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  • Can't resignFirstResponder with UITextView

    - by Calvin L
    I have a UITextView. I implemented a navigationBar UIBarButtonItem to respond to a touch and resign the firstResponder for my UITextView. But, when the selector method is called, the keyboard doesn't get dismissed. I checked the UITextView's responder status with isFirstResponder and it returns YES. I also checked it with canResignFirstResponder and the return value is NO. I must be missing something here...why is it returning NO? I get that I can override canResignFirstResponder by subclassing UITextView, but I'd like to avoid that if possible. Here's a code snippet: - (void) commentCancelButtonTouched:(id)sender { NSLog(@"Cancel button touched"); [self.navigationBar popNavigationItemAnimated: NO]; if ([self.textInput.textView canResignFirstResponder] == NO) { NSLog(@"I don't want to resign!"); } [self.textInput.textView resignFirstResponder]; }

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  • Launching Vim via Lua

    - by Keith Pimmel
    I'm writing a simple little Lua commandline app that will build a static website. I'm storing my fragments in a sqlite database. Retrieving the data from the db is straightforward as is saving it; my question comes from editing the data. Is there an elegant way to pipe the data from Lua to vim? Can vim edit a memory buffer and return it? I was planning on launching the editor via os.execute('vim') but only after grabbing a temporary file handle and dumping the database output into that. I would like to have to avoid touching the filesystem that way but that is my contingency plan.

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  • Bitbanging a PIO on Coldfire/ucLinux

    - by G Forty
    Here's the problem: I need to program some hardware via 2 pins of the PIO (1 clock, 1 data). Timing constraints are tight - 10ms clock cycle time. All this, of course, whilst I maintain very high level services (CAN bus, TCP/IP). The downstream unit also ACKS by asserting a PIO pin, configured as an input, high. So this loop has to both read and write. I need to send 16 bits in the serial stream. Is there an established way to do this sort of thing or should I simply get the hardware guys to add a PIC or somesuch. I'd much prefer to avoid exotics like RTAI extensions at this stage. I did once see a reference to user-mode IO which implied a possible interrupt driven driver but lost track of it. Any pointers welcomed.

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  • Python UTF-16 encoding hex representation

    - by Romeno
    I have a string in Python 2.7.2 say u"\u0638". When I write it to file: f = open("J:\\111.txt", "w+") f.write(u"\u0638".encode('utf-16')) f.close() In hex it looks like: FF FE 38 06 When i print such a string to stdout i will see: '\xff\xfe8\x06'. The querstion: Where is \x38 in the string output to stdout? In other words why the string output to stdout is not '\xff\xfe\x38\x06'? If I write the string to file twice: f = open("J:\\111.txt", "w+") f.write(u"\u0638".encode('utf-16')) f.write(u"\u0638".encode('utf-16')) f.close() The hex representation in file contains byte order mark (BOM) \xff\xfe twice: FF FE 38 06 FF FE 38 06 I wonder what is the techique to avoid writting BOM in UTF-16 encoded strings?

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  • PHPMailer safe practices - Send escaped / sanitized variables or not ?

    - by FreekOne
    I'm using the PHPMailer-Lite class to build an email sending script and I'm not sure if I should use addslashses() on the $name variable when adding it to the constructor. If somebody's last name would be O'Riley (or any other name that contains characters which should normally be sanitized before handling) and I would send it unescaped, wouldn't it mess with the script/email sending ? Is it safe to send it unescaped ? As a side note, I would also like to avoid having my message body say "Hello, O\'Riley". Looking at the source, I saw that it only trims the whitespace and line ending (\r\n) characters from the received $name variable, so any advice on this would be more than welcome. Thank you all in advance !

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  • How do I adjust overall width of rdlc report when some columns are hidden?

    - by user115487
    I have a customizable rdlc report where the user can choose which columns to show. All the columns are included in the report designer, and I use parameters to hide/show columns based on the user's choice. The report renders correctly, and only shows the selected columns, HOWEVER, the overall width of the report is the same as if all the columns were visible. This means that the report can have a huge empty area to the right of the selected columns, which looks very silly. So my question: Is there a way to adjust the report width dynamically at runtime to avoid a large silly empty area in the report? I attempted to do this in the designer by assigning a parameter to the width of the report body....but that was not allowed. The width cannot be an expression of any kind in the designer, only an actual value is allowed. Any suggestions?

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  • Spring MVC; avoiding file extension in url?

    - by Ezombort
    I just started with Spring Web MVC. I'm trying to avoid file extenstions in the url. How can i do this? (I'm using Spring 2.5.x) Bean: <bean name="/hello.htm" class="springapp.web.HelloController"/> I want it to be: <bean name="/hello" class="springapp.web.HelloController"/> I cannot get it to work. Any ideas? Edit: Url-mapping <servlet-mapping> <servlet-name>springapp</servlet-name> <url-pattern>*.htm</url-pattern> </servlet-mapping> I have tried changing the url-pattern with no luck (* and /*).

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  • Is Stopwatch really broken?

    - by Jakub Šturc
    At MSDN page for Stopwatch class I discovered link to interesting article which makes following statement about Stopwatch: However there are some serious issues: This can be unreliable on a PC with multiple processors. Due to a bug in the BIOS, Start() and Stop() must be executed on the same processor to get a correct result. This is unreliable on processors that do not have a constant clock speed (most processors can reduce the clock speed to conserve energy). This is explained in detail here. I am little confused. I've seen tons of examples of using Stopwatch and nobody mention this drawbacks. How serious is this? Should I avoid using Stopwatch?

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  • Model Binding an IList of selected items only

    - by jeef3
    I have an action method setup: public ActionResult Delete(IList<Product> products) And a table of products in my view. I have got Model Binding working so that on submit I can populate the products list. But I would like to populate it with only the products that are selected via a checkbox. I think I could do it by changing the action method to this: public ActionResult Delete(IList<Product> products, IList<int> toDelete) And passing the list of check boxes to the toDelete but I would really like to avoid changing the method signature if possible. Is there a way to pass only the selected items? Or am I going to have to write a custom ModelBinder?

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  • Jquery - effect + autohide

    - by lidermin
    Hello, I'm using jquery to animate a bit my web site, but I'm having a little issue with some behaviour: I have a div, which suddenly appears from the top of the page and shakes: $(minipopup).animate({ marginTop: '+=' + (240) + 'px' }, 1000); $(minipopup).effect("shake"); This mini popup has an X for closing it, or else, it will auto close after a few seconds: setTimeout(function() { $('#minipopup').effect("explode"); }, 10000); $('#closePopup').click(function() { $('#minipopup').effect("explode"); }); Everything works, except that, if the user clicks the CLOSE button, he sees the explode effect and the popup effectively dissapears, but after the 10 seconds pass (the one I defined under the setTimeout), the user again sees the popup explosion (just the effect, cause the popup is not there visually). How could I avoid that "ghost" explosion if the user already closed the popup manually? Thanks in advance.

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  • DBnull in Linq query causing problems

    - by nat
    hi there i am doing a query thus: int numberInInterval = (from dsStatistics.J2RespondentRow item in jStats.J2Respondent where item.EndTime > dtIntervalLower && item.EndTime <= dtIntervalUpper select item).count(); there appear to be some dbnulls in the endtime column.. any way i can avoid these? tried adding && where item.endtime != null.. and even != dbnull.value do i have to do a second (first) query to grab all that arent null then run the above one? im sure its super simple fix, but im still missing it.. as per thanks nat

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  • How do I use Zend Cache on this particular problem

    - by davykiash
    I have an action that renders two different view scripts based on whether the user is logged in or not. class IndexController extends Zend_Controller_Action { .... public function indexAction() { $auth = Zend_Auth::getInstance(); if($auth->hasIdentity()) { $this->render('indexregistered'); return; } else { $this->render('indexpublic'); return; } } .... } I have seen quite some useful examples on how to use the Zend Cache and they seem to be based on the fact that the action renders one particular script. What am really looking at is the best approach to cache the the indexpublic script does get quite some hits and I would live to avoid the Zend MVC overhead if possible.

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  • Development deployment: how to achive edit-and-reload with JSP pages?

    - by doublep
    Out project uses WebLogic as web-server and uses mostly JSP for user interface. With standard setup it is possible to copy edited JSP files into the exploded deployment directory and WebLogic will automatically pick them up, recompile and serve new content through HTTP. However, is it possible to avoid copying at all, so that I just save a file in my editor and it is immediately (well, after a couple of seconds for recompilation) visible? The project uses Apache Ant as building tool. I would imagine what I want would be possible with symlinks (since this is for deployment only I don't care about cross-platformity), but then I don't see how it is possible to symlink lots of files at once with Ant. So, how do I achieve save-JSP-hit-F5-in-browser functionality either with some setting in WebLogic; or with symlinking JSPs using Apache Ant (instead of copying them as is done now); or something else completely?

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  • Rails reserved words and convention

    - by PatrickLightning
    After having spent a lot of time researching Rails reserved words and implementing, I still have a few questions regarding use. In my example here, I'll consider the reserved word 'time'. Let's say I want to create a class 'Timepiece'. Is it not recommended to use 'timepiece' because the name begins with 'time'? Would it be recommended to use 'time_piece' or to avoid inserting the reserved word at all? My question here is also about use of the exact reserved word within the class like that. Thank you.

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  • Pointer to auto_ptr instead of a classical double pointer

    - by Pin
    Hello. I'm quite new to smart pointers and was trying to refactor some existing code to use auto_ptr. The question I have is about double pointers and their auto_ptr equivalent, if that makes sense. I have a function that accepts a double pointer as its parameter and the function allocates resources for it: void foo ( Image** img ) { ... *img = new Image(); ...} This function is then used like this: Image* img = NULL; foo ( &img ); ... delete img; I want to use auto_ptr to avoid having to call delete explicitly. Is the following correct? void foo ( auto_ptr<Image>* img ); and then auto_ptr<Image> img = NULL; foo ( &img ); Thanks.

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  • Handling Java stdout and stderr in Perl

    - by syker
    I am trying to run a Java program from my Perl script. I would like to avoid using System.exit(1) and System.exit(-1) commands in Java. I am however printing to STDOUT and STDERR from Java. In my Perl script, I am reading from Java's stdout and using that line by line output. How do I print stderr and fail if I ever see stderr? This is what I have so far: my $java_command = ...; open(DATA, ">$java_command"); while (<DATA>) { chomp($_); .... .... }

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  • How to stop toggle event from being fired multiple times on mouseenter/mouseleave?

    - by Clean
    Hi, I'm using jQuery to toggle the visibility of a using the jQuery toggle method. The toggle is fired on the mouseenter and mouseleave event, thus creating the effect of the div to fold out on mouseenter and fold in on mouseleave. Problem is, if the user drags the mouse over the a few times and then leaves the , the div will toggle in and out several times. This can happen if the user accidentally moves around the mouse pointer in the are. Do anyone have any idea on how I can avoid this behavior? Thanx!

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  • linux thread synchronization

    - by johnnycrash
    I am new to linux and linux threads. I have spent some time googling to try to understand the differences between all the functions available for thread synchronization. I still have some questions. I have found all of these different types of synchronizations, each with a number of functions for locking, unlocking, testing the lock, etc. gcc atomic operations futexes mutexes spinlocks seqlocks rculocks conditions semaphores My current (but probably flawed) understanding is this: semaphores are process wide, involve the filesystem (virtually I assume), and are probably the slowest. Futexes might be the base locking mechanism used by mutexes, spinlocks, seqlocks, and rculocks. Futexes might be faster than the locking mechanisms that are based on them. Spinlocks dont block and thus avoid context swtiches. However they avoid the context switch at the expense of consuming all the cycles on a CPU until the lock is released (spinning). They should only should be used on multi processor systems for obvious reasons. Never sleep in a spinlock. The seq lock just tells you when you finished your work if a writer changed the data the work was based on. You have to go back and repeat the work in this case. Atomic operations are the fastest synch call, and probably are used in all the above locking mechanisms. You do not want to use atomic operations on all the fields in your shared data. You want to use a lock (mutex, futex, spin, seq, rcu) or a single atomic opertation on a lock flag when you are accessing multiple data fields. My questions go like this: Am I right so far with my assumptions? Does anyone know the cpu cycle cost of the various options? I am adding parallelism to the app so we can get better wall time response at the expense of running fewer app instances per box. Performances is the utmost consideration. I don't want to consume cpu with context switching, spinning, or lots of extra cpu cycles to read and write shared memory. I am absolutely concerned with number of cpu cycles consumed. Which (if any) of the locks prevent interruption of a thread by the scheduler or interrupt...or am I just an idiot and all synchonization mechanisms do this. What kinds of interruption are prevented? Can I block all threads or threads just on the locking thread's CPU? This question stems from my fear of interrupting a thread holding a lock for a very commonly used function. I expect that the scheduler might schedule any number of other workers who will likely run into this function and then block because it was locked. A lot of context switching would be wasted until the thread with the lock gets rescheduled and finishes. I can re-write this function to minimize lock time, but still it is so commonly called I would like to use a lock that prevents interruption...across all processors. I am writing user code...so I get software interrupts, not hardware ones...right? I should stay away from any functions (spin/seq locks) that have the word "irq" in them. Which locks are for writing kernel or driver code and which are meant for user mode? Does anyone think using an atomic operation to have multiple threads move through a linked list is nuts? I am thinking to atomicly change the current item pointer to the next item in the list. If the attempt works, then the thread can safely use the data the current item pointed to before it was moved. Other threads would now be moved along the list. futexes? Any reason to use them instead of mutexes? Is there a better way than using a condition to sleep a thread when there is no work? When using gcc atomic ops, specifically the test_and_set, can I get a performance increase by doing a non atomic test first and then using test_and_set to confirm? *I know this will be case specific, so here is the case. There is a large collection of work items, say thousands. Each work item has a flag that is initialized to 0. When a thread has exclusive access to the work item, the flag will be one. There will be lots of worker threads. Any time a thread is looking for work, they can non atomicly test for 1. If they read a 1, we know for certain that the work is unavailable. If they read a zero, they need to perform the atomic test_and_set to confirm. So if the atomic test_and_set is 500 cpu cycles because it is disabling pipelining, causes cpu's to communicate and L2 caches to flush/fill .... and a simple test is 1 cycle .... then as long as I had a better ratio of 500 to 1 when it came to stumbling upon already completed work items....this would be a win.* I hope to use mutexes or spinlocks to sparilngly protect sections of code that I want only one thread on the SYSTEM (not jsut the CPU) to access at a time. I hope to sparingly use gcc atomic ops to select work and minimize use of mutexes and spinlocks. For instance: a flag in a work item can be checked to see if a thread has worked it (0=no, 1=yes or in progress). A simple test_and_set tells the thread if it has work or needs to move on. I hope to use conditions to wake up threads when there is work. Thanks!

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  • jQuery style Constructors in PHP

    - by McB
    Is there a way to instantiate a new PHP object in a similar manner to those in jQuery? I'm talking about assigning a variable number of arguments when creating the object. For example, I know I could do something like: ... //in my Class __contruct($name, $height, $eye_colour, $car, $password) { ... } $p1 = new person("bob", "5'9", "Blue", "toyota", "password"); But I'd like to set only some of them maybe. So something like: $p1 = new person({ name: "bob", eyes: "blue"}); Which is more along the lines of how it is done in jQuery and other frameworks. Is this built in to PHP? Is there a way to do it? Or a reason I should avoid it?

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  • Optimize code perfromance when odd/even threads are doing different things in CUDA

    - by Ashraf
    Hi all! I have two large vectors, I am trying to do some sort of element multiplication, where an even-numbered element in the first vector is multiplied by the next odd-numbered element in the second vector .... and where the odd-numbered element in the first vector is multiplied by the preceding even-numbered element in the second vector Ex. vector 1 is V1(1) V1(2) V1(3) V1(4) vector 2 is V2(1) V2(2) V2(3) V2(4) V1(1) * V2(2) V1(3) * V2(4) V1(2) * V2(1) V1(4) * V2(3) I have written a Cuda code to do this: (Pds has the elements of the first vector in shared memory, Nds the second Vector) //instead of using %2 .. i check for the first bit to decide if number is odd/even -- faster if ((tx & 0x0001) == 0x0000) Nds[tx+1] = Pds[tx] * Nds[tx+1]; else Nds[tx-1] = Pds[tx] * Nds[tx-1]; __syncthreads(); Is there anyway to further accelerate this code or avoid divergence .. Thanks

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  • What to use to create bar, line and pie charts with javascript compatible with all major browsers?

    - by marcgg
    I used to work with flot but it doesn't support pie charts so I'm forced to change. I just saw JS Charts, but their documentation is very obscure regarding cross browser compatibility (I need it to be IE6+ compliant :). Also this will be for commercial use, so I'd rather have something that I can use free of charge jQuery Google chart looks really nice and is well integrated with rails (the framework I'm using) but I'm not sure how good it is. So what do you guys use? What would you recommend keeping in mind that: It will be for commercial use (I can deal with a license, but I'd rather avoid that) It needs to be javascript (no svg, no flash please) It needs to be compatible with IE6+, FF, Chrome, Opera and Safari It needs to be pretty ^^ If it uses jQuery it's even better

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  • Opposite of Bloom filter?

    - by abc
    Hi, I'm trying to optimize a piece of software which is basically running millions of tests. These tests are generated in such a way that there can be some repetitions. Of course, I don't want to spend time running tests which I already ran if I can avoid it efficiently. So, I'm thinking about using a Bloom filter to store the tests which have been already ran. However, the Bloom filter errs on the unsafe side for me. It gives false positives. That is, it may report that I've ran a test which I haven't. Although this could be acceptable in the scenario I'm working on, I was wondering if there's an equivalent to a Bloom filter, but erring on the opposite side, that is, only giving false negatives. I've skimmed through the literature without any luck.

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  • NDIS or TDI for packet redirection to a local proxy

    - by Enrico Detoma
    I need to develop a transparent filter to redirect outgoing HTTP packets to a local proxy, to do transparent content filtering. Which is the best technology to do it, TDI or NDIS IM? My main constraint is to avoid conflicts with antivirus software, which also do some kind of packet redirection to inspect HTTP content (I don't know whether antivirus programs use TDI, NDIS IM, or both). Rather than writing the driver myself, actually, I'm also considering two commercial SDKs for packet filtering/modification: one uses a TDI driver while the other uses a NDIS IM driver, so that's the origin of my question (I was only aware of NDIS IM, before looking at the two SDKs).

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  • Adding pdb files to VSS

    - by George
    Every time I try to compile my web app, I am prompted if i want to add pdb extensioned files to VSS. I thought pdb files do not belong in VSS see a previous post. Is there any way to prevent them from being added. I cannot even logically delete them from VSS because a previous version has been logically deleted and if I were to delete the current version, the previous version would have to be purged, for which I need vss admin rights that I do not have. I just can't get a handle on how to avoid getting a million files added to VSS that prevent otehr develoeprs from compiling their solutions because they have unchecked out read only copies. Is the only solution to check them in but flip the readonly flag off locally? This is not a good option in my mind.

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