Search Results

Search found 1838 results on 74 pages for 'miss spider'.

Page 63/74 | < Previous Page | 59 60 61 62 63 64 65 66 67 68 69 70  | Next Page >

• Have I taken a wrong path in programming by being excessively worried about code elegance and style?

  - by Ygam

  I am in a major stump right now. I am a BSIT graduate, but I only started actual programming less than a year ago. I observed that I have the following attitude in programming: I tend to be more of a purist, scorning unelegant approaches to solving problems using code I tend to look at anything in a large scale, planning everything before I start coding, either in simple flowcharts or complex UML charts I have a really strong impulse on refactoring my code, even if I miss deadlines or prolong development times I am obsessed with good directory structures, file naming conventions, class, method, and variable naming conventions I tend to always want to study something new, even, as I said, at the cost of missing deadlines I tend to see software development as something to engineer, to architect; that is, seeing how things relate to each other and how blocks of code can interact (I am a huge fan of loose coupling) i.e the OOP thinking I tend to combine OOP and procedural coding whenever I see fit I want my code to execute fast (thus the elegant approaches and refactoring) This bothers me because I see my colleagues doing much better the other way around (aside from the fact that they started programming since our first year in college). By the other way around I mean, they fire up coding, gets the job done much faster because they don't have to really look at how clean their codes are or how elegant their algorithms are, they don't bother with OOP however big their projects are, they mostly use web APIs, piece them together and voila! Working code! CLients are happy, they get paid fast, at the expense of a really unmaintainable or hard-to-read code that lacks structure and conventions, or slow executions of certain actions (which the common reasoning against would be that internet connections are much faster these days, hardware is more powerful). The excuse I often receive is clients don't care about how you write the code, but they do care about how long you deliver it. If it works then all is good. Now, did my "purist" approach to programming may have been the wrong way to start programming? Should I just dump these purist concepts and just code the hell up because I have seen it: clients don't really care how beautifully coded it is?

  Read the article

• SQL Server database change workflow best practices

  - by kubi

  The Background My group has 4 SQL Server Databases: Production UAT Test Dev I work in the Dev environment. When the time comes to promote the objects I've been working on (tables, views, functions, stored procs) I make a request of my manager, who promotes to Test. After testing, she submits a request to an Admin who promotes to UAT. After successful user testing, the same Admin promotes to Production. The Problem The entire process is awkward for a few reasons. Each person must manually track their changes. If I update, add, remove any objects I need to track them so that my promotion request contains everything I've done. In theory, if I miss something testing or UAT should catch it, but this isn't certain and it's a waste of the tester's time, anyway. Lots of changes I make are iterative and done in a GUI, which means there's no record of what changes I made, only the end result (at least as far as I know). We're in the fairly early stages of building out a data mart, so the majority of the changes made, at least count-wise, are minor things: changing the data type for a column, altering the names of tables as we crystallize what they'll be used for, tweaking functions and stored procs, etc. The Question People have been doing this kind of work for decades, so I imagine there have got to be a much better way to manage the process. What I would love is if I could run a diff between two databases to see how the structure was different, use that diff to generate a change script, use that change script as my promotion request. Is this possible? If not, are there any other ways to organize this process? For the record, we're a 100% Microsoft shop, just now updating everything to SQL Server 2008, so any tools available in that package would be fair game.

  Read the article

• How do I write a J2EE/EJB Singleton?

  - by Bears will eat you

  A day ago my application was one EAR, containing one WAR, one EJB JAR, and a couple of utility JAR files. I had a POJO singleton class in one of those utility files, it worked, and all was well with the world: EAR |--- WAR |--- EJB JAR |--- Util 1 JAR |--- Util 2 JAR |--- etc. Then I created a second WAR and found out (the hard way) that each WAR has its own ClassLoader, so each WAR sees a different singleton, and things break down from there. This is not so good. EAR |--- WAR 1 |--- WAR 2 |--- EJB JAR |--- Util 1 JAR |--- Util 2 JAR |--- etc. So, I'm looking for a way to create a Java singleton object that will work across WARs (across ClassLoaders?). The @Singleton EJB annotation seemed pretty promising until I found that JBoss 5.1 doesn't seem to support that annotation (which was added as part of EJB 3.1). Did I miss something - can I use @Singleton with JBoss 5.1? Upgrading to JBoss AS 6 is not an option right now. Alternately, I'd be just as happy to not have to use EJB to implement my singleton. What else can I do to solve this problem? Basically, I need a semi-application-wide* hook into a whole bunch of other objects, like various cached data, and app config info. As a last resort, I've already considered merging my two WARs into one, but that would be pretty hellish. *Meaning: available basically anywhere above a certain layer; for now, mostly in my WARs - the View and Controller (in a loose sense).

  Read the article

• Oracle Date Format Convert Hour-Minute to Interval and Disregard Year-Month-Day

  - by dlite922

  I need to compare an event's half-way midpoint between a start and stop time of day. Right now i'm converting the dates you see on the right, to HH:MM and the comparison works until midnight. the query says: WHERE half BETWEEN pStart and pStop. As you can see below, pStart and pStap have January 1st 2000 dates, this is because the year month day are not important to me... Valid Data: +-------+--------+-------+---------------------+---------------------+---------------------+ | half | pStart | pStop | half2 | pStart2 | pStop2 | +-------+--------+-------+---------------------+---------------------+---------------------+ | 19:00 | 19:00 | 23:00 | 2012-11-04 19:00:00 | 2000-01-01 19:00:00 | 2000-01-01 23:00:00 | | 20:00 | 19:00 | 23:00 | 2012-11-04 20:00:00 | 2000-01-01 19:00:00 | 2000-01-01 23:00:00 | | 21:00 | 19:00 | 23:00 | 2012-11-04 21:00:00 | 2000-01-01 19:00:00 | 2000-01-01 23:00:00 | | 23:00 | 20:00 | 23:00 | 2012-11-05 23:00:00 | 2000-01-01 20:00:00 | 2000-01-01 23:00:00 | +-------+--------+-------+---------------------+---------------------+---------------------+ Now observe what happens when pStop is midnight or later... Valid Data that breaks it: +-------+--------+-------+---------------------+---------------------+---------------------+ | half | pStart | pStop | half2 | pStart2 | pStop2 | +-------+--------+-------+---------------------+---------------------+---------------------+ | 23:00 | 22:00 | 00:00 | 2012-11-04 23:00:00 | 2000-01-01 22:00:00 | 2000-01-01 00:00:00 | | 23:30 | 23:00 | 02:00 | 2012-11-05 23:30:00 | 2000-01-01 23:00:00 | 2000-01-01 02:00:00 | +-------+--------+-------+---------------------+---------------------+---------------------+ Thus my where clause translates to: WHERE 19:00 BETWEEN 22:00 AND 00:00 ...which returns false and I miss those two correct rows above. Question: Is there a way to show those dates as integer interval so that saying half BETWEEN pStart and pStop are correct? I thought about adding 24 when pStop is less than pStart to make 00:00 into 24:00 but don't know an easy way to do that without long string concatenations and number conversions. This would solve the problem because pStart pStop difference will never be longer than 6 hours. Note: (The Query is much more complex. It has other irrelevant date calculations, but the result are show above. DATE_FORMAT(%H:%i) is applied to the first three columns and no formatting to the last three) Thanks for your help:

  Read the article

• Jquery animate bottom problem

  - by andrea

  It's strange. I have an animation that start when i .hover on a DIV. Into this div i have another in position absolute that i want to move up until the mouse stay on main div and go down in your position when i go out of main div. A simple hover effect. I have write down this function that work well apart a strange bug. var inside = $('.inside') inside.hover(function() { $(this).children(".coll_base").stop().animate({ bottom:'+=30px' },"slow") }, function() { $(this).children(".coll_base").stop().animate({ bottom:'-=30px' },"slow"); }); i need +=30 and -=30 because i have to apply this function to a range of div with different bottom. The problem is that if i hover on and out of div the DIV animate right but when go down he decrease the value of bottom every animation. If i go up and down from the main div i see that the animated div go down even beyond the main div. I think that i miss something to resolve this bug. Thanks for any help

  Read the article

• PHP DOMDocument Error Handling Problem

  - by Jon

  I'm having trouble trying to write an if statement for DOM that will check if $html is blank. However whenever the html page does end up blank, it just removes everything that would be below DOM (including what I had to check if it was blank). $html = file_get_contents("http://example.com/"); $dom = new DOMDocument; @$dom->loadHTML($html); $links = $dom->getElementById('dividhere')->getElementsByTagName('img'); foreach ($links as $link) { echo $link->getAttribute('src'); } All this does is grab an image url in the specified div, which works perfectly until the page is a blank html page. I've tried using SimpleHTMLDOM, which didn't work either (it didn't even fetch the image on working pages). Did I happen to miss something with this one or am I just missing something in both? include_once('simple_html_dom.php') $html = file_get_html("http://example.com/"); foreach($html->find('div[id="dividhere"]') as $div) { if(empty($div->src)) { continue; } echo $div->src; }

  Read the article

• Yet another Haskell vs. Scala question

  - by Travis Brown

  I've been using Haskell for several months, and I love it—it's gradually become my tool of choice for everything from one-off file renaming scripts to larger XML processing programs. I'm definitely still a beginner, but I'm starting to feel comfortable with the language and the basics of the theory behind it. I'm a lowly graduate student in the humanities, so I'm not under a lot of institutional or administrative pressure to use specific tools for my work. It would be convenient for me in many ways, however, to switch to Scala (or Clojure). Most of the NLP and machine learning libraries that I work with on a daily basis (and that I've written in the past) are Java-based, and the primary project I'm working for uses a Java application server. I've been mostly disappointed by my initial interactions with Scala. Many aspects of the syntax (partial application, for example) still feel clunky to me compared to Haskell, and I miss libraries like Parsec and HXT and QuickCheck. I'm familiar with the advantages of the JVM platform, so practical questions like this one don't really help me. What I'm looking for is a motivational argument for moving to Scala. What does it do (that Haskell doesn't) that's really cool? What makes it fun or challenging or life-changing? Why should I get excited about writing it?

  Read the article

• Java many to many association map

  - by Raphael Jolivet

  Hi, I have to classes, ClassA and ClassB and a "many to many" AssociationClass. I want to use a structure to hold the associations between A and B such as I can know, for each instance of A or B, which are their counterparts. I thought of using a Hashmap, with pair keys: Hasmap<Pair<ClassA, ClassB>, AssociationClass> associations; This way, I can add and remove an association between two instances of ClassA and ClassB, and I can query a relation for two given instances. However, I miss the feature of getting all associations defined for a given instance of ClassA or ClassB. I could do it by brute force and loop over all keys of the map to search for associations between a given instance, but this is inefficient and not elegant. Do you know of any data structure / free library that enables this ? I don't want to reinvent the wheel. Thanks in advance for your help, Raphael NB: This is not a "database" question. These objects are pure POJO used for live computation, I don't need persistence stuff.

  Read the article

• Hidden div height

  - by fudgey

  Ok, I was going to answer someone's question here on SO about why their script wasn't working. They loaded content into a hidden div, then got the height so they could animate the wrapping div. But I always try to test the code I provide. So I made this demo to prove it to them. So, umm, have I entered the twilight zone or am I dreaming right now? pinches self OUCH! I tried that demo in Firefox, IE and Chrome and both methods return the same value. Firebug says zero! I rebooted my computer and I even changed the code a bit (removed the height function) and tried it with jQuery 1.3.2 and it still worked! I know hidden elements USED to return a zero value. Even this SO Answer is giving the advice I would have! So I guess my question is... did I miss something or are we giving bad advice?

  Read the article

• Hiring my first employee

  - by Ady

  A few years ago I moved to a new job having been programming for 2 years using C#, however this new company was mainly using VB6. I made the case for .NET and won, but one of the consessions I had to make was to use VB.NET and not C# (understandable as most of the other developers were already using VB). Three years later it was time to move on, but when applying for jobs I couldn't get past the recruitment agents. I realised that when they were looking at the basic requirements (5 years experience) that they could not add 2 and 3 together to make 5. They were looking for 5 years in VB or C# not across both. Frustrated I decided to combine my skills with a designer friend and start my own company. After two years of hard graft we are now looking for our first employee (a programmer), and this question has hit me again, but now I see the employers perspective. Why take the risk of someone getting up to speed when you have thousands of applicants to choose from. So my question is this, if I define the requirements to be too narrow, I could miss the really great candidates. But if they are too broad it's going to take ages to go through them all. This will be our first 'employee' so the choice needs to be good, I can't afford to make a mistake and employ someone naff. Another option would be to choose a bright university graduate, and train them up (less of a risk because we can pay them less). What have others done in this situation, and what would you recommend I do?

  Read the article

• Monotouch threads, GC, WCF

  - by cvista

  Hi This is a question about best practices i guess but it applies directly to my current MT project. I'm using WCF services to communicate with the server. To do this i do the following: services.MethodToCall(params); and the asynch: services.OnMethodToCallCompleted += delegate{ //do stuff and ting }; This can lead to issues if you're not careful in that variables defined within the scope of the asynch callback can sometimes be cleaned up by the gc and this can cause crashes. So - I am making it a practice to declare these outside of the scope of the callback unless I am 100% sure they are not needed. Now - when doing stuff and ting implies changing the ui - i wrap it all in an InvokeOnMainThread call. I guess wrapping everything in this would slow the main thread down and rubbish the point of having multi threads. Even though I'm being careful about all this i am still getting crashes and I have no idea why! I am certain it has something to do with threads, scope and all that. Now - the only thing I can think of outside of updating the UI that may need to happen inside of InvokeOnMainThread is that I have a singleton 'Database' class. This is based on the version 5 code from this thread http://www.yoda.arachsys.com/csharp/singleton.html So now if the service method returns data that needs to be added/updated to the Database class -I also wrap this inside an InvokeOnMainThread call. Still getting random crashes. So... My question is this: I am new to thick client dev - I'm coming from a web dev perspective where we don't need to worry about threads so much :) Aside from what I have mentioned -are there any other things I should be aware of? Is the above stuff correct? Or am i miss-understanding something? Cheers w://

  Read the article

• MySQL Normalization stored procedure performance

  - by srkiNZ84

  Hi, I've written a stored procedure in MySQL to take values currently in a table and to "Normalize" them. This means that for each value passed to the stored procedure, it checks whether the value is already in the table. If it is, then it stores the id of that row in a variable. If the value is not in the table, it stores the newly inserted value's id. The stored procedure then takes the id's and inserts them into a table which is equivalent to the original de-normailized table, but this table is fully normalized and consists of mainly foreign keys. My problem with this design is that the stored procedure takes approximately 10ms or so to return, which is too long when you're trying to work through some 10million records. My suspicion is that the performance is to do with the way in which I'm doing the inserts. i.e. INSERT INTO TableA (first_value) VALUES (argument_from_sp) ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id); SET @TableAId = LAST_INSERT_ID(); The "ON DUPLICATE KEY UPDATE" is a bit of a hack, due to the fact that on a duplicate key I don't want to update anything but rather just return the id value of the row. If you miss this step though, the LAST_INSERT_ID() function returns the wrong value when you're trying to run the "SET ..." statement. Does anyone know of a better way to do this in MySQL? Thank you

  Read the article

• Where did Pylons beautiful error handling go? Using Nginx + Paster + Flup#fcgi_thread

  - by Tony

  I need to run my development through nginx due to some complicated subdomain routing rules in my pylons app that wouldn't be handled otherwise. I had been using lighttpd + paster + Flup#scgi_thread and the nice error reporting by Pylons had been working fine in that environment. Yesterday I recompiled Python and MySQL for 64bit, and also switched to Ngix + paster + Flup#fcgi_thread for my development environment. Everything is working great, but I miss the fancy error reports. This is what I get now, and it is a mess compared to what I got used to: http://drp.ly/Iygeg . And here are the pylons/nginx configs. Pylons: [server:main] use = egg:Flup#fcgi_thread host = 0.0.0.0 port = 6500 Nginx: location / { #include /usr/local/nginx/conf/fastcgi.conf; fastcgi_param PATH_INFO $fastcgi_script_name; fastcgi_param REQUEST_METHOD $request_method; fastcgi_param QUERY_STRING $query_string; fastcgi_param CONTENT_TYPE $content_type; fastcgi_param CONTENT_LENGTH $content_length; fastcgi_param SERVER_ADDR $server_addr; fastcgi_param SERVER_PORT $server_port; fastcgi_param SERVER_NAME $server_name; fastcgi_param SERVER_PROTOCOL $server_protocol; fastcgi_param REMOTE_ADDR $remote_addr; fastcgi_pass_header Authorization; fastcgi_intercept_errors off; fastcgi_pass 127.0.0.1:6500; }

  Read the article

• Old fashioned html onclick return false doesnt in IE work when jquery script included

  - by user292662

  Ok, so im quite new to jquery but found this bizzar problem just now, If we ignore jquery for a second and consider this scenario, if i have two links like below both with an href and both with and onclick event. The first link will not follow the href because the onclick returns false, and the second link will because the onclick returns true. <a href="/page.html" onclick="return false;">Dont follow</a> <a href="/page.html" onclick="return false;">Follow</a> This works just hunky dory in every browser as it should, the thing is, as soon as i include the jQuery script on the page this stops working in all versions of IE which then always follows the href whether the onclick returns false or not. (it continues to work fine in other browsers) Now if i add an event using jquery and call .preventDefault() on the event object instead of doing it the old fashioned way this behaves correctly, and you may say, well just do that then? But i have a site with thousands of lines of code and i am adding jquery support, i dont want to run the risk that i might miss an already defined html onclick="" and break the website. I cant see why jQuery should prevent perfectly normal javascript concepts from working, so is this a jQuery bug or am I missing something?

  Read the article

• Which parts of the client certificate to use when uniquely identifying users?

  - by miha

  I'm designing a system where users will be able to register and afterward authenticate with client certificates in addition to username/password authentication. The client certificates will have to be valid certificates issued by a configured list of certificate authorities and will be checked (validated) when presented. In the registration phase, I need to store part(s) of the client certificate in a user repository (DB, LDAP, whatever) so that I can map the user who authenticates with client certificate to an internal "user". One fairly obvious choice would be to use certificate fingerprint; But fingerprint itself is not enough, since collisions may occur (even though they're not probable), so we need to store additional information from the certificate. This SO question is also informative in this regard. RFC 2459 defines (4.1.2.2) that certificate serial number must be unique within a given CA. With all of this combined, I'm thinking of storing certificate serial number and certificate issuer for each registered user. Given that client certificates will be verified and valid, this should uniquely identify each client certificate. That way, even when client certificate is renewed, it would still be valid (serial number stays the same, and so does the issuer). Did I miss something?

  Read the article

• problem with evolutionary algorithms degrading into simulated annealing: mutation too small?

  - by Schnalle

  i have a problem understanding evolutionary algorithms. i tried using this technique several times, but i always ran into the same problem: degeneration into simulated annealing. lets say my initial population, with fitness in brackets, is: A (7), B (9), C (14), D (19) after mating and mutation i have following children: AB (8.3), AC (12.2), AD (14.1), BC(11), BD (14.7), CD (17) after elimination of the weakest, we get A, AB, B, AC next turn, AB will mate again with a result around 8, pushing AC out. next turn, AB again, pushing B out (assuming mutation changes fitness mostly in the 1 range). now, after only a few turns the pool is populated with the originally fittest candidates (A, B) and mutations of those two (AB). this happens regardless of the size of the initial pool, it just takes a bit longer. say, with an initial population of 50 it takes 50 turns, then all others are eliminated, turning the whole setup in a more complicated simulated annealing. in the beginning i also mated canditates with themselves, worsening the problem. so, what do i miss? are my mutation rates simply too small and will it go away if i increase them? here's the project i'm using it for: http://stefan.schallerl.com/simuan-grid-grad/ yeah, the code is buggy and the interface sucks, but i'm too lazy to fix it right now - and be careful, it may lock up your browser. better use chrome, even thought firefox is not slower than chrome for once (probably the tracing for the image comparison pays off, yay!). if anyone is interested, the code can be found here. here i just dropped the ev-alg idea and went for simulated annealing. ps: i'm not even sure about simulated annealing - it is like evolutionary algorithms, just with a population size of one, right?

  Read the article

• The Immerman-Szelepcsenyi Theorem

  - by Daniel Lorch

  In the Immerman-Szelepcsenyi Theorem, two algorithms are specified that use non-determinisim. There is a rather lengthy algorithm using "inductive counting", which determines the number of reachable configurations for a given non-deterministic turing machine. The algorithm looks like this: Let m_{i+1}=0 For all configurations C Let b=0, r=0 For all configurations D Guess a path from I to D in at most i steps If found Let r=r+1 If D=C or D goes to C in 1 step Let b=1 If r<m_i halt and reject Let m_{i+1}=m_{i+1}+b I is the starting configuration. m_i is the number of configurations reachable from the starting configuration in i steps. This algorithm only calculates the "next step", i.e. m_i+1 from m_i. This seems pretty reasonable, but since we have nondeterminisim, why don't we just write: Let m_i = 0 For all configurations C Guess a path from I to C in at most i steps If found m_i = m_i + 1 What is wrong with this algorithm? I am using nondeterminism to guess a path from I to C, and I verify reachability I am iterating through the list of ALL configurations, so I am sure to not miss any configuration I respect space bounds I can generate a certificate (the list of reachable configs) I believe I have a misunderstanding of the "power" of non-determinisim, but I can't figure out where to look next. I am stuck on this for quite a while and I would really appreciate any help.

  Read the article

• sorting a timer in matlab

  - by AP

  ok it seems like a simple problem, but i am having problem I have a timer for each data set which resets improperly and as a result my timing gets mixed. Any ideas to correct it? without losing any data. Example timer col ideally should be timer , mine reads 1 3 2 4 3 5 4 6 5 1 6 2 how do i change the colum 2 or make a new colum which reads like colum 1 without changing the order of ther rows which have data this is just a example as my file lengths are 86000 long , also i have missing timers which i do not want to miss , this imples no data for that period of time. thanks EDIT: I do not want to change the other columns. The coulm 1 is the gps counter and so it does not sync with the comp timer due to some other issues. I just want to change the row one such that it goes from high to low without effecting other rows. also take care of missing pts ( if i did not care for missing pts simple n=1: max would work.

  Read the article

• can javascript process binary data?

  - by Johnny

  admit me describe my questions in situation-oriented way: assume IE is still the dominate web browser(the firefox have document for binary processing): the XMLHttpRequest.responseText or XMLHttpRequest.responseXML in ie desire txt or xml/xhtml/html,but what about the server response the xmlHttprequest whith MIME TYPE application/octet ? would the response string all little than 256 ?(every char of that string < 256), thanks very much for a straight answer, i have no webserver env,so i don't know how to test it out. because use txt or xml have a issue of character set encode, and i don't know how to process #[[[CDDATA node of one encoded xml(ex : utf-8,ascii,gb18030) with javascript, when i getNodeText, does the docObj return me byte or decoded char ? if it was decoded char which according to the header indicated charSet in the httpresponse , it would be all wrong. to avoid mess up with charSet ,i would like the server to response octet data and force strings data to be encoded as utf-8 but another charSet in the binary format. if the response is octal, so i guess the browser would not try to decode the response"txt" does this weird? or miss understanding the fundamental things? EDIT: I believe the question is asking this: Can Javascript safely process strings that aren't encoded in Unicode? What are the problems with trying to do so? EDIT: no no no , i means if http-header: content-type is "application/octet" , would the ie try to decoded it as (16bits Unicode | ie local setting charset ) when i get XMLHttpRequestobj.responseText use javascript ? or it(ie) just wrap every single byte of the response body as a javascript string, then every char in that string little than or equal 256 (char<=256), am i talking Mars language? sadly, if i were Marsizen,i would come as tourist without fuzzy questions. however i am in a country which share at least one property with Mars : RED

  Read the article

• How do I run a universal app on the iPhone 3.1.3 simulator?

  - by bpapa

  I'm working on a new app that I want to be universal for the iPhone and iPad. I started out with the "Create a Window-based app" wizard, and it created separate app delegates in "iPhone" and "iPad" groups. Since I already was quite familiar with iPhone dev, I did that part of my project, and now I'm ready to do some iPad stuff. So... I started out by adding a UISplitViewController to my iPad delegate, switch the Active SDK to 3.2, and it works! But when I switch back to 3.1.3, and try to run it in the simulator, Build and Go fails. For starters, I see: ...path.../iPad/AppDelegate_Pad.h:13: error: expected specifier-qualifier-list before 'UISplitViewController' I've got my Base SDK set to 3.2 and my Deployment Target set to 3.1.3. I thought that was enough. But I also have found in the documentation this method to conditionally compile: #if __IPHONE_OS_VERSION_MAX_ALLOWED >= 30200 MyIPadViewController* vc; // Create the iPad view controller #else MyIPhoneViewController* vc; // Create the iPhone view controller #endif So do I need to do this everywhere? It seems like an awful lot of code to add (that I'll be getting rid of in a short time for 4.0 anyway) so I feel like I must be doing something wrong. And, I don't even have any idea how this works for things like @property or @synthesize declarations. tl;dr version of the question - did I miss a setting somewhere?

  Read the article

• Passing Derived Class Instances as void* to Generic Callbacks in C++

  - by Matthew Iselin

  This is a bit of an involved problem, so I'll do the best I can to explain what's going on. If I miss something, please tell me so I can clarify. We have a callback system where on one side a module or application provides a "Service" and clients can perform actions with this Service (A very rudimentary IPC, basically). For future reference let's say we have some definitions like so: typedef int (*callback)(void*); // This is NOT in our code, but makes explaining easier. installCallback(string serviceName, callback cb); // Really handled by a proper management system sendMessage(string serviceName, void* arg); // arg = value to pass to callback This works fine for basic types such as structs or builtins. We have an MI structure a bit like this: Device <- Disk <- MyDiskProvider class Disk : public virtual Device class MyDiskProvider : public Disk The provider may be anything from a hardware driver to a bit of glue that handles disk images. The point is that classes inherit Disk. We have a "service" which is to be notified of all new Disks in the system, and this is where things unravel: void diskHandler(void *p) { Disk *pDisk = reinterpret_cast<Disk*>(p); // Uh oh! // Remainder is not important } SomeDiskProvider::initialise() { // Probe hardware, whatever... // Tell the disk system we're here! sendMessage("disk-handler", reinterpret_cast<void*>(this)); // Uh oh! } The problem is, SomeDiskProvider inherits Disk, but the callback handler can't receive that type (as the callback function pointer must be generic). Could RTTI and templates help here? Any suggestions would be greatly appreciated.

  Read the article

• UIImagePickerController random behavior

  - by pion

  I have the following code snippets: @interface PinRecordNewTableViewController : UITableViewController { } ... @implementation PinRecordNewTableViewController ... - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { ... PinRecordNewPicture *pinRecordNewPicture = [[PinRecordNewPicture alloc] initWithNibName:@"PinRecordNewPicture" bundle:nil]; pinRecordNewPicture.delegate = self; [self.navigationController pushViewController:pinRecordNewPicture animated:YES]; [pinRecordNewPicture release]; ... } @interface PinRecordNewPicture : UIViewController ... @implementation PinRecordNewPicture ... - (void)picturePicker:(UIImagePickerControllerSourceType)theSource { UIImagePickerController *picker = [[UIImagePickerController alloc] init]; picker.delegate = self; picker.sourceType = theSource; picker.allowsEditing = YES; [self presentModalViewController:picker animated:YES]; [picker release]; } - (IBAction) takePicture:(id)sender { UIImagePickerControllerSourceType source = UIImagePickerControllerSourceTypeCamera; if ([UIImagePickerController isSourceTypeAvailable:source]) { [self picturePicker:source]; } It works 80% of the time -- I could get the picture correctly. The problem is that it occasionally failed to take a picture. When tracing the code, I found out that it occasionally goes to -PinRecordNewTableViewController:viewDidUnload. This is where it fails because it set nil to all ivars. What did I do wrong? Did I miss something so it behaves "randomly"? Thanks in advance for your help.

  Read the article

• Proper way to scan a range of IP addresses

  - by Josh G

  Given a range of IP addresses entered by a user (through various means), I want to identify which of these machines have software running that I can talk to. Here's the basic process: Ping these addresses to find available machines Connect to a known socket on the available machines Send a message to the successfully established sockets Compare the response to the expected response Steps 2-4 are straight forward for me. What is the best way to implement the first step in .NET? I'm looking at the System.Net.NetworkInformation.Ping class. Should I ping multiple addresses simultaneously to speed up the process? If I ping one address at a time with a long timeout it could take forever. But with a small timeout, I may miss some machines that are available. Sometimes pings appear to be failing even when I know that the address points to an active machine. Do I need to ping twice in the event of the request getting discarded? To top it all off, when I scan large collections of addresses with the network cable unplugged, Ping throws a NullReferenceException in FreeUnmanagedResources(). !? Any pointers on the best approach to scanning a range of IPs like this?

  Read the article

• gdb: Cannot find new threads: generic error

  - by Alexander Gladysh

  When I run GDB against a program which loads a .so which is linked to pthreads, GDB reports error "Cannot find new threads: generic error". I probably miss something in my Ubuntu configuration (as it was installed from minimal install). Any clues? $ gdb --args lua -lluarocks.require GNU gdb (GDB) 7.0-ubuntu Copyright (C) 2009 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-linux-gnu". For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>... Reading symbols from /usr/bin/lua...(no debugging symbols found)...done. (gdb) run Starting program: /usr/bin/lua -lluarocks.require Lua 5.1.4 Copyright (C) 1994-2008 Lua.org, PUC-Rio require 'ev' [Thread debugging using libthread_db enabled] Cannot find new threads: generic error (gdb) q A debugging session is active. Inferior 1 [process 4986] will be killed. Quit anyway? (y or n) y This function gets called on require 'ev': http://github.com/brimworks/lua-ev/blob/master/lua_ev.c#L25-65 Additional information about my system: $ uname -a Linux localhost 2.6.31-20-generic #58-Ubuntu SMP Fri Mar 12 04:38:19 UTC 2010 x86_64 GNU/Linux $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 9.10 Release: 9.10 Codename: karmic

  Read the article

• Terminate function on System.in .. possible?

  - by Ronald

  I am currently working on a project where I have to make an agent to interact with a server. Each 50ms, the server will receive the last thing I outputted to System.out and send me a new set of lines as a 'state' through the System.in printstream to analyze and send my next message to System.out. Also, if the server receives multiple outputs from me, it only regards the most recent one. .. As for my question: My program originally constructed a tree and then analyzed each leaf node to see which would be optimal, and then waited around for the next input, but I can recursively do a deeper tree search that would make my output 'better' (and again and again to keep returning a better result). Using this and the fact that if the server receives multiple outputs, it only takes the most recent one, I could do each level, print my result and start the next level. But here comes my problem... I can't be stuck in some complex algorithm while I am supposed to receiving the next input as I will then miss it. So I was wondering if there is a way to cancel anything else I am doing when I receive something via System.in and then go back to the beginning of the function and start the search again with the new set of input (and rinse and repeat..) I hope this all makes sense, Thank ye all

  Read the article

< Previous Page | 59 60 61 62 63 64 65 66 67 68 69 70  | Next Page >