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  • How to reload a tableView i.e call the viewDidLoad method if a condition is met

    - by Kquane Ingram
    The problem is this i need a way to basically erase all the entry data a user placed into my arrays if a condition is met. Im new to Objective-C and iOS programming, but i believed the solution might be in calling the viewDidLoad method, thus it would virtually refresh the applications with the values of the array reset to default. If there is any other logical way of doing this i would appreciate the help. In short i need to refresh the arrays as they were when the application first launched and the user did not select anything. This is the part where i need it to refresh. if ([gradeRecieved objectAtIndex:i]==nil) { break; // if this condition is met the program must begin anew. Edit* I need to recall the - (void)viewDidLoad method here is more of the code. -(IBAction)button:(id)sender{ int i = 0; int sum = 0; int gradeEarned; int creditHours = 3; for ( i=0;i<8 ; i++) { if ([[points objectAtIndex:i] tag]==GradeA.intValue) { [gradeRecieved replaceObjectAtIndex:i withObject:GradeA]; } if ([[points objectAtIndex:i]tag]==GradeB.intValue) { [gradeRecieved replaceObjectAtIndex:i withObject:GradeB]; } if ([[points objectAtIndex:i]tag]==GradeC.intValue){ [gradeRecieved replaceObjectAtIndex:i withObject:GradeC]; } if ([gradeRecieved objectAtIndex:i]==nil) { break; // if this condition is met the program must restart. } } while ( i<[gradeRecieved count]) { if ([gradeRecieved objectAtIndex:i] == GradeA ) { [finArray replaceObjectAtIndex:i withObject:GradeA]; i++; continue; } if ([gradeRecieved objectAtIndex:i] == GradeB ) { [gradeRecieved replaceObjectAtIndex:i withObject:GradeB]; i++; continue; } if ([gradeRecieved objectAtIndex:i] == GradeC ) { [gradeRecieved replaceObjectAtIndex:i withObject:GradeC]; i++; continue; } }

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  • ISO/IEC Website and Charging for C and C++ Standards

    - by Michael Aaron Safyan
    The ISO C Standard (ISO/IEC 9899) and the ISO C++ Standard (ISO/IEC 14882) are not published online; instead, one must purchase the PDF for each of those standards. I am wondering what the rationale is behind this... is it not detrimental to both the C and C++ programming languages that the authoritative specification for these languages is not made freely available and searchable online? Doesn't this encourage the use of possibly inaccurate, non-authoritative sources for information regarding these standards? While I understand that much time and effort has gone into developing the C and C++ standards, I am still somewhat puzzled by the choice to charge for the specification. The OpenGroup Base Specification, for example, is available for free online; they make money buy charging for certification. Does anyone know why the ISO standards committees don't make their revenue in certifying standards compliance, instead of charging for these documents? Also, does anyone know if the ISO standards committee's atrociously looking website is intentionally made to look that way? It's as if they don't want people visiting and buying the spec. One last thing... the C and C++ standards are generally described as "open standards"... while I realize that this means that anyone is permitted to implement the standard, should that definition of "open" be revised? Charging for the standard rather than making it openly available seems contrary to the spirit of openness. P.S. I do have a copy of the ISO/IEC 9899:1999 and ISO/IEC 14882:2003, so please no remarks about being cheap or anything... although if you are tempted to say such things, you might want to consider the high school, undergraduate, and graduate students who might not have all that much extra cash. Also, you might want to consider the fact that the ISO website is really sketchy and they don't even tell you the cost until you proceed to the checkout... doesn't really encourage one to go and get a copy, now does it?

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  • Regex: match a non nested code block

    - by Sylvanas Garde
    I am currently writing a small texteditor. With this texteditor users are able to create small scripts for a very simple scripting engine. For a better overview I want to highlight codeblocks with the same command like GoTo(x,y) or Draw(x,y). To achieve this I want to use Regular Expresions (I am already using it to highlight other things like variables) Here is my Expression (I know it's very ugly): /(?<!GoTo|Draw|Example)(^(?:GoTo|Draw|Example)\(.+\)*?$)+(?!GoTo|Draw|Example)/gm It matches the following: lala GoTo(5656) -> MATCH 1 sdsd GoTo(sdsd) --comment -> MATCH 2 GoTo(23329); -> MATCH 3 Test() GoTo(12) -> MATCH 4 LALA Draw(23) -> MATCH 5 Draw(24) -> MATCH 6 Draw(25) -> MATCH 7 But what I want to achieve is, that the complete "blocks" of the same command are matched. In this case Match 2 & 4 and Match 5 & 6 & 7 should be one match. Tested with http://regex101.com/, the programming lanuage is vb.net. Any advise would be very useful, Thanks in advance!

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  • Operation is not valid due to the current state of the object?

    - by Bill
    I am programming in C#; the code was working about a week ago, however it throws an exception and I don't understand at all what could be wrong with it. Var root = new CalculationNode(); -> Throw exception. In the call stack thats the only thing listed, I've been told that it could be that I need a clean build, but I am open to any ideas or suggestions. Thanks, -Bill Update: Exception's Detail System.InvalidOperationException was unhandled by user code Message=Operation is not valid due to the current state of the object. Source=Calculator.Logic StackTrace: at ~.Calculator.Logic.MyBaseExpressionParser.Parse(String expression) in ~\Source\Calculator.Logic\MyBaseExpressionParser.cs:line 44 at ~.Calculator.Logic.Tests.MyBaseCalculatorServiceTests.BasicMathDivision() in ~\Projects\Tests\Calculator.Logic.Tests\MyBaseCalculatorServiceTests.cs:line 60 InnerException: CalculationNode's code: public sealed calss CalculationNode { public CalculationNode() { this.Left = null; this.Right = null; this.Element = new CalculationElement(); } public CalculationNode Left {get;set;} public CalculationNode Right {get;set;} public CalculationElement Element {get; set;} } CalculationElement's code: public sealed class CalculationElement { public CalculationElement() { Value = string.Empty; IsOperator = false; } public string Value {get; set} public bool IsOperator {get; set} }

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  • Private member vector of vector dynamic memory allocation

    - by Geoffroy
    Hello, I'm new to C++ (I learned programming with Fortran), and I would like to allocate dynamically the memory for a multidimensional table. This table is a private member variable : class theclass{ public: void setdim(void); private: std::vector < std::vector <int> > thetable; } I would like to set the dimension of thetable with the function setdim(). void theclass::setdim(void){ this->thetable.assign(1000,std::vector <int> (2000)); } I have no problem compiling this program, but as I execute it, I've got a segmentation fault. The strange thing for me is that this piece (see under) of code does exactly what I want, except that it doesn't uses the private member variable of my class : std::vector < std::vector < int > > thetable; thetable.assign(1000,std::vector <int> (2000)); By the way, I have no trouble if thetable is a 1D vector. In theclass : std::vector < int > thetable; and if in setdim : this->thetable.assign(1000,2); So my question is : why is there such a difference with "assign" between thetable and this-thetable for a 2D vector? And how should I do to do what I want? Thank-you for your help, Best regards, -- Geoffroy

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  • Android - Temporal & Ancestral Navigation with ViewPager & Fragments

    - by rascuache
    I'm trying to work out the best way to implement the 'ancestral' and 'temporal' navigation (utilising the up button and back buttons), for a music player I'm working on. Currently, the user is presented with a viewpager, and can page between three main fragments (ArtistMain, AlbumMain and SongMain). Upon choosing an item inside that view, a fragment transaction occurs, and the viewpager goes out of view, replaced by a new fragment (AlbumSub, Songsub or player, depending on where the user came from). The user can then navigate deeper, until a song is chosen, and then they are taken to the 'player' screen. I guess the question is: How do I implement all of this conditional navigation? I'm fairly new to android and programming in general, and I just can't seem to come up with an efficient way to achieve this. At the moment, as each fragment is brought into view, the app is checking to see where the user just came from, and then determines where the user should be taken if back or home is called. This means I have a booleans like "fromArtistMain", "fromAlbumSub", and I'm checking for things like "fromSongSub && fromPlayer".. it's all turning into a bit of a mess. I've drawn a diagram (in paint, sorry!!), to depict the navigation I'm trying to achieve. The yellow represents the 'up' button press, the red is the 'back' button press, and blue is just normal navigation. The green arrows are meant to represent the view paging: Any advice is welcome. It might take something really simple that I've just overlooked. Thanks for your time.

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  • Python creating a dictionary and swapping these into another file

    - by satsurae
    Hi all, I have two tab delimited .csv file. From one.csv I have created a dictionary which looks like: 'EB2430': ' "\t"idnD "\t"yjgV "\t"b4267 "\n', 'EB3128': ' "\t"yagE "\t\t"b0268 "\n', 'EB3945': ' "\t"maeB "\t"ypfF "\t"b2463 "\n', 'EB3944': ' "\t"eutS "\t"ypfE "\t"b2462 "\n', I would like to insert the value of the dictionary into the second.csv file which looks like: "EB2430" 36.81 364 222 4 72 430 101 461 1.00E-063 237 "EB3128" 26.04 169 108 6 42 206 17 172 6.00E-006 45.8 "EB3945" 20.6 233 162 6 106 333 33 247 6.00E-005 42.4 "EB3944" 19.07 367 284 6 1 355 1 366 2.00E-023 103 With a resultant output tab delimited: 'EB2430' idnD yjgV b4267 36.81 364 222 4 72 430 101 461 1.00E-063 237 'EB3128' yagE b0268 26.04 169 108 6 42 206 17 172 6.00E-006 45.8 'EB3945' maeB ypfF b2463 20.6 233 162 6 106 333 33 247 6.00E-005 42.4 'EB3944' eutS ypfE b2462 19.07 367 284 6 1 355 1 366 2.00E-023 103 Here is my code for creating the dictionary: f = open ("one.csv", "r") g = open ("second.csv", "r") eb = [] desc = [] di = {} for line in f: for row in f: eb.append(row[1:7]) desc.append(row[7:]) di = dict(zip(eb,desc)) Sorry for it being so long-winded!! I've not been programming for long. Cheers! Sat

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  • ADO.NET Multiple simultaneous reads from an open database.

    - by Deverill
    Answer not needed - my logic was wrong and this question is invalid. Charles helped me see where I went off-tracks. Thanks I have a utility that moves data from one source to another. In the process of writing the record I check to see if it exists and do an update/insert as necessary. The difficulty I have is that as I'm writing the main record info there is a 2nd table for "custom data" that I have to check to see if it exists and do an update/insert for that as well. Example: I may be loading a pencil sharpener that may or may not exist. While I'm writing it into destination it has characteristics such as style, color, etc. and each of them may or may not exist. As written I seem to need to have 2 DataReaders open, one for the sharpener and one to check for and update color. I am new to ADO.NET, but not to programming and it's more complicated than I listed but for sanity's sake I didn't put all the details. My question is: What am I missing? You can't have 2 readers open at the same time on a connection, yet I can't close the first if I'm stepping through all products. It seems inefficient to have 2 connections, readers, etc. for this. Is there a feature of ADO.NET DBs that I'm missing? How would you do it? Thanks!

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  • How to accommodate for the iPhone 4 screen resolution?

    - by dontWatchMyProfile
    This is a programming question! Read on before you vote to close! According to Apple, the iPhone 4 has a new and better screen resolution: 3.5-inch (diagonal) widescreen Multi-Touch display 960-by-640-pixel resolution at 326 ppi This little detail affects our apps in a heavy way. Most of the demo apps on the net have one thing in common: They position views in the believe that the screen has a fixed size of 320 x 480 pixels. So what most -if not all- developers do is: They designed everything in such a way, that a touchable area is -for example- 50 x 50 pixels big. Just enough to tap it. Things have been positioned relative to the upper left, to reach a specific position on screen - let's say the center, or somewhere at the bottom. Edit: It seems Apple has integrated an switch that allows to tell if an app is highRes or not. Nice. When we develop high-resolution apps, they probably won't work on older devices. And if they do, they would suffer a lot from 4-times the size of any image, having to scale them down in memory.

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  • Do complex JOINs cause high coupling and maintenance problems ?

    - by ashkan.kh.nazary
    Our project has ~40 tables with complex relations.A colleague believes in using long join queries which enforces me to learn about tables outside of my module but I think I should not concern about tables not directly related to my module and use data access functions (written by those responsible for other modules) when I need data from them. Let me clarify: I am responsible for the ContactVendor module which enables the customers to contact the vendor and start a conversation about some specific product. Products module has it's own complex tables and relations with functions that encapsulate details (for example i18n, activation, product availability etc ...). Now I need to show the product title of some product related to some conversation between the vendor and customers. I may either write a long query that retrieves the product info along with conversation stuff in one shot (which enforces me to learn about Product tables) OR I may pass the relevant product_id to the get_product_info(int) function. First approach is obviously demanding and introduces many bad practices and things I normally consider fault in programming. The problem with the second approach seems to be the countless mini queries these access functions cause and performance loss is a concern when a loop tries to fetch product titles for 100 products using functions that each perform a separate query. So I'm stuck between "don't code to the implementation, code to interface" and performance. What is the right way of doing things ? UPDATE: I'm specially concerned about possible future modifications to those tables outside of my module. What if the Products module decided to change the way they are doing things? or for some reason modify the schema? It means some other modules would break or malfunction until the change is integrated to them. The usual ripple effect problem.

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  • c# sending sms from computer

    - by I__
    i have this code: private SerialPort port = new SerialPort("COM1", 115200, Parity.None, 8, StopBits.One); Console.WriteLine("Incoming Data:"); port.WriteTimeout = 5000; port.ReadTimeout = 5000; // Attach a method to be called when there is data waiting in the port's buffer port.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived); // Begin communications port.Open(); #region PhoneSMSSetup port.Write("AT+CMGF=1\r\n"); Thread.Sleep(500); port.Write("AT+CNMI=2,2\r\n"); Thread.Sleep(500); port.Write("AT+CSCA=\"+4790002100\"\r\n"); Thread.Sleep(500); #endregion // Enter an application loop which keeps this thread alive Application.Run(); i got it from here: http://www.experts-exchange.com/Programming/Languages/C_Sharp/Q_22832563.html i have a new winforms empty application: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace WindowsFormsApplication1 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { } } } can you please tell me: where exactly would i paste the code? how do i get the code to run? i am sending AT COMMANDS to my cell phone that is attached to the computer

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  • when an autoreleased object is actually released?

    - by psebos
    Hi, I am new in objective-c and I am trying to understand memory management to get it right. After reading the excellent Memory Management Programming Guide for Cocoa by apple my only concern is when actually an autoreleased object is released in an iphone/ipod application. My understanding is at the end of a run loop. But what defines a run loop in the application? So I was wondering whether the following piece of code is right. Assume an object @implementation Test - (NSString *) functionA { NSString *stringA; stringA = [[NSString alloc] initWithString:@"Hello" autorelease] return stringA; } - (NSString *) functionB { NSString *stringB; stringB = [self functionA]; return stringB; } - (NSString *) functionC { NSString *stringC; stringC = [self functionB]; return stringC; } - (void)viewDidLoad { [super viewDidLoad]; (NSString *) p = [self functionC]; NSLog(@"string is %@",p); } @end Is this code valid? From the apple text I understand that the NSString returned from functionA is valid in the scope of functionB. I am not sure whether it is valid in functionC and in viewDidLoad. Thanks!

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  • Strange XCode debugger behavior with UITableView datasource

    - by Tarfa
    Hey guys. I've got a perplexing issue. In my subclassed UITableViewController my datasource methods lose their tableview reference depending on lines of code I put inside the method. For example, in this code block: - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { // Return the number of sections. return 3; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { // Return the number of rows in the section. return 5; } // Customize the appearance of table view cells. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { id i = tableView; static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } // Configure the cell... return cell; } the "id i = tableView;" causes the tableview to become nil (0x0) -- and it causes it to be nil before I ever start stepping into the method. If I insert an assignment statement above the "id i = tableview;" statement: CGFloat x = 5.0; id i = tableView; then tableview retains its pointer (i.e. is not nil) if I place the breakpoint after the "id i = tableView;" line. In other words, the breakpoint must be set after the "id i = tableView"; assignment in order for tableView to retain its pointer. If the breakpoint is set before the assignment is made and I just hang at that breakpoint for a bit then after a couple of seconds the console logs this error message: Assertion failed: (cls), function getName, file /SourceCache/objc4_Sim/objc4-427.5/runtime/objc-runtime-new.mm, line 3990. Although the code works when I don't step through the method, I need my debugger to work! It makes programming kind of challenging when your debugging tools become your enemy. Anyone know what the cause and solution are? Thanks.

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  • SQLite for personal use

    - by ALife
    What are the applications for your personal use that needs a small database like SQLite? I am thinking of trying a few popular databases and SQLite is surely the first one I am planning to try since I know barely nothing about database except some simple programming years ago. I learned that SQLite is good for personal use. But embarrassingly I do not see any application except maybe managing my list of phone numbers/contact info, which has probably a few hundred items. What's your experience? FYI, I use EndNote for my reference and softcopy of books, and I feel iTunes' music/media management is ok since I am not a frequent user anyway. And others? I do lots of coding, but I just use some simple etags tools for that. And I pretty much use .txt file (sometimes in the asciidoc style) for my notes. I have quite a bunch of notes, but not that many either. So, really, what are your personal applications that need a small database instead of existing tools and plain text files?

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  • How to contain the Deepwater Horizon oil spill? [closed]

    - by Yarin
    This is obviously not programming, but it's important and we're smart people, so let's give it a shot. (BP has actually begun soliciting suggestions for how to deal with the crisis http://www.deepwaterhorizonresponse.com/go/doc/2931/546759/, confirming that they don't have a clue) I'll start with my own proposal... Anchored Chute: A large-diameter, collapsible, flexible tube/hose with a wide mouth on one end is anchored over the leak. There's no need for a hermetic seal, the opening just needs to be big enough to form a canopy over the leak area. The rest of the tubing can just be dumped on the sea floor. Since oil is denser than water, the oily water that flows into the mouth eventually inflates the tube and raises the opposite end to the surface, where it can be collected (Like those inflatable dancing air socks at car dealerships). Further buoyancy could be added with floats attached to the tube at intervals. I think this method would not be as susceptible to the problems BP had with the containment dome, where a rigid, metal casing froze up with crystallized hydrates, as we would not be trying to contain the full pressure of the well, but would be using the natural buoyancy of the oil to channel its flow, and with a much larger opening.

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  • POST xml to php with apache2

    - by Berry
    I'm working on an application that receives XML data via POST, processes it with a PHP script, and returns an XML response. I'm getting the XML with this PHP code: $requestStr = file_get_contents('php://input'); $requests = simplexml_load_string($requestStr); which works fine on the Linux-based product hardware using nginx as the server. However, for testing I'd like to be able to run it on my MacBook Pro, so I can avoid the "build image, install on product, reboot product, wait, test change" loop while I do targeted development on this XML processor. I enabled "web sharing" which starts up Apache, added a rewrite rule to point a convenient URI at my development source directory and used curl to send a request to my PHP script thus: curl -H "Content-Type:text/xml" -d @request.xml http://localhost/test/path/testscript "testscript" is handled by the PHP script fine, but when it goes to read "php:://input" I get nothing -- the empty string. Anyone have a clue why this would work under Linux with nginx and not under MacOS with Apache? I've googled and searched stackoverlow.com to no avail. Thanks for any answers. UPDATE: I've discovered that at least in this configuration, reading from php://stdin will work fine, while php://input will not. Who knew?

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  • Risking the exception anti-pattern.. with some modifications

    - by Sridhar Iyer
    Lets say that I have a library which runs 24x7 on certain machines. Even if the code is rock solid, a hardware fault can sooner or later trigger an exception. I would like to have some sort of failsafe in position for events like this. One approach would be to write wrapper functions that encapsulate each api a: returnCode=DEFAULT; try { returnCode=libraryAPI1(); } catch(...) { returnCode=BAD; } return returnCode; The caller of the library then restarts the whole thread, reinitializes the module if the returnCode is bad. Things CAN go horribly wrong. E.g. if the try block(or libraryAPI1()) had: func1(); char *x=malloc(1000); func2(); if func2() throws an exception, x will never be freed. On a similar vein, file corruption is a possible outcome. Could you please tell me what other things can possibly go wrong in this scenario?

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  • Emailing an excel sheet with SSL in Python

    - by jakecar
    Hi...this is my first post so let me know if there are any common courtesies I should know about. I just started programming 8 months ago, so I am fairly new. I have been doing some projects to get better. A project I'm working on now creates an Excel sheet from inputted data. It's in Python, which I just started learning a couple of weeks ago. I'm attempting to embed part of this Excel sheet into an email, sent from my school address. I have spent hours looking this up, and to no avail. There are two problems I am asking for help with: 1) I have figured out how to send an email from my GMail account, but not from my school address. My school email uses SSL port 465, which I have tried to use, but to no avail. Unfortunately, I have been having a problem setting up outgoing email for this account on my iPhone as well. It may be related? Does anyone know of common issues relating to outgoing email with SSL and Python? 2) Excel has an option of saving a sheet as a HTML. When doing so, I copy and pasted the HTML source and emailed it as an attachment. Unfortunately, the colored text did not transfer over. Does anyone know of a better way of using Python to send an excel sheet embedded in an email? Thanks for your help!

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  • How can I SETF an element in a tree by an accessor?

    - by Willi Ballenthin
    We've been using Lisp in my AI course. The assignments I've received have involved searching and generating tree-like structures. For each assignment, I've ended up writing something like: (defun initial-state () (list 0 ; score nil ; children 0 ; value 0)) ; something else and building my functions around these "states", which are really just nested lists with some loosely defined structure. To make the structure more rigid, I've tried to write accessors, such as: (defun state-score ( state ) (nth 2 state)) This works for reading the value (which should be all I need to do in a nicely functional world. However, as time crunches, and I start to madly hack, sometimes I want a mutable structure). I don't seem to be able to SETF the returned ...thing (place? value? pointer?). I get an error with something like: (setf (state-score *state*) 10) Sometimes I seem to have a little more luck writing the accessor/mutator as a macro: (defmacro state-score ( state ) `(nth 2 ,state)) However I don't know why this should be a macro, so I certainly shouldn't write it as a macro (except that sometimes it works. Programming by coincidence is bad). What is an appropriate strategy to build up such structures? More importantly, where can I learn about whats going on here (what operations affect the memory in what way)?

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  • Automatic testing of GUI related private methods

    - by Stein G. Strindhaug
    When it comes to GUI programming (at least for web) I feel that often the only thing that would be useful to unit test is some of the private methods*. While unit testing makes perfect sense for back-end code, I feel it doesn't quite fit the GUI classes. What is the best way to add automatic testing of these? * Why I think the only methods useful to test is private: Often when I write GUI classes they don't even have any public methods except for the constructor. The public methods if any is trivial, and the constructor does most of the job calling private methods. They receive some data from server does a lot of trivial output and feeds data to the constructor of other classes contained inside it, adding listeners that calls a (more or less directly) calls the server... Most of it pretty trivial (the hardest part is the layout: css, IE, etc.) but sometimes I create some private method that does some advanced tricks, which I definitely do not want to be publicly visible (because it's closely coupled to the implementation of the layout, and likely to change), but is sufficiently complicated to break. These are often only called by the constructor or repeatedly by events in the code, not by any public methods at all. I'd like to have a way to test this type of methods, without making it public or resorting to reflection trickery. (BTW: I'm currently using GWT, but I feel this applies to most languages/frameworks I've used when coding for GUI)

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  • Java Random Slowdowns on Mac OS cont'd

    - by javajustice
    I asked this question a few weeks ago, but I'm still having the problem and I have some new hints. The original question is here: http://stackoverflow.com/questions/1651887/java-random-slowdowns-on-mac-os Basically, I have a java application that splits a job into independent pieces and runs them in separate threads. The threads have no synchronization or shared memory items. The only resources they do share are data files on the hard disk, with each thread having an open file channel. Most of the time it runs very fast, but occasionally it will run very slow for no apparent reason. If I attach a CPU profiler to it, then it will start running quickly again. If I take a CPU snapshot, it says its spending most of its time in "self time" in a function that doesn't do anything except check a few (unshared unsynchronized) booleans. I don't know how this could be accurate because 1, it makes no sense, and 2, attaching the profiler seems to knock the threads out of whatever mode they're in and fix the problem. Also, regardless of whether it runs fast or slow, it always finishes and gives the same output, and it never dips in total cpu usage (in this case ~1500%), implying that the threads aren't getting blocked. I have tried different garbage collectors, different sizings the parts of the memory space, writing data output to non-raid drives, and putting all data output in threads separate the main worker threads. Does anyone have any idea what kind of problem this could be? Could it be the operating system (OS X 10.6.2) ? I have not been able to duplicate it on a windows machine, but I don't have one with a similar hardware configuration.

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  • Will Apple bundle the Mono Touch runtime with every iPhone?

    - by Zoran Simic
    It strikes me as a good idea for Apple to negotiate with Novell and bundle the Mono Touch runtime (only the runtime of course) into every iPhone and iPod Touch. Perhaps even make it a "one time install" that automatically gets downloaded from the App Store the first time one downloads an app build with Mono Touch, making every subsequent Mono Touch app much lighter to download (without the runtime). Doing so would be similar in a way to adding Bootcamp to OS X: it would make it easier for C# developers to join the party, but that wouldn't mean these developers will all stick to C#... What convinced me to buy a Mac is Bootcamp - I figured I could always install Windows if I didn't like OS X (and I liked the hardware, so no problem there). 6 months later, I'm using OS X full time... Would there be any technical issues in doing so? I see only advantages for all parties, not one disadvantage to anyone (except maybe for the few unfortunate Apple employees who would have to test the crap out of the Mono Touch runtime before bundling it): Novell wins because Mono Touch becomes much more viable (Mono Touch apps become much lighter all of the sudden) Developers win because now there's one more tool in the tool belt Many C# Developers would be very interested by this Apple wins because that would bring even more attention to the platform, more revenue in developer fees, more potential great apps, etc Users win because less space is used by different Apps having copies of the same runtime accumulating on their devices Would there be a major technical obstacle in bundling Mono Touch to iPhone OS? Edit: Changed the title from "Should" to "Will Apple bundle the runtime?", I think the consensus on predicting that means a lot to those considering going with Mono Touch.

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  • How to access hidden template in unnamed namespace?

    - by Johannes Schaub - litb
    Here is a tricky situation, and i wonder what ways there are to solve it namespace { template <class T> struct Template { /* ... */ }; } typedef Template<int> Template; Sadly, the Template typedef interferes with the Template template in the unnamed namespace. When you try to do Template<float> in the global scope, the compiler raises an ambiguity error between the template name and the typedef name. You don't have control over either the template name or the typedef-name. Now I want to know whether it is possible to: Create an object of the typedefed type Template (i.e Template<int>) in the global namespace. Create an object of the type Template<float> in the global namespace. You are not allowed to add anything to the unnamed namespace. Everything should be done in the global namespace. This is out of curiosity because i was wondering what tricks there are for solving such an ambiguity. It's not a practical problem i hit during daily programming.

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  • How can I print text fields at the right coordinates?

    - by Milad
    I don't have any background in programming and this is my first shot. I wrote a Delphi program that is supposed to print on a result sheet. I work in an institute and we have to establish hundreds of result sheets every 2 months. It's really difficult to do that and different handwriting is also an important issue. I have this code: if PrintDialog.Execute() then begin with MyPrinter do begin MyPrinter.BeginDoc();//Start Printing //Prints First Name MyPrinter.Canvas.TextOut(FirstNameX,FirstNameY,EditFirstName.Text); //Prints Last Name MyPrinter.Canvas.TextOut(LastNameX,LastNameY,EditLastName.Text); //Prints Level MyPrinter.Canvas.TextOut(LevelX,LevelY,EditLevel.Text); //Prints Date MyPrinter.Canvas.TextOut(DateX,DateY,MEditDate.Text); //Prints Student Number MyPrinter.Canvas.TextOut(StdNumX,StdNumY,EditStdnumber.Text); .... MyPrinter.EndDoc();//End Printing end; end; I can't get the right coordinates to print properly. Am I missing something? How can I set the right coordinates? You know TPrinter uses pixels to get the coordinates but papers are measured in inches or centimeters. I'm really confused. I appreciate any help.

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  • Systems design question: DB connection management in load-balanced n-tier

    - by aoven
    I'm wondering about the best approach to designing a DB connection manager for a load-balanced n-tier system. Classic n-tier looks like this: Client -> BusinessServer -> DBServer A load-balancing solution as I see it would then look like this: +--> ... +--+ +--> BusinessServer +--+--> SessionServer --+ Client -> Gateway --+--> BusinessServer +--| +--> DBServer +--> BusinessServer +--+--------------------+ +--> ... +--+ As pictured, the business server component is being load-balanced via multiple instances, and a hardware gateway is distributing the load among them. Session server probably needs to be situated outside the load-balancing array, because it manages state, which mustn't be duplicated. Barring any major errors in design so far, what is the best way to implement DB connection management? I've come up with a couple of options, but there may be others I'm not aware of: Introduce a new Broker component between the DBServer and the other components and let it handle the DB connections. The upside is that all the connections can be managed from a single point, which is very convenient. The downside is that now there is an additional "single point of failure" in the system. Other components must go through it for every request that involves DB in some way, which also makes this a bottleneck. Move the DB connection management into BusinessServer and SessionServer components and let each handle its own DB connections. The upside is that there is no additional "single point of failure" or bottleneck components. The downside is that there is also no control over possible conflicts and deadlocks apart from what DBServer itself can provide. What else can be done? FWIW: Technology is .NET, but none of the vendor-specific stacks are used (e.g. no WCF, MSMQ or the like).

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