform(A a1, B b) in my example below) - All these arguments implement the same interface, X I would like to apply that transform method on various objects all implementing the X interface. What I came up with was to implement transform(X x1, X x2), which checks for the instance of each object before applying the relevant variant of my transform. Though it works, the code seems ugly and I am also concerned of the performance overhead for evaluating these various instanceof and casting. Is that transform the best I can do in Java or is there a more elegant and/or efficient way of achieving the same behavior? Below is a trivial, working example printing out BA. I am looking for examples on how to improve that code. In my real code, I have naturally more implementations of 'transform' and none are trivial like below. public class A implements X { } public class B implements X { } interface X { } public A transform(A a1, A a2) { System.out.print("A"); return a2; } public A transform(A a1, B b) { System.out.print("B"); return a1; } // Isn't there something better than the code below??? public X transform(X x1, X x2) { if ((x1 instanceof A) && (x2 instanceof A)) { return transform((A) x1, (A) x2); } else if ((x1 instanceof A) && (x2 instanceof B)) { return transform((A) x1, (B) x2); } else { throw new RuntimeException("Transform not implemented for " + x1.getClass() + "," + x2.getClass()); } } @Test public void trivial() { X x1 = new A(); X x2 = new B(); X result = transform(x1, x2); transform(x1, result); }

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  • Cocos2d and MPMoviePlayerViewController - NSNotificationCenter not working

    - by digi_0315
    I'm using cocos2d with MPMoviePlayerViewController class, but when I tryed to catch notification status when the movie is finished I got this error: Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFString movieFinishedCallback]: unrecognized selector sent to instance 0x5d23730' my playVideoController.m are: @implementation PlayVideoViewController +(id) scene{ CCScene *scene = [CCScene node]; CCLayer *layer = [credits node]; [scene addChild: layer]; return scene; } -(id)initWithPath:(NSString *)moviePath{ if ((self = [super init])){ movieURL = [NSURL fileURLWithPath:moviePath]; [movieURL retain]; playerViewController = [[MPMoviePlayerViewController alloc] initWithContentURL:movieURL]; player = [playerViewController moviePlayer]; [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(movieFinishedCallback) name:MPMoviePlayerPlaybackDidFinishNotification object:player]; [[[CCDirector sharedDirector] openGLView] addSubview:playerViewController.view]; [player play]; } return self; } -(void)movieFinishedCallback{ CCLOG(@"video finished!!"); } in .h: #import <UIKit/UIKit.h> #import "cocos2d.h" #import <MediaPlayer/MediaPlayer.h> @interface PlayVideoViewController : CCLayer { NSURL *movieURL; MPMoviePlayerViewController *playerViewController; MPMoviePlayerController *player; } +(id) scene; @end and I call it in appDelegate.m: - (void) applicationDidFinishLaunching:(UIApplication*)application { CC_DIRECTOR_INIT(); CCDirector *director = [CCDirector sharedDirector]; [director setDeviceOrientation:kCCDeviceOrientationLandscapeLeft]; EAGLView *glView = [director openGLView]; [glView setMultipleTouchEnabled:YES]; [CCTexture2D setDefaultAlphaPixelFormat:kTexture2DPixelFormat_RGBA8888];//kEAGLColorFormatRGBA8 NSString *path = [[NSBundle mainBundle] pathForResource:@"intro" ofType:@"mov" inDirectory:nil]; vi ewController = [[[PlayVideoViewController alloc] initWithPath:path] autorelease]; } what i'm doing wrong? anyone can help me please?? I'm try to solve it since a lot of hours ago but I can't!

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  • Axis2 SOAP Envelope Header Information

    - by BigZig
    I'm consuming a web service that places an authentication token in the SOAP envelope header. It appears (through looking at the samples that came with the WS WSDL) that if the stub is generated in .NET, this header information is exposed through a member variable in the stub class. However, when I generate my Axis2 java stub using WSDL2Java it doesn't appear to be exposed anywhere. What is the correct way to extract this information from the SOAP envelope header? WSDL: http://www.vbar.com/zangelo/SecurityService.wsdl C# Sample: using System; using SignInSample.Security; // web service using SignInSample.Document; // web service namespace SignInSample { class SignInSampleClass { [STAThread] static void Main(string[] args) { // login to the Vault and set up the document service SecurityService secSvc = new SecurityService(); secSvc.Url = "http://localhost/AutodeskDM/Services/SecurityService.asmx"; secSvc.SecurityHeaderValue = new SignInSample.Security.SecurityHeader(); secSvc.SignIn("Administrator", "", "Vault"); DocumentServiceWse docSvc = new DocumentServiceWse(); docSvc.Url = "http://localhost/AutodeskDM/Services/DocumentService.asmx"; docSvc.SecurityHeaderValue = new SignInSample.Document.SecurityHeader(); docSvc.SecurityHeaderValue.Ticket = secSvc.SecurityHeaderValue.Ticket; docSvc.SecurityHeaderValue.UserId = secSvc.SecurityHeaderValue.UserId; } } } The sample illustrates what I'd like to do. Notice how the secSvc instance has a SecurityHeaderValue member variable that is populated after a successful secSvc.SignIn() invocation. Here's some relevant API documentation regarding the SignIn method: Although there is no return value, a successful sign in will populate the SecurityHeaderValue of the security service. The SecurityHeaderValue information is then used for other web service calls.

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  • C++: parsing with simple regular expression or shoud I use sscanf?

    - by Helltone
    I need to parse a string like func1(arg1, arg2); func2(arg3, arg4);. It's not a very complex parsing problem, so I would prefer to avoid resorting to flex/bison or similar utilities. My first approch was to try to use POSIX C regcomp/regexec or Boost implementation of C++ std::regex. I wrote the following regular expression, which does not work (I'll explain why further on). "^" "[ ;\t\n]*" "(" // (1) identifier "[a-zA-Z_][a-zA-Z0-9_]*" ")" "[ \t\n]*" "(" // (2) non-marking "\[" "(" // (3) non-marking "[ \t]*" "(" // (4..n-1) argument "[a-zA-Z0-9_]+" ")" "[ \t\n]*" "," ")*" "[ \t\n]*" "(" // (n) last argument "[a-zA-Z0-9_]+" ")" "]" ")?" "[ \t\n]*" ";" Note that the group 1 captures the identifier and groups 4..n-1 are intended to capture arguments except the last, which is captured by group n. When I apply this regex to, say func(arg1, arg2, arg3) the result I get is an array {func, arg2, arg3}. This is wrong because arg1 is not in it! The problem is that in the standard regex libraries, submarkings only capture the last match. In other words, if you have for instance the regex "((a*|b*))*" applied on "babb", the results of the inner match will be bb and all previous captures will have been forgotten. Another thing that annoys me here is that in case of error there is no way to know which character was not recognized as these functions provide very little information about the state of the parser when the input is rejected. So I don't know if I'm missing something here... In this case should I use sscanf or similar instead? Note that I prefer to use C/C++ standard libraries (and maybe boost).

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  • How do I create a class repository in Java and do I really need it?

    - by Roman
    I have a large number of objects which are identified by names (strings). So, I would like to have a kind of mapping from object name to the class instances. I was told that in this situation I can use a "repository" class which works like that: Server myServer = ServerRepository.getServer("NameOfServer"); So, if there is already an object (sever) with the "NameOfServer" it will be returned by the "getServer". If such an object does not exist yet, it will be created and returned by the "getServer". So, my question is how to program such a "repository" class? In this class I have to be able to check if there is an instance of a given class such that it has a given value of a given field. How can I do it? I need to have a kind of loop over all existing object of a given class? Another part of my question is why I cannot use associative arrays (associative container, map, mapping, dictionary, finite map)? (I am not sure how do you call it in Java) In more details, I have an "array" which maps names of objects to objects. So, whenever I create a new object, I add a new element to the array: myArray["NameOfServer"] = new Server("NameOfServer").

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  • c# multi inheritance

    - by user326839
    So ive got a base class which requires a Socket: class Sock { public Socket s; public Sock(Socket s) { this.s = s; } public virtual void Process(byte[] data) { } ... } then ive got another class. if a new socket gets accepted a new instance of this class will be created: class Game : Sock { public Random Random = new Random(); public Timerr Timers; public Test Test; public Game(Socket s) : base(s) { } public static void ReceiveNewSocket(object s) { Game Client = new Game((Socket)s); Client.Start(); } public override void Process(byte[] buf) { Timers = new Timerr(s); Test = new Test(s); Test.T(); } } in the Sock class ive got a virtual function that gets overwritten by the Game class.(Process function) in this function im calling a function from the Test Class(Test+ Timerr Class: class Test : Game { public Test(Socket s) : base(s) { } public void T() { Console.WriteLine(Random.Next(0, 10)); Timers.Start(); } } class Timerr : Game { public Timerr(Socket s) : base(s) { } public void Start() { Console.WriteLine("test"); } } ) So in the Process function im calling a function in Test. And in this function(T) i need to call a function from the Timerr Class.But the problem is its always NULL , although the constructor is called in Process. And e.g. the Random Class can be called, i guess its because its defined with the constructor.: public Random Random = new Random(); and thats why the other classes(without a constructor): public Timerr Timers; public Test Test; are always null in the inherited class Test.But its essentiel that i call other Methods of other classes in this function.How could i solve that?

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  • Transaction to find an entity - locks all entities of that type?

    - by user246114
    Hi, Reading the docs for transactions: http://code.google.com/appengine/docs/java/datastore/transactions.html An example provided shows one way to make an instance of an object: try { tx.begin(); Key k = KeyFactory.createKey("SalesAccount", id); try { account = pm.getObjectById(Employee.class, k); } catch (JDOObjectNotFoundException e) { account = new SalesAccount(); account.setId(id); } ... When the above transaction gets executed, it will probably block all other write attempts on Account objects? I'm wondering because I'd like to have a user signup which checks for a username or email already in use: tx.begin(); "select from User where mUsername == str1 LIMIT 1"; if (count > 0) { throw new Exception("username already in use!"); } "select from User where mEmail == str1 LIMIT 1"; if (count > 0) { throw new Exception("email already in use!"); } pm.makePersistent(user(username, email)); // ok. tx.commit(); but the above would be even more time consuming I think, making an even worse bottleneck? Am I understanding what will happen correctly? Thanks

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  • SQL different joins not making any difference to result

    - by Chrissi
    I'm trying to write a quick (ha!) program to organise some of my financial information. What I ideally want is a query that will return all records with financial information in them from TableA. There should be one row for each month, but in instances where there were no transactions for a month there will be no record. I get results like this: SELECT Period,Year,TotalValue FROM TableA WHERE Year='1997' Result: Period Year TotalValue 1 1997 298.16 2 1997 435.25 4 1997 338.37 8 1997 336.07 9 1997 578.97 11 1997 361.23 By joining on a table (well a View in this instance) which just contains a field Period with values from 1 to 12, I expect to get something like this: SELECT p.Period,a.Year,a.TotalValue FROM Periods AS p LEFT JOIN TableA AS a ON p.Period = a.Period WHERE Year='1997' Result: Period Year TotalValue 1 1997 298.16 2 1997 435.25 3 NULL NULL 4 1997 338.37 5 NULL NULL 6 NULL NULL 7 NULL NULL 8 1997 336.07 9 1997 578.97 10 NULL NULL 11 1997 361.23 12 NULL NULL What I'm actually getting though is the same result no matter how I join it (except CROSS JOIN which goes nuts, but it's really not what I wanted anyway, it was just to see if different joins are even doing anything). LEFT JOIN, RIGHT JOIN, INNER JOIN all fail to provide the NULL records I am expecting. Is there something obvious that I'm doing wrong in the JOIN? Does it matter that I'm joining onto a View?

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  • Unable to get data from a WCF client

    - by Scott
    I am developing a DLL that will provide sychronized time stamps to multiple applications running on the same machine. The timestamps are altered in a thread that uses a high performance timer and a scalar to provide the appearance of moving faster than real-time. For obvious reasons I want only 1 instance of this time library, and I thought I could use WCF for the other processes to connect to this and poll for timestamps whenever they want. When I connect however I never get a valid time stamp, just an empty DateTime. I should point out that the library does work. The original implementation was a single DLL that each application incorporated and each one was synced using windows messages. I'm fairly sure it has something to do with how I'm setting up the WCF stuff, to which I am still pretty new. Here are the contract definitions: public interface ITimerCallbacks { [OperationContract(IsOneWay = true)] void TimerElapsed(String id); } [ServiceContract(SessionMode = SessionMode.Required, CallbackContract = typeof(ITimerCallbacks))] public interface ISimTime { [OperationContract] DateTime GetTime(); } Here is my class definition: [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)] public class SimTimeServer: ISimTime The host setup: // set up WCF interprocess comms host = new ServiceHost(typeof(SimTimeServer), new Uri[] { new Uri("net.pipe://localhost") }); host.AddServiceEndpoint(typeof(ISimTime), new NetNamedPipeBinding(), "SimTime"); host.Open(); and the implementation of the interface function server-side: public DateTime GetTime() { if (ThreadMutex.WaitOne(20)) { RetTime = CurrentTime; ThreadMutex.ReleaseMutex(); } return RetTime; } Lastly the client-side implementation: Callbacks myCallbacks = new Callbacks(); DuplexChannelFactory pipeFactory = new DuplexChannelFactory(myCallbacks, new NetNamedPipeBinding(), new EndpointAddress("net.pipe://localhost/SimTime")); ISimTime pipeProxy = pipeFactory.CreateChannel(); while (true) { string str = Console.ReadLine(); if (str.ToLower().Contains("get")) Console.WriteLine(pipeProxy.GetTime().ToString()); else if (str.ToLower().Contains("exit")) break; }

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  • Integrate OpenId into an existing site

    - by Andrea
    I have a working web application which already has a login and registration system. I'm looking for some advice on how to do it. Until now, users have a username, an email, a password and some optional fields. The registrartion is the usual process with email confirmation. Now I'd like to allow users to use OpenId. So I have added an openid field to the table. There are two different login forms, and users which are already registered can add their openid info and use either login form. The problem is with new users who come on the site for the first time and try to login with OpenId. I create a new user for them, and I don't need a password, but still I need at least a username, which is used on the site (I'm not sure if the email is needed). So my problems are: 1) How do I manage validation? Some fields are required for some users, (e.g. a password) but not for some others. I mean, I can do this, but it immediately gets messy. 2) Should I ask for a username and email on the first OpenId login? On the one hand I'd say yes, but I fear this vanishes the advantages of using OpenId, that is, not having to provide details. 3) I could get the details via SReg or AttributeExchange, but most providers have a bad support for those. For instance my Gmail OpenId account does not tell the email (!). Is there some place to learn more about the current support for these extensions?

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  • Ad distribution problem: an optimal solution?

    - by Mokuchan
    I'm asked to find a 2 approximate solution to this problem: You’re consulting for an e-commerce site that receives a large number of visitors each day. For each visitor i, where i € {1, 2 ..... n}, the site has assigned a value v[i], representing the expected revenue that can be obtained from this customer. Each visitor i is shown one of m possible ads A1, A2 ..... An as they enter the site. The site wants a selection of one ad for each customer so that each ad is seen, overall, by a set of customers of reasonably large total weight. Thus, given a selection of one ad for each customer, we will define the spread of this selection to be the minimum, over j = 1, 2 ..... m, of the total weight of all customers who were shown ad Aj. Example Suppose there are six customers with values 3, 4, 12, 2, 4, 6, and there are m = 3 ads. Then, in this instance, one could achieve a spread of 9 by showing ad A1 to customers 1, 2, 4, ad A2 to customer 3, and ad A3 to customers 5 and 6. The ultimate goal is to find a selection of an ad for each customer that maximizes the spread. Unfortunately, this optimization problem is NP-hard (you don’t have to prove this). So instead give a polynomial-time algorithm that approximates the maximum spread within a factor of 2. The solution I found is the following: Order visitors values in descending order Add the next visitor value (i.e. assign the visitor) to the Ad with the current lowest total value Repeat This solution actually seems to always find the optimal solution, or I simply can't find a counterexample. Can you find it? Is this a non-polinomial solution and I just can't see it?

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  • What is the proper way to use a Logger in a Serializable Java class?

    - by Tim Visher
    I have the following (doctored) class in a system I'm working on and Findbugs is generating a SE_BAD_FIELD warning and I'm trying to understand why it would say that before I fix it in the way that I thought I would. The reason I'm confused is because the description would seem to indicate that I had used no other non-serializable instance fields in the class but bar.model.Foo is also not serializable and used in the exact same way (as far as I can tell) but Findbugs generates no warning for it. import bar.model.Foo; import java.io.File; import java.io.Serializable; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class Demo implements Serializable { private final Logger logger = LoggerFactory.getLogger(this.getClass()); private final File file; private final List<Foo> originalFoos; private Integer count; private int primitive = 0; public Demo() { for (Foo foo : originalFoos) { this.logger.debug(...); } } ... } My initial blush at a solution is to get a logger reference from the factory right as I use it: public DispositionFile() { Logger logger = LoggerFactory.getLogger(this.getClass()); for (Foo foo : originalFoos) { this.logger.debug(...); } } That doesn't seem particularly efficient, though. Thoughts?

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  • routing mvc on the web

    - by generic_noob
    Hi, I was wondering if anyone could possibly provide me some advice on how i could improve the routing (and/or architecture) to each 'section' of my application. (I'm writing in PHP5, and trying to use strict MVC) Basically, I have a generic index page for the app, and that will spew out boilerplate stuff like jquery and the css etc. and it also generates the main navidation for the entire site, but i'm unsure about the best approach to connect the 'main menu' items(hyperlinks) with their associated controllers. Up until now I have been appending strings into the url and using a 'switch' statement to branch to the correct controller(and view) by extracting the strings back out of '$GET[]' to let it execute the code for the corrosponding action. for instance if i had a basic crud system for customer data, the url to edit a customers details would look like 'www.example.com/index.php?page=customer&action=edit&id=4'. I'm worried that there is a security concern by doing it this way, and i'm not sure of an alternative to branch the main 'index.php' file to the correct controller for each action once the user has clicked the link. Would it be better to use mod_rewrite to disguise the controllers names? or to create a similar system to the ASP MVC framework, where there is a seperate routing system where each url is filtered to get the associated controller? Cheers!

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  • Make Trac use a Drupal user database for authentication

    - by denisw
    I am trying to set up a Trac instance as a complement to a Drupal site and would like to give users the possibility to use their Drupal account in Trac, too, ideally in a single sign-on fashion (if the user is already logged into Drupal, he is automatically logged into Trac). The question now is how to accomplish this. I have found a plugin named DrupalIntegration which seems to implement that functionality; however, it is poorly documented - in fact, not documented at all. I managed to install it, but don't know how to configure it. Here is what I came up with from looking at the source code and the documentation of the AccountManager plugin (on which DrupalIntegration depends): [components] trac.web.auth.loginmodule = disabled acct_mgr.api = enabled acct_mgr.web_ui.LoginModule = enabled acct_mgr.web_ui.RegistrationModule = disabled TracDrupalIntegration.DrupalIntegration = enabled [account-manager] drupal_database = mysql://<usernam>:<password>@localhost/<db> password_store = DrupalIntegration (<username>, <password> and <db> are naturally substituted with the correct data). While the Trac log says: 2010-12-18 10:54:09,570 Trac[loader] DEBUG: Loading TracDrupalIntegration from /usr/lib/python2.5/site-packages/TracDrupalIntegration-0.1-py2.5.egg this doesn't seem to work: trying to log in with a Drupal username / password results in an "Invalid username or password" error. Has someone used the DrupalIntegration and can point out to me what I did wrong? Or is there any other approach you know (or even have used in the past) to integrate Drupal and Trac that way?

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  • MUD (game) design concept question about timed events.

    - by mudder
    I'm trying my hand at building a MUD (multiplayer interactive-fiction game) I'm in the design/conceptualizing phase and I've run into a problem that I can't come up with a solution for. I'm hoping some more experienced programmers will have some advice. Here's the problem as best I can explain it. When the player decides to perform an action he sends a command to the server. the server then processes the command, determines whether or not the action can be performed, and either does it or responds with a reason as to why it could not be done. One reason that an action might fail is that the player is busy doing something else. For instance, if a player is mid-fight and has just swung a massive broadsword, it might take 3 seconds before he can repeat this action. If the player attempts to swing again to soon, the game will respond indicating that he must wait x seconds before doing that. Now, this I can probably design without much trouble. The problem I'm having is how I can replicate this behavior from AI creatures. All of the events that are being performed by the server ON ITS OWN, aka not as an immediate reaction to something a player has done, will have to be time sensitive. Some evil monster has cast a spell on you but must wait 30 seconds before doing it again... I think I'll probably be adding all these events to some kind of event queue, but how can I make that event queue time sensitive?

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  • How do I initialize the controls in an InsertItemTemplate?

    - by Slauma
    I have - for instance - an asp:FormView which supports Read, Insert, Update, Delete and is bound to a DataSource: <asp:FormView ID="FormView1" runat="server" DataSourceID="ObjectDataSource1" > <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("MyText") %>' /> </ItemTemplate> <EditItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("MyText") %>' /> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("MyText") %>' /> </InsertItemTemplate> </asp:FormView> If I am in Read-Mode or Edit-Mode the control is initialized with the property MyText of the current object which is bound to the FormView. But when I go to Insert-Mode I do not have a "current object" (FormView1.DataItem is indeed null) and the controls are empty. If I want to have my TextBox control initialized with a specific value how can I do that? In which event can I hook in to set default values to the controls in the InsertItemTemplate? Especially I have in mind using an ObjectDataSource. I was expecting that the InsertItemTemplate is initialized with a business object which underlies my ObjectDataSource and which is created by the ASP.NET framework simply by using its default constructor when the InsertItemTemplate gets activated. In the default constructor I would init the class members to the default values I'd like to have in my controls of the InsertItemTemplate. But unfortunately that's not the case: No "default" object is created and bound to the FormView. So it seems I have to initialize all controls separately or to create the default object manually and bind it to the InsertItemTemplate of the FormView. But how and where can I do that? Thanks in advance!

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  • How are declared private ivars different from synthesized ivars?

    - by lemnar
    I know that the modern Objective-C runtime can synthesize ivars. I thought that synthesized ivars behaved exactly like declared ivars that are marked @private, but they don't. As a result, come code compiles only under the modern runtime that I expected would work on either. For example, a superclass: @interface A : NSObject { #if !__OBJC2__ @private NSString *_c; #endif } @property (nonatomic, copy) NSString *d; @end @implementation A @synthesize d=_c; - (void)dealloc { [_c release]; [super dealloc]; } @end and a subclass: @interface B : A { #if !__OBJC2__ @private NSString *_c; #endif } @property (nonatomic, copy) NSString *e; @end @implementation B @synthesize e=_c; - (void)dealloc { [_c release]; [super dealloc]; } @end A subclass can't have a declared ivar with the same name as one of its superclass's declared ivars, even if the superclass's ivar is private. This seems to me like a violation of the meaning of @private, since the subclass is affected by the superclass's choice of something private. What I'm more concerned about, however, is how should I think about synthesized ivars. I thought they acted like declared private ivars, but without the fragile base class problem. Maybe that's right, and I just don't understand the fragile base class problem. Why does the above code compile only in the modern runtime? Does the fragile base class problem exist when all superclass instance variables are private?

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  • MySQL - Structure for Permissions to Objects

    - by Kerry
    What would be an ideal structure for users permissions of objects. I've seen many related posts for general permissions, or what sections a user can access, which consists of a users, userGroups and userGroupRelations or something of that nature. In my system there are many different objects that can get created, and each one has to be able to be turned on or off. For instance, take a password manager that has groups and sub groups. Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 Group 7 Group 8 Group 9 Group 10 Each group can contain a set of passwords. A user can be given read, write, edit and delete permissions to any group. More groups can get created at any point in time. If someone has permission to a group, I should be able to make him have permissions to all sub groups OR restrict it to just that group. My current thought is to have a users table, and then a permissions table with columns like: permission_id (int) PRIMARY_KEY user_id (int) INDEX object_id (int) INDEX type (varchar) INDEX read (bool) write (bool) edit (bool) delete (bool) This has worked in the past, but the new system I'm building needs to be able to scale rapidly, and I am unsure if this is the best structure. It also makes the idea of having someone with all subgroup permissions of a group more difficult. So, as a question, should I use the above structure? Or can someone point me in the direction of a better one?

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  • Django ManyToMany Membership errors making associations

    - by jmitchel3
    I'm trying to have a "member admin" in which they have hundreds of members in the group. These members can be in several groups. Admins can remove access for the member ideally in the view. I'm having trouble just creating the group. I used a ManytoManyField to get started. Ideally, the "member admin" would be able to either select existing Users OR it would be able to Add/Invite new ones via email address. Here's what I have: #views.py def membership(request): group = Group.objects.all().filter(user=request.user) GroupFormSet = modelformset_factory(Group, form=MembershipForm) if request.method == 'POST': formset = GroupFormSet(request.POST, request.FILES, queryset=group) if formset.is_valid(): formset.save(commit=False) for form in formset: form.instance.user = request.user formset.save() return render_to_response('formset.html', locals(), context_instance=RequestContext(request)) else: formset= GroupFormSet(queryset=group) return render_to_response('formset.html', locals(), context_instance=RequestContext(request)) #models.py class Group(models.Model): name = models.CharField(max_length=128) members = models.ManyToManyField(User, related_name='community_members', through='Membership') user = models.ForeignKey(User, related_name='community_creator', null=True) def __unicode__(self): return self.name class Membership(models.Model): member = models.ForeignKey(User, related_name='user_membership', blank=True, null=True) group = models.ForeignKey(Group, related_name='community_membership', blank=True, null=True) date_joined = models.DateField(auto_now=True, blank=True, null=True) class Meta: unique_together = ('member', 'group') Any ideas? Thank you for your help.

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  • Do I really ned bindParam?

    - by sandelius
    Hi there! I'm trying to do a little PDO CRUD to learn some PDO. I have a question about bindParam. Here's my update method right now: public static function update($conditions = array(), $data = array(), $table = '') { self::instance(); // Late static bindings (PHP 5.3) $table = ($table === '') ? self::table() : $table; // Check which data array we want to use $values = (empty($data)) ? self::$_fields : $data; $sql = "UPDATE $table SET "; foreach ($values as $f => $v) { $sql .= "$f = ?, "; } // let's build the conditions self::build_conditions($conditions); // fix our WHERE, AND, OR, LIKE conditions $extra = self::$condition_string; // querystring $sql = rtrim($sql, ', ') . $extra; // let's merge the arrays into on $v_val = array_values($values); $c_val = array_values($conditions); $array = array_merge($v_val, self::$condition_array); $stmt = self::$db->prepare($sql); return $stmt->execute($array); } in my "self::$condition_array" I get all the right values from the ?. SO the query looks like this: UPDATE table SET this = ?, another = ? WHERE title = ? AND time = ? as you can see I dont use bindParams instead I pass the right values in the right order ($array) directly into the execute($array) method. This works like a charm BUT is it safe not use use bindParam here? If not then how can I do it? Thanks from Sweden Tobias

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  • How to check for a null object reference when validating forms in MVC

    - by quakkels
    Hello SO, I'm experimenting with validating forms in the asp.net MVC framework. I'm focusing on server side validation for the time being. I've come across an error that I'm not sure how to rectify. System.NullReferenceException: Object reference not set to an instance of an object. The code that throws the error is: [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create([Bind(Exclude="ID")] MembersCreate mc ) { mc.Modules = ModuleListDataContext.GetModuleList(); ViewData.Model = mc; //Validation using ModelState // // //line below errors when form field is empty // if ((string)mc.Member.Username.Trim() == "") ModelState.AddModelError("Member.Username", "Username is required."); if (!ModelState.IsValid) return View(); try { // TODO: Add insert logic here return RedirectToAction("Index","Home"); } catch { return View(); } } When I put spaces in the field it performs exactly as i want, but if I leave the field blank and press submit I get the error. What's the best way to avoid this error and still validate blank form fields? Thanks all -

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  • Need some help understanding this problem

    - by Legend
    I was wondering if someone could help me understand this problem. I prepared a small diagram because it is much easier to explain it visually. Problem I am trying to solve: 1. Constructing the dependency graph Given the connectivity of the graph and a metric that determines how well a node depends on the other, order the dependencies. For instance, I could put in a few rules saying that node 3 depends on node 4 node 2 depends on node 3 node 3 depends on node 5 But because the final rule is not "valuable" (again based on the same metric), I will not add the rule to my system. 2. Execute the request order Once I built a dependency graph, execute the list in an order that maximizes the final connectivity. First and foremost, I am wondering if I constructed the problem correctly and if I should be aware of any corner cases. Secondly, is there a closely related algorithm that I can look at? Currently, I am thinking of something like Feedback Arc Set or the Secretary Problem but I am a little confused at the moment. Any suggestions? PS: I am a little confused about the problem myself so please don't flame on me for that. If any clarifications are needed, I will try to update the question.

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  • SQL-Server: Is there an equivalent of a trigger for general stored procedure execution

    - by Arj
    Hi All, Hope you can help. Is there a way to reliably detect when a stored proc is being run on SQL Server without altering the SP itself? Here's the requirement. We need to track users running reports from our enterprise data warehouse as the core product we use doesn't allow for this. Both core product reports and a slew of in-house ones we've added all return their data from individual stored procs. We don't have a practical way of altering the parts of the product webpages where reports are called from. We also can't change the stored procs for the core product reports. (It would be trivial to add a logging line to the start/end of each of our inhouse ones). What I'm trying to find therefore, is whether there's a way in SQL Server (2005 / 2008) to execute a logging stored proc whenever any other stored procedure runs, without altering those stored procedures themselves. We have general control over the SQL Server instance itself as it's local, we just don't want to change the product stored procs themselves. Any one have any ideas? Is there a kind of "stored proc executing trigger"? Is there an event model for SQL Server that we can hook custom .Net code into? (Just to discount it from the start, we want to try and make a change to SQL Server rather than get into capturing the report being run from the products webpages etc) Thoughts appreciated Thanks

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  • How do I connect to SQL Server with VB?

    - by Wayne Werner
    Hi, I'm trying to connect to a SQL server from VB. The SQL server is across the network uses my windows login for authentication. I can access the server using the following python code: import odbc conn = odbc.odbc('SignInspection') c = conn.cursor() c.execute("SELECT * FROM list_domain") c.fetchone() This code works fine, returning the first result of the SELECT. However, I've been trying to use the SqlClient.SqlConnection in VB, and it fails to connect. I've tried several different connection strings but this is the current code: Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim conn As New SqlClient.SqlConnection conn.ConnectionString = "data source=signinspection;initial catalog=signinspection;integrated security=SSPI" Try conn.Open() MessageBox.Show("Sweet Success") 'Insert some code here, woo Catch ex As Exception MessageBox.Show("Failed to connect to data source.") MessageBox.Show(ex.ToString()) Finally conn.Close() End Try End Sub It fails miserably, and it gives me an error that says "A network-related or instance-specific error occurred... (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) I'm fairly certain it's my connection string, but nothing I've found has given me any solid examples (server=mySQLServer is not a solid example) of what I need to use. Thanks! -Wayne

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