Search Results

Search found 4685 results on 188 pages for 'cpp beginner'.

Page 78/188 | < Previous Page | 74 75 76 77 78 79 80 81 82 83 84 85  | Next Page >

  • Beginner iPhone Controller Question

    - by Besha
    I have a view that only has a button UIButton. First time clicking the button will draw a square above the button and the second time will replace the square with a circle. I need some help on writing the controller code. Please guide me to the right path. Thanks

    Read the article

  • C++ beginner question regarding chars

    - by Samwhoo
    I'm just messing around with some C++ at the moment trying to make a simple tic-tac-toe game and I'm running into a bit of a problem. This is my code: #include <iostream> using namespace std; class Square { public: char getState() const; void setState(char); Square(); ~Square(); private: char * pState; }; class Board { public: Board(); ~Board(); void printBoard() const; Square getSquare(short x, short y) const; private: Square board[3][3]; }; int main() { Board board; board.getSquare(1,2).setState('1'); board.printBoard(); return 0; } Square::Square() { pState = new char; *pState = ' '; } Square::~Square() { delete pState; } char Square::getState() const { return *pState; } void Square::setState(char set) { *pState = set; } Board::~Board() { } Board::Board() { } void Board::printBoard() const { for (int x = 0; x < 3; x++) { cout << "|"; for (int y = 0; y < 3; y++) { cout << board[x][y].getState(); } cout << "|" << endl; } } Square Board::getSquare(short x, short y) const { return board[x][y]; } Forgive me if there are blatantly obvious problems with it or it's stupidly written, this is my first program in C++ :p However, the problem is that when I try and set the square 1,2 to the char '1', it doesn't print out as a 1, it prints out as some strange character I didn't recognise. Can anyone tell me why? :) Thanks in advance.

    Read the article

  • Guidance for Php for a beginner

    - by luckyluke
    I've just started to learn PHP. I found the $_POST variable is not working and posted the same at the below link $_POST[] not working in php and as per the advise i installed XAMPP. But still the proble of $_POST variable is not solved. Now i've a doubt whether i need to configure any global variable to make $_POST work. I'm totally lost on this and dont know how to proceed. Any help on this is verryy much appreciated. Thanks.

    Read the article

  • What Math topics & resources to consider as beginner to indulge the book - Introduction to Algorithm

    - by sector7
    I'm a programmer who's beginning to appreciate the knowledge & usability of Algorithms in my work as I move forward with my skill-set. I don't want to take the short path by learning how to apply algorithms "as-is" but would rather like to know the foundation and fundamentals behind them. For that I need Math, at which I'm pretty "basic". I'm considering getting tuition's for that. What I would like is to have a concise syllabus/set of topics/book which I could hand over to my math tutor to get started. HIGHLY DESIRED: one book. the silver bullet. (fingers crossed!) PS: I've got some leads but want to hear you guys/gurus out: Discrete Math, Combinatorics, Graph theory, Calculus, Linear Algebra, and Number Theory. Looking forward to your answers. Thanks!

    Read the article

  • Beginner for Delphi Network!

    - by Blagoj
    Hello, I worked in Delphi 6 a few years. Now I was beginning in Delphi network and I need some source code For following things: I want make chat application which to have two peer to peer clients But I don’t know how I to measure time for two clients and show it on both Screens. I also want to mark first client with 1,second with 2 ,,,,, In some application I want to have value who accounting number of sending of both clients Generally does it exist variable which is mutual for both clients?! Can somebody to send me source code of this kind?! Comments in source code will be welcome. Thank You Blagoj [email removed, return to this site for answer(s)]

    Read the article

  • Beginner's Language app

    - by Eiseldora
    Hi I'm a techie with no programing experience. I know html and css, but I'd like to someday be able to make an app for my phone (I have an android) and possibly mobile websites. I made learning a programing language and creating a mobile app a goal for my job, and now my boss would like me to pick a programing language to learn. I found a free open course from MIT (http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-00-introduction-to-computer-science-and-programming-fall-2008/) called introduction to computer science. In the course they teach python, but more importantly it seems they teach how to think like a programmer. When I told my boss about the free online course she didn't think that Python was an appropriate language for me to learn. She'd like me to learn a language that is more similar to one used to make Phone apps. Does anyone out there know a better language for me to pick up that would be similar to Android or iPhone's App language. Thank you

    Read the article

  • Java threads for the beginner

    - by Boba
    I've been trying to explain Java threading to a colleague who has never been exposed to multi-threaded applications, but apparently I'm not a very good teacher. Can anyone recommend a good online or offline resource that can explain threading in a simple, step-by-step manner? I know it's a complex topic, but surely there exists an article, book, or other explanation that can result in an "Aha! I get it, finally!" moment.

    Read the article

  • Getting bizarre "expected primary-expression" error.

    - by Fecal Brunch
    Hi, I'm getting a really strange error when making a method call: /* input.cpp */ #include <ncurses/ncurses.h> #include "input.h" #include "command.h" Input::Input () { raw (); noecho (); } Command Input::next () { char input = getch (); Command nextCommand; switch (input) { case 'h': nextCommand.setAction (ACTION_MOVELEFT); break; case 'j': nextCommand.setAction (ACTION_MOVEDOWN); break; case 'k': nextCommand.setAction (ACTION_MOVEUP); break; case 'l': nextCommand.setAction (ACTION_MOVERIGHT); break; case 'y': nextCommand.setAction (ACTION_MOVEUPLEFT); break; case 'u': nextCommand.setAction (ACTION_MOVEUPRIGHT); break; case 'n': nextCommand.setAction (ACTION_MOVEDOWNLEFT); break; case 'm': nextCommand.setAction (ACTION_MOVEDOWNRIGHT); break; case '.': nextCommand.setAction (ACTION_WAIT); break; } return nextCommand; } and the error: Administrator@RHYS ~/code/rogue2 $ make g++ -c -Wall -pedantic -g3 -O0 input.cpp input.cpp: In member function `Command Input::next()': input.cpp:21: error: expected primary-expression before '=' token input.cpp:24: error: expected primary-expression before '=' token input.cpp:27: error: expected primary-expression before '=' token input.cpp:30: error: expected primary-expression before '=' token input.cpp:33: error: expected primary-expression before '=' token input.cpp:36: error: expected primary-expression before '=' token input.cpp:39: error: expected primary-expression before '=' token input.cpp:42: error: expected primary-expression before '=' token input.cpp:45: error: expected primary-expression before '=' token make: *** [input.o] Error 1 Sorry about the lack of linenumbers, the errors occur on the lines "nextCommand.setAction(...)", which is totally bizarre considering that they don't contain a '='. Any ideas? Thanks, Rhys

    Read the article

  • Using sem_t in a Qt Project

    - by thauburger
    Hi everyone, I'm working on a simulation in Qt (C++), and would like to make use of a Semaphore wrapper class I made for the sem_t type. Although I am including semaphore.h in my wrapper class, running qmake provides the following error: 'sem_t does not name a type' I believe this is a library/linking error, since I can compile the class without problems from the command line. I've read that you can specify external libraries to include during compilation. However, I'm a) not sure how to do this in the project file, and b) not sure which library to include in order to access semaphore.h. Any help would be greatly appreciated. Thanks, Tom Here's the wrapper class for reference: Semaphore.h #ifndef SEMAPHORE_H #define SEMAPHORE_H #include <semaphore.h> class Semaphore { public: Semaphore(int initialValue = 1); int getValue(); void wait(); void post(); private: sem_t mSemaphore; }; #endif Semaphore.cpp #include "Semaphore.h" Semaphore::Semaphore(int initialValue) { sem_init(&mSemaphore, 0, initialValue); } int Semaphore::getValue() { int value; sem_getvalue(&mSemaphore, &value); return value; } void Semaphore::wait() { sem_wait(&mSemaphore); } void Semaphore::post() { sem_post(&mSemaphore); } And, the QT Project File: TARGET = RestaurantSimulation TEMPLATE = app QT += SOURCES += main.cpp \ RestaurantGUI.cpp \ RestaurantSetup.cpp \ WidgetManager.cpp \ RestaurantView.cpp \ Table.cpp \ GUIFood.cpp \ GUIItem.cpp \ GUICustomer.cpp \ GUIWaiter.cpp \ Semaphore.cpp HEADERS += RestaurantGUI.h \ RestaurantSetup.h \ WidgetManager.h \ RestaurantView.h \ Table.h \ GUIFood.h \ GUIItem.h \ GUICustomer.h \ GUIWaiter.h \ Semaphore.h FORMS += RestaurantSetup.ui LIBS += Full Compiler Output: g++ -c -pipe -g -gdwarf-2 -arch i386 -Wall -W -DQT_GUI_LIB -DQT_CORE_LIB -DQT_SHARED - I/usr/local/Qt4.6/mkspecs/macx-g++ -I. - I/Library/Frameworks/QtCore.framework/Versions/4/Headers -I/usr/include/QtCore - I/Library/Frameworks/QtGui.framework/Versions/4/Headers -I/usr/include/QtGui - I/usr/include -I. -I. -F/Library/Frameworks -o main.o main.cpp In file included from RestaurantGUI.h:10, from main.cpp:2: Semaphore.h:14: error: 'sem_t' does not name a type make: *** [main.o] Error 1 make: Leaving directory `/Users/thauburger/Desktop/RestaurantSimulation' Exited with code 2. Error while building project RestaurantSimulation When executing build step 'Make'

    Read the article

  • OSX / Kernel extensions: problem locating a driver (that extends IOSCSIPeripheralDeviceType00)

    - by LG
    Hi, I'm implementing a driver that extends IOSCSIPeripheralDeviceType00 as I need to send custom SCSI commands to a device. I'm following the VendorSpecificType00 and SimpleUserClient examples and http://wagerlabs.com/writing-a-mac-osx-usb-device-driver-that-impl as an example. I built my kernel extension and it loads fine with kextload and it shows up in kextstat. The problem is that I can't locate it in my user space code. Here's the important (I think) part of: my driver code: #define super IOSCSIPeripheralDeviceType00 OSDefineMetaClassAndStructors(com_mycompany_driver_Foo, IOSCSIPeripheralDeviceType00) my user client code: #define super IOUserClient OSDefineMetaClassAndStructors(com_mycompany_driver_FooUserClient, IOUserClient) the plist: CFBundleIdentifier -> com.mycompany.driver.Foo IOCLass -> com_mycompany_driver_Foo IOUserClientClass -> com_mycompany_driver_FooUserClient IOProviderClass -> IOSCSIPeripheralDeviceNub Here's how I try to locate the driver in my user space code (similar to SimpleUserClient): dictRef = IOServiceMatching("com_mycompany_driver_Foo"); kernResult = IOServiceGetMatchingServices(kIOMasterPortDefault, dictRef, &iterator); When I execute the code, iterator is 0. I noticed that in the VendorSpecificType00 code, the localization of the driver is done differently: dictRef = IOServiceMatching("IOBlockStorageServices"); kr = IOServiceGetMatchingServices(kIOMasterPortDefault, dictRef, &iter); while ((service = IOIteratorNext(iter))) { io_registry_entry_t parent; kr = IORegistryEntryGetParentEntry(service, kIOServicePlane, &parent); ... // We're only interested in the parent object if it's our driver class. if (IOObjectConformsTo(parent, "com_apple_dts_driver_VendorSpecificType00")) { I tried doing that but it didn't work either. Thanks for reading and your help, -L

    Read the article

  • Changing code at runtime

    - by Pagis
    I have a pointer to a function (which i get from a vtable) and I want to edit the function by changing the assembler code (changing a few bytes) at runtime. I tried using memset and also tried assigning the new value directly (something like mPtr[0] = X, mPtr[1] = Y etc.) but I keep getting segmentation fault. How can I change the code? (I'm using C++)

    Read the article

  • Why did this work with Visual C++, but not with gcc?

    - by Carlos Nunez
    I've been working on a senior project for the last several months now, and a major sticking point in our team's development process has been dealing wtih rifts between Visual-C++ and gcc. (Yes, I know we all should have had the same development environment.) Things are about finished up at this point, but I ran into a moderate bug just today that had me wondering whether Visual-C++ is easier on newbies (like me) by design. In one of my headers, there is a function that relies on strtok to chop up a string, do some comparisons and return a string with a similar format. It works a little something like the following: int main() { string a, b, c; //Do stuff with a and b. c = get_string(a,b); } string get_string(string a, string b) { const char * a_ch, b_ch; a_ch = strtok(a.c_str(),","); b_ch = strtok(b.c_str(),","); } strtok is infamous for being great at tokenizing, but equally great at destroying the original string to be tokenized. Thus, when I compiled this with gcc and tried to do anything with a or b, I got unexpected behavior, since the separator used was completely removed in the string. Here's an example in case I'm unclear; if I set a = "Jim,Bob,Mary" and b="Grace,Soo,Hyun", they would be defined as a="JimBobMary" and b="GraceSooHyun" instead of staying the same like I wanted. However, when I compiled this under Visual C++, I got back the original strings and the program executed fine. I tried dynamically allocating memory to the strings and copying them the "standard" way, but the only way that worked was using malloc() and free(), which I hear is discouraged in C++. While I'm curious about that, the real question I have is this: Why did the program work when compiled in VC++, but not with gcc? (This is one of many conflicts that I experienced while trying to make the code cross-platform.) Thanks in advance! -Carlos Nunez

    Read the article

  • Negative execution time

    - by FinalArt2005
    Hello, I wrote a little program that solves 49151 sudoku's within an hour for an assignment, but we had to time it. I thought I'd just let it run and then check the execution time, but it says -1536.087 s. I'm guessing it has to do with the timer being some signed dataype or something, but I have no idea what datatype is used for the timer in the console (code::blocks console, I'm not sure if this is actually a separate console, or just a runner that runs the terminal from the local operating system), so I can't check what the real time was. I'd rather not run this again with some coded timer within my program, since I'd like to be able to use my pc again now. Anybody have any idea what this time could be? It should be somewhere between 40 and 50 minutes, so between 2400 and 3000 seconds. Regards, Erik

    Read the article

  • How, exactly, does the double-stringize trick work?

    - by Peter Hosey
    At least some C preprocessors let you stringize the value of a macro, rather than its name, by passing it through one function-like macro to another that stringizes it: #define STR1(x) #x #define STR2(x) STR1(x) #define THE_ANSWER 42 #define THE_ANSWER_STR STR2(THE_ANSWER) /* "42" */ Example use cases here. This does work, at least in GCC and Clang (both with -std=c99), but I'm not sure how it works in C-standard terms. Is this behavior guaranteed by C99? If so, how does C99 guarantee it? If not, at what point does the behavior go from C-defined to GCC-defined?

    Read the article

  • What are the lengths/limits C preprocessor as a language creation tool? Where can I learn more about

    - by Weston C
    In his FAQ @ http://www2.research.att.com/~bs/bs_faq.html#bootstrapping, Bjarne Stroustrup says: To build [Cfront, the first C++ compiler], I first used C to write a "C with Classes"-to-C preprocessor. "C with Classes" was a C dialect that became the immediate ancestor to C++... I then wrote the first version of Cfront in "C with Classes". When I read this, it piqued my interest in the C preprocessor. I'd seen its macro capabilities as suitable for simplifying common expressions but hadn't thought about its ability to significantly add to syntax and semantics on the level that I imagine bringing classes to C took. So now I have a couple of questions on my mind: 1) Are there other examples of this approach to bootstrapping a language off of C? 2) Is the source to Stroustrup's original work available anywhere? 3) Where could I learn more about the specifics of utilizing this technique? 4) What are the lengths/limits of that approach? Could one, say, create a set of preprocessor macros that let someone write in something significantly Lisp/Scheme like?

    Read the article

  • CoInternetIsFeatureEnabled in Delphi2010

    - by Elias
    Hello, I am trying to deactivate the annoying sound when clicking a link in WebBrowser control, WITHOUT changing the user registry. I've found documentation that this can be done through CoInternetIsFeatureEnabled, also explained here. But i have no idea how to implement it on Delphi 2010, since i am getting "Undeclared Identifier" error after including URLMon unit into the project and not much documentation out there. Any ideas?

    Read the article

  • Porting C++-code from Windows to Unix: systemcalls colliding with name of functions

    - by marvin2k
    Hi I'm porting some crufty C++ Windows-code to Linux, which uses functions called "open" and "close" inside every class... Very bad style, or? Luckily that wasn't a problem in windows, since their systemcalls are named different. When I try to call the systemcalls open() or close() I'm getting some compiler error about "no matching function for call for class:open()". I can't rename all our functions named "class::open" and "class::close" in the whole code, and I have to use open() and close() since I'm working with serial ports. So my question is: How can I tell the compiler, which open I mean? How can I escape or hide the namespace of a class in C++?

    Read the article

  • Creating new image in a loop using OpenCV

    - by user565415
    I am programing some image conversion code with OpenCV and I don't know how can I create image memory buffer to load image on every iteration. I have number of iteration (maxImNumber) and I have an input image. In every loop program must create image that is resized and modified input image. Here is some basic code (concept). for (int imageIndex = 0; imageIndex < maxImNumber; imageIndex++){ cvCopy(inputImage, images[imageIndex], 0); cvReleaseImage(&inputImage); images[imageIndex+1] = cvCreateImage(cvSize((image[imageIndex]->width)/2, image[imageIndex]->height), IPL_DEPTH_8U, 1); for (i=1; i < image[imageIndex]->height; i++) { index = 0; // for(j=0; j < image[imageIndex]->width ; j=j+2){ // doing some basic matematical operation on image content and store it to new image images[imageIndex+1][i][index] = (image[imageIndex][i][j] + image[imageIndex][i][j+2])/2; index++ } } inputImage = cvCreateImage(cvSize((image[imageIndex+1]->width), image[imageIndex]->height), IPL_DEPTH_8U, 1); cvCopy(images[imageIndex+1], inputImage, 0); } Can somebody, please, explain how can I create this image buffer (images[]) and allocate memory for it. Also how can I access any image in this buffer? Thank you very much in advance!

    Read the article

  • How to access CWebBrowser class instance (defined in a protected class) in a different class? C++

    - by extintor
    I have been playing with this webbrowser control example I got it working and added some timers using ON_WM_TIMER. Now I would like to access the m_Browser (CWebBrowser class instance) defined inside the protected CMyBrowserView class into a different class. (for example CMyBrowserApp in the code sample) and use .Navigate and other functions. How can I do this? (im using visual studio 6 c++)

    Read the article

  • How do I make a daemon into a stream in PHP

    - by Itay Moav
    I have a daemon (written in C, but I assume it does not really matter) which outputs messages with printf, and can get input and do stuff with this input (again, not really important what, but he sends those messages to a different machine to be saved there in the DB). My question, how can I make this daemon to be a stream in PHP, so I can hook the input/output of, for example, file_put_contents to this stream.

    Read the article

  • scons: overriding build options for one file

    - by Jason S
    Easy question but I don't know the answer. Let's say I have a scons build where my CCFLAGS includes -O1. I have one file needsOptimization.cpp where I would like to override the -O1 with -O2 instead. How could I do this in scons? update: this is what I ended up doing based on bialix's answer: in my SConscript file: Import('env'); env2 = env.Clone(); env2.Append(CCFLAGS=Split('-O2 --asm_listing')); sourceFiles = ['main.cpp','pwm3phase.cpp']; sourceFiles2 = ['serialencoder.cpp','uartTestObject.cpp']; objectFiles = []; objectFiles.append(env.Object(sourceFiles)); objectFiles.append(env2.Object(sourceFiles2)); ... previously this file was: Import('env'); sourceFiles = ['main.cpp','pwm3phase.cpp','serialencoder.cpp','uartTestObject.cpp']; objectFiles = env.Object(sourceFiles); ...

    Read the article

< Previous Page | 74 75 76 77 78 79 80 81 82 83 84 85  | Next Page >