Search Results

Search found 12376 results on 496 pages for 'side effects'.

Page 423/496 | < Previous Page | 419 420 421 422 423 424 425 426 427 428 429 430  | Next Page >

  • Semantically linking to code snippets

    - by Tim
    What's the most simple and semantic way of presenting code snippets in HTML? Possible XHTML syntax <a href="code_sample.php" type="text/x-php"> Example of widget creation </a> Example of linked file (code_sample.php): // Create a new widget $widget = new widget(); Pros: Semantically uses title to describe the source code being referenced Up to the client to render snippet Having very many custom server-side implementations tells me it should be standardized Browsers can have plug-ins for copy+paste, download, etc Seems to me this is where it belongs (not in Javascript) Degradation: non-compliant browsers receive a link to the associated content Cons: Not semantic enough? Seems wrong to replace hyperlinks with source code for presentation <object> might be better, but wouldn't degrade as nicely. Background I'm trying to create a "personal" XHTML standard for storing notes (wow, this is probably among the nerdiest things I've said). Since notes are just "scratch" it needs to be very lightweight. SO's markdown is very lightweight but not semantic enough for my needs. Plus, now I'm just curious. What's the most ideal syntax for linking to client-rendered code-snippets?

    Read the article

  • Object-oriented GUI development in python

    - by ptabatt
    Hey guys, new programmer here. I have an assignment for class and I'm stuck... What I need to do is a create a GUI that gives someone a basic arithmetic problem in one box, asks the person to answer it, evaluates it, and tells you if you're right or wrong... Basically, what I have is this: [code] class Lesson(Frame): def init (self, parent=None): Frame.init(self, parent) self.pack() Lesson.make_widgets(self) def make_widgets(self): Label(self, text="").pack(side=TOP) ent = Entry(self) self.a = randrange(1,10) self.b = randrange(1,10) self.expr = choice(["+","-"]) ent.insert(END, str(self.a) + str(self.expr) + str(self.a)) [/code] I've broken this down into many little steps and basically, what I'm trying to do right now is insert a default random expression into the first entry widget. When I run this code, I just get a blank Label. Why is that? How can I put a something like "7+7" into the box? If you absolutely need background to the problem, it's question #3 on this link. http://reed.cs.depaul.edu/lperkovic/csc242/homeworks/Homework8.html -Thanks for all help in advance.

    Read the article

  • What's a good Java-based Master-Slave communication mechanism?

    - by plecong
    I'm creating a Java application that requires master-slave communication between JVMs, possibly residing on the same physical machine. There will be a "master" server running inside a JEE application server (i.e. JBoss) that will have "slave" clients connect to it and dynamically register itself for communication (that is the master will not know the IP addresses/ports of the slaves so cannot be configured in advance). The master server acts as a controller that will dole work out to the slaves and the slaves will periodically respond with notifications, so there would be bi-directional communication. I was originally thinking of RPC-based systems where each side would be a server, but it could get complicated, so I'd prefer a mechanism where there's an open socket and they talk back and forth. I'm looking for a communication mechanism that would be low-latency where the messages would be mostly primitive types, so no serious serialization is necessary. Here's what I've looked at: RMI JMS: Built-in to Java, the "slave" clients would connect to the existing ConnectionFactory in the application server. JAX-WS/RS: Both master and slave would be servers exposing an RPC interface for bi-directional communication. JGroups/Hazelcast: Use shared distributed data structures to facilitate communication. Memcached/MongoDB: Use these as "queues" to facilitate communication, though the clients would have to poll so there would be some latency. Thrift: This does seem to keep a persistent connection, but not sure how to integrate/embed a Thrift server into JBoss WebSocket/Raw Socket: This would work, but require a lot more custom code than I'd like. Is there any technology I'm missing? Edit: Also looked at: JMX: Have the client connect to JBoss' JMX server and receive JMX notifications for bidirectional comms.

    Read the article

  • Any danger in calling flash messages html_safe?

    - by PreciousBodilyFluids
    I want a flash message that looks something like: "That confirmation link is invalid or expired. Click here to have a new one generated." Where "click here" is of course a link to another action in the app where a new confirmation link can be generated. Two drawbacks: One, since link_to isn't defined in the controller where the flash message is being set, I have to put the link html in myself. No big deal, but kind of messy. Number two: In order for the link to actually display properly on the page I have to html_safe the flash display function in the view, so now it looks like (using Haml): - flash.each do |name, message| = content_tag :div, message.html_safe This gives me pause. Everything else I html_safe has been HTML I've written myself in helpers and whatnot, but the contents of the flash hash are stored in a cookie client-side, and could conceivably be changed. I've thought through it, and I don't see how this could result in an XSS attack, but XSS isn't something I have a great understanding of anyway. So, two questions: 1. Is there any danger in always html_safe-ing all flash contents like this? 2. The fact that this solution is so messy (breaking MVC by using HTML in the controller, always html_safe-ing all flash contents) make me think I'm going about this wrong. Is there a more elegant, Rails-ish way to do this? I'm using Rails 3.0.0.beta3.

    Read the article

  • Page content layout issues

    - by Prupel
    I'm designing a theme for a blog and I'm having some trouble trying to get a layout working. Here's an image of what I want. This diagram represents the individual posts and not the website itself, so it will be contained in a box of it's own, lets call it .container. Also the purple and green are in another box, let's call it .content. The other elements will be called by their color for now. so here's more or less what the CSS looks like: .container { display:block; margin:0 25px; } .gray, .blue, .content { display:block; width:100%; } .purple { display:inline-block; width:125px; height:100%; text-align:center; } .green { display:inline-block; } That's all there is at the moment. I tried float but that made no effect. What's happening is something like this. Here's a few more things you should know: .container's width is NOT set it is auto .purple and .green don't necessarily need to be the same size as long as .green doesn't go to that side. .purple CAN have a set height .green is where the meat is, that's where the actual post goes, keep that in mind. I don't think tables will help, the problem is inside .content.

    Read the article

  • Problem with jquery #find on partial postback

    - by anonymous
    I have a third party component. It is a calendar control. I have a clientside event on it which fires javascript to show a popup menu. I do everything client side so I can use MVC. dd function MouseDown(oDayView, oEvent, element) { try { e = oEvent.event; var rightClick = (e.button == 2); if (rightClick) { var menu = $find("2_menuSharedCalPopUp"); menu.showAt(200, 200, e); } } catch (err) { alert("MouseDown() err: " + err.description); } } The javascript fires perfectly withe $find intially. I have another clientside method which updates the calendar via a partial postback. Once I have done this all subsequent MouseDowns( rightclicks) which use the $find statment error with 'null'. All similar problems people have out there seem to be around calling javascript after a postback - with solutions being re-registering an event using PageRequestManager or registering a clientside function on the server - et cetera. However, the event is firing, and the javascript working - it's the reference in the DOM that seems an issue. Any ideas?

    Read the article

  • how to update div tag in javascript with data from model for onsubmit form asp.net mvc

    - by michael
    In my page i have a form tag which submits to server ,gets data and redirects to same page. problem is the the div tag which has the data from server is not getting updated. how to do that in javascript <% using (Html.BeginForm("Addfile", "uploadfile", FormMethod.Post, new { id = "uploadform", enctype = "multipart/form-data" })) { %> <input type="file" id="addedFile" name="addedFile" /><br /> <input type="submit" id="addfile" value="Addfile" /> <div id="MyGrid"> //data from the model(server side) filelist is not updating</div> what will be the form onsubmit javascript function to update the div tag with the data from the model. and my uploadfile controller get post methods are as [AcceptVerbs(HttpVerbs.Get)] public ActionResult Upload() { return View(); } [AcceptVerbs(HttpVerbs.Post)] public ActionResult AddFile(HttpPostedFileBase addedFile) { static List<string> fileList = new List<string>(); string filename = Path.GetFileName(addedFile.FileName); file.SaveAs(@"D:\Upload\" + filename); fileList.Add(filename); return("Upload",fileList); } thanks, michaela

    Read the article

  • The OpenID Provider issued an assertion for an Identifier whose discovery information did not match

    - by Sohail
    I used sample code from DotNetOpenAuth.net to become my own OpenID Provider (OpenIDProviderWebForm) everything worked fine and I was able to test my OP against NerdDinner. now I want to customize the identifier like --- http://www.mydomain.com/user.aspx/Hash(Username+PrivateKey)~Username. everything works on OP side but on the NerdDinner application when the app tries to do HttpRequestInfo clientResponseInfo = new HttpRequestInfo("GET", auth, auth.PathAndQuery, headers, null); response = RelyingParty.GetResponse(clientResponseInfo); (you find these two lines of codes in AuthController.cs from NerdDinner) the response contains below error: The OpenID Provider issued an assertion for an Identifier whose discovery information did not match. Assertion endpoint info: ClaimedIdentifier: http://localhost:57571/user.aspx/76208371132EC7F7A37472C8B4CC2CC37A05B707~sohail ProviderLocalIdentifier: http://localhost:57571/user.aspx/76208371132EC7F7A37472C8B4CC2CC37A05B707~sohail ProviderEndpoint: http://localhost:57571/server.aspx OpenID version: 2.0 Service Type URIs: Discovered endpoint info: [ { ClaimedIdentifier: http://localhost:57571/user.aspx/EA467E35736AC22EB60C04C2E9D9594263B60ECB~sohail ProviderLocalIdentifier: http://localhost:57571/user.aspx/EA467E35736AC22EB60C04C2E9D9594263B60ECB~sohail ProviderEndpoint: http://localhost:57571/server.aspx OpenID version: 2.0 Service Type URIs: http://specs.openid.net/auth/2.0/signon http://openid.net/extensions/sreg/1.1 }, { ClaimedIdentifier: http://localhost:57571/user.aspx/EA467E35736AC22EB60C04C2E9D9594263B60ECB~sohail ProviderLocalIdentifier: http://localhost:57571/user.aspx/EA467E35736AC22EB60C04C2E9D9594263B60ECB~sohail ProviderEndpoint: http://localhost:57571/server.aspx OpenID version: 1.0 Service Type URIs: http://openid.net/signon/1.0 http://openid.net/extensions/sreg/1.1 }, ] anybody can help me please?

    Read the article

  • SQL Server Collation / ADO.NET DataTable.Locale with different languages

    - by Turro
    Hi all, we have WinForms app which stores data in SQL Server (2000, we are working on porting it in 2008) through ADO.NET (1.1, working on porting to 4.0). Everything works fine if I read data previsouly written in Western-European locale (E.g.: "test", "test ù"), but now we have to be able to mix Western and non-Western alphabets as well (E.g.: "test - ???" - these are just random arabic chars). On the SQL Server side, database has been set with the Latin1_General collation, the field is a nvarchar(80). If I run a SQL SELECT statement (E.g.: "SELECT * FROM MyTable WHERE field = 'test - ???'", don't mind about the "*" or the actual names) from Query Analyzer, I get no results; the same happens if I pass the Sql statement to an ADO.NET DataAdapter to fill a DataTable. My guess is that it has something to do with collation, but I don't know how to correct this: do I have to change to collation (SQL Server) to a different one? Or do I have to set the locale on the DataAdaoter/DataTable (ADO.NET)? Thanks in advance to anyone who will help

    Read the article

  • Return value from Object match

    - by Hito_kun
    I'm, by no means, JS fluent, so forgive me if im asking for some really basic stuff, but I've not being able to find a proper answer to my question. Im writting my first Node.js (plus Extra Framework and Socket.io) app and Im having some fun setting up the server side of a FB-like messenger (surprise!!!). So, let's say I have this data structure to store online users(This is a JSON Array, but I'm not sure it is the best way to do it or should I go with Javascript Objects): [ { "site": 45, "users": [ { "idUser": 5, "idSocket": "qwe87r7w8qwe", "name": "Carlos Ray Norris" }, { "idUser": 6, "idSocket": "v8d9d0fgfs7d", "name": "John Connor" } ] }, { "site": 48, "users": [ { "idUser": 22, "idSocket": "qwe87r7w8qwe", "name": "David Bowie" }, { "idUser": 23, "idSocket": "v8d9d0fgfs7d", "name": "Barack H. Obama" } ] } ] What I want to do is to search in the array for x value given y. In this case, retrieving the idSocket knowing the idUser WITHOUT having to run through the array values. So I have basically 2 questions: first, what would be the proper way to store users online? and secondly, how to find values matching with the values I already know (find the idSocket that has a given idUser). I would like a pure JS approach(or using some of the tools given by Node, Socket.io or Express), but if that's not possible then I can look for some JQuery.

    Read the article

  • Is there a tool for managing redundant pages across a website?

    - by dmanexe
    I am in charge of constructing a website with a '2-dimensional' site map, as explained later. I am looking for (preferably a Wordpress plugin, as the site is built in Wordpress already) that would make managing thousands of pages a lot easier. To explain further, let me iterate my situation. I am building a website for a construction company, and they have several key cities and several key services. Now, they want a parent page for each service, and another unique page for the child sub-service, and finaly, a grandchild page for the city they are performing the service in. For example, if they were doing Concrete Construction in Los Angeles, the URL would look like: /concrete/construction/los-angeles The content on /los-angeles would be the same as on /malibu, or /burbank. However, there would be a different set of content for /concrete/design/los-angeles, but the entire page content (sans a few variables with city names) would be the same. Is there a way to manage or automate 'matrixing' this information on the site? I am looking for a tool that would allow me to easily add a 'city' with the same content across all grandchildren, per the child's content requirements. All of the grandchildren pages will have redundant content across them. Should something like this not exist, how difficult would it be to create, as a freelance side project? I need a tool like this, because I am approaching about ~500 cities and 50 services (Concrete Construction, Concrete Design, Concrete Engineering, etc)

    Read the article

  • How to deal with clients and iterations in Agile team?

    - by Ondrej Slinták
    This thread is a follow up to my previous one. It's in fact 2 questions, so I hope no one minds, as they are dependent on each other. We are starting a new project at work and we consider it as a great opportunity to try Agile techniques in action. We had a brainstorming about ideas we read in several books and articles, and came up with concept that would suit us the best: 2 weeks iteration, followed by call with clients who would choose what stuff they want to have in next iteration. I just have few more questions, which we couldn't figure out ourselves. What to do in the first iteration? What to, generally, do in the first few iterations if we start from the scratch? Just give it a month of development to code core of the application or start with simple wire-frames with limited pre-coded functionality? What usually clients want to see? Shiny stuff that doesn't work or ugly stuff that does work? How to communicate with clients? Our initial thought it to set the process to something like this: Is it a good idea to have a Focal Point on client side or is it better to communicate straight with all the clients to prevent miscommunication? Any thoughts are welcome! Thanks in advance.

    Read the article

  • How do i write tasks? (parallel code)

    - by acidzombie24
    I am impressed with intel thread building blocks. I like how i should write task and not thread code and i like how it works under the hood with my limited understanding (task are in a pool, there wont be 100 threads on 4cores, a task is not guaranteed to run because it isnt on its own thread and may be far into the pool. But it may be run with another related task so you cant do bad things like typical thread unsafe code). I wanted to know more about writing task. I like the 'Task-based Multithreading - How to Program for 100 cores' video here http://www.gdcvault.com/sponsor.php?sponsor_id=1 (currently second last link. WARNING it isnt 'great'). My fav part was 'solving the maze is better done in parallel' which is around the 48min mark (you can click the link on the left side. That part is really all you need to watch if any). However i like to see more code examples and some API of how to write task. Does anyone have a good resource? I have no idea how a class or pieces of code may look after pushing it onto a pool or how weird code may look when you need to make a copy of everything and how much of everything is pushed onto a pool.

    Read the article

  • Setting up a domain using WAMP and NameCheap's DNS service

    - by Mike Jones
    So, I've been working on this for far longer than I should be and I'm quite thoroughly perplexed and lost. I apologize if this turns out to be a facile question, but I'm entirely befuddled and very much in need of some guidance. Earlier today I registered a cheap .info domain on NameCheap just to play around with as I learn webdev. I have WAMP installed on my computer and I've been testing my projects through localhost. I thought it would be a good idea to have a domain at my disposal in order to understand how it works and better test my work. NameCheap has a complimentary DNS service (not that I entirely understand what DNS is, although I tried), so I'm using that. I direct both the "@" and "www" host names to my IP address, as shown in the below tutorial: https://www.namecheap.com/support/knowledgebase/article.aspx/319/78/how-can-i-setup-an-a-address-record-for-my-domain However, now when I go to the URL of the domain I bought, it confronts me with a login box that seems to be coming from my wifi network. How do I set this up so that it hosts the information in my WAMP server? Thanks in advance for any help, I really appreciate it. And, as a side-note, what should read (print or online) to better understand the structure of the internet? I've been studying HTML/CSS/Javascript, but I'm not sure where to look for pragmatic and comprehensive information on how the internet works and how to utilize it as a website administrator. Thanks so much.

    Read the article

  • Why doesn't this data binding work?

    - by Qwertie
    I have a ViewModel class that contains a list of points, and I am trying to bind it to a Polyline. The Polyline picks up the initial list of points, but does not notice when additional points are added even though I implement INotifyPropertyChanged. What's wrong? <StackPanel> <Button Click="Button_Click">Add!</Button> <Polyline x:Name="_line" Points="{Binding Pts}" Stroke="Black" StrokeThickness="5"/> </StackPanel> C# side: // code-behind _line.DataContext = new ViewModel(); private void Button_Click(object sender, RoutedEventArgs e) { // The problem is here: NOTHING HAPPENS ON-SCREEN! ((ViewModel)_line.DataContext).AddPoint(); } // ViewModel class public class ViewModel : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; public PointCollection Pts { get; set; } public ViewModel() { Pts = new PointCollection(); Pts.Add(new Point(1, 1)); Pts.Add(new Point(11, 11)); } public void AddPoint() { Pts.Add(new Point(25, 13)); if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Pts")); } }

    Read the article

  • Raising events and object persistence in Django

    - by Mridang Agarwalla
    Hi, I have a tricky Django problem which didn't occur to me when I was developing it. My Django application allows a user to sign up and store his login credentials for a sites. The Django application basically allows the user to search this other site (by scraping content off it) and returns the result to the user. For each query, it does a couple of queries of the other site. This seemed to work fine but sometimes, the other site slaps me with a CAPTCHA. I've written the code to get the CAPTCHA image and I need to return this to the user so he can type it in but I don't know how. My search request (the query, the username and the password) in my Django application gets passed to a view which in turn calls the backend that does the scraping/search. When a CAPTCHA is detected, I'd like to raise a client side event or something on those lines and display the CAPTCHA to the user and wait for the user's input so that I can resume my search. I would somehow need to persist my backend object between calls. I've tried pickling it but it doesn't work because I get the Can't pickle 'lock' object error. I don't know to implement this though. Any help/ideas? Thanks a ton.

    Read the article

  • two controllers in one layout, rails 3

    - by Grizlord
    Okay, I have two models, a recipe model and a category model. In my layout(application.html.erb) I have a main container div that "yields" the recipes index action. I'm trying to list all the category names as links in a side bar(also a div) by iterating over them in an unordered list. When you click one of the links it will go to the category show page which will then list all the recipes in that category. Here is how I'm trying to list the links in - <div class="container" id="categories"> <% for category in @categories %> <ul> <li><%= link_to category.name, category %></li> </ul> <% end %> </div> The problem is I get a NoMethodError - You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each It is not retrieving the records from the model. Any suggestions on how to get this done would be greatly appreciated. I tried to render a partial as some of the other similar posts have said but still get the same error. This is the exact error - NoMethodError in Recipes#index Showing /Users/grizlord/Rails/recipe2/app/views/layouts/application.html.erb where line #39 raised: You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each Extracted source (around line #39): 36: </div> 37: <div class="container" id="categories"> 38: Browse by Category 39: <% for category in @categories %> 40: <ul> 41: <li><%= link_to category.name, category %></li> 42: </ul>

    Read the article

  • Twitter API Rate Limit - Overcoming on an unauthenticated JSON Get with Objective C?

    - by Cian
    I see the rate limit is 150/hr per IP. This'd be fine, but my application is on a mobile phone network (with shared IP addresses). I'd like to query twitter trends, e.g. GET /trends/1/json. This doesn't require authorization, however what if the user first authorized with my application using OAuth, then hit the JSON API? The request is built as follows: - (void) queryTrends:(NSString *) WOEID { NSString *urlString = [NSString stringWithFormat:@"http://api.twitter.com/1/trends/%@.json", WOEID]; NSURL *url = [NSURL URLWithString:urlString]; NSURLRequest *theRequest=[NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10.0]; NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self startImmediately:YES]; if (theConnection) { // Create the NSMutableData to hold the received data. theData = [[NSMutableData data] retain]; } else { NSLog(@"Connection failed in Query Trends"); } //NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]]; } I have no idea how I'd build this request as an authenticated one however, and haven't seen any examples to this effect online. I've read through the twitter OAuth documentation, but I'm still puzzled as to how it should work. I've experimented with OAuth using Ben Gottlieb's prebuild library, and calling this in my first viewDidLoad: OAuthViewController *oAuthVC = [[OAuthViewController alloc] initWithNibName:@"OAuthTwitterDemoViewController" bundle:[NSBundle mainBundle]]; // [self setViewController:aViewController]; [[self navigationController] pushViewController:oAuthVC animated:YES]; This should store all the keys required in the app's preferences, I just need to know how to build the GET request after authorizing! Maybe this just isn't possible? Maybe I'll have to proxy the requests through a server side application? Any insight would be appreciated!

    Read the article

  • Service Bus / Request Forwarding

    - by codputer
    I'm doing some development with a thrid party that issues either a Get or POST to a public URL that I specify. What I would like to do is set up a Relay service on the Azure Service Bus that my dev machine can listen to. When the request comes in, I want to forward that request as if my web service was taking the request directly from the thrid party service. When I'm ready, I'll deploy the application to a public service, change the URL that the thrid party service is sending too, and viola I should be up and running. What I'm looking for looks exactly like this: Clemens the Master of Service Bus but it's from the 2009 CTP. I'm working at it, but haven't yet got it working using all the new bits in 2012 (a.ka. its over my head at the moment). Somebody want to help? Clemens also help somebody else create a Reverse Proxy using the Service Bus, but I can't seem to find it. Yes I've also tweeted Clemens, but I'm sure he is a busy man! p.s. I know about Application Request Routing, but my dev machine is not on a public URL, I need to rewrite the URL after my client listener on the service bus recieves the message that was relayed from the Server side endpoint.

    Read the article

  • MySQL bindings for Rails 2.3.5 on Mac OS X 10.5.8

    - by lach
    I have a rails environment which I set-up with macports. I recently updated macports which seems to have had the side effect of breaking rails. When I try to boot a rails server I get: $ ./script/server => Booting WEBrick => Rails 2.3.5 application starting on http://0.0.0.0:3000 /opt/local/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/gem_dependency.rb:119:Warning: Gem::Dependency#version_requirements is deprecated and will be removed on or after August 2010. Use #requirement !!! The bundled mysql.rb driver has been removed from Rails 2.2. Please install the mysql gem and try again: gem install mysql. /opt/local/lib/ruby/vendor_ruby/1.8/i686-darwin9/mysql.bundle: dlopen(/opt/local/lib/ruby/vendor_ruby/1.8/i686-darwin9/mysql.bundle, 9): Library not loaded: /opt/local/lib/mysql5/mysql/libmysqlclient.15.dylib (LoadError) Referenced from: /opt/local/lib/ruby/vendor_ruby/1.8/i686-darwin9/mysql.bundle Reason: image not found - /opt/local/lib/ruby/vendor_ruby/1.8/i686-darwin9/mysql.bundle I've tried reinstalling the mysql gem many times using various configurations I've found around the web but nothing seems to help. Also, when I try to use rake I get: rake db:migrate Rails requires RubyGems >= 1.3.1 (you have 1.0.1). Pleasegem update --systemand try again. Even though: gem --version 1.3.6 What's going on here?

    Read the article

  • NSURLConnection receives data even if no data was thrown back

    - by Anna Fortuna
    Let me explain my situation. Currently, I am experimenting long-polling using NSURLConnection. I found this and I decided to try it. What I do is send a request to the server with a timeout interval of 300 secs. (or 5 mins.) Here is a code snippet: NSURL *url = [NSURL URLWithString:urlString]; NSURLRequest *request = [NSURLRequest requestWithURL:url cachePolicy:NSURLCacheStorageAllowedInMemoryOnly timeoutInterval:300]; NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&resp error:&err]; Now I want to test if the connection will "hold" the request if no data was thrown back from the server, so what I did was this: if (data != nil) [self performSelectorOnMainThread:@selector(dataReceived:) withObject:data waitUntilDone:YES]; And the function dataReceived: looks like this: - (void)dataReceived:(NSData *)data { NSLog(@"DATA RECEIVED!"); NSString *string = [NSString stringWithUTF8String:[data bytes]]; NSLog(@"THE DATA: %@", string); } Server-side, I created a function that will return a data once it fits the arguments and returns none if nothing fits. Here is a snippet of the PHP function: function retrieveMessages($vardata) { if (!empty($vardata)) { $result = check_data($vardata) //check_data is the function which returns 1 if $vardata //fits the arguments, and 0 if it fails to fit if ($result == 1) { $jsonArray = array('Data' => $vardata); echo json_encode($jsonArray); } } } As you can see, the function will only return data if the $result is equal to 1. However, even if the function returns nothing, NSURLConnection will still perform the function dataReceived: meaning the NSURLConnection still receives data, albeit an empty one. So can anyone help me here? How will I perform long-polling using NSURLConnection? Basically, I want to maintain the connection as long as no data is returned. So how will I do it? NOTE: I am new to PHP, so if my code is wrong, please point it out so I can correct it.

    Read the article

  • In Javascript, is it true that function aliasing works as long as the function being aliased doesn't

    - by Jian Lin
    In Javascript, if we are aliasing a function, such as in: f = g; f = obj.display; obj.f = foo; all the 3 lines above, they will work as long as the function / method on the right hand side doesn't touch this? Since we are passing in all the arguments, the only way it can mess up is when the function / method on the right uses this? Actually, line 1 is probably ok if g is also a property of window? If g is referencing obj.display, then the same problem is there. In line 2, when obj.display touches this, it is to mean the obj, but when f() is invoked, the this is window, so they are different. In line 3, it is the same: when f() is invoked inside of obj's code, then the this is obj, while foo might be using this to refer to window if it were a property of window. (global function). So line 2 can be written as f = function() { obj.display.apply(obj, arguments) } and line 3: obj.f = function() { foo.apply(window, arguments) } Is this the correct method, and are there there other methods besides this?

    Read the article

  • Dynamically add items to Tkinter Canvas

    - by nick369
    I'm attempting to learn Tkinter with the goal of being able to create a 'real-time' scope to plot data. As a test, I'm trying to draw a polygon on the canvas every time the 'draw' button is pressed. The triangle position is randomized. I have two problems: There is a triangle on the canvas as soon as the program starts, why and how do I fix this? It doesn't draw any triangles when I press the button, at least none that I can see. CODE from Tkinter import * from random import randint class App: def __init__(self,master): #frame = Frame(master) #frame.pack(side = LEFT) self.plotspc = Canvas(master,height = 100, width = 200, bg = "white") self.plotspc.grid(row=0,column = 2, rowspan = 5) self.button = Button(master, text = "Quit", fg = "red", \ command = master.quit) self.button.grid(row=0,column=0) self.drawbutton = Button(master, text = "Draw", command = \ self.pt([50,50])) self.drawbutton.grid(row = 0, column = 1) def pt(self, coords): coords[0] = coords[0] + randint(-20,20) coords[1] = coords[1] + randint(-20,20) x = (0,5,10) y = (0,10,0) xp = [coords[0] + xv for xv in x] yp = [coords[1] + yv for yv in y] ptf = zip(xp,yp) self.plotspc.create_polygon(*ptf) if _name_ == "_main_": root = Tk() app = App(root) root.mainloop() The code is formatting strangely within the code tags, I have no idea how to fix this.

    Read the article

  • CORBA on MacOS X (Cocoa)

    - by user8472
    I am currently looking into different ways to support distributed model objects (i.e., a computational model that runs on several different computers) in a project that initially focuses on MacOS X (using Cocoa). As far as I know there is the possibility to use the class cluster around NSProxy. But there also seem to be implementations of CORBA around with Objective-C support. At a later time there may be the need to also support/include Windows machines. In that case I would need to use something like Gnustep on the Windows side (which may be an option, if it works well) or come up with a combination of both technologies. Or write something manually (which is, of course, the least desirable option). My questions are: If you have experience with both technologies (Cocoa native infrastructure vs. CORBA) can you point out some key features/issues of either approach? Is it possible to use Gnustep with Cocoa in the way explained above? Is it possible (and reasonably feasible, i.e. simpler than writing a network layer manually) to communicate among all MacOS clients using Cocoa's technology and with Windows clients through CORBA?

    Read the article

  • .Net lambda expression-- where did this parameter come from?

    - by larryq
    I'm a lambda newbie, so if I'm missing vital information in my description please tell me. I'll keep the example as simple as possible. I'm going over someone else's code and they have one class inheriting from another. Here's the derived class first, along with the lambda expression I'm having trouble understanding: class SampleViewModel : ViewModelBase { private ICustomerStorage storage = ModelFactory<ICustomerStorage>.Create(); public ICustomer CurrentCustomer { get { return (ICustomer)GetValue(CurrentCustomerProperty); } set { SetValue(CurrentCustomerProperty, value); } } private int quantitySaved; public int QuantitySaved { get { return quantitySaved; } set { if (quantitySaved != value) { quantitySaved = value; NotifyPropertyChanged(p => QuantitySaved); //where does 'p' come from? } } } public static readonly DependencyProperty CurrentCustomerProperty; static SampleViewModel() { CurrentCustomerProperty = DependencyProperty.Register("CurrentCustomer", typeof(ICustomer), typeof(SampleViewModel), new UIPropertyMetadata(ModelFactory<ICustomer>.Create())); } //more method definitions follow.. Note the call to NotifyPropertyChanged(p => QuantitySaved) bit above. I don't understand where the "p" is coming from. Here's the base class: public abstract class ViewModelBase : DependencyObject, INotifyPropertyChanged, IXtremeMvvmViewModel { public event PropertyChangedEventHandler PropertyChanged; protected virtual void NotifyPropertyChanged<T>(Expression<Func<ViewModelBase, T>> property) { MvvmHelper.NotifyPropertyChanged(property, PropertyChanged); } } There's a lot in there that's not germane to the question I'm sure, but I wanted to err on the side of inclusiveness. The problem is, I don't understand where the 'p' parameter is coming from, and how the compiler knows to (evidently?) fill in a type value of ViewModelBase from thin air? For fun I changed the code from 'p' to 'this', since SampleViewModel inherits from ViewModelBase, but I was met with a series of compiler errors, the first one of which statedInvalid expression term '=>' This confused me a bit since I thought that would work. Can anyone explain what's happening here?

    Read the article

< Previous Page | 419 420 421 422 423 424 425 426 427 428 429 430  | Next Page >