Search Results

Search found 23427 results on 938 pages for 'christopher done'.

Page 139/938 | < Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >

• Cocoa Services Programming - How to identify whether the selected item is a folder or file wih NSFi

  - by rockybalboa

  Hi , I have some queries regarding Services menu validation . I would like to enable different services provided by my app based on whether a file or folder is selected in the Finder. I have set NSFilenamesPboardType as the send type for the services . I have gone through the - (id)validRequestorForSendType:(NSString *)sendType returnType:(NSString *)returnType method but my issue is that the validation there seems to be done based on the sendType and return type. In my case , the selected file and folder pasteboard type is the same and I cannot determine whether the selected item in the Finder is a file or folder during the validation process ( This is before the actual service gets invoked i.e when the services menu is being shown to the user ) ? So my question is that is there any way I can get some info about the selected item in the Finder and validate the different service menus offered by my application based on some info regarding the item rather than the basic validation of the send and return types ? I am not able to find out any manner to do so but "Folder Actions" service in Snow Leopard gets enabled only for folders so it can be done. I did a /System/Library/CoreServices/pbs -dump_pboard and it is using a NSFilenamePBoardType also yet manages to activate only for folders. Thanks in advace for any help .

  Read the article

• How to make a wxFrame behave like a modal wxDialog object

  - by dagorym

  Is is possible to make a wxFrame object behave like a modal dialog box in that the window creating the wxFrame object stops execution until the wxFrame object exits? I'm working on a small game and have run into the following problem. I have a main program window that hosts the main application (strategic portion). Occasionally, I need to transfer control to a second window for resolution of part of the game (tactical portion). While in the second window, I want the processing in the first window to stop and wait for completion of the work being done in the second window. Normally a modal dialog would do the trick but I want the new window to have some functionality that I can't seem to get with a wxDialog, namely a status bar at the bottom and the ability to resize/maximize/minimize the window (this should be possible but doesn't work, see this question How to get the minimize and maximize buttons to appear on a wxDialog object). As an addition note, I want the second window's functionality needs to stay completely decoupled from the primary window as it will be spun off into a separate program eventually. Has anyone done this or have any suggestions?

  Read the article

• Technical choices in unmarshaling hash-consed data

  - by Pascal Cuoq

  There seems to be quite a bit of folklore knowledge floating about in restricted circles about the pitfalls of hash-consing combined with marshaling-unmarshaling of data. I am looking for citable references to these tidbits. For instance, someone once pointed me to library aterm and mentioned that the authors had clearly thought about this and that the representation on disk was bottom-up (children of a node come before the node itself in the data stream). This is indeed the right way to do things when you need to re-share each node (with a possible identical node already in memory). This re-sharing pass needs to be done bottom-up, so the unmarshaling itself might as well be, too, so that it's possible to do everything in a single pass. I am in the process of describing difficulties encountered in our own context, and the solutions we found. I would appreciate any citable reference to the kind of aforementioned folklore knowledge. Some people obviously have encountered the problems before (the aterm library is only one example). But I didn't find anything in writing. Even the little piece of information I have about aterm is hear-say. I am not worried it's not reliable (you can't make this up), but "personal communication" and "look how it's done in the source code" are considered poor form in citations. I have enough references on hash-consing alone. I am only interested in references where it interferes with other aspects of programming, such as marshaling or distribution.

  Read the article

• IIS7 integrated mode MVC deploy 404 not found on some actions

  - by majkinetor

  Hello. Once deployed parts of my web-application stop working. Index-es on each controller do work, and one form posting via Ajax, other then that yields 404. I understand that nothing particular should be done in integrated mode. One interesting thing is that 1 AJAX action is working. I don't know how to proceed with troubleshooting. Some info: App is using default app pool set to integrated mode. WebApp is done in net framework 3.5. I use default routing model. Along web.config in root there is web.config in /View folder referencing HttpNotFoundHandler. OS is Windows Server 2008. Admins issued aspnet_regiis.exe -i IIS 7 Any help is appreciated. Thx. EDIT: Noticed one very strange thing. One ajax call works, other ajax call doesn't works as I login, but when I move to ther page and return to that one it starts working ?! Small video of the problem is available here

  Read the article

• How do I install websocket module for Node.js on Debian VPS?

  - by Ollie Shaw

  I currently am renting a VPS from Dreamhost which runs Debian. I am still learning command line on this OS, but fast! I have successfully installed Node.js, now I want to install the websocket module found here: https://github.com/Worlize/WebSocket-Node From the root user, I have run the following command: npm install websocket The error thrown is: [websocket v1.0.7] Native code compile failed!! On Windows, native extensions require Visual Studio and Python. On Unix, native extensions require Python, make and a C++ compiler. Start npm with --websocket:verbose to show compilation output (if any). What commands should I issue to install this websocket module and its requirements? Thanks very much! Edit: When I run sudo apt-get install gcc make I get this message: Reading package lists... Done Building dependency tree Reading state information... Done gcc is already the newest version. gcc set to manually installed. make is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 44 not upgraded. And the same error when trying to install WebSocket.

  Read the article

• Question about compilers and how they work

  - by Marin Doric

  This is the C code that frees memory of a singly linked list. It is compiled with Visual C++ 2008 and code works as it should be. /* Program done, so free allocated memory */ current = head; struct film * temp; temp = current; while (current != NULL) { temp = current->next; free(current); current = temp; } But I also encountered ( even in a books ) same code written like this: /* Program done, so free allocated memory */ current = head; while (current != NULL) { free(current); current = current->next; } If I compile that code with my VC++ 2008, program crashes because I am first freeing current and then assigning current-next to current. But obviously if I compile this code with some other complier ( for example, compiler that book author used ) program will work. So question is, why does this code compiled with specific compiler work? Is it because that compiler put instructions in binary file that remember address of current-next although I freed current and my VC++ doesn't. I just want to understand how compilers work.

  Read the article

• UIActivityIndicatorView in a class without a view

  - by Structurer

  Hi I have defined a class that does a lengthy task and I call it from several other classes. Now I want to show an Activity Indicator while this task is doing it's thing, and then remove it once it's done. Since this is just a boring background task, this class doesn't have a view, and I guess that is where I run into my problem. I can't get this thing to show. This is what I have done in my class: UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 32.0f, 32.0f)]; [activityIndicator setCenter:CGPointMake(160.0f, 208.0f)]; activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhite; UIView *contentView = [[UIView alloc]initWithFrame:[[UIScreen mainScreen] applicationFrame]]; [contentView addSubview:activityIndicator]; [activityIndicator startAnimating]; // Do the class lengthy task that takes several seconds..... [contentView release]; [activityIndicator release]; I guess I do something wrong when I get the contentView, but how should I get it properly? Thanks for any advices...

  Read the article

• Any merit to a lazy-ish juxt function?

  - by NielsK

  In answering a question about a function that maps over multiple functions with the same arguments (A: juxt), I came up with a function that basically took the same form as juxt, but used map: (defn could-be-lazy-juxt [& funs] (fn [& args] (map #(apply %1 %2) funs (repeat args)))) => ((juxt inc dec str) 1) [2 0 "1"] => ((could-be-lazy-juxt inc dec str) 1) (2 0 "1") => ((juxt * / -) 6 2) [12 3 4] => ((could-be-lazy-juxt * / -) 6 2) (12 3 4) As posted in the original question, I have little clue about the laziness or performance of it, but timing in the REPL does suggest something lazy-ish is going on. => (time (apply (juxt + -) (range 1 100))) "Elapsed time: 0.097198 msecs" [4950 -4948] => (time (apply (could-be-lazy-juxt + -) (range 1 100))) "Elapsed time: 0.074558 msecs" (4950 -4948) => (time (apply (juxt + -) (range 10000000))) "Elapsed time: 1019.317913 msecs" [49999995000000 -49999995000000] => (time (apply (could-be-lazy-juxt + -) (range 10000000))) "Elapsed time: 0.070332 msecs" (49999995000000 -49999995000000) I'm sure this function is not really that quick (the print of the outcome 'feels' about as long in both). Doing a 'take x' on the function only limits the amount of functions evaluated, which probably is limited in it's applicability, and limiting the other parameters by 'take' should be just as lazy in normal juxt. Is this juxt really lazy ? Would a lazy juxt bring anything useful to the table, for instance as a compositing step between other lazy functions ? What are the performance (mem / cpu / object count / compilation) implications ? Is that why the Clojure juxt implementation is done with a reduce and returns a vector ? Edit: Somehow things can always be done simpler in Clojure. (defn could-be-lazy-juxt [& funs] (fn [& args] (map #(apply % args) funs)))

  Read the article

• Unable to create a breakpoint in Eclipse and Tomcat

  - by Traroth

  Since yesterday, I get a strange error message when I start my Tomcat (6.0.35) under Eclipse Juno (build 20120614-1722): Among the things I tried in order to get rid of the error: Check in Preferences - Java - Compiler if all "Classfile Generation" checkboxes where checked. I did that for both general preferences and project preference Uncheck them, build, check them build again (found on another question) Add org.eclipse.jdt.core.compiler.debug.lineNumber=generate to my .settings/org.eclipse.jdt.core.prefs file Use a new CVS checkout (same symptoms) And now, I don't know what to do anymore. The problem is really stopping me from get anything done. I can't work anymore. Crazy is: the problem doesn't happen on every class, only on some of them. Neither does it happen on my other Eclipse projects. And it didn't happen before yesterday, even if I can't remeber having done anything weird. Actually, I have never seen a problem like this in almost 10 years I'm using Eclipse... If you have any idea, I would be really grateful... Edit: I also tried to ignore the message and go on with my tests: If I create another breakpoint upstream from my problematic class, when I enter this problematic class, it tries to open a $Proxy132 class, which means it actually opens an empty page, with a source not found message

  Read the article

• confused about how to use JSON in C#

  - by Josh

  The answer to just about every single question about using C# with json seems to be "use JSON.NET" but that's not the answer I'm looking for. the reason I say that is, from everything I've been able to read in the documentation, JSON.NET is basically just a better performing version of the DataContractSerializer built into the .net framework... Which means if I want to deserialize a JSON string, I have to define the full, strongly-typed class for EVERY request I might have. so if I have a need to get categories, posts, authors, tags, etc, I have to define a new class for every one of these things. This is fine if I built the client and know exactly what the fields are, but I'm using someone else's api, so I have no idea what the contract is unless I download a sample response string and create the class manually from the JSON string. Is that the only way it's done? Is there not a way to have it create a kind of hashtable that can be read with json["propertyname"]? Finally, if I do have to build the classes myself, what happens when the API changes and they don't tell me (as twitter seems to be notorious for doing)? I'm guessing my entire project will break until I go in and update the object properties... So what exactly is the general workflow when working with JSON? And by general I mean library-agnostic. I want to know how it's done in general, not specifically to a target library... I hope that made sense, this has been a very confusing area to get into... thanks!

  Read the article

• How To Go About Updating Old C Code

  - by Ben313

  Hello: I have been working on some 10 year old C code at my job this week, and after implementing a few changes, I went to the boss and asked if he needed anything else done. Thats when he dropped the bomb. My next task was to go through the 7000 or so lines and understand more of the code, AND, to modularize the code somewhat. I asked him how he would like the source code modularized, and he said to start putting the old C code into c++ classes. Being a good worker, I nodded my head yes, and went back to my desk, where I sit now, wondering how in the world to take this code, and "modularize" it. Its already in 20 source files, each with its own purpose and function. in addition, there are three "main" structs. each of these stuctures has 30 plus fields, many of them being other, smaller sturcts. Its a complete mess to try to understand, but almost every single function in the program is passed a pointer to one of the structs, and uses the struct heavily. Is there any clean way for me to shoehorn this into classes? I am resolved to do it if it can be done, I just have no idea how to begin.

  Read the article

• Windows Service Installation

  - by Goober

  Scenario I have a server, that has NO Visual Studio Installed. It literally has a normal command prompt and nothing installed yet. We don't want to install anything (except the .Net framework which we have already done). We just want to install a bunch of C# Windows Services that we have written. So far I have been installing and running the windows service on my local machine using a "setup and deploy" project that I built into the application, which I could then use to install the service locally. Question How can I install the service on the server? I imagine it can be done from the command prompt only, but what else do I need? - If anything? and where do I put the files that I want to install BEFORE I install them? I imagine I will have to compile the application on my local machine in Visual Studio, then copy it over to the server, and then run an install utility to install it on the server? Any help would be greatly appreciated.

  Read the article

• Convert Google Analytics cookies to Local/Session Storage

  - by David Murdoch

  Google Analytics sets 4 cookies that will be sent with all requests to that domain (and ofset its subdomains). From what I can tell no server actually uses them directly; they're only sent with __utm.gif as a query param. Now, obviously Google Analytics reads, writes and acts on their values and they will need to be available to the GA tracking script. So, what I am wondering is if it is possible to: rewrite the __utm* cookies to local storage after ga.js has written them delete them after ga.js has run rewrite the cookies FROM local storage back to cookie form right before ga.js reads them start over Or, monkey patch ga.js to use local storage before it begins the cookie read/write part. Obviously if we are going so far out of the way to remove the __utm* cookies we'll want to also use the Async variant of Analytics. I'm guessing the down vote was because I didn't ask a question. DOH! My questions are: Can it be done as described above? If so, why hasn't it been done? I have a default HTML/CSS/JS boilerplate template that passes YSlow, PageSpeed, and Chrome's Audit with near perfect scores. I'm really looking for a way to squeeze those remaining cookie bytes from Google Analytics in browsers that support local storage.

  Read the article

• c# string interning

  - by CodingThunder

  I am trying to understand string interning and why is doesn't seem to work in my example. The point of the example is to show Example 1 uses less (a lot less memory) as it should only have 10 strings in memory. However, in the code below both example use roughly the same amount of memory (virtual size and working set). Please advice why example 1 isn't using a lot less memory? Thanks Example 1: IList<string> list = new List<string>(10000); for (int i = 0; i < 10000; i++) { for (int k = 0; k < 10; k++) { list.Add(string.Intern(k.ToString())); } } Console.WriteLine("intern Done"); Console.ReadLine(); Example 2: IList<string> list = new List<string>(10000); for (int i = 0; i < 10000; i++) { for (int k = 0; k < 10; k++) { list.Add(k.ToString()); } } Console.WriteLine("intern Done"); Console.ReadLine();

  Read the article

• how do i parse an xml page to output its data pieces to the way i want?

  - by ida

  here is the page i want to parse (the api link i gave is just a dev test so its ok to be public) http://api.scribd.com/api?method=docs.getList&api_key=2apz5npsqin3cjlbj0s6m the output im looking for is something like this (for now) Doc_id: 29638658 access_key: key-11fg37gwmer54ssq56l3 secret_password: 1trinfqri6cnv3gf6rnl title: Sample description: k thumbnail_url: http://i6.scribdassets.com/public/images/uploaded/152418747/xTkjCwQaGf_thumbnail.jpeg page_count: 100 ive tried everything i can find on the internet but nothing works good. i have this one script <?php $xmlDoc = new DOMDocument(); $xmlDoc->load("http://api.scribd.com/api?method=docs.getList&api_key=2apz5npsqin3cjlbj0s6m"); $x = $xmlDoc->documentElement; foreach ($x->childNodes AS $item) { print $item->nodeName . " = " . $item->nodeValue; } ?> its output comes out like this: #text = resultset = 29638658 key-11fg37gwmer54ssq56l3 1trinfqri6cnv3gf6rnl Sample k http://i6.scribdassets.com/public/images/uploaded/152418747/xTkjCwQaGf_thumbnail.jpeg DONE 100 29713260 key-18a9xret4jf02129vlw8 25fjsmmvl62l4cbwd1vq book2 description bla bla http://i6.scribdassets.com/public/images/uploaded/153065528/oLVqPZMu3zhsOn_thumbnail.jpeg DONE 7 #text = i need major help im really stuck and dont know what to do. please please help me. thnx

  Read the article

• Really cool way to create custom UITabBar for iPhone app?

  - by ludicco

  Hi, I am doing a lot of researching lately about how to get a different looking with nice effects UITabBar on my iPhone app, but unfortunately I am only finding things on how to replace background color etc. Well, I've checked out this app called Momento which is pretty cool and presents a very slick tabBar: So there are a couple of elements here I would like to ask you guys if you could help me by giving me the right directions on how to get a similar effect :) Arrow above items: as you can see this app has this animated arrow that runs above the selected item with a very smooth animation. Selected Stated of the item's image is not that blue-ish default one neither the default state which displays in a different shade of brown and gray version. nice Items separators with beveled vertical lines. diferrent background image for the tabBar different height for the tabBar At this point after some research I am able to set the height and background image by subclassing UITabBarController but I'm still not sure on how to accomplish the other items specially the first one related to the nice arrow effect. If someone knows about a very good tutorial on how to do this it would be great for clarifying what can or can't be done by subclassing the UITabBarController and specially if can be done in Interface Builder :) I am just starting on this world off app development for iOS so if you could help me on that it would be really appreciated Thanks a lot in advance

  Read the article

• Group / User based security. Table / SQL question

  - by Brett

  Hi, I'm setting up a group / user based security system. I have 4 tables as follows: user groups group_user_mappings acl where acl is the mapping between an item_id and either a group or a user. The way I've done the acl table, I have 3 columns of note (actually 4th one as an auto-id, but that is irrelevant) col 1 item_id (item to access) col 3 user_id (user that is allowed to access) col 3 group_id (group that is allowed to access) So for example item1, peter, , item2, , group1 item3, jane, , so either the acl will give access to a user or a group. Any one line in the ACL table with either have an item - user mapping, or an item group. If I want to have a query that returns all objects a user has access to, I think I need to have a SQL query with a UNION, because I need 2 separate queries that join like.. item - acl - group - user AND item - acl - user This I guess will work OK. Is this how its normally done? Am I doing this the right way? Seems a little messy. I was thinking I could get around it by creating a single user group for each person, so I only ever deal with groups in my SQL, but this seems a little messy as well..

  Read the article

• Testing ActionFilterAttributes with MSpec

  - by Tomas Lycken

  I'm currently trying to grasp MSpec, mainly to learn new ways of (T/B)DD to be able to make an educated decision on which technology to use. Previously, I've mostly (read: only) used the built-in MSTest framework with Moq, so BDD is quite new for me. I'm writing an ASP.NET MVC app, and I want to implement PRG. Last time I did this, I used action filters to export and import ModelState via TempData, so that I could return a RedirectResult and the validation errors would still be there when the user got the view. I tested that scenario by verifying two things: a) That the ExportModelStateAttribute I had written was applied (among tests for my controller) b) That the attribute worked (among tests for action filter attributes) However, in BDD I've understood I should be even more concerned with behavior, and even less with implementation. This means I should probably just verify that the model state is in tempdata when the action has finished executing - not necessarily that it's done via an attribute. To further complicate things, attributes are not run when calling the action directly in the test, so I can't just call the action and see if the job's been done. How should I spec/test this in MSpec?

  Read the article

• Secure web module for paid subscribtion

  - by DarkJaff

  Hello everyone, I'm building a website (a community web site like digg) but we will soon release a new feature that people will need to pay for. Right now, our website is in pure C# in .NET, very simple pages with some AJAX. When the member log in, there is no HTTPS. Everything is check with session and the internal validation that I do. What we need, is that when the people are logged in, they can click on a link a proceed to a payment (Paypal, credit card, etc). After the payment is done, the "billing module" will return a value to my site to validate that the payment is done so the account will be flagged as "paying member". I'm guessing this is the way to do, maybe I'm wrong! So my questions are: -What is the name of this kind of billing module? (I will do some research on that) -Do you know any ready to go module that does this kind of thing? -(I push my luck) Do you know any FREE module that do this kind of things. If something is not clear, don't hesitate to ask question :) Thanks a lot! DarkJaff

  Read the article

• DotNetNuke and Subversion guidelines

  - by David Stratton

  I've Googled, Binged, and here at StackOverflow, looked through the related questions and searched, but I'm not finding what I'm looking for. I've also searched documentation on DNN. What I'm looking for is any guidance (tutorials, blogs, step-by-step instructions for setting up a repository) etc from people who are experienced in using DotNetNuke with SVN. We use SVN for all our source control, and have no problem with standard applications, because we pretty much built the repository and directory structure to work with our processes. This means when we do web sites, in Visual Studio, we do file based web sites, rather than setting them up in the local IIS. It just makes things easier for us. However, with DNN, it appears that even if you get the source code, it is expecting to be set up in the local IIS, which means additional headaches for us. For example, we are moving all of our source code off our local C drives, and onto a shared drive on a server. This is to enable backups in addition to our normal source control. (This was a management decision). So that means that we need to change the virtual web app when we make the move. Has anyone come up with a good way to work around this? Can DNN be set up so that the developer web server in Visual Studio can be used, so that we can treat it just like any normal web app? Am I missing something obvious? Edit - added I'm willing to accept answers like "We tried it and never got it to work", and "It can't be done" as answers. I'm always open to hearing "It can't be done the way you want. You need to change your procedures to match how it works" if necessary. I guess if you've got experience trying this and just couldn't get it to work, I can learn from your experience that way as well, but some detail would be good.

  Read the article

• How to Store and Retrieve Images Using MsSQL (Server Management Studio)

  - by Joe Majewski

  I am having difficulties when trying to insert files into an MsSQL database. I'll try to break this down as best as I can: What data type should I be using to store image files (jpeg/png/gif/etc)? Right now my table is using the image data type, but I am curious if varbinary would be a better option. How would I go about inserting the image into the database? Does Microsoft SQL Server Management Studio have any built in functions that allow insertions of files into tables? If so, how is that done? Also, how could this be done through the use of an HTML form with PHP handling the input data and placing it into the table? How would I fetch the image from the table and display it on the page? I understand how to SELECT the cell's contents, but how would I go about translating that into a picture. Would I have to have a header(Content type: image/jpeg)? I have no problem doing any of these things with MySQL, but the MsSQL environment is still new to me, and I am working on a project for my job that requires the use of stored procedures to grab various data. Any and all help is appreciated. Thank you very much for your responses!

  Read the article

• Drawbacks with using Class Methods in Objective C.

  - by RickiG

  Hi I was wondering if there are any memory/performance drawbacks, or just drawbacks in general, with using Class Methods like: + (void)myClassMethod:(NSString *)param { // much to be done... } or + (NSArray*)myClassMethod:(NSString *)param { // much to be done... return [NSArray autorelease]; } It is convenient placing a lot of functionality in Class Methods, especially in an environment where I have to deal with memory management(iPhone), but there is usually a catch when something is convenient? An example could be a thought up Web Service that consisted of a lot of classes with very simple functionality. i.e. TomorrowsXMLResults; TodaysXMLResults; YesterdaysXMLResults; MondaysXMLResults; TuesdaysXMLResults; . . . n I collect a ton of these in my Web Service Class and just instantiate the web service class and let methods on this class call Class Methods on the 'Results' Classes. The classes are simple but they handle large amount of Xml, instantiate lots of objects etc. I guess I am asking if Class Methods lives or are treated different on the stack and in memory than messages to instantiated objects? Or are they just instantiated and pulled down again behind the scenes and thus, just a way of saving a few lines of code?

  Read the article

• Alternative to using c:out to prevent XSS

  - by lynxforest

  I'm working on preventing cross site scripting (XSS) in a Java, Spring based, Web application. I have already implemented a servlet filter similar to this example http://greatwebguy.com/programming/java/simple-cross-site-scripting-xss-servlet-filter/ which sanitizes all the input into the application. As an extra security measure I would like to also sanitize all output of the application in all JSPs. I have done some research to see how this could be done and found two complementary options. One of them is the use of Spring's defaultHtmlEscape attribute. This was very easy to implement (a few lines in web.xml), and it works great when your output is going through one of spring's tags (ie: message, or form tags). The other option I have found is to not directly use EL expressions such as ${...} and instead use <c:out value="${...}" /> That second approach works perfectly, however due to the size of the application I am working on (200+ JSP files). It is a very cumbersome task to have to replace all inappropriate uses of EL expressions with the c:out tag. Also it would become a cumbersome task in the future to make sure all developers stick to this convention of using the c:out tag (not to mention, how much more unreadable the code would be). Is there alternative way to escape the output of EL expressions that would require fewer code modifications? Thank you in advance.

  Read the article

• Determining when stringByEvaluatingJavaScriptFromString has finished

  - by alku83

  I have a UIWebView which loads up an HTML page. This page has two buttons on it, say Exit and Submit. I don't want users to be able to click the Exit button, so once the page has finished loading (ie. webViewDidFinishLoad is called), I use stringByEvaluatingJavaScriptFromString to remove one of these buttons, by manipulating the HTML. I also disable user interaction on the UIWebView on webViewDidStartLoad, and enable it again on webViewDidFinishLoad. The problem I am finding is that stringByEvaluatingJavaScriptFromString takes a second or two to complete, and it seems to be done in it's own thread. So what is happening is that webViewDidFinishLoad is called, user interaction is enabled on the UIWebView, and if the user is quick, they can click the Exit button before stringByEvaluatingJavaScriptFromString has finished. As stringByEvaluatingJavaScriptFromString seems to be on it's own thread with no way to know when it's finished (it doesnt call webViewDidFinishLoad), the only way to completely prevent users from tapping the Exit button that I can see is to only enable user interaction on the UIWebView after some delay, which is unreliable (how can I really know how long to delay for?). Am I correct in that stringByEvaluatingJavaScriptFromString is done on it's on thread, and I have no way of being able to tell when it's finished? Any other suggestions for how to get around this problem? EDIT: In short, what I want to know is if it is possible to disable a UIWebView while stringByEvaluatingJavaScriptFromString is executing, and re-enable the UIWebView when the javascript is finished. EDIT 2: There's an article here which seems to imply you can somehow poll the JS engine to see when it's finished, but I can't find any other references saying the same thing: http://drnicwilliams.com/2008/11/10/to-webkit-or-not-to-webkit-within-your-iphone-app/ EDIT 3 Based on the answer from Brad Smith, it seems that I actually need to know when the UIWebView has finished loading itself after the javascript has executed. It's looking more and more like I just need to put a delay of sorts in there.

  Read the article

• Fastest inline-assembly spinlock

  - by sigvardsen

  I'm writing a multithreaded application in c++, where performance is critical. I need to use a lot of locking while copying small structures between threads, for this I have chosen to use spinlocks. I have done some research and speed testing on this and I found that most implementations are roughly equally fast: Microsofts CRITICAL_SECTION, with SpinCount set to 1000, scores about 140 time units Implementing this algorithm with Microsofts InterlockedCompareExchange scores about 95 time units Ive also tried to use some inline assembly with __asm {} using something like this code and it scores about 70 time units, but I am not sure that a proper memory barrier has been created. Edit: The times given here are the time it takes for 2 threads to lock and unlock the spinlock 1,000,000 times. I know this isn't a lot of difference but as a spinlock is a heavily used object, one would think that programmers would have agreed on the fastest possible way to make a spinlock. Googling it leads to many different approaches however. I would think this aforementioned method would be the fastest if implemented using inline assembly and using the instruction CMPXCHG8B instead of comparing 32bit registers. Furthermore memory barriers must be taken into account, this could be done by LOCK CMPXHG8B (I think?), which guarantees "exclusive rights" to the shared memory between cores. At last [some suggests] that for busy waits should be accompanied by NOP:REP that would enable Hyper-threading processors to switch to another thread, but I am not sure whether this is true or not? From my performance-test of different spinlocks, it is seen that there is not much difference, but for purely academic purpose I would like to know which one is fastest. However as I have extremely limited experience in the assembly-language and with memory barriers, I would be happy if someone could write the assembly code for the last example I provided with LOCK CMPXCHG8B and proper memory barriers in the following template: __asm { spin_lock: ;locking code. spin_unlock: ;unlocking code. }

  Read the article

< Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >