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  • master pages, form pages, form runat=server > all onclick methods on master page?

    - by b0x0rz
    the problem i have is that i have multiple nested master pages: level 1: global (header, footer, login, navigation, etc...) level 2: specific (search pages, account pages, etc...) level 3: the page itself now, since only one form can have runat=server, i put the form at global page (so i can handle things like login, feedback, etc...). now with this solution i'd have to also put the for example level 3 (see above) methods, such as search also on the level 1 master page, but this will lead to this page being heavy (for development) with code from all places, even those that are used on a single page only (change email form for example). is there any way to delegate such methods (for example: ChangeEMail) from level 1 (global masterpage) to level 3 (the single page itself). to be even more clear: i want to NOT have to have the method ChangeEMail on the global master page code behind, but would like to 'MOVE' it somehow to the only page that will actually use it. the reason why it currently has to be on the global master is that global master has form runat=server and there can be only one of those per aspx page. this way it will be easier (more logical) to structure the code. thnx (hope i explained it correctly) have searched but did not find any general info on handling this case, usualy the answer is: have all the methods on the master page, but i don't like it. so ANY way of moving it to the specific page would be awesome. thnx

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  • Docs for auto-generated methods in Ruby on Rails

    - by macek
    Rails has all sorts of auto-generated methods that I've often times struggled to find documentation for. For example, in routes.rb, if I have: map.resources :projects do |p| p.resources :tasks end This will get a plethora of auto-generate path and url helpers. Where can I find documentation for how to work with these paths? I generally understand how to work with them, but more explicit docs might help me understand some of the magic that happens behind the scenes. # compare project_path(@project) project_task_path(@project, @task) # to project_path(:id => @project.id) project_task_path(:project_id => @project.id, :id => @task.id) Also, when I change an attribute on a model, @post.foo_changed? will be true. Where can I find documentation for this and all other magical methods that are created like this? If the magic is there, I'd love to take advantage of it. And finally: Is there a complete resource for config.___ statements for environment.rb? I was able to find docs for Configuration#gem but what attributes can I set within the stubs like config.active_record.___, config.action_mailer.___, config.action_controller.___, etc. Again, I'm looking for a complete resource here, not just a settings for the examples I provided. Even if you can only answer one of these questions, please chime in. These things seem to have been hiding from me and it's my goal to get them some more exposure, so I'll be upvoting all links to docs that point me to what I'm looking for. Thanks! ps, If they're not called auto-generated methods, I apologize. Someone can teach me a lesson here, too :) Edit I'm not looking for tutorials here, folks. I have a fair amount of experience with rails; I'm just looking for complete docs. E.g., I understand how routing works, I just want docs where I can read about all of the usage options.

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  • Generic property- specify the type at runtime

    - by Lirik
    I was reading a question on making a generic property, but I'm a little confused at by the last example from the first answer (I've included the relevant code below): You have to know the type at compile time. If you don't know the type at compile time then you must be storing it in an object, in which case you can add the following property to the Foo class: public object ConvertedValue { get { return Convert.ChangeType(Value, Type); } } That's seems strange: it's converting the value to the specified type, but it's returning it as an object when the value was stored as an object. Doesn't the returned object still require un-boxing? If it does, then why bother with the conversion of the type? I'm also trying to make a generic property whose type will be determined at run time: public class Foo { object Value {get;set;} Type ValType{get;set;} Foo(object value, Type type) { Value = value; ValType = type; } // I need a property that is actually // returned as the specified value type... public object ConvertedValue { get { return Convert.ChangeType(Value, ValType); } } } Is it possible to make a generic property? Does the return property still require unboxing after it's accessed?

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  • PHP Replace chars by functions

    - by user1860570
    I try change characters by functions <?php $string = "Hi everybody people [gal~images/articles~100~100~4] here other imagen [gal~images/products~100~100~3]"; $regex = "/\[(.*?)\]/"; preg_match_all($regex, $string, $matches); for($i=0; $i<count($matches[1]);$i++) { $match = $matches[1][$i]; $array = explode('~', $match); //$newValuet="gal("".$array[1]."","".$array[2]."","".$array[3]."","".$array[4]."")"; $newValue="gal(".$array[1].",".$array[2].",".$array[3].",".$array[4].")"; $string = str_replace($matches[0][$i],$newValue,$string); } echo $string; ?> The problem here : $newValue="gal(".$array[1].",".$array[2].",".$array[3].",".$array[4].")"; $string = str_replace($matches[0][$i],$newValue,$string); Function no give the right results i try differents methods but continue the problems , please i see all functions but no get this works if you can answer please put me some modification of this code for i can understand , thank´s a lot for all help

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  • Selectively allow unsafe html tags in Plone

    - by dhill
    I'm searching for a way to put widgets from several services (PicasaWeb, Yahoo Pipes, Delicious bookmarks, etc.) on the community site I host on Plone (currently 3.2.1). I'm looking for a way to allow a group of users to use dangerous html tags. There are some ways I see, but I don't know how to implement those. One would be changing safe_html for the pages editors own (1). Another would be to allow those tags on some subtree (2). And yet another finding an equivalent of "static text portlet" that would display in the middle panel (3). We could then use some of the composite products (I stumbled upon Collage and CMFContentPanels), to include the unsafe content on other sites. My site has been ridden by advert bots, so I don't want to remove the filtering all together. I don't have an easy (no false positives) way of checking which users are bots, so deploying captcha now wouldn't help either. The question is: How to implement any of those solutions? (I already asked that on plone mailing list without an answer, so I thought I would give it another try here.)

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  • Difference in BackgroundWorker thread access in VS2010 / .NET 4.0?

    - by Jonners
    Here's an interesting one - in VS2005 / VS2008 running against .NET 2.0 / .NET 3.0 / .NET 3.5, a BackgroundWorker thread may not directly update controls on a WinForms form that initiated that thread - you'll get a System.InvalidOperationException out of the BackgroundWorker stating "Cross-thread operation not valid: Control 'thecontrol' accessed from a thread other than the thread it was created on". I remember hitting this back in 2004 or so when I first started writing .NET WinForms apps with background threads. There are several ways around the problem - this is not a question asking for that answer. I've been told recently that this kind of operation is now allowed when written in VS2010 / .NET 4.0. This seems unlikely to me, since this kind of object access restriction has always been a fairly fundamental part of thread-safe programming. Allowing a BackgroundWorker thread direct access to objects owned not by itself but by its parent UI form seems contrary to that principle. A trawl through the .NET 4.0 docs hasn't revealed any obvious changes that could account for this behaviour. I don't have VS2010 / .NET 4.0 to test this out - does anyone who has access to that toolset know for sure whether the model has changed to allow that kind of thread interaction? I'd like to either take advantage of it in future, or deploy the cluestick. ;)

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  • Writing a VM - well formed bytecode?

    - by David Titarenco
    Hi, I'm writing a virtual machine in C just for fun. Lame, I know, but luckily I'm on SO so hopefully no one will make fun :) I wrote a really quick'n'dirty VM that reads lines of (my own) ASM and does stuff. Right now, I only have 3 instructions: add, jmp, end. All is well and it's actually pretty cool being able to feed lines (doing it something like write_line(&prog[1], "jmp", regA, regB, 0); and then running the program: while (machine.code_pointer <= BOUNDS && DONE != true) { run_line(&prog[machine.cp]); } I'm using an opcode lookup table (which may not be efficient but it's elegant) in C and everything seems to be working OK. My question is more of a "best practices" question but I do think there's a correct answer to it. I'm making the VM able to read binary files (storing bytes in unsigned char[]) and execute bytecode. My question is: is it the VM's job to make sure the bytecode is well formed or is it just the compiler's job to make sure the binary file it spits out is well formed? I only ask this because what would happen if someone would edit a binary file and screw stuff up (delete arbitrary parts of it, etc). Clearly, the program would be buggy and probably not functional. Is this even the VM's problem? I'm sure that people much smarter than me have figured out solutions to these problems, I'm just curious what they are!

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  • create an independent hidden process

    - by Jessica
    I'm creating an application with its main window hidden by using the following code: STARTUPINFO siStartupInfo; PROCESS_INFORMATION piProcessInfo; memset(&siStartupInfo, 0, sizeof(siStartupInfo)); memset(&piProcessInfo, 0, sizeof(piProcessInfo)); siStartupInfo.cb = sizeof(siStartupInfo); siStartupInfo.dwFlags = STARTF_USESHOWWINDOW | STARTF_FORCEOFFFEEDBACK | STARTF_USESTDHANDLES; siStartupInfo.wShowWindow = SW_HIDE; if(CreateProcess(MyApplication, "", 0, 0, FALSE, 0, 0, 0, &siStartupInfo, &piProcessInfo) == FALSE) { // blah return 0; } Everything works correctly except my main application (the one calling this code) window loses focus when I open the new program. I tried lowering the priority of the new process but the focus problem is still there. Is there anyway to avoid this? furthermore, is there any way to create another process without using CreateProcess (or any of the API's that call CreateProcess like ShellExecute)? My guess is that my app is losing focus because it was given to the new process, even when it's hidden. To those of you curious out there that will certainly ask the usual "why do you want to do this", my answer is because I have a watchdog process that cannot be a service and it gets started whenever I open my main application. Satisfied? Thanks for the help. Code will be appreciated. Jess.

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  • Yii user rights extension

    - by jailed abroad
    i have installed the yii rights extension and here is my code after installation, database tables are created after installation. 'modules'=>array( // uncomment the following to enable the Gii tool 'rights'=>array( 'superuserName'=>'Admin', // Name of the role with super user privileges. 'authenticatedName'=>'Authenticated', //// Name of the authenticated user role. 'userIdColumn'=>'id',// Name of the user id column in the database. 'userNameColumn'=>'username', // Name of the user name column in the database. 'enableBizRule'=>true, // Whether to enable authorization item business rules. 'enableBizRuleData'=>false, //Whether to enable data for business rules. 'displayDescription'=>true, // Whether to use item description instead of name. ' // Key to use for setting success flash messages. 'flashErrorKey'=>'RightsError', / Key to use for setting error flash messages. // 'install'=>true, // Whether to install rights. 'baseUrl'=>'/rights', // Base URL for Rights. Change if module is nested. 'layout'=>'rights.views.layouts.main', // Layout to use for displaying Rights. 'appLayout'=>'application.views.layouts.main', //Application layout. 'cssFile'=>'rights.css', // Style sheet file to use for Rights. ' 'install'=>false, // Whether to enable installer. 'debug'=>false, ), 'gii'=>array( 'class'=>'system.gii.GiiModule', 'password'=>'1234', // If removed, Gii defaults to localhost only. Edit carefully to taste. 'ipFilters'=>array('127.0.0.1','::1'), ), ), But when i type url http://localhost/rightsTest/index.php/rights then it says There must be at least one superuser! I have tried many things but unable to find answer. Thanks for your help.

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  • In Inform 7, is it possible to use a second noun construct with "pull"?

    - by Beska
    I'll eat my hat if I get a good answer to this...I suspect that although I'm a rank beginner in Inform 7, and I'm guessing this isn't that hard, but there are probably not many people here who are familiar with Inform 7. Still, nothing ventured... I'm trying to create a custom response to a "pull" action. Unfortunately, I think the "pull" action doesn't normally expect a second noun. So I'm trying something like this: The nails are some things in the Foyer. The nails are scenery. Instead of pulling the nails: If the second noun is nothing: say "How? Are you going to pull the nails with your teeth?"; otherwise: say "I don't think that's going to do the job." But while this compiles, and the first part works, the "I don't think..." section is never called...the interpreter just responds "I only understood you as far as wanting to pull the nails." Do I have to create my own custom action for this? Overwrite the standard pull action? Am I missing something simple that will allow me to get this to work?

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  • Fetching Strategy example in repository pattern with pure POCO Entity framework

    - by Shawn Mclean
    I'm trying to roll out a strategy pattern with entity framework and the repository pattern using a simple example such as User and Post in which a user has many posts. From this answer here, I have the following domain: public interface IUser { public Guid UserId { get; set; } public string UserName { get; set; } public IEnumerable<Post> Posts { get; set; } } Add interfaces to support the roles in which you will use the user. public interface IAddPostsToUser : IUser { public void AddPost(Post post); } Now my repository looks like this: public interface IUserRepository { User Get<TRole>(Guid userId) where TRole : IUser; } Strategy (Where I'm stuck). What do I do with this code? Can I have an example of how to implement this, where do I put this? public interface IFetchingStrategy<TRole> { TRole Fetch(Guid id, IRepository<TRole> role) } My basic problem was what was asked in this question. I'd like to be able to get Users without posts and users with posts using the strategy pattern.

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  • how to dispaly image in grid view reading imageUrl from xml using sax parser in android

    - by Pramod kuamr
    thanks for answer but i am able to read xml file from url but i need if in xml imageUrl is there so show in grid view ..this is my xml file and read URL <?xml version="1.0" encoding="UTF-8"?> <channels> <channel> <name>ndtv</name> <logo>http://a3.twimg.com/profile_images/670625317/aam-logo--twitter.png</logo> <description>this is a news Channel</description> <rssfeed>ndtv.com</rssfeed> </channel> <channel> <name>star news</name> <logo>http://a3.twimg.com/profile_images/740897825/AndroidCast-350_normal.png</logo> <description>this is a newsChannel</description> <rssfeed>starnews.com</rssfeed> </channel> </channels>

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  • Wordpress: How to override all default theme CSS so your custom one is loaded the last?

    - by mickael
    I have a problem where I've been able to include a custom css in the section of my wordpress theme with the following code: function load_my_style_wp_enqueue_scripts() { wp_register_style('my_styles_css', includes_url("/css/my_styles.css")); wp_enqueue_style('my_styles_css'); } add_action('wp_enqueue_scripts','load_my_style_wp_enqueue_scripts'); But the order in the source code is as follows: <link rel='stylesheet' id='my_styles_css-css' href='http://...folderA.../my_styles.css?ver=3.1' type='text/css' media='all' /> <link rel="stylesheet" id="default-css" href="http://...folderB.../default.css" type="text/css" media="screen,projection" /> <link rel="stylesheet" id="user-css" href="http://...folderC.../user.css" type="text/css" media="screen,projection" /> I want my_styles_css to be the last file to load, overriding default and user files. I've tried to achieve this by modifying wp_enqueue_style in different ways, but without any success. I've tried: wp_enqueue_style('my_styles_css', array('default','user')); or wp_enqueue_style('my_styles_css', false, array('default','user'), '1.0', 'all'); I've seen some related questions without answer or with these last 2 methods that are still failing for me. The function above is part of a plugin that I've got enabled in my wordpress installation.

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  • How to have an iCalendar (RFC 2445) repeat YEARLY with duration

    - by Todd Brooks
    I have been unsuccessful in formulating a RRULE that would allow an event as shown below: Repeats YEARLY, from first Sunday of April to last day of May, occuring on Monday, Wednesday and Friday, until forever. FREQ=YEARLY;BYMONTH=4;BYDAY=SU (gives me the first Sunday of April repeating yearly) and FREQ=YEARLY;BYMONTH=5;BYMONTHDAY=-1 (gives me the last day of May repeating yearly) But I can't figure out how to have the event repeat yearly between those dates for Monday, Wednesday and Friday. Suggestions? Update: Comments don't have enough space to respond to Chris' answer, so I am editing the question with further information. Unfortunately, no. I don't know if it is the DDay.iCal library I'm using, or what, but that doesn't work either. I've found that the date start can't be an ordinal date (first Sunday, etc.)..it has to be a specific date, which makes it difficult for my requirements. Even using multiple RRULE's it doesn't seem to work: BEGIN:VCALENDAR VERSION:2.0 PRODID:-//DDay.iCal//NONSGML ddaysoftware.com//EN BEGIN:VEVENT CREATED:20090717T033307Z DTSTAMP:20090717T033307Z DTSTART:20090101T000000 RRULE:FREQ=YEARLY;WKST=SU;BYDAY=MO,WE,FR;BYMONTH=4,5 RRULE:FREQ=YEARLY;WKST=SU;BYDAY=1SU;BYMONTH=4 RRULE:FREQ=YEARLY;WKST=SU;BYMONTH=5;BYMONTHDAY=-1 SEQUENCE:0 UID:352ed9d4-04d0-4f06-a094-fab7165e5c74 END:VEVENT END:VCALENDAR That looks right on the face (I'm even starting the event on 1/1/2009), but when I start testing whether certain days are valid, I get incorrect results. For example, 4/1/2009 12:00:00 AM = True // Should be False 4/6/2009 12:00:00 AM = True 4/7/2009 12:00:00 AM = False 4/8/2009 12:00:00 AM = True 5/1/2009 12:00:00 AM = True 5/2/2009 12:00:00 AM = False 5/29/2009 12:00:00 AM = True 5/31/2009 12:00:00 AM = True // Should be False 6/1/2009 12:00:00 AM = False I'm using Douglas Day's DDay.iCal software, but I don't think it is a bug in that library. I think this might be a limitation in iCalendar (RFC 2445). Thoughts?

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  • Game architecture: modeling different steps/types of UI

    - by Sander
    I have not done any large game development projects, only messed around with little toy projects. However, I never found an intuitive answer to a specific design question. Namely, how are different types/states of UI modeled in games? E.g. how is a menu represented? How is it different from a "game world" state (let's use an FPS as an example). How is an overlaid menu on top of a "game world" modeled? Let's imagine the main loop of a game. Where do the game states come into play? It it a simple case-by-case approach? if (menu.IsEnabled) menu.Process(elapsedTime); if (world.IsEnabled) world.Process(elapsedTime); if (menu.IsVisible) menu.Draw(); if (world.IsVisible) world.Draw(); Or are menu and world represented somewhere in a different logic layer and not represented at this level? (E.g. a menu is just another high-level entity like e.g. player input or enemy manager, equal to all others) foreach (var entity in game.HighLevelEntities) entity.Process(elapsedTime); foreach (var entity in game.HighLevelEntities) entity.Draw(elapsedTime); Are there well-known design patterns for this? Come to think of it, I don't know any game-specific design patterns - I assume there are others, as well? Please tell me about them.

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  • Choosing between instance methods and separate functions?

    - by StackedCrooked
    Adding functionality to a class can be done by adding a method or by defining a function that takes an object as its first parameter. Most programmers that I know would choose for the solution of adding a instance method. However, I sometimes prefer to create a separate function. For example, in the example code below Area and Diagonal are defined as separate functions instead of methods. I find it better this way because I think these functions provide enhancements rather than core functionality. Is this considered a good/bad practice? If the answer is "it depends", then what are the rules for deciding between adding method or defining a separate function? class Rect { public: Rect(int x, int y, int w, int h) : mX(x), mY(y), mWidth(w), mHeight(h) { } int x() const { return mX; } int y() const { return mY; } int width() const { return mWidth; } int height() const { return mHeight; } private: int mX, mY, mWidth, mHeight; }; int Area(const Rect & inRect) { return inRect.width() * inRect.height(); } float Diagonal(const Rect & inRect) { return std::sqrt(std::pow(static_cast<float>(inRect.width()), 2) + std::pow(static_cast<float>(inRect.height()), 2)); }

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  • Bookmarkable URLs after Ajax for Wicket

    - by Wolfgang
    There is this well-known problem that browsers don't put Ajax request in the request history and cause problems for bookmarkability, forward/back button, and refresh. Also, there is a common solution to that problem that appends the hash symbol # and some additional parameters to the URL by using Javascript window.location.hash = .... In this question a basic solution to this problem is proposed, for example. = My question is if such a solution has been integrated in Wicket, so that existing Wicket facilities are used and no custom Javascript had to be added. If not, I'd be interested in how this could be done. Such a solution had to answer the question what should be put after the hash. I like the idea that the bookmarkable URL that (in the non-Ajax case) were in front of the hash could be put behind it. For example, when you are on http://host/catalog and reach a page http://host/product/xyz the Ajax-triggered URL would be http://host/catalog#/product/xyz. Then it would be easy to write an onload handler that checks for the # and does a redirect to the URL after the hash.

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  • WPF ContextMenu bind some property to another property of the same control

    - by bebicasoft
    I have a ContextMenu and a ColumnHeaderStyle defined in Window.Resource section witch i use-it to a DataGrid ColumnHeader. My code is something like this: <ContextMenu x:Key="cm_columnHeaderMenu"/> <Style x:Key="DefaultColumnHeaderStyle" TargetType="{x:Type DataGridColumnHeader}"> <Setter Property="ContextMenu" Value="{StaticResource cm_columnHeaderMenu}" /> </Style> <DataGrid Grid.Column="2" Grid.Row="1" x:Name="dgridFiles" IsReadOnly="True" ColumnHeaderStyle="{StaticResource DefaultColumnHeaderStyle}"> I want to know if I can (and if the answer it true, then HOW I could do it) bind the ContextMenu Visibility property to same control ContextMenu Items.Count>0 property. Initially based on some other treeView control selections made there shoud be no items in the context menu, but i wish to add dinamically items in ContextMenu based on selection in treeView. This part is done, the context has those items. On some selections there are no-items, but still on the grid it appears an empty ContextMenu. So I believe the easiest part it would be to bind the Visibility to Items.Count property of the same control. Sorry if my english is not good enought, I'll try to explain better if i didnt make clear 1st time.

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  • Using StructureMap to create classes by a name?

    - by Bevan
    How can I use StructureMap to resolve to an appropriate implementation of an interface based on a name stored in an attribute? In my project, I have many different kinds of widgets, each descending from IWidget, and each decorated with an attribute specifying the kind of associated element. To illustrate: [Configuration("header")] public class HeaderWidget : IWidget { } [Configuration("linegraph")] public class LineGraphWidget : IWidget { } When processing my (XML) configuration file, I want to obtain an instance of the appropriate concrete class based on the name of the element I'm processing. public IWidget CreateWidget(XElement definition) { var kind = definition.Name.LocalName; var widget = // What goes here? widget.Configure(definition); return widget; } Each definition should result in a different widget being created - I don't need or want the instances to be shared. In the past I've written plenty of code to do this kind of thing manually, including writing a custom "roll-your-own" IoC container for one project. However, one of my goals with this project is to become proficient with StructureMap instead of reinventing the wheel. I think I've already managed to set up automatic scanning of assemblies so that StructureMap knows about all my IWidget implementations: public class WidgetRegistration : Registry { public WidgetRegistration() { Scan( scanner => { scanner.AssembliesFromApplicationBaseDirectory(); scanner.AddAllTypesOf<IWidget>(); }); } } However, this isn't registering the names of my widgets with StructureMap. What do I need to add to make my scenario work? (While I am trying to use StructureMap in this project, an answer showing me how to solve this problem with a different DI/IoC tool would still be valuable.)

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  • How do I ensure a Flex dataProvider processes the data synchronously?

    - by Matt Calthrop
    I am using an component, and currently have a dataProvider working that is an ArrayCollection (have a separate question about how to make this an XML file... but I digress). Variable declaration looks like this: [Bindable] private var _dpImageList : ArrayCollection = new ArrayCollection([ {"location" : "path/to/image1.jpg"}, {"location" : "path/to/image2.jpg"}, {"location" : "path/to/image3.jpg"} ]); I then refer to like this: <s:List id="lstImages" width="100%" dataProvider="{_dpImageList}" itemRenderer="path.to.render.ImageRenderer" skinClass="path.to.skins.ListSkin" > <s:layout> <s:HorizontalLayout gap="2" /> </s:layout> </s:List> Currently, it would appear that each item is processed asynchronously. However, I want them to be processed synchronously. Reason: I am displaying a list of images, and I want the leftmost one rendered first, followed by the one to its right, and so on. Edit: I just found this answer. Do you think that could be the same issue?

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  • questions on nfa and dfa..

    - by Loop
    Hi Guys... Hope you help me with this one.... I have a main question which is ''how to judge whether a regular expression will be accepted by NFA and/or DFA? For eg. My question says that which of the regular expressions are equivalent? explain... 1.(a+b)*b(a+b)*b(a+b)* 2.a*ba*ba* 3.a*ba*b(a+b)* do we have to draw the NFA and DFA and then find through minimisation algorithm? if we do then how do we come to know that which regular expression is accepted by NFA/DFA so that we can begin with the answer? its so confusing.... Second is a very similar one, the question asks me to show that the language (a^nb^n|n1} is not accepted by DFA...grrrrr...how do i know this? (BTW this is a set of all strings of where a number of a's is followed by the same number of b's).... I hope I explained clearly well....

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  • C++0x rvalue references and temporaries

    - by Doug
    (I asked a variation of this question on comp.std.c++ but didn't get an answer.) Why does the call to f(arg) in this code call the const ref overload of f? void f(const std::string &); //less efficient void f(std::string &&); //more efficient void g(const char * arg) { f(arg); } My intuition says that the f(string &&) overload should be chosen, because arg needs to be converted to a temporary no matter what, and the temporary matches the rvalue reference better than the lvalue reference. This is not what happens in GCC and MSVC. In at least G++ and MSVC, any lvalue does not bind to an rvalue reference argument, even if there is an intermediate temporary created. Indeed, if the const ref overload isn't present, the compilers diagnose an error. However, writing f(arg + 0) or f(std::string(arg)) does choose the rvalue reference overload as you would expect. From my reading of the C++0x standard, it seems like the implicit conversion of a const char * to a string should be considered when considering if f(string &&) is viable, just as when passing a const lvalue ref arguments. Section 13.3 (overload resolution) doesn't differentiate between rvalue refs and const references in too many places. Also, it seems that the rule that prevents lvalues from binding to rvalue references (13.3.3.1.4/3) shouldn't apply if there's an intermediate temporary - after all, it's perfectly safe to move from the temporary. Is this: Me misreading/misunderstand the standard, where the implemented behavior is the intended behavior, and there's some good reason why my example should behave the way it does? A mistake that the compiler vendors have somehow all made? Or a mistake based on common implementation strategies? Or a mistake in e.g. GCC (where this lvalue/rvalue reference binding rule was first implemented), that was copied by other vendors? A defect in the standard, or an unintended consequence, or something that should be clarified?

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  • Is there really such a thing as a char or short in modern programming?

    - by Dean P
    Howdy all, I've been learning to program for a Mac over the past few months (I have experience in other languages). Obviously that has meant learning the Objective C language and thus the plainer C it is predicated on. So I have stumbles on this quote, which refers to the C/C++ language in general, not just the Mac platform. With C and C++ prefer use of int over char and short. The main reason behind this is that C and C++ perform arithmetic operations and parameter passing at integer level, If you have an integer value that can fit in a byte, you should still consider using an int to hold the number. If you use a char, the compiler will first convert the values into integer, perform the operations and then convert back the result to char. So my question, is this the case in the Mac Desktop and IPhone OS environments? I understand when talking about theses environments we're actually talking about 3-4 different architectures (PPC, i386, Arm and the A4 Arm variant) so there may not be a single answer. Nevertheless does the general principle hold that in modern 32 bit / 64 bit systems using 1-2 byte variables that don't align with the machine's natural 4 byte words doesn't provide much of the efficiency we may expect. For instance, a plain old C-Array of 100,000 chars is smaller than the same 100,000 ints by a factor of four, but if during an enumeration, reading out each index involves a cast/boxing/unboxing of sorts, will we see overall lower 'performance' despite the saved memory overhead?

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  • activemerchant PayPalExpress transaction is invalid

    - by Ameya Savale
    I am trying to integrate activemerchant into my ruby on rails application. This is my controller where I get the purchase attirbutes and create a PaypalExpressResponse object def checkout total_as_cents, purchase_params = get_setup_params(Schedule.find(params[:schedule]), request) setup_response = @gateway.setup_purchase(total_as_cents, purchase_params) redirect_to @gateway.redirect_url_for(setup_response.token) end @gateway is my PaypalExpressGateway object which I create using this method in my controller def assign_gateway @gateway = PaypalExpressGateway.new( :login => api_user, :password => api_pass, :signature => api_signature ) end I got the api_user, api_pass, and api_signature values from my developer.paypal.com account, when I logged in for the first time there was already a sandbox user created as a merchant which is where I got the api credentials from. And finally here is my get_setup_params method: def get_setup_params(schedule, request) purchase_params = { :ip => request.remote_ip, :return_url => url_for(:action => 'review', :only_path => false, :sched => schedule.id), :cancel_return_url => register_path, :allow_note => true, :item => schedule.id } return to_cents(schedule.fee), purchase_params end How ever when I click on the checkout button, I get redirected to a sandbox paypal page saying "This transaction is invalid. Please return to the recipient's website to complete your transaction using their regular checkout flow." I'm not sure exactly what's wrong, I think the problem lies in the credentials but don't know why. Any help will be appreciated. One other point, I'm running this in my development environment so I have put this in my config file config.after_initialize do ActiveMerchant::Billing::Base.mode = :test end UPDATE Found out what the problem was, my return cancel url was invalid instead of using register_path, I used url_for(action: "action-name", :only_path => false) this answer helped me Rails ActiveMerchant - Paypal Express Checkout Error even though I wasn't able to see the output of the response like the person has managed to do

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  • Paperclip failing to upload on specific scaffold, yet works on others

    - by Saifis
    I know there are tons of questions about paperclip, but I failed to find the answer to my problem. I know its prob just something simple, but I I'm running out of hair to pull out. I have paperclip working on other parts of my project, they work with no problem, however, a certain scaffold fails to upload, all the attributes to the uploaded file are nil. Here are the relevant information. Model: has_attached_file :foo, :styles => { :thumb => "140x140>" }, :url => "/data/:id/:style/:basename.:extension", :path => ":rails_root/public/data/:id/:style/:basename.:extension" View: <% form_for(@bar, :html => { :multipart => true }) do |f| %> <%= f.error_messages %> ---------- <li><%= f.label :top %> <%= f.file_field :foo %></li> ---------- <ul><%= f.submit "Save" %></ul> <% end %> Also, comparing the logs to the parts that work, the :foo attribute seems to be passing different values than in the ones that work. In the logs, when the paperclip function works, it looks like this "image"=>#<File:/var/folders/M5/M5HEb+WhFxmqNDGH5s-pNE+++TI/-Tmp-/RackMultipart20100512-1302-5e2e6e-0> when it does not, it seems to pass the file name directly "foo"=>"foo_image.png" I am developing locally on MacOSX using local rails and ruby libs.

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