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  • Prevent Erroneous Property Assignment

    - by Gordon
    Porting android applications to iphone applications always gives me the following pattern that I accidentally create: - (void) myFunc:(id)prop { self.property = property; } Which instead should be: - (void) myFunc:(id)prop { self.property = prop; } This always causes my program to quietly break because property gets reset to its existing value rather than being set to the new value, 'prop'. I cannot name the parameter 'prop' to 'property' since the compile complains that the parameter masks the instance variables visibility. Is there a good way to avoid this situation? There are no compiler warnings. Is there a way to make xcode prevent this? I cannot see very many situations where you would set a property to the value of its underlying instance variable (maybe to trigger a KVO binding?), but I don't see myself doing that in majority of cases. I understand the above code is synthetic and should be done with @synthesize, but I am just using it as a simplified example to illustrate my point.

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  • Exceptions confusion

    - by Misiur
    Hi there. I'm trying to build site using OOP in PHP. Everyone is talking about Singleton, hermetization, MVC, and using exceptions. So I've tried to do it like this: Class building whole site: class Core { public $is_core; public $theme; private $db; public $language; private $info; static private $instance; public function __construct($lang = 'eng', $theme = 'default') { if(!self::$instance) { try { $this->db = new sdb(DB_TYPE.':host='.DB_HOST.';dbname='.DB_NAME, DB_USER, DB_PASS); } catch(PDOException $e) { throw new CoreException($e->getMessage()); } try { $this->language = new Language($lang); } catch(LangException $e) { throw new CoreException($e->getMessage()); } try { $this->theme = new Theme($theme); } catch(ThemeException $e) { throw new CoreException($e->getMessage()); } } return self::$instance; } public function getSite($what) { return $this->language->getLang(); } private function __clone() { } } Class managing themes class Theme { private $theme; public function __construct($name = 'default') { if(!is_dir("themes/$name")) { throw new ThemeException("Unable to load theme $name"); } else { $this->theme = $name; } } public function getTheme() { return $this->theme; } public function display($part) { if(!is_file("themes/$this->theme/$part.php")) { throw new ThemeException("Unable to load theme part: themes/$this->theme/$part.php"); } else { return 'So far so good'; } } } And usage: error_reporting(E_ALL); require_once('config.php'); require_once('functions.php'); try { $core = new Core(); } catch(CoreException $e) { echo 'Core Exception: '.$e->getMessage(); } echo $core->theme->getTheme(); echo "<br />"; echo $core->language->getLang(); try { $core->theme->display('footer'); } catch(ThemeException $e) { echo $e->getMessage(); } I don't like those exception handlers - i don't want to catch them like some pokemons... I want to use things simple: $core-theme-display('footer'); And if something is wrong, and debug mode is enabled, then aplication show error. What should i do?

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  • Reference variable to an object instantiated/initialized in another class in Java

    - by Alex
    The reason I'm asking is because I'm getting NullPointerException. I now this is very easy but I'm pretty new programming and find this a bit confusing. So say I have initialized an object in a class and want to access that same object from another class. Like now for instance I'm working on a small Chess game, in my model Game class I have an instance of Board, an object. Board, in turn, has an array of Squares. Square[][]. Game has board, board has Square[][]. Now if I want to access the Square[][] through the object board (in Game) of type Board. Do I just declare a variable with the same name and type or do I have to initialize it again? Board board OR Board board = new Board(); Note, I have already initialized board in the class Game so if I do it again, won't they be two totally different Board objects?

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  • iPhone developing FOR jailbroken devices (not USING jailbroken devices!)

    - by Marek
    I would like to dig into developing for jailbroken devices, just to test what the device could do. I would like, for instance, to alter the ipod music based on geo-location, so i have to program a new daemon that runs in background and fetch gps informations at regular interlavs and then make something with them. Longitude, longitude, for instance, does exactly this, even when the device is locked, and then upload the informations on google latidude. I have some experience as an iphone developer, but i'm not sure on where to find documentation to accomplish such a task. I know about the books "iphone open application development" and "the iphone developer's coockbook", but i don't own them and i'm not sure they have what i'm looking for. Any advice on this?

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  • Type hinting and optional attributes in PHP

    - by Álvaro G. Vicario
    I have a class method that deals with dates: public function setAvailability(DateTime $start, DateTime $end){ } Since item availability can have lower limit, upper limit, both or none, I'd like to make setAvailability() accept NULL values as well. However, the NULL constant violates the type hinting: $foo->setAvailability(NULL, $end); triggers: Catchable fatal error: Argument 1 passed to Foo::setAvailability() must be an instance of DateTime, null given And, as far as I know, I cannot have a DateTime instance with no value. (Can I?) For a reason I cannot grasp, this seems to work: public function setAvailability(DateTime $start=NULL, DateTime $end=NULL){ } ... $foo->setAvailability(NULL, $end); But it looks like a hack that works by pure chance. How would you deal with unset dates in PHP classes?

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  • Globally overrride MonthNames for all instances of a specific culture

    - by Pauli Østerø
    So, i have this problem where Microsoft actually got the month names wrong for the Greenlandic culture (kl-GL). I also know that i can pass my own array of string to the DateTimeFormatInfo.MonthNames Property, but it seems like the values i specify is only used in the scope of that one CultureInfo instance. Is there a way to tell .Net that every time i have an instance of the kl-GL culture these specific monthnames should be used? I know that you can create user specific cultures, but i don't have access to some legacy code to actually change the code to use a my own userspecified culture.

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  • How to elegantly work with a lot of print functions?

    - by user1824372
    I'm working on a Python project that is executed on a terminal (or console) for which I am planning to implement a GUI. I did not major in CS so I really have no idea how to effectively design a terminal GUI such that: the user interface looks good in GUI, it is directed to a certain widget, let's say, a text label, or a bottom bar, or a hide-able frame. Do you have any suggestions? Currently, I am using the print function to provide essential information on STDOUT during execution, so a lot of print calls are distributed here and there in the code. I'm thinking of using macro-like variables such as 'FILE_NOT_EXISTS_MESSAGE' for printing, and all of them and their values would be defined in one file. Is that a standard way to do this? Should I introduce a logging system? In summary, I'm looking for a pattern for handling console output that is effective and adaptable.

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  • C# Why does this code not show a GUI properly?

    - by Tom
    class Program { static String ChannelName = null; static Form1 f; static void Main() { f = new Form1(); f.Show(); try { MY CODE WHICH CALLS INTO ANOTHER CLASS BUT CANNOT PASS THE GUI INSTANCE AS IT USES REMOTING } } } I know this isnt the best/normal way to do it, but i need to write data to the GUI from a class which has bo instance of the GUI so i was going to call Program.method() and use a function to write to the GUI in program. However when i run the above my GUI displays but with the windows hourglass? Could someone show me a quick fix so that i can still crudely show the GUI, let the application code run and then later write to the GUI?

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  • Good places for starting to learn Lua scripting [closed]

    - by Cascalho
    I want to start learning to script in lua for game development. I could start with the official Lua tutorials, but I would rather study scripts that were written specifically for games and learn the syntax from there as I believe this is faster and more related to what I want. Can you recommend tutorials in video or text that are very detailed in explaining the code? Or some open source game with heavily commented code? What I want is something detailed that walks me through it, so I start understanding both the syntax and how each piece relate to each other, like "First of all, install this, this and that." "So, here we are defining a new function that will make the player jump." "This is the main script that calls the other ones. It defines these variables." "This function tests if the player is alive."

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  • Does every browser open a new HTTPSession

    - by user496934
    I am working on a webbased application which has JSP and servlets. In my application, I am binding some objects to sessions like the following code -- HttpSession session = p_req.getSession(); session.setAttribute(DOWNLOAD_With_WARNINGS, downloadMap); Later I am retrieving them using session.getAttribute. I would like to know if every time I open a new browser does it open a new HTTP session. Because , if I do a setAttribute with some value in one browser instance, that change is visible when I do a getAttribute using the other browser instance.

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  • What is the best way to INSERT a large dataset into a MySQL database (or any database in general)

    - by Joe
    As part of a PHP project, I have to insert a row into a MySQL database. I'm obviously used to doing this, but this required inserting into 90 columns in one query. The resulting query looks horrible and monolithic (especially inserting my PHP variables as the values): INSERT INTO mytable (column1, colum2, ..., column90) VALUES ('value1', 'value2', ..., 'value90') and I'm concerned that I'm not going about this in the right way. It also took me a long (boring) time just to type everything in and testing writing the test code will be equally tedious I fear. How do professionals go about quickly writing and testing these queries? Is there a way I can speed up the process?

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  • sql server 2008 express. cannot create mdf databse.

    - by yair
    Hi, I'm working with visual studio 2008 express and sql 2008 express. I'm trying to create mdf database (Add new Item ...)and I recieve the following error message: "a network-related or instance-specific error occured while establishing a connection to SQL Server. The server was not found or was not accessible. Verfy that instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named pipes Provider:40 - could not open connection to SQL)" Why ? Is it possible to create mdf database with SQL 2008 Express ? If it is then what to do ?

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  • Save or update for FK relationship Sqlalchemy

    - by Alex
    I've googled, but haven't been able to find the answer to this seemingly simple question. I have two relations, a customer and an order. Each order is associated to a single cusomter, and therefore has a FK relationship to the customer table. The customer relation only stores customer names, and I have set a unique constraint on the customer table barring duplicate names. Let's say I create a new order instance and set a customer for the order. Something like: order_instance.customer = Customer("customer name") When I save the order instance, SqlAlchemy will complain if a customer with this name already exists in the customer table. How do I specify to SqlAlchemy to insert into the customer table if a customer with this name doesn't already exist, or just ignore (or even update) to the customer relation? I don't really want to have to check each time if a customer with some name already exists...

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  • waitin closes browsers for all projects that are building.

    - by Scooter
    I'm having an issue running WatiN under CruiseControl.net, where on a .forceclose, watin is closing all open browser instances. I have multiple projects running under cruisecontrol, and its not uncommon for some of those projects to be building and testing at the same time. There has been more than one occasion where watin will close the browser window for a different project, causing it to fail. In my local tests, creating my watin instance under a new process fixes this issue. But running under cruisecontrol, when doing this, I lose my IE object: Object reference not set to an instance of an object. Running CC.net as a service CC.Net server is Windows 2003 IE6 Any thoughts?

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  • possible to show composition relationship in a diagram generated from PHP source code?

    - by ajsie
    i have tested several UML applications for whether they could show composition relationships in the UML diagrams generated form the PHP source code or not, and the result is they can't. i know that this is a typical problem for PHP cause we don't declare a data type when we code, so it's difficult for the UML applications to know if an instance variable is a reference to an object or not. i also tested nWire with the same result. will there never be applications that could show us a complete map over all object relationships more than just inheritance? i think it's a pity that you can't have a good view over all the relationships for an application. cause when i use an open source solution, i always want to know how the objects are related to each other. maybe we could make comments for the instance variable telling the software that this is an reference to an object? but that would mean that the mapping software is using this solution. i feel its a pity nWire/visual paradigm can't give us a complete map:(

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  • NSTableview objectAtIndex error

    - by Matt S.
    I followed the guide here, but for some reason, the table view shows this in the console when I attempt to scroll through it: -[NSCFString objectAtIndex:]: unrecognized selector sent to instance 0x100227710

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  • How to make Amazon EC2 not cause SSL invalid error in browser

    - by tadatoshi
    I use SSL certificate for a web site I set up in Amazon EC2 Machine Instance. The SSL certificate is for one domain name, which is not public DNS for the Amazon Machine Instance. The browser always complains the mismatch in the domain name because it compares the domain name of the SSL certificate to the Amazon public DNS. How can I set up not to cause this problem? I tried both domain name forwarding and A Record setting. Maybe it's because I'm not so familiar with Amazon EC2 and I haven't configured domain name correctly. Any help will be greatly appreciated.

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  • Will I use HtmlDocument even I want to parse the HTML string using HtmlAglityPack ?

    - by skhan
    Hi everyone, I'm working in C#. I'm trying to extract the first instance of img tag from a HTML string (which is actually a post data). This is my code: private string GrabImage(string htmlContent) { String firstImage; HtmlAgilityPack.HtmlDocument htmlDoc = new HtmlAgilityPack.HtmlDocument(); htmlDoc.LoadHtml(htmlContent); HtmlAgilityPack.HtmlNode imageNode = htmlDoc.DocumentNode.SelectSingleNode("//img"); if (imageNode != null) { return firstImage = imageNode.ToString(); } else return firstImage=" "; } But it gets null in htmlDoc, will I use the HtmlDocument type even if I'm trying to parse the HTML from a string ? P.S btw is it the correct way of grabbing the first instance of image tag from my HTML string?

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  • Running script constantly in background: daemon, lock file with crontab, or simply loop?

    - by Mauritz Hansen
    I have a Perl script that queries a database for a list of files to process processes the files and then exits Upon startup this script creates a file (let's say script.lock), and upon exit it removes this file. I have a crontab entry that runs this script every minute. If the lockfile exists then the script exits, assuming that another instance of itself is running. The above process works fine but I am not very happy with the robustness of this approach. Specifically, if for some reason the script exits prematurely and the lockfile is not removed then a new instance will not execute properly. I would appreciate some advice on the following: Is using the lock file a good approach or is there a better/more robust way to do this? Is using crontab for this a good idea or could I better write an endless loop with sleep()? Should I use the GNU 'daemon' program or the Perl Proc::Daemon module (or some other equivalent) for this?

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  • Generating CMakeLists.txt

    - by vanna
    I got a bunch of C++ sources files and headers. They may use external libraries such as Boost e.g. I am interested in the process of building binaries for Windows and *nix. Makefiles (*nix) and .vcproj (Windows) call compilers with some specifications such as the order of compilation, compilation options and stuff. CMakeLists.txt can be used by CMake to build either makefiles or .vcproj and use very helpful commands such as recursive search of files, automatic linkage with known libraries, installers, variables that can be used in source files... Is there any existing tool that would generate a CMakeLists.txt from specified options ? Options could be like : scan this folder and make a library out of it, then scan this other folder and make an executable and automatically link both with Boost as well along with a user friendly installer with generated INSTALL.txt and README.txt. Something very powerful like that.

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  • About Leader Board in Javascript (Array) Help Me Please

    - by raulcorrales
    Hi to all. I need help with a score table for my game. -1- I have 4 variables: var Player1Score= 44; var Player2Score= 12; var Player3Score= 45; var Player4Score= 26; --2-- i make a Array: var MyArray=[Player1Score,Player2Score,Player3Score,Player4Score]; --3-- sort the array: MyArray.Sort(); --4-- Print: ----------HIGHSCORES---------- 45 44 26 12 MY QUESTION IS: HOW I CAN PRINT THE NAME OF THE PLAYERS IN ORDER¿? LIKE THIS: ----------HIGHSCORES---------- PLAYER 3 45 PLAYER 1 44 PLAYER 4 26 PLAYER 2 12 THANKS IN ADVANCE. GREETINGS

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  • In PLT scheme, can I export functions after another function has been called?

    - by Jason Baker
    I'm trying to create a binding to libpython using scheme's FFI. To do this, I have to get the location of python, create the ffi-lib, and then create functions from it. So for instance I could do this: (module pyscheme scheme (require foreign) (unsafe!) (define (link-python [lib "/usr/lib/libpython2.6.so"]) (ffi-lib lib)) This is all well and good, but I can't think of a way to export functions. For instance, I could do something like this: (define Py_Initialize (get-ffi-obj "Py_Initialize" libpython (_fun -> _void))) ...but then I'd have to store a reference to libpython (created by link-python) globally somehow. Is there any way to export these functions once link-python is called? In other words, I'd like someone using the module to be able to do this: (require pyscheme) (link-python) (Py_Initialize) ...or this: (require pyscheme) (link-python "/weird/location/for/libpython.so") (Py_Initialize) ...but have this give an error: (require pyscheme) (Py_Initialize) How can I do this?

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  • Making a Wrapper class for ActiveMQ

    - by DarthVader
    I want to make a Wrapper class for ActiveMQ which will have only send and get functions. I want to wrap them in a static class. Users can use this client and send, get messages to the activemq instance. I want this process to be transparent. There are two classes in this link My only handicap is, i need to this in c++ and not sure where to start. I havent used c++ for ages and now not sure how I can create this wrapper class. I m giving it a try as follows: // .h file #include <stdlib.h> #include <iostream> using namespace std; class ActiveMQWrapper { public: static void send(std::string message); static std::string get(); }; // .cpp file #include<string> #include<iostream> #include "ActiveMQWrapper.h" void ActiveMQWrapper::send(std::string message){ std::cout<<message; } std::string ActiveMQWrapper::get(){ return "test"; } // test file #include <string> #include <iostream> #include "ActiveMQWrapper.h" int main() { std::string foo ="test"; ActiveMQWrapper::send(foo); std::cout<<ActiveMQWrapper::get(); return 1; } When I added the following to .h file, hell breaks loose. Do you think I should seperate this impl to a factory and initialize and instance and return to the wrapper above? How do i deal with all the dependencies? private: Connection* connection; Session* session; Destination* destination; MessageProducer* producer; int numMessages; bool useTopic; bool sessionTransacted; std::string brokerURI; and the header files, i get several messages as errors, which complains about the path. How can i get this correct? I eventually want to build a Factory, get an instance and send or get the messages to the queue. is there a code sample i can look into to get this right? essential i want to use the functionality of only this producer and consumer. Edit: I understand there is no such thing as static class in C++ . This is my reference.

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