Search Results

Search found 3511 results on 141 pages for 'const correctness'.

Page 32/141 | < Previous Page | 28 29 30 31 32 33 34 35 36 37 38 39  | Next Page >

  • how to update database table in sqlite3 iphone

    - by Ajeet Kumar Yadav
    Hi I am new in Iphone i am developing application that is use database but i am face problem. In My application I am using table view. I am fetch the value from database in the table view this is done after that we also insert value throw text field in that table of database and display that value in table view.I am also use another table in database table name is Alootikki the value of table alootikki is display in other table view in application and user want to add this table alootikki value in first table of database and display that value in table view when we do this value is display only in the table view this is not write in the database table. when value is display and user want to add other data throw text field then only that add value is show first value is remove from table view. I am not able to solve this plz help me. The code is given bellow for database -(void)Data1 { //////databaseName = @"dataa.sqlite"; databaseName = @"Recipe1.sqlite"; NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDir = [documentPaths objectAtIndex:0]; databasePath =[documentsDir stringByAppendingPathComponent:databaseName]; [self checkAndCreateDatabase]; list1 = [[NSMutableArray alloc] init]; sqlite3 *database; if (sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { if(addStmt == nil) { ////////////const char *sql = "insert into Dataa(item) Values(?)"; const char *sql = " insert into Slist(Incredients ) Values(?)"; if(sqlite3_prepare_v2(database, sql, -1, &addStmt, NULL) != SQLITE_OK) NSAssert1(0, @"Error while creating add statement. '%s'", sqlite3_errmsg(database)); } sqlite3_bind_text(addStmt, 1, [i UTF8String], -1, SQLITE_TRANSIENT); //sqlite3_bind_int(addStmt,1,i); // sqlite3_bind_text(addStmt, 1, [coffeeName UTF8String], -1, SQLITE_TRANSIENT); // sqlite3_bind_double(addStmt, 2, [price doubleValue]); if(SQLITE_DONE != sqlite3_step(addStmt)) NSAssert1(0, @"Error while inserting data. '%s'", sqlite3_errmsg(database)); else //SQLite provides a method to get the last primary key inserted by using sqlite3_last_insert_rowid coffeeID = sqlite3_last_insert_rowid(database); //Reset the add statement. sqlite3_reset(addStmt); // sqlite3_clear_bindings(detailStmt); //} } sqlite3_finalize(addStmt); addStmt = nil; sqlite3_close(database); } -(void)sopinglist { databaseName= @"Recipe1.sqlite"; NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDir = [documentPaths objectAtIndex:0]; databasePath =[documentsDir stringByAppendingPathComponent:databaseName]; [self checkAndCreateDatabase]; list1 = [[NSMutableArray alloc] init]; sqlite3 *database; if (sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { if(addStmt == nil) { ///////////const char *sql = "insert into Dataa(item) Values(?)"; const char *sql = " insert into Slist(Incredients,Recipename,foodtype ) Values(?,?,?)"; ///////////// const char *sql =" Update Slist ( Incredients, Recipename,foodtype) Values(?,?,?)"; if(sqlite3_prepare_v2(database, sql, -1, &addStmt, NULL) != SQLITE_OK) NSAssert1(0, @"Error while creating add statement. '%s'", sqlite3_errmsg(database)); } /////for( NSString * j in k) sqlite3_bind_text(addStmt, 1, [k UTF8String], -1, SQLITE_TRANSIENT); //sqlite3_bind_int(addStmt,1,i); // sqlite3_bind_text(addStmt, 1, [coffeeName UTF8String], -1, SQLITE_TRANSIENT); // sqlite3_bind_double(addStmt, 2, [price doubleValue]); if(SQLITE_DONE != sqlite3_step(addStmt)) NSAssert1(0, @"Error while inserting data. '%s'", sqlite3_errmsg(database)); else //SQLite provides a method to get the last primary key inserted by using sqlite3_last_insert_rowid coffeeID = sqlite3_last_insert_rowid(database); //Reset the add statement. sqlite3_reset(addStmt); // sqlite3_clear_bindings(detailStmt); //} } sqlite3_finalize(addStmt); addStmt = nil; sqlite3_close(database); } -(void)Data { ////////////////databaseName = @"dataa.sqlite"; databaseName = @"Recipe1.sqlite"; NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDir = [documentPaths objectAtIndex:0]; databasePath =[documentsDir stringByAppendingPathComponent:databaseName]; [self checkAndCreateDatabase]; list1 = [[NSMutableArray alloc] init]; sqlite3 *database; if (sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { if(detailStmt == nil) { const char *sql = "Select * from Slist "; if(sqlite3_prepare_v2(database, sql, -1, &detailStmt, NULL) == SQLITE_OK) { //NSLog(@"Hiiiiiii"); //sqlite3_bind_text(detailStmt, 1, [t1 UTF8String], -1, SQLITE_TRANSIENT); //sqlite3_bind_text(detailStmt, 2, [t2 UTF8String], -2, SQLITE_TRANSIENT); //sqlite3_bind_int(detailStmt, 3, t3); while(sqlite3_step(detailStmt) == SQLITE_ROW) { NSLog(@"Helllloooooo"); //NSString *item= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 0)]; NSString *item= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 0)]; char *str=( char*)sqlite3_column_text(detailStmt, 0); if( str) { item = [ NSString stringWithUTF8String:str ]; } else { item= @""; } //+ (NSString*)stringWithCharsIfNotNull: (char*)item /// { // if ( item == NULL ) // return nil; //else // return [[NSString stringWithUTF8String: item] //stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]]; //} //NSString *fame= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 1)]; //NSString *cinemax = [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 2)]; //NSString *big= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 3)]; //pvr1 = pvr; item1=item; //NSLog(@"%@",item1); data = [[NSMutableArray alloc] init]; list *animal=[[list alloc] initWithName:item1]; // Add the animal object to the animals Array [list1 addObject:animal]; //[list1 addObject:item]; } sqlite3_reset(detailStmt); } sqlite3_finalize(detailStmt); // sqlite3_clear_bindings(detailStmt); } } detailStmt = nil; sqlite3_close(database); } (void)recpies { /////////////////////databaseName = @"Data.sqlite"; databaseName = @"Recipe1.sqlite"; NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDir = [documentPaths objectAtIndex:0]; databasePath =[documentsDir stringByAppendingPathComponent:databaseName]; [self checkAndCreateDatabase]; list1 = [[NSMutableArray alloc] init]; sqlite3 *database; if (sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { if(detailStmt == nil) { //////const char *sql = "Select * from Dataa"; const char *sql ="select *from alootikki"; if(sqlite3_prepare_v2(database, sql, -1, &detailStmt, NULL) == SQLITE_OK) { //NSLog(@"Hiiiiiii"); //sqlite3_bind_text(detailStmt, 1, [t1 UTF8String], -1, SQLITE_TRANSIENT); //sqlite3_bind_text(detailStmt, 2, [t2 UTF8String], -2, SQLITE_TRANSIENT); //sqlite3_bind_int(detailStmt, 3, t3); while(sqlite3_step(detailStmt) == SQLITE_ROW) { //NSLog(@"Helllloooooo"); //NSString *item= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 0)]; NSString *item= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 0)]; char *str=( char*)sqlite3_column_text(detailStmt, 0); if( str) { item = [ NSString stringWithUTF8String:str ]; } else { item= @""; } //NSString *fame= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 1)]; //NSString *cinemax = [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 2)]; //NSString *big= [NSString stringWithUTF8String:(char *)sqlite3_column_text(detailStmt, 3)]; //pvr1 = pvr; item1=item; //NSLog(@"%@",item1); data = [[NSMutableArray alloc] init]; list *animal=[[list alloc] initWithName:item1]; // Add the animal object to the animals Array [list1 addObject:animal]; //[list1 addObject:item]; } sqlite3_reset(detailStmt); } sqlite3_finalize(detailStmt); // sqlite3_clear_bindings(detailStmt); } } detailStmt = nil; sqlite3_close(database); }

    Read the article

  • OpenCL: Strange buffer or image bahaviour with NVidia but not Amd

    - by Alex R.
    I have a big problem (on Linux): I create a buffer with defined data, then an OpenCL kernel takes this data and puts it into an image2d_t. When working on an AMD C50 (Fusion CPU/GPU) the program works as desired, but on my GeForce 9500 GT the given kernel computes the correct result very rarely. Sometimes the result is correct, but very often it is incorrect. Sometimes it depends on very strange changes like removing unused variable declarations or adding a newline. I realized that disabling the optimization will increase the probability to fail. I have the most actual display driver in both systems. Here is my reduced code: #include <CL/cl.h> #include <string> #include <iostream> #include <sstream> #include <cmath> void checkOpenCLErr(cl_int err, std::string name){ const char* errorString[] = { "CL_SUCCESS", "CL_DEVICE_NOT_FOUND", "CL_DEVICE_NOT_AVAILABLE", "CL_COMPILER_NOT_AVAILABLE", "CL_MEM_OBJECT_ALLOCATION_FAILURE", "CL_OUT_OF_RESOURCES", "CL_OUT_OF_HOST_MEMORY", "CL_PROFILING_INFO_NOT_AVAILABLE", "CL_MEM_COPY_OVERLAP", "CL_IMAGE_FORMAT_MISMATCH", "CL_IMAGE_FORMAT_NOT_SUPPORTED", "CL_BUILD_PROGRAM_FAILURE", "CL_MAP_FAILURE", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "CL_INVALID_VALUE", "CL_INVALID_DEVICE_TYPE", "CL_INVALID_PLATFORM", "CL_INVALID_DEVICE", "CL_INVALID_CONTEXT", "CL_INVALID_QUEUE_PROPERTIES", "CL_INVALID_COMMAND_QUEUE", "CL_INVALID_HOST_PTR", "CL_INVALID_MEM_OBJECT", "CL_INVALID_IMAGE_FORMAT_DESCRIPTOR", "CL_INVALID_IMAGE_SIZE", "CL_INVALID_SAMPLER", "CL_INVALID_BINARY", "CL_INVALID_BUILD_OPTIONS", "CL_INVALID_PROGRAM", "CL_INVALID_PROGRAM_EXECUTABLE", "CL_INVALID_KERNEL_NAME", "CL_INVALID_KERNEL_DEFINITION", "CL_INVALID_KERNEL", "CL_INVALID_ARG_INDEX", "CL_INVALID_ARG_VALUE", "CL_INVALID_ARG_SIZE", "CL_INVALID_KERNEL_ARGS", "CL_INVALID_WORK_DIMENSION", "CL_INVALID_WORK_GROUP_SIZE", "CL_INVALID_WORK_ITEM_SIZE", "CL_INVALID_GLOBAL_OFFSET", "CL_INVALID_EVENT_WAIT_LIST", "CL_INVALID_EVENT", "CL_INVALID_OPERATION", "CL_INVALID_GL_OBJECT", "CL_INVALID_BUFFER_SIZE", "CL_INVALID_MIP_LEVEL", "CL_INVALID_GLOBAL_WORK_SIZE", }; if (err != CL_SUCCESS) { std::stringstream str; str << errorString[-err] << " (" << err << ")"; throw std::string(name)+(str.str()); } } int main(){ try{ cl_context m_context; cl_platform_id* m_platforms; unsigned int m_numPlatforms; cl_command_queue m_queue; cl_device_id m_device; cl_int error = 0; // Used to handle error codes clGetPlatformIDs(0,NULL,&m_numPlatforms); m_platforms = new cl_platform_id[m_numPlatforms]; error = clGetPlatformIDs(m_numPlatforms,m_platforms,&m_numPlatforms); checkOpenCLErr(error, "getPlatformIDs"); // Device error = clGetDeviceIDs(m_platforms[0], CL_DEVICE_TYPE_GPU, 1, &m_device, NULL); checkOpenCLErr(error, "getDeviceIDs"); // Context cl_context_properties properties[] = { CL_CONTEXT_PLATFORM, (cl_context_properties)(m_platforms[0]), 0}; m_context = clCreateContextFromType(properties, CL_DEVICE_TYPE_GPU, NULL, NULL, NULL); // m_private->m_context = clCreateContext(properties, 1, &m_private->m_device, NULL, NULL, &error); checkOpenCLErr(error, "Create context"); // Command-queue m_queue = clCreateCommandQueue(m_context, m_device, 0, &error); checkOpenCLErr(error, "Create command queue"); //Build program and kernel const char* source = "#pragma OPENCL EXTENSION cl_khr_byte_addressable_store : enable\n" "\n" "__kernel void bufToImage(__global unsigned char* in, __write_only image2d_t out, const unsigned int offset_x, const unsigned int image_width , const unsigned int maxval ){\n" "\tint i = get_global_id(0);\n" "\tint j = get_global_id(1);\n" "\tint width = get_global_size(0);\n" "\tint height = get_global_size(1);\n" "\n" "\tint pos = j*image_width*3+(offset_x+i)*3;\n" "\tif( maxval < 256 ){\n" "\t\tfloat4 c = (float4)(in[pos],in[pos+1],in[pos+2],1.0f);\n" "\t\tc.x /= maxval;\n" "\t\tc.y /= maxval;\n" "\t\tc.z /= maxval;\n" "\t\twrite_imagef(out, (int2)(i,j), c);\n" "\t}else{\n" "\t\tfloat4 c = (float4)(255.0f*in[2*pos]+in[2*pos+1],255.0f*in[2*pos+2]+in[2*pos+3],255.0f*in[2*pos+4]+in[2*pos+5],1.0f);\n" "\t\tc.x /= maxval;\n" "\t\tc.y /= maxval;\n" "\t\tc.z /= maxval;\n" "\t\twrite_imagef(out, (int2)(i,j), c);\n" "\t}\n" "}\n" "\n" "__constant sampler_t imageSampler = CLK_NORMALIZED_COORDS_FALSE | CLK_ADDRESS_CLAMP_TO_EDGE | CLK_FILTER_NEAREST;\n" "\n" "__kernel void imageToBuf(__read_only image2d_t in, __global unsigned char* out, const unsigned int offset_x, const unsigned int image_width ){\n" "\tint i = get_global_id(0);\n" "\tint j = get_global_id(1);\n" "\tint pos = j*image_width*3+(offset_x+i)*3;\n" "\tfloat4 c = read_imagef(in, imageSampler, (int2)(i,j));\n" "\tif( c.x <= 1.0f && c.y <= 1.0f && c.z <= 1.0f ){\n" "\t\tout[pos] = c.x*255.0f;\n" "\t\tout[pos+1] = c.y*255.0f;\n" "\t\tout[pos+2] = c.z*255.0f;\n" "\t}else{\n" "\t\tout[pos] = 200.0f;\n" "\t\tout[pos+1] = 0.0f;\n" "\t\tout[pos+2] = 255.0f;\n" "\t}\n" "}\n"; cl_int err; cl_program prog = clCreateProgramWithSource(m_context,1,&source,NULL,&err); if( -err != CL_SUCCESS ) throw std::string("clCreateProgramWithSources"); err = clBuildProgram(prog,0,NULL,"-cl-opt-disable",NULL,NULL); if( -err != CL_SUCCESS ) throw std::string("clBuildProgram(fromSources)"); cl_kernel kernel = clCreateKernel(prog,"bufToImage",&err); checkOpenCLErr(err,"CreateKernel"); cl_uint imageWidth = 8; cl_uint imageHeight = 9; //Initialize datas cl_uint maxVal = 255; cl_uint offsetX = 0; int size = imageWidth*imageHeight*3; int resSize = imageWidth*imageHeight*4; cl_uchar* data = new cl_uchar[size]; cl_float* expectedData = new cl_float[resSize]; for( int i = 0,j=0; i < size; i++,j++ ){ data[i] = (cl_uchar)i; expectedData[j] = (cl_float)i/255.0f; if ( i%3 == 2 ){ j++; expectedData[j] = 1.0f; } } cl_mem inBuffer = clCreateBuffer(m_context,CL_MEM_READ_ONLY|CL_MEM_COPY_HOST_PTR,size*sizeof(cl_uchar),data,&err); checkOpenCLErr(err, "clCreateBuffer()"); clFinish(m_queue); cl_image_format imgFormat; imgFormat.image_channel_order = CL_RGBA; imgFormat.image_channel_data_type = CL_FLOAT; cl_mem outImg = clCreateImage2D( m_context, CL_MEM_READ_WRITE, &imgFormat, imageWidth, imageHeight, 0, NULL, &err ); checkOpenCLErr(err,"get2DImage()"); clFinish(m_queue); size_t kernelRegion[]={imageWidth,imageHeight}; size_t kernelWorkgroup[]={1,1}; //Fill kernel with data clSetKernelArg(kernel,0,sizeof(cl_mem),&inBuffer); clSetKernelArg(kernel,1,sizeof(cl_mem),&outImg); clSetKernelArg(kernel,2,sizeof(cl_uint),&offsetX); clSetKernelArg(kernel,3,sizeof(cl_uint),&imageWidth); clSetKernelArg(kernel,4,sizeof(cl_uint),&maxVal); //Run kernel err = clEnqueueNDRangeKernel(m_queue,kernel,2,NULL,kernelRegion,kernelWorkgroup,0,NULL,NULL); checkOpenCLErr(err,"RunKernel"); clFinish(m_queue); //Check resulting data for validty cl_float* computedData = new cl_float[resSize];; size_t region[]={imageWidth,imageHeight,1}; const size_t offset[] = {0,0,0}; err = clEnqueueReadImage(m_queue,outImg,CL_TRUE,offset,region,0,0,computedData,0,NULL,NULL); checkOpenCLErr(err, "readDataFromImage()"); clFinish(m_queue); for( int i = 0; i < resSize; i++ ){ if( fabs(expectedData[i]-computedData[i])>0.1 ){ std::cout << "Expected: \n"; for( int j = 0; j < resSize; j++ ){ std::cout << expectedData[j] << " "; } std::cout << "\nComputed: \n"; std::cout << "\n"; for( int j = 0; j < resSize; j++ ){ std::cout << computedData[j] << " "; } std::cout << "\n"; throw std::string("Error, computed and expected data are not the same!\n"); } } }catch(std::string& e){ std::cout << "\nCaught an exception: " << e << "\n"; return 1; } std::cout << "Works fine\n"; return 0; } I also uploaded the source code for you to make it easier to test it: http://www.file-upload.net/download-3513797/strangeOpenCLError.cpp.html Please can you tell me if I've done wrong anything? Is there any mistake in the code or is this a bug in my driver? Best reagards, Alex

    Read the article

  • The Incremental Architect&acute;s Napkin - #2 - Balancing the forces

    - by Ralf Westphal
    Originally posted on: http://geekswithblogs.net/theArchitectsNapkin/archive/2014/06/02/the-incremental-architectacutes-napkin---2---balancing-the-forces.aspxCategorizing requirements is the prerequisite for ecconomic architectural decisions. Not all requirements are created equal. However, to truely understand and describe the requirement forces pulling on software development, I think further examination of the requirements aspects is varranted. Aspects of Functionality There are two sides to Functionality requirements. It´s about what a software should do. I call that the Operations it implements. Operations are defined by expressions and control structures or calls to frameworks of some sort, i.e. (business) logic statements. Operations calculate, transform, aggregate, validate, send, receive, load, store etc. Operations are about behavior; they take input and produce output by considering state. I´m not using the term “function” here, because functions - or methods or sub-programs - are not necessary to implement Operations. Functions belong to a different sub-aspect of requirements (see below). Operations alone are not enough, though, to make a customer happy with regard to his/her Functionality requirements. Only correctly implemented Operations provide full value. This should make clear, why testing is so important. And not just manual tests during development of some operational feature, but automated tests. Because only automated tests scale when over time the number of operations increases. Without automated tests there is no guarantee formerly correct operations are still correct after more got added. To retest all previous operations manually is infeasible. So whoever relies just on manual tests is not really balancing the two forces Operations and Correctness. With manual tests more weight is put on the side of the scale of Operations. That might be ok for a short period of time - but in the long run it will bite you. You need to plan for Correctness in the long run from the first day of your project on. Aspects of Quality As important as Functionality is, it´s not the driver for software development. No software has ever been written to just implement some operation in code. We don´t need computers just to do something. All computers can do with software we can do without them. Well, at least given enough time and resources. We could calculate the most complex formulas without computers. We could do auctions with millions of people without computers. The only reason we want computers to help us with this and a million other Operations is… We don´t want to wait for the results very long. Or we want less errors. Or we want easier accessability to complicated solutions. So the main reason for customers to buy/order software is some Quality. They want some Functionality with a higher Quality (e.g. performance, scalability, usability, security…) than without the software. But Qualities come in at least two flavors: Most important are Primary Qualities. That´s the Qualities software truely is written for. Take an online auction website for example. Its Primary Qualities are performance, scalability, and usability, I´d say. Auctions should come within reach of millions of people; setting up an auction should be very easy; finding a suitable auction and bidding on it should be as fast as possible. Only if those Qualities have been implemented does security become relevant. A secure auction website is important - but not as important as a fast auction website. Nobody would want to use the most secure auction website if it was unbearably slow. But there would be people willing to use the fastest auction website even it was lacking security. That´s why security - with regard to online auction software - is not a Primary Quality, but just a Secondary Quality. It´s a supporting quality, so to speak. It does not deliver value by itself. With a password manager software this might be different. There security might be a Primary Quality. Please get me right: I don´t want to denigrate any Quality. There´s a long list of non-functional requirements at Wikipedia. They are all created equal - but that does not mean they are equally important for all software projects. When confronted with Quality requirements check with the customer which are primary and which are secondary. That will help to make good economical decisions when in a crunch. Resources are always limited - but requirements are a bottomless ocean. Aspects of Security of Investment Functionality and Quality are traditionally the requirement aspects cared for most - by customers and developers alike. Even today, when pressure rises in a project, tunnel vision will focus on them. Any measures to create and hold up Security of Investment (SoI) will be out of the window pretty quickly. Resistance to customers and/or management is futile. As long as SoI is not placed on equal footing with Functionality and Quality it´s bound to suffer under pressure. To look closer at what SoI means will help to become more conscious about it and make customers and management aware of the risks of neglecting it. SoI to me has two facets: Production Efficiency (PE) is about speed of delivering value. Customers like short response times. Short response times mean less money spent. So whatever makes software development faster supports this requirement. This must not lead to duct tape programming and banging out features by the dozen, though. Because customers don´t just want Operations and Quality, but also Correctness. So if Correctness gets compromised by focussing too much on Production Efficiency it will fire back. Customers want PE not just today, but over the whole course of a software´s lifecycle. That means, it´s not just about coding speed, but equally about code quality. If code quality leads to rework the PE is on an unsatisfactory level. Also if code production leads to waste it´s unsatisfactory. Because the effort which went into waste could have been used to produce value. Rework and waste cost money. Rework and waste abound, however, as long as PE is not addressed explicitly with management and customers. Thanks to the Agile and Lean movements that´s increasingly the case. Nevertheless more could and should be done in many teams. Each and every developer should keep in mind that Production Efficiency is as important to the customer as Functionality and Quality - whether he/she states it or not. Making software development more efficient is important - but still sooner or later even agile projects are going to hit a glas ceiling. At least as long as they neglect the second SoI facet: Evolvability. Delivering correct high quality functionality in short cycles today is good. But not just any software structure will allow this to happen for an indefinite amount of time.[1] The less explicitly software was designed the sooner it´s going to get stuck. Big ball of mud, monolith, brownfield, legacy code, technical debt… there are many names for software structures that have lost the ability to evolve, to be easily changed to accomodate new requirements. An evolvable code base is the opposite of a brownfield. It´s code which can be easily understood (by developers with sufficient domain expertise) and then easily changed to accomodate new requirements. Ideally the costs of adding feature X to an evolvable code base is independent of when it is requested - or at least the costs should only increase linearly, not exponentially.[2] Clean Code, Agile Architecture, and even traditional Software Engineering are concerned with Evolvability. However, it seems no systematic way of achieving it has been layed out yet. TDD + SOLID help - but still… When I look at the design ability reality in teams I see much room for improvement. As stated previously, SoI - or to be more precise: Evolvability - can hardly be measured. Plus the customer rarely states an explicit expectation with regard to it. That´s why I think, special care must be taken to not neglect it. Postponing it to some large refactorings should not be an option. Rather Evolvability needs to be a core concern for every single developer day. This should not mean Evolvability is more important than any of the other requirement aspects. But neither is it less important. That´s why more effort needs to be invested into it, to bring it on par with the other aspects, which usually are much more in focus. In closing As you see, requirements are of quite different kinds. To not take that into account will make it harder to understand the customer, and to make economic decisions. Those sub-aspects of requirements are forces pulling in different directions. To improve performance might have an impact on Evolvability. To increase Production Efficiency might have an impact on security etc. No requirement aspect should go unchecked when deciding how to allocate resources. Balancing should be explicit. And it should be possible to trace back each decision to a requirement. Why is there a null-check on parameters at the start of the method? Why are there 5000 LOC in this method? Why are there interfaces on those classes? Why is this functionality running on the threadpool? Why is this function defined on that class? Why is this class depending on three other classes? These and a thousand more questions are not to mean anything should be different in a code base. But it´s important to know the reason behind all of these decisions. Because not knowing the reason possibly means waste and having decided suboptimally. And how do we ensure to balance all requirement aspects? That needs practices and transparency. Practices means doing things a certain way and not another, even though that might be possible. We´re dealing with dangerous tools here. Like a knife is a dangerous tool. Harm can be done if we use our tools in just any way at the whim of the moment. Over the centuries rules and practices have been established how to use knifes. You don´t put them in peoples´ legs just because you´re feeling like it. You hand over a knife with the handle towards the receiver. You might not even be allowed to cut round food like potatos or eggs with it. The same should be the case for dangerous tools like object-orientation, remote communication, threads etc. We need practices to use them in a way so requirements are balanced almost automatically. In addition, to be able to work on software as a team we need transparency. We need means to share our thoughts, to work jointly on mental models. So far our tools are focused on working with code. Testing frameworks, build servers, DI containers, intellisense, refactoring support… That´s all nice and well. I don´t want to miss any of that. But I think it´s not enough. We´re missing mental tools, tools for making thinking and talking about software (independently of code) easier. You might think, enough of such tools already exist like all those UML diagram types or Flow Charts. But then, isn´t it strange, hardly any team is using them to design software? Or is that just due to a lack of education? I don´t think so. It´s a matter value/weight ratio: the current mental tools are too heavy weight compared to the value they deliver. So my conclusion is, we need lightweight tools to really be able to balance requirements. Software development is complex. We need guidance not to forget important aspects. That´s like with flying an airplane. Pilots don´t just jump in and take off for their destination. Yes, there are times when they are “flying by the seats of their pants”, when they are just experts doing thing intuitively. But most of the time they are going through honed practices called checklist. See “The Checklist Manifesto” for very enlightening details on this. Maybe then I should say it like this: We need more checklists for the complex businss of software development.[3] But that´s what software development mostly is about: changing software over an unknown period of time. It needs to be corrected in order to finally provide promised operations. It needs to be enhanced to provide ever more operations and qualities. All this without knowing when it´s going to stop. Probably never - until “maintainability” hits a wall when the technical debt is too large, the brownfield too deep. Software development is not a sprint, is not a marathon, not even an ultra marathon. Because to all this there is a foreseeable end. Software development is like continuously and foreever running… ? And sometimes I dare to think that costs could even decrease over time. Think of it: With each feature a software becomes richer in functionality. So with each additional feature the chance of there being already functionality helping its implementation increases. That should lead to less costs of feature X if it´s requested later than sooner. X requested later could stand on the shoulders of previous features. Alas, reality seems to be far from this despite 20+ years of admonishing developers to think in terms of reusability.[1] ? Please don´t get me wrong: I don´t want to bog down the “art” of software development with heavyweight practices and heaps of rules to follow. The framework we need should be lightweight. It should not stand in the way of delivering value to the customer. It´s purpose is even to make that easier by helping us to focus and decreasing waste and rework. ?

    Read the article

  • JSON + 3des encrypt dosen't work

    - by oscurodrago
    i'm trying to pass some JSON data encrypted to my app but seem when i decrypt it my script add some 00 to hexe code making it impossible to be serialized i've tried to pass data uncrypted and crypted and the only difference i found is 00 at the end that is how i read JSON if isn't Encrypted NSLog(@"A) %@", response ); NSMutableArray *json = [NSJSONSerialization JSONObjectWithData:response options:kNilOptions error:&error]; NSLog(@"B) %@", error); that is NSLog Output 2012-03-28 00:43:58.399 VGCollect[5583:f803] A) <5b7b2274 69746c65 223a2252 696c6173 63696174 61206c61 20707269 6d612045 7370616e 73696f6e 65206469 20526167 6e61726f 6b204f64 79737365 79222c22 63617465 676f7279 223a225b 20505356 69746120 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3536345f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2250 68616e74 61737920 53746172 204f6e6c 696e6520 3220616e 63686520 73752069 4f532065 20416e64 726f6964 20222c22 63617465 676f7279 223a225b 20495048 4f4e452c 2050432c 20505356 69746120 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3437355f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2250 72696d69 20536372 65656e73 686f7420 696e2061 6c747261 20726973 6f6c757a 696f6e65 20706572 202e6861 636b5c2f 5c2f7665 72737573 222c2263 61746567 6f727922 3a225b20 50533320 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3437325f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2269 6c206e75 6f766f20 444c4320 64692046 696e616c 2046616e 74617379 20584949 492d3220 636f6e66 65726d61 746f2061 6e636865 20696e20 416d6572 69636122 2c226361 7465676f 7279223a 225b2050 53332c20 58333630 205d222c 22696d67 55726c22 3a22494d 41474553 5c2f3230 31325c2f 30335c2f 30303030 38343439 5f313530 7838302e 6a706722 7d2c7b22 7469746c 65223a22 52656769 73747261 746f2069 6c206d61 72636869 6f205461 6c657320 6f662058 696c6c69 6120696e 20457572 6f706122 2c226361 7465676f 7279223a 225b2050 5333205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 34385f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a225376 656c6174 69202e68 61636b5c 2f5c2f56 65727375 732e2065 202e6861 636b5c2f 5c2f5365 6b616920 6e6f204d 756b6f75 206e6922 2c226361 7465676f 7279223a 225b2050 5333205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 33345f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a22476f 6e205061 6b752050 616b7520 50616b75 2050616b 75204164 76656e74 75726520 756e206e 756f766f 2067696f 636f2064 69204e61 6d636f20 42616e64 6169222c 22636174 65676f72 79223a22 5b203344 53205d22 2c22696d 6755726c 223a2249 4d414745 535c2f32 3031325c 2f30335c 2f303030 30383432 385f3135 30783830 2e6a7067 227d2c7b 22746974 6c65223a 224e756f 76652069 6d6d6167 696e6920 6520696e 666f2064 69204669 72652045 6d626c65 6d204177 616b656e 696e6722 2c226361 7465676f 7279223a 225b2033 4453205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 31365f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a225072 696d6520 696d6d61 67696e69 20646569 206e756f 76692044 4c432064 69204669 6e616c20 46616e74 61737920 58494949 2d32222c 22636174 65676f72 79223a22 5b205053 332c2058 33363020 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3431325f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2249 6e206172 7269766f 20717565 73746f20 41757475 6e6e6f20 45706963 204d6963 6b657920 323a2054 68652050 6f776572 206f6620 54776f22 2c226361 7465676f 7279223a 225b2050 53332c20 5769692c 20583336 30205d22 2c22696d 6755726c 223a2249 4d414745 535c2f32 3031325c 2f30335c 2f303030 30383430 385f3135 30783830 2e6a7067 227d5d> 2012-03-28 00:43:58.410 VGCollect[5583:f803] B) (null) instead that is how i serialize my crypted JSON NSData *decryptBase64 = [GTMBase64 decodeData:response]; NSData *decrypt3DES = [Crypt TripleDES:decryptBase64 encryptOrDecrypt:kCCDecrypt key:@"2b9534b45611cbb2436e625d"]; NSLog(@"A) %@", decrypt3DES ); NSMutableArray *json = [NSJSONSerialization JSONObjectWithData:decrypt3DES options:kNilOptions error:&error]; NSLog(@"B) %@", error); and that is the NSLog output 2012-03-28 00:41:51.525 VGCollect[5529:f803] A) <5b7b2274 69746c65 223a2252 696c6173 63696174 61206c61 20707269 6d612045 7370616e 73696f6e 65206469 20526167 6e61726f 6b204f64 79737365 79222c22 63617465 676f7279 223a225b 20505356 69746120 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3536345f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2250 68616e74 61737920 53746172 204f6e6c 696e6520 3220616e 63686520 73752069 4f532065 20416e64 726f6964 20222c22 63617465 676f7279 223a225b 20495048 4f4e452c 2050432c 20505356 69746120 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3437355f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2250 72696d69 20536372 65656e73 686f7420 696e2061 6c747261 20726973 6f6c757a 696f6e65 20706572 202e6861 636b5c2f 5c2f7665 72737573 222c2263 61746567 6f727922 3a225b20 50533320 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3437325f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2269 6c206e75 6f766f20 444c4320 64692046 696e616c 2046616e 74617379 20584949 492d3220 636f6e66 65726d61 746f2061 6e636865 20696e20 416d6572 69636122 2c226361 7465676f 7279223a 225b2050 53332c20 58333630 205d222c 22696d67 55726c22 3a22494d 41474553 5c2f3230 31325c2f 30335c2f 30303030 38343439 5f313530 7838302e 6a706722 7d2c7b22 7469746c 65223a22 52656769 73747261 746f2069 6c206d61 72636869 6f205461 6c657320 6f662058 696c6c69 6120696e 20457572 6f706122 2c226361 7465676f 7279223a 225b2050 5333205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 34385f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a225376 656c6174 69202e68 61636b5c 2f5c2f56 65727375 732e2065 202e6861 636b5c2f 5c2f5365 6b616920 6e6f204d 756b6f75 206e6922 2c226361 7465676f 7279223a 225b2050 5333205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 33345f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a22476f 6e205061 6b752050 616b7520 50616b75 2050616b 75204164 76656e74 75726520 756e206e 756f766f 2067696f 636f2064 69204e61 6d636f20 42616e64 6169222c 22636174 65676f72 79223a22 5b203344 53205d22 2c22696d 6755726c 223a2249 4d414745 535c2f32 3031325c 2f30335c 2f303030 30383432 385f3135 30783830 2e6a7067 227d2c7b 22746974 6c65223a 224e756f 76652069 6d6d6167 696e6920 6520696e 666f2064 69204669 72652045 6d626c65 6d204177 616b656e 696e6722 2c226361 7465676f 7279223a 225b2033 4453205d 222c2269 6d675572 6c223a22 494d4147 45535c2f 32303132 5c2f3033 5c2f3030 30303834 31365f31 35307838 302e6a70 67227d2c 7b227469 746c6522 3a225072 696d6520 696d6d61 67696e69 20646569 206e756f 76692044 4c432064 69204669 6e616c20 46616e74 61737920 58494949 2d32222c 22636174 65676f72 79223a22 5b205053 332c2058 33363020 5d222c22 696d6755 726c223a 22494d41 4745535c 2f323031 325c2f30 335c2f30 30303038 3431325f 31353078 38302e6a 7067227d 2c7b2274 69746c65 223a2249 6e206172 7269766f 20717565 73746f20 41757475 6e6e6f20 45706963 204d6963 6b657920 323a2054 68652050 6f776572 206f6620 54776f22 2c226361 7465676f 7279223a 225b2050 53332c20 5769692c 20583336 30205d22 2c22696d 6755726c 223a2249 4d414745 535c2f32 3031325c 2f30335c 2f303030 30383430 385f3135 30783830 2e6a7067 227d5d00> 2012-03-28 00:41:51.530 VGCollect[5529:f803] B) Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (Garbage at end.) UserInfo=0x6ccdd40 {NSDebugDescription=Garbage at end.} as u can see the only difference between 2 NSlogs is 00 at the end of second hexcode and the error on serialization of it do u know how fix that ? idk if is needed, that is my script for encrypt data +(NSData*)TripleDES:(NSData*)plainData encryptOrDecrypt:(CCOperation)encryptOrDecrypt key:(NSString*)key { const void *vplainText; size_t plainTextBufferSize; plainTextBufferSize = [plainData length]; vplainText = (const void *)[plainData bytes]; CCCryptorStatus ccStatus; uint8_t *bufferPtr = NULL; size_t bufferPtrSize = 0; size_t movedBytes = 0; // uint8_t ivkCCBlockSize3DES; bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1); bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t)); memset((void *)bufferPtr, 0x0, bufferPtrSize); // memset((void *) iv, 0x0, (size_t) sizeof(iv)); // NSString *key = @"123456789012345678901234"; NSString *initVec = @"init Vec"; const void *vkey = (const void *) [key UTF8String]; const void *vinitVec = (const void *) [initVec UTF8String]; ccStatus = CCCrypt(encryptOrDecrypt, kCCAlgorithm3DES, (kCCOptionPKCS7Padding | kCCOptionECBMode) , vkey, //"123456789012345678901234", //key kCCKeySize3DES, vinitVec, //"init Vec", //iv, vplainText, //"Your Name", //plainText, plainTextBufferSize, (void *)bufferPtr, bufferPtrSize, &movedBytes); NSData *result = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes]; return result; }

    Read the article

  • Add child to scene from within a class.

    - by Fecal Brunch
    Hi, I'm new to flash in general and have been writing a program with two classes that extend MovieClip (Stems and Star). I need to create a new Stems object as a child of the scene when the user stops dragging a Star object, but do not know how to reference the scene from within the Star class's code. I've tried passing the scene into the constructor of the Star and doing sometihng like: this.scene.addChild (new Stems ()); But apparently that's not how to do it... Below is the code for Stems and Stars, any advice would be appreciated greatly. package { import flash.display.MovieClip; import flash.events.*; import flash.utils.Timer; public class Stems extends MovieClip { public const centreX=1026/2; public const centreY=600/2; public var isFlowing:Boolean; public var flowerType:Number; public const outerLimit=210; public const innerLimit=100; public function Stems(fType:Number) { this.isFlowing=false; this.scaleX=this.scaleY= .0007* distanceFromCentre(this.x, this.y); this.setXY(); trace(distanceFromCentre(this.x, this.y)); if (fType==2) { gotoAndStop("Aplant"); } } public function distanceFromCentre(X:Number, Y:Number):int { return (Math.sqrt((X-centreX)*(X-centreX)+(Y-centreY)*(Y-centreY))); } public function rotateAwayFromCentre():void { var theX:int=centreX-this.x; var theY:int = (centreY - this.y) * -1; var angle = Math.atan(theY/theX)/(Math.PI/180); if (theX<0) { angle+=180; } if (theX>=0&&theY<0) { angle+=360; } this.rotation = ((angle*-1) + 90)+180; } public function setXY() { do { var tempX=Math.random()*centreX*2; var tempY=Math.random()*centreY*2; } while (distanceFromCentre (tempX, tempY)>this.outerLimit || distanceFromCentre (tempX, tempY)<this.innerLimit); this.x=tempX; this.y=tempY; rotateAwayFromCentre(); } public function getFlowerType():Number { return this.flowerType; } } } package { import flash.display.MovieClip; import flash.events.*; import flash.utils.Timer; public class Star extends MovieClip { public const sWide=1026; public const sTall=600; public var startingX:Number; public var startingY:Number; public var starColor:Number; public var flicker:Timer; public var canUpdatePos:Boolean=true; public const innerLimit=280; public function Star(color:Number, basefl:Number, factorial:Number) { this.setXY(); this.starColor=color; this.flicker = new Timer (basefl + factorial * (Math.ceil(100* Math.random ()))); this.flicker.addEventListener(TimerEvent.TIMER, this.tick); this.addEventListener(MouseEvent.MOUSE_OVER, this.hover); this.addEventListener(MouseEvent.MOUSE_UP, this.drop); this.addEventListener(MouseEvent.MOUSE_DOWN, this.drag); this.addChild (new Stems (2)); this.flicker.start(); this.updateAnimation(0, false); } public function distanceOK(X:Number, Y:Number):Boolean { if (Math.sqrt((X-(sWide/2))*(X-(sWide/2))+(Y-(sTall/2))*(Y-(sTall/2)))>innerLimit) { return true; } else { return false; } } public function setXY() { do { var tempX=this.x=Math.random()*sWide; var tempY=this.y=Math.random()*sTall; } while (distanceOK (tempX, tempY)==false); this.startingX=tempX; this.startingY=tempY; } public function tick(event:TimerEvent) { if (this.canUpdatePos) { this.setXY(); } this.updateAnimation(0, false); this.updateAnimation(this.starColor, false); } public function updateAnimation(color:Number, bright:Boolean) { var brightStr:String; if (bright) { brightStr="bright"; } else { brightStr="low"; } switch (color) { case 0 : this.gotoAndStop("none"); break; case 1 : this.gotoAndStop("N" + brightStr); break; case 2 : this.gotoAndStop("A" + brightStr); break; case 3 : this.gotoAndStop("F" + brightStr); break; case 4 : this.gotoAndStop("E" + brightStr); break; case 5 : this.gotoAndStop("S" + brightStr); break; } } public function hover(event:MouseEvent):void { this.updateAnimation(this.starColor, true); this.canUpdatePos=false; } public function drop(event:MouseEvent):void { this.stopDrag(); this.x=this.startingX; this.y=this.startingY; this.updateAnimation(0, false); this.canUpdatePos=true; } public function drag(event:MouseEvent):void { this.startDrag(false); this.canUpdatePos=false; } } }

    Read the article

  • How should I delete a child object from within a parent's slot? Possibly boost::asio specific.

    - by kaliatech
    I have written a network server class that maintains a std::set of network clients. The network clients emit a signal to the network server on disconnect (via boost::bind). When a network client disconnects, the client instance needs to be removed from the Set and eventually deleted. I would think this is a common pattern, but I am having problems that might, or might not, be specific to ASIO. I've tried to trim down to just the relevant code: /** NetworkServer.hpp **/ class NetworkServices : private boost::noncopyable { public: NetworkServices(void); ~NetworkServices(void); private: void run(); void onNetworkClientEvent(NetworkClientEvent&); private: std::set<boost::shared_ptr<const NetworkClient>> clients; }; /** NetworkClient.cpp **/ void NetworkServices::run() { running = true; boost::asio::io_service::work work(io_service); //keeps service running even if no operations // This creates just one thread for the boost::asio async network services boost::thread iot(boost::bind(&NetworkServices::run_io_service, this)); while (running) { boost::system::error_code err; try { tcp::socket* socket = new tcp::socket(io_service); acceptor->accept(*socket, err); if (!err) { NetworkClient* networkClient = new NetworkClient(io_service, boost::shared_ptr<tcp::socket>(socket)); networkClient->networkClientEventSignal.connect(boost::bind(&NetworkServices::onNetworkClientEvent, this, _1)); clients.insert(boost::shared_ptr<NetworkClient>(networkClient)); networkClient->init(); //kicks off 1st asynch_read call } } // etc... } } void NetworkServices::onNetworkClientEvent(NetworkClientEvent& evt) { switch(evt.getType()) { case NetworkClientEvent::CLIENT_ERROR : { boost::shared_ptr<const NetworkClient> clientPtr = evt.getClient().getSharedPtr(); // ------ THIS IS THE MAGIC LINE ----- // If I keep this, the io_service hangs. If I comment it out, // everything works fine (but I never delete the disconnected NetworkClient). // If actually deleted the client here I might expect problems because it is the caller // of this method via boost::signal and bind. However, The clientPtr is a shared ptr, and a // reference is being kept in the client itself while signaling, so // I would the object is not going to be deleted from the heap here. That seems to be the case. // Never-the-less, this line makes all the difference, most likely because it controls whether or not the NetworkClient ever gets deleted. clients.erase(clientPtr); //I should probably put this socket clean-up in NetworkClient destructor. Regardless by doing this, // I would expect the ASIO socket stuff to be adequately cleaned-up after this. tcp::socket& socket = clientPtr->getSocket(); try { socket.shutdown(boost::asio::socket_base::shutdown_both); socket.close(); } catch(...) { CommServerContext::error("Error while shutting down and closing socket."); } break; } default : { break; } } } /** NetworkClient.hpp **/ class NetworkClient : public boost::enable_shared_from_this<NetworkClient>, Client { NetworkClient(boost::asio::io_service& io_service, boost::shared_ptr<tcp::socket> socket); virtual ~NetworkClient(void); inline boost::shared_ptr<const NetworkClient> getSharedPtr() const { return shared_from_this(); }; boost::signal <void (NetworkClientEvent&)> networkClientEventSignal; void onAsyncReadHeader(const boost::system::error_code& error, size_t bytes_transferred); }; /** NetworkClient.cpp - onAsyncReadHeader method called from io_service.run() thread as result of an async_read operation. Error condition usually result of an unexpected client disconnect.**/ void NetworkClient::onAsyncReadHeader( const boost::system::error_code& error, size_t bytes_transferred) { if (error) { //Make sure this instance doesn't get deleted from parent/slot deferencing //Alternatively, somehow schedule for future delete? boost::shared_ptr<const NetworkClient> clientPtr = getSharedPtr(); //Signal to service that this client is disconnecting NetworkClientEvent evt(*this, NetworkClientEvent::CLIENT_ERROR); networkClientEventSignal(evt); networkClientEventSignal.disconnect_all_slots(); return; } I believe it's not safe to delete the client from within the slot handler because the function return would be ... undefined? (Interestingly, it doesn't seem to blow up on me though.) So I've used boost:shared_ptr along with shared_from_this to make sure the client doesn't get deleted until all slots have been signaled. It doesn't seem to really matter though. I believe this question is not specific to ASIO, but the problem manifests in a peculiar way when using ASIO. I have one thread executing io_service.run(). All ASIO read/write operations are performed asynchronously. Everything works fine with multiple clients connecting/disconnecting UNLESS I delete my client object from the Set per the code above. If I delete my client object, the io_service seemingly deadlocks internally and no further asynchronous operations are performed unless I start another thread. I have try/catches around the io_service.run() call and have not been able to detect any errors. Questions: Are there best practices for deleting child objects, that are also signal emitters, from within parent slots? Any ideas as to why the io_service is hanging when I delete my network client object?

    Read the article

  • How to make negate_unary work with any type?

    - by Chan
    Hi, Following this question: How to negate a predicate function using operator ! in C++? I want to create an operator ! can work with any functor that inherited from unary_function. I tried: template<typename T> inline std::unary_negate<T> operator !( const T& pred ) { return std::not1( pred ); } The compiler complained: Error 5 error C2955: 'std::unary_function' : use of class template requires template argument list c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 223 1 Graphic Error 7 error C2451: conditional expression of type 'std::unary_negate<_Fn1>' is illegal c:\program files\microsoft visual studio 10.0\vc\include\ostream 529 1 Graphic Error 3 error C2146: syntax error : missing ',' before identifier 'argument_type' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 4 error C2065: 'argument_type' : undeclared identifier c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 2 error C2039: 'argument_type' : is not a member of 'std::basic_ostream<_Elem,_Traits>::sentry' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 222 1 Graphic Error 6 error C2039: 'argument_type' : is not a member of 'std::basic_ostream<_Elem,_Traits>::sentry' c:\program files\microsoft visual studio 10.0\vc\include\xfunctional 230 1 Graphic Any idea? Update Follow "templatetypedef" solution, I got new error: Error 3 error C2831: 'operator !' cannot have default parameters c:\visual studio 2010 projects\graphic\graphic\main.cpp 39 1 Graphic Error 2 error C2808: unary 'operator !' has too many formal parameters c:\visual studio 2010 projects\graphic\graphic\main.cpp 39 1 Graphic Error 4 error C2675: unary '!' : 'is_prime' does not define this operator or a conversion to a type acceptable to the predefined operator c:\visual studio 2010 projects\graphic\graphic\main.cpp 52 1 Graphic Update 1 Complete code: #include <iostream> #include <functional> #include <utility> #include <cmath> #include <algorithm> #include <iterator> #include <string> #include <boost/assign.hpp> #include <boost/assign/std/vector.hpp> #include <boost/assign/std/map.hpp> #include <boost/assign/std/set.hpp> #include <boost/assign/std/list.hpp> #include <boost/assign/std/stack.hpp> #include <boost/assign/std/deque.hpp> struct is_prime : std::unary_function<int, bool> { bool operator()( int n ) const { if( n < 2 ) return 0; if( n == 2 || n == 3 ) return 1; if( n % 2 == 0 || n % 3 == 0 ) return 0; int upper_bound = std::sqrt( static_cast<double>( n ) ); for( int pf = 5, step = 2; pf <= upper_bound; ) { if( n % pf == 0 ) return 0; pf += step; step = 6 - step; } return 1; } }; /* template<typename T> inline std::unary_negate<T> operator !( const T& pred, typename T::argument_type* dummy = 0 ) { return std::not1<T>( pred ); } */ inline std::unary_negate<is_prime> operator !( const is_prime& pred ) { return std::not1( pred ); } template<typename T> inline void print_con( const T& con, const std::string& ms = "", const std::string& sep = ", " ) { std::cout << ms << '\n'; std::copy( con.begin(), con.end(), std::ostream_iterator<typename T::value_type>( std::cout, sep.c_str() ) ); std::cout << "\n\n"; } int main() { using namespace boost::assign; std::vector<int> nums; nums += 1, 3, 5, 7, 9; nums.erase( remove_if( nums.begin(), nums.end(), !is_prime() ), nums.end() ); print_con( nums, "After remove all primes" ); } Thanks, Chan Nguyen

    Read the article

  • Implicit constructor available for all types derived from Base excepted the current type?

    - by Vincent
    The following code sum up my problem : template<class Parameter> class Base {}; template<class Parameter1, class Parameter2, class Parameter> class Derived1 : public Base<Parameter> { }; template<class Parameter1, class Parameter2, class Parameter> class Derived2 : public Base<Parameter> { public : // Copy constructor Derived2(const Derived2& x); // An EXPLICIT constructor that does a special conversion for a Derived2 // with other template parameters template<class OtherParameter1, class OtherParameter2, class OtherParameter> explicit Derived2( const Derived2<OtherParameter1, OtherParameter2, OtherParameter>& x ); // Now the problem : I want an IMPLICIT constructor that will work for every // type derived from Base EXCEPT // Derived2<OtherParameter1, OtherParameter2, OtherParameter> template<class Type, class = typename std::enable_if</* SOMETHING */>::type> Derived2(const Type& x); }; How to restrict an implicit constructor to all classes derived from the parent class excepted the current class whatever its template parameters, considering that I already have an explicit constructor as in the example code ? EDIT : For the implicit constructor from Base, I can obviously write : template<class OtherParameter> Derived2(const Base<OtherParameter>& x); But in that case, do I have the guaranty that the compiler will not use this constructor as an implicit constructor for Derived2<OtherParameter1, OtherParameter2, OtherParameter> ? EDIT2: Here I have a test : (LWS here : http://liveworkspace.org/code/cd423fb44fb4c97bc3b843732d837abc) #include <iostream> template<typename Type> class Base {}; template<typename Type> class Other : public Base<Type> {}; template<typename Type> class Derived : public Base<Type> { public: Derived() {std::cout<<"empty"<<std::endl;} Derived(const Derived<Type>& x) {std::cout<<"copy"<<std::endl;} template<typename OtherType> explicit Derived(const Derived<OtherType>& x) {std::cout<<"explicit"<<std::endl;} template<typename OtherType> Derived(const Base<OtherType>& x) {std::cout<<"implicit"<<std::endl;} }; int main() { Other<int> other0; Other<double> other1; std::cout<<"1 = "; Derived<int> dint1; // <- empty std::cout<<"2 = "; Derived<int> dint2; // <- empty std::cout<<"3 = "; Derived<double> ddouble; // <- empty std::cout<<"4 = "; Derived<double> ddouble1(ddouble); // <- copy std::cout<<"5 = "; Derived<double> ddouble2(dint1); // <- explicit std::cout<<"6 = "; ddouble = other0; // <- implicit std::cout<<"7 = "; ddouble = other1; // <- implicit std::cout<<"8 = "; ddouble = ddouble2; // <- nothing (normal : default assignment) std::cout<<"\n9 = "; ddouble = Derived<double>(dint1); // <- explicit std::cout<<"10 = "; ddouble = dint2; // <- implicit : WHY ?!?! return 0; } The last line worry me. Is it ok with the C++ standard ? Is it a bug of g++ ?

    Read the article

  • error - inherited class field undeclared according to g++

    - by infoholic_anonymous
    I have a code that has the following logic. g++ gives me the error that I have not declared n in my iterator2. What could be wrong? template <typename T> class List{ template <typename TT> class Node; Node<T> *head; /* (...) */ template <bool D> class iterator1{ protected: Node<T> n; public: iterator1( Node<T> *nn ) { n = nn } /* (...) */ }; template <bool D> class iterator2 : public iterator1<D>{ public: iterator2( Node<T> *nn ) : iterator1<D>( nn ) {} void fun( Node<T> *nn ) { n = nn; } /* (...) */ }; }; EDIT : I attach the actual header file. iterator1 would be iterable_frame and iterator2 - switchable_frame. #ifndef LST_H #define LST_H template <typename T> class List { public: template <typename TT> class Node; private: Node<T> *head; public: List() { head = new Node<T>; } ~List() { empty_list(); delete head; } List( const List &l ); inline bool is_empty() const { return head->next[0] == head; } void empty_list(); template <bool DIM> class iterable_frame { protected: Node<T> *head; Node<T> **caret; public: iterable_frame( const List &l ) { head = *(caret = &l.head); } iterable_frame( const iterable_frame &i ) { head = *(caret = i.caret); } ~iterable_frame() {} /* (...) - a few methods follow */ template <bool _DIM> friend class supervised_frame; }; template <bool DIM> class switchable_frame : public iterable_frame<DIM> { Node<T> *main_head; public: switchable_frame( const List& l ) : iterable_frame<DIM>(l) { main_head = head; } inline bool next_frame() { caret = &head->next[!DIM]; head = *caret; return head != main_head; } }; template <bool DIM> class supervised_frame { iterable_frame<DIM> sentinels; iterable_frame<DIM> cells; public: supervised_frame( const List &l ) : sentinels(l), cells(l) {} ~supervised_frame() {} /* (...) - a few methods follow */ }; template <typename TT> class Node { unsigned index[2]; TT num; Node<TT> *next[2]; public: Node( unsigned x = 0, unsigned y = 0 ) { index[0]=x; index[1]=y; next[0] = this; next[1] = this; } Node( unsigned x, unsigned y, TT d ) { index[0]=x; index[1]=y; num=d; next[0] = this; next[1] = this; } Node( const Node &n ) { index[0] = n.index[0]; index[1] = n.index[1]; num = n.num; next[0] = next[1] = this; } ~Node() {} friend class List; }; }; #include "List.cpp" #endif the exact error log is the following: In file included from main.cpp:1: List.h: In member function ‘bool List<T>::switchable_frame<DIM>::next_frame()’: List.h:77: error: ‘caret’ was not declared in this scope

    Read the article

  • Persistence classes in Qt

    - by zarzych
    Hi, I'm porting a medium-sized CRUD application from .Net to Qt and I'm looking for a pattern for creating persistence classes. In .Net I usually created abstract persistence class with basic methods (insert, update, delete, select) for example: public class DAOBase<T> { public T GetByPrimaryKey(object primaryKey) {...} public void DeleteByPrimaryKey(object primaryKey) {...} public List<T> GetByField(string fieldName, object value) {...} public void Insert(T dto) {...} public void Update(T dto) {...} } Then, I subclassed it for specific tables/DTOs and added attributes for DB table layout: [DBTable("note", "note_id", NpgsqlTypes.NpgsqlDbType.Integer)] [DbField("note_id", NpgsqlTypes.NpgsqlDbType.Integer, "NoteId")] [DbField("client_id", NpgsqlTypes.NpgsqlDbType.Integer, "ClientId")] [DbField("title", NpgsqlTypes.NpgsqlDbType.Text, "Title", "")] [DbField("body", NpgsqlTypes.NpgsqlDbType.Text, "Body", "")] [DbField("date_added", NpgsqlTypes.NpgsqlDbType.Date, "DateAdded")] class NoteDAO : DAOBase<NoteDTO> { } Thanks to .Net reflection system I was able to achieve heavy code reuse and easy creation of new ORMs. The simplest way to do this kind of stuff in Qt seems to be using model classes from QtSql module. Unfortunately, in my case they provide too abstract an interface. I need at least transactions support and control over individual commits which QSqlTableModel doesn't provide. Could you give me some hints about solving this problem using Qt or point me to some reference materials? Update: Based on Harald's clues I've implemented a solution that is quite similar to the .Net classes above. Now I have two classes. UniversalDAO that inherits QObject and deals with QObject DTOs using metatype system: class UniversalDAO : public QObject { Q_OBJECT public: UniversalDAO(QSqlDatabase dataBase, QObject *parent = 0); virtual ~UniversalDAO(); void insert(const QObject &dto); void update(const QObject &dto); void remove(const QObject &dto); void getByPrimaryKey(QObject &dto, const QVariant &key); }; And a generic SpecializedDAO that casts data obtained from UniversalDAO to appropriate type: template<class DTO> class SpecializedDAO { public: SpecializedDAO(UniversalDAO *universalDao) virtual ~SpecializedDAO() {} DTO defaultDto() const { return DTO; } void insert(DTO dto) { dao->insert(dto); } void update(DTO dto) { dao->update(dto); } void remove(DTO dto) { dao->remove(dto); } DTO getByPrimaryKey(const QVariant &key); }; Using the above, I declare the concrete DAO class as following: class ClientDAO : public QObject, public SpecializedDAO<ClientDTO> { Q_OBJECT public: ClientDAO(UniversalDAO *dao, QObject *parent = 0) : QObject(parent), SpecializedDAO<ClientDTO>(dao) {} }; From within ClientDAO I have to set some database information for UniversalDAO. That's where my implementation gets ugly because I do it like this: QMap<QString, QString> fieldMapper; fieldMapper["client_id"] = "clientId"; fieldMapper["name"] = "firstName"; /* ...all column <-> field pairs in here... */ dao->setFieldMapper(fieldMapper); dao->setTable("client"); dao->setPrimaryKey("client_id"); I do it in constructor so it's not visible at a first glance for someone browsing through the header. In .Net version it was easy to spot and understand. Do you have some ideas how I could make it better?

    Read the article

  • Qt Linker Errors

    - by Kyle Rozendo
    Hi All, I've been trying to get Qt working (QCreator, QIde and now VS2008). I have sorted out a ton of issues already, but I am now faced with the following build errors, and frankly I'm out of ideas. Error 1 error LNK2019: unresolved external symbol "public: void __thiscall FileVisitor::processFileList(class QStringList)" (?processFileList@FileVisitor@@QAEXVQStringList@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 2 error LNK2019: unresolved external symbol "public: void __thiscall FileVisitor::processEntry(class QString)" (?processEntry@FileVisitor@@QAEXVQString@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 3 error LNK2019: unresolved external symbol "public: class QString __thiscall ArgumentList::getSwitchArg(class QString,class QString)" (?getSwitchArg@ArgumentList@@QAE?AVQString@@V2@0@Z) referenced in function _main codevisitor-test.obj Question1 Error 4 error LNK2019: unresolved external symbol "public: bool __thiscall ArgumentList::getSwitch(class QString)" (?getSwitch@ArgumentList@@QAE_NVQString@@@Z) referenced in function _main codevisitor-test.obj Question1 Error 5 error LNK2019: unresolved external symbol "public: void __thiscall ArgumentList::argsToStringlist(int,char * * const)" (?argsToStringlist@ArgumentList@@QAEXHQAPAD@Z) referenced in function "public: __thiscall ArgumentList::ArgumentList(int,char * * const)" (??0ArgumentList@@QAE@HQAPAD@Z) codevisitor-test.obj Question1 Error 6 error LNK2019: unresolved external symbol "public: __thiscall FileVisitor::FileVisitor(class QString,bool,bool)" (??0FileVisitor@@QAE@VQString@@_N1@Z) referenced in function "public: __thiscall CodeVisitor::CodeVisitor(class QString,bool)" (??0CodeVisitor@@QAE@VQString@@_N@Z) codevisitor-test.obj Question1 Error 7 error LNK2001: unresolved external symbol "public: virtual struct QMetaObject const * __thiscall FileVisitor::metaObject(void)const " (?metaObject@FileVisitor@@UBEPBUQMetaObject@@XZ) codevisitor-test.obj Question1 Error 8 error LNK2001: unresolved external symbol "public: virtual void * __thiscall FileVisitor::qt_metacast(char const *)" (?qt_metacast@FileVisitor@@UAEPAXPBD@Z) codevisitor-test.obj Question1 Error 9 error LNK2001: unresolved external symbol "public: virtual int __thiscall FileVisitor::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@FileVisitor@@UAEHW4Call@QMetaObject@@HPAPAX@Z) codevisitor-test.obj Question1 Error 10 error LNK2001: unresolved external symbol "protected: virtual bool __thiscall FileVisitor::skipDir(class QDir const &)" (?skipDir@FileVisitor@@MAE_NABVQDir@@@Z) codevisitor-test.obj Question1 Error 11 fatal error LNK1120: 10 unresolved externals ... \Visual Studio 2008\Projects\Assignment1\Question1\Question1\Debug\Question1.exe Question1 The code is as follows: #include "argumentlist.h" #include <codevisitor.h> #include <QDebug> void usage(QString appname) { qDebug() << appname << " Usage: \n" << "codevisitor [-r] [-d startdir] [-f filter] [file-list]\n" << "\t-r \tvisitor will recurse into subdirs\n" << "\t-d startdir\tspecifies starting directory\n" << "\t-f filter\tfilename filter to restrict visits\n" << "\toptional list of files to be visited"; } int main(int argc, char** argv) { ArgumentList al(argc, argv); QString appname = al.takeFirst(); /* app name is always first in the list. */ if (al.count() == 0) { usage(appname); exit(1); } bool recursive(al.getSwitch("-r")); QString startdir(al.getSwitchArg("-d")); QString filter(al.getSwitchArg("-f")); CodeVisitor cvis(filter, recursive); if (startdir != QString()) { cvis.processEntry(startdir); } else if (al.size()) { cvis.processFileList(al); } else return 1; qDebug() << "Files Processed: %d" << cvis.getNumFiles(); qDebug() << cvis.getResultString(); return 0; } Thanks in advance, I'm simply stumped.

    Read the article

  • How to immediate send mail without prompt confirmation dialog

    - by lmengyew
    I'm using Delphi XE3 and below is my sample application: unit Unit1; interface uses Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls; type TForm1 = class(TForm) Button1: TButton; procedure Button1Click(Sender: TObject); private function Send(const FromAddr, ToAddr, Subject: String; const AttachFiles: array of string; const MsgBody: String): boolean; end; var Form1: TForm1; implementation uses Winapi.Mapi; {$R *.dfm} procedure TForm1.Button1Click(Sender: TObject); begin Send('', '[email protected]', 'test', [], ''); end; function TForm1.Send(const FromAddr, ToAddr, Subject: String; const AttachFiles: array of string; const MsgBody: String): boolean; var Msg: TMapiMessage; lpSender, lpRecipient: TMapiRecipDesc; Attach: array of TMapiFileDesc; SMTP: TFNMapiSendMail; MAPIModule: HModule; i: integer; S: string; begin Result := False; FillChar(Msg, SizeOf(Msg), 0); Msg.lpszSubject := PAnsiChar(UTF8String(Subject)); Msg.lpszNoteText := PAnsiChar(UTF8String(MsgBody)); if FromAddr <> '' then begin lpSender.ulRecipClass := MAPI_ORIG; lpSender.lpszName := PAnsiChar(UTF8String(FromAddr)); lpSender.lpszAddress := PAnsiChar(UTF8String(FromAddr)); lpSender.ulReserved := 0; lpSender.ulEIDSize := 0; lpSender.lpEntryID := Nil; Msg.lpOriginator := @lpSender; end; if ToAddr <> '' then begin lpRecipient.ulRecipClass := MAPI_TO; lpRecipient.lpszName := PAnsiChar(UTF8String(ToAddr)); lpRecipient.lpszAddress := PAnsiChar(UTF8String(ToAddr)); lpRecipient.ulReserved := 0; lpRecipient.ulEIDSize := 0; lpRecipient.lpEntryID := Nil; Msg.nRecipCount := 1; Msg.lpRecips := @lpRecipient; end; SetLength(Attach, Length(AttachFiles)); FillChar(Attach[0], Length(Attach) * SizeOf(TMapiFileDesc), 0); i := 0; for S in AttachFiles do begin Attach[i].nPosition := Cardinal($FFFFFFFF); Attach[i].lpszPathName := PAnsiChar(UTF8String(S)); Inc(i); end; Msg.nFileCount := Length(AttachFiles); if Msg.nFileCount = 0 then Msg.lpFiles := nil else Msg.lpFiles := @Attach[0]; MAPIModule := LoadLibrary(PChar(MAPIDLL)); if MAPIModule <> 0 then begin try @SMTP := GetProcAddress(MAPIModule, 'MAPISendMail'); if @SMTP <> nil then Result := SMTP(0, Application.Handle, Msg, 0, 0) = SUCCESS_SUCCESS; finally FreeLibrary(MAPIModule); end; end; end; end. When i click the Button1, it will prompt the confirmation dialog as print screen. My question is how to immediate send mail without prompt the confirmation dialog? Is this possible to achieve?

    Read the article

  • Can I call make runtime decided method calls in Java?

    - by Catalin Marin
    I know there is an invoke function that does the stuff, I am overall interested in the "correctness" of using such a behavior. My issue is this: I have a Service Object witch contains methods which I consider services. What I want to do is alter the behavior of those services without later intrusion. For example: class MyService { public ServiceResponse ServeMeDonuts() { do stuff... return new ServiceResponse(); } after 2 months I find out that I need to offer the same service to a new client app and I also need to do certain extra stuff like setting a flag, or make or updating certain data, or encode the response differently. What I can do is pop it up and throw down some IFs. In my opinion this is not good as it means interaction with tested code and may result in un wanted behaviour for the previous service clients. So I come and add something to my registry telling the system that the "NewClient" has a different behavior. So I'll do something like this: public interface Behavior { public void preExecute(); public void postExecute(); } public class BehaviorOfMyService implements Behavior{ String method; String clientType; public void BehaviorOfMyService(String method,String clientType) { this.method = method; this.clientType = clientType; } public void preExecute() { Method preCall = this.getClass().getMethod("pre" + this.method + this.clientType); if(preCall != null) { return preCall.invoke(); } return false; } ...same for postExecute(); public void preServeMeDonutsNewClient() { do the stuff... } } when the system will do something like this if(registrySaysThereIs different behavior set for this ServiceObject) { Class toBeCalled = Class.forName("BehaviorOf" + usedServiceObjectName); Object instance = toBeCalled.getConstructor().newInstance(method,client); instance.preExecute(); ....call the service... instance.postExecute(); .... } I am not particularly interested in correctness of code as in correctness of thinking and approach. Actually I have to do this in PHP, witch I see as a kind of Pop music of programming which I have to "sing" for commercial reasons, even though I play POP I really want to sing by the book, so putting aside my more or less inspired analogy I really want to know your opinion on this matter for it's practical necessity and technical approach. Thanks

    Read the article

  • Getting a seg fault, having trouble with classes and variables.

    - by celestialorb
    Ok, so I'm still learning the ropes of C++ here so I apologize if this is a simple mistake. I have this class: class RunFrame : public wxFrame { public: RunFrame(); void OnKey(wxKeyEvent& keyEvent); private: // Configuration variables. const wxString *title; const wxPoint *origin; const wxSize *size; const wxColour *background; const wxColour *foreground; const wxString *placeholder; // Control variables. wxTextCtrl *command; // Event table. DECLARE_EVENT_TABLE() }; ...then in the OnKey method I have this code: void RunFrame::OnKey(wxKeyEvent& keyEvent) { // Take the key and process it. if(WXK_RETURN == keyEvent.GetKeyCode()) { bool empty = command -> IsEmpty(); } // Propogate the event through. keyEvent.Skip(); } ...but my program keeps seg faulting when it reaches the line where I attempt to call the IsEmpty method from the command variable. My question is, "Why?" In the constructor of the RunFrame class I can seemingly call methods for the command variable in the same way I'm doing so in the OnKey method...and it compiles correctly, it just seg faults on me when it attempts to execute that line. Here is the code for the constructor if necessary: RunFrame::RunFrame() : wxFrame(NULL, wxID_ANY, wxT("DEFAULT"), wxDefaultPosition, wxDefaultSize, wxBORDER_NONE) { // Create the styling constants. title = new wxString(wxT("RUN")); origin = new wxPoint(0, 0); size = new wxSize(250, 25); background = new wxColour(33, 33, 33); foreground = new wxColour(255, 255, 255); placeholder = new wxString(wxT("command")); // Set the styling for the frame. this -> SetTitle(*title); this -> SetSize(*size); // Create the panel and attach the TextControl to it. wxPanel *panel = new wxPanel(this, wxID_ANY, *origin, *size, wxBORDER_NONE); // Create the text control and attach it to the panel. command = new wxTextCtrl(panel, wxID_ANY, *placeholder, *origin, *size); // Set the styling for the text control. command -> SetBackgroundColour(*background); command -> SetForegroundColour(*foreground); // Connect the key event to the text control. command -> Connect(wxEVT_CHAR, wxKeyEventHandler(RunFrame::OnKey)); // Set the focus to the command box. command -> SetFocus(); } Thanks in advance for any help you can give! Regards, celestialorb

    Read the article

  • map<string, vector<string>> reassignment of vector value

    - by user2950936
    I am trying to write a program that takes lines from an input file, sorts the lines into 'signatures' for the purpose of combining all words that are anagrams of each other. I have to use a map, storing the 'signatures' as the keys and storing all words that match those signatures into a vector of strings. Afterwards I must print all words that are anagrams of each other on the same line. Here is what I have so far: #include <iostream> #include <string> #include <algorithm> #include <map> #include <fstream> using namespace std; string signature(const string&); void printMap(const map<string, vector<string>>&); int main(){ string w1,sig1; vector<string> data; map<string, vector<string>> anagrams; map<string, vector<string>>::iterator it; ifstream myfile; myfile.open("words.txt"); while(getline(myfile, w1)) { sig1=signature(w1); anagrams[sig1]=data.push_back(w1); //to my understanding this should always work, } //either by inserting a new element/key or //by pushing back the new word into the vector<string> data //variable at index sig1, being told that the assignment operator //cannot be used in this way with these data types myfile.close(); printMap(anagrams); return 0; } string signature(const string& w) { string sig; sig=sort(w.begin(), w.end()); return sig; } void printMap(const map& m) { for(string s : m) { for(int i=0;i<m->second.size();i++) cout << m->second.at(); cout << endl; } } The first explanation is working, didn't know it was that simple! However now my print function is giving me: prob2.cc: In function âvoid printMap(const std::map<std::basic_string<char>, std::vector<std::basic_string<char> > >&)â: prob2.cc:43:36: error: cannot bind âstd::basic_ostream<char>::__ostream_type {aka std::basic_ostream<char>}â lvalue to âstd::basic_ostream<char>&&â In file included from /opt/centos/devtoolset-1.1/root/usr/lib/gcc/x86_64-redhat-linux/4.7.2/../../../../include/c++/4.7.2/iostream:40:0, Tried many variations and they always complain about binding void printMap(const map<string, vector<string>> &mymap) { for(auto &c : mymap) cout << c.first << endl << c.second << endl; }

    Read the article

  • Make file Linking issue Undefined symbols for architecture x86_64

    - by user1035839
    I am working on getting a few files to link together using my make file and c++ and am getting the following error when running make. g++ -bind_at_load `pkg-config --cflags opencv` -c -o compute_gist.o compute_gist.cpp g++ -bind_at_load `pkg-config --cflags opencv` -c -o gist.o gist.cpp g++ -bind_at_load `pkg-config --cflags opencv` -c -o standalone_image.o standalone_image.cpp g++ -bind_at_load `pkg-config --cflags opencv` -c -o IplImageConverter.o IplImageConverter.cpp g++ -bind_at_load `pkg-config --cflags opencv` -c -o GistCalculator.o GistCalculator.cpp g++ -bind_at_load `pkg-config --cflags opencv` `pkg-config --libs opencv` compute_gist.o gist.o standalone_image.o IplImageConverter.o GistCalculator.o -o rungist Undefined symbols for architecture x86_64: "color_gist_scaletab(color_image_t*, int, int, int const*)", referenced from: _main in compute_gist.o ld: symbol(s) not found for architecture x86_64 collect2: ld returned 1 exit status make: *** [rungist] Error 1 My makefile is as follows (Note, I don't need opencv bindings yet, but will be coding in opencv later. CXX = g++ CXXFLAGS = -bind_at_load `pkg-config --cflags opencv` LFLAGS = `pkg-config --libs opencv` SRC = \ compute_gist.cpp \ gist.cpp \ standalone_image.cpp \ IplImageConverter.cpp \ GistCalculator.cpp OBJS = $(SRC:.cpp=.o) rungist: $(OBJS) $(CXX) $(CXXFLAGS) $(LFLAGS) $(OBJS) -o $@ all: rungist clean: rm -rf $(OBJS) rungist The method header is located in gist.h float *color_gist_scaletab(color_image_t *src, int nblocks, int n_scale, const int *n_orientations); And the method is defined in gist.cpp float *color_gist_scaletab(color_image_t *src, int w, int n_scale, const int *n_orientation) { And finally the compute_gist.cpp (main file) #include <stdio.h> #include <stdlib.h> #include <string.h> #include "gist.h" static color_image_t *load_ppm(const char *fname) { FILE *f=fopen(fname,"r"); if(!f) { perror("could not open infile"); exit(1); } int width,height,maxval; if(fscanf(f,"P6 %d %d %d",&width,&height,&maxval)!=3 || maxval!=255) { fprintf(stderr,"Error: input not a raw PPM with maxval 255\n"); exit(1); } fgetc(f); /* eat the newline */ color_image_t *im=color_image_new(width,height); int i; for(i=0;i<width*height;i++) { im->c1[i]=fgetc(f); im->c2[i]=fgetc(f); im->c3[i]=fgetc(f); } fclose(f); return im; } static void usage(void) { fprintf(stderr,"compute_gist options... [infilename]\n" "infile is a PPM raw file\n" "options:\n" "[-nblocks nb] use a grid of nb*nb cells (default 4)\n" "[-orientationsPerScale o_1,..,o_n] use n scales and compute o_i orientations for scale i\n" ); exit(1); } int main(int argc,char **args) { const char *infilename="/dev/stdin"; int nblocks=4; int n_scale=3; int orientations_per_scale[50]={8,8,4}; while(*++args) { const char *a=*args; if(!strcmp(a,"-h")) usage(); else if(!strcmp(a,"-nblocks")) { if(!sscanf(*++args,"%d",&nblocks)) { fprintf(stderr,"could not parse %s argument",a); usage(); } } else if(!strcmp(a,"-orientationsPerScale")) { char *c; n_scale=0; for(c=strtok(*++args,",");c;c=strtok(NULL,",")) { if(!sscanf(c,"%d",&orientations_per_scale[n_scale++])) { fprintf(stderr,"could not parse %s argument",a); usage(); } } } else { infilename=a; } } color_image_t *im=load_ppm(infilename); //Here's the method call -> :( float *desc=color_gist_scaletab(im,nblocks,n_scale,orientations_per_scale); int i; int descsize=0; //compute descriptor size for(i=0;i<n_scale;i++) descsize+=nblocks*nblocks*orientations_per_scale[i]; descsize*=3; // color //print descriptor for(i=0;i<descsize;i++) printf("%.4f ",desc[i]); printf("\n"); free(desc); color_image_delete(im); return 0; } Any help would be greatly appreciated. I hope this is enough info. Let me know if I need to add more.

    Read the article

  • Why is my NSURLConnection so slow?

    - by Bama91
    I have setup an NSURLConnection using the guidelines in Using NSURLConnection from the Mac OS X Reference Library, creating an NSMutableURLRequest as POST to a PHP script with a custom body to upload 20 MB of data (see code below). Note that the post body is what it is (line breaks and all) to exactly match an existing desktop implementation. When I run this in the iPhone simulator, the post is successful, but takes an order of magnitude longer than if I run the equivalent code locally on my Mac in C++ (20 minutes vs. 20 seconds, respectively). Any ideas why the difference is so dramatic? I understand that the simulator will give different results than the actual device, but I would expect at least similar results. Thanks const NSUInteger kDataSizePOST = 20971520; const NSString* kServerBDC = @"WWW.SOMEURL.COM"; const NSString* kUploadURL = @"http://WWW.SOMEURL.COM/php/test/upload.php"; const NSString* kUploadFilename = @"test.data"; const NSString* kUsername = @"testuser"; const NSString* kHostname = @"testhost"; srandom(time(NULL)); NSMutableData *uniqueData = [[NSMutableData alloc] initWithCapacity:kDataSizePOST]; for (unsigned int i = 0 ; i < kDataSizePOST ; ++i) { u_int32_t randomByte = ((random() % 95) + 32); [uniqueData appendBytes:(void*)&randomByte length:1]; } NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init]; [request setURL:[NSURL URLWithString:kUploadURL]]; [request setHTTPMethod:@"POST"]; NSString *boundary = @"aBcDd"; NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary]; [request addValue:contentType forHTTPHeaderField: @"Content-Type"]; NSMutableData *postbody = [NSMutableData data]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[uniqueData length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: form-data; name=test; filename=%@", kUploadFilename] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithString:@";\nContent-Type: multipart/mixed;\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[NSData dataWithData:uniqueData]]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[kUsername length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: inline; name=Username;\n\r\n%@",kUsername] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"--%@\nContent-Size:%d",boundary,[kHostname length]] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\nContent-Disposition: inline; name=Hostname;\n\r\n%@",kHostname] dataUsingEncoding:NSUTF8StringEncoding]]; [postbody appendData:[[NSString stringWithFormat:@"\n--%@--",boundary] dataUsingEncoding:NSUTF8StringEncoding]]; [request setHTTPBody:postbody]; NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self]; if (theConnection) { _receivedData = [[NSMutableData data] retain]; } else { // Inform the user that the connection failed. } [request release]; [uniqueData release];

    Read the article

  • How to safely operate on parameters in threads, using C++ & Pthreads?

    - by ChrisCphDK
    Hi. I'm having some trouble with a program using pthreads, where occassional crashes occur, that could be related to how the threads operate on data So I have some basic questions about how to program using threads, and memory layout: Assume that a public class function performs some operations on some strings, and returns the result as a string. The prototype of the function could be like this: std::string SomeClass::somefunc(const std::string &strOne, const std::string &strTwo) { //Error checking of strings have been omitted std::string result = strOne.substr(0,5) + strTwo.substr(0,5); return result; } Is it correct to assume that strings, being dynamic, are stored on the heap, but that a reference to the string is allocated on the stack at runtime? Stack: [Some mem addr] pointer address to where the string is on the heap Heap: [Some mem addr] memory allocated for the initial string which may grow or shrink To make the function thread safe, the function is extended with the following mutex (which is declared as private in the "SomeClass") locking: std::string SomeClass::somefunc(const std::string &strOne, const std::string &strTwo) { pthread_mutex_lock(&someclasslock); //Error checking of strings have been omitted std::string result = strOne.substr(0,5) + strTwo.substr(0,5); pthread_mutex_unlock(&someclasslock); return result; } Is this a safe way of locking down the operations being done on the strings (all three), or could a thread be stopped by the scheduler in the following cases, which I'd assume would mess up the intended logic: a. Right after the function is called, and the parameters: strOne & strTwo have been set in the two reference pointers that the function has on the stack, the scheduler takes away processing time for the thread and lets a new thread in, which overwrites the reference pointers to the function, which then again gets stopped by the scheduler, letting the first thread back in? b. Can the same occur with the "result" string: the first string builds the result, unlocks the mutex, but before returning the scheduler lets in another thread which performs all of it's work, overwriting the result etc. Or are the reference parameters / result string being pushed onto the stack while another thread is doing performing it's task? Is the safe / correct way of doing this in threads, and "returning" a result, to pass a reference to a string that will be filled with the result instead: void SomeClass::somefunc(const std::string &strOne, const std::string &strTwo, std::string result) { pthread_mutex_lock(&someclasslock); //Error checking of strings have been omitted result = strOne.substr(0,5) + strTwo.substr(0,5); pthread_mutex_unlock(&someclasslock); } The intended logic is that several objects of the "SomeClass" class creates new threads and passes objects of themselves as parameters, and then calls the function: "someFunc": int SomeClass::startNewThread() { pthread_attr_t attr; pthread_t pThreadID; if(pthread_attr_init(&attr) != 0) return -1; if(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0) return -2; if(pthread_create(&pThreadID, &attr, proxyThreadFunc, this) != 0) return -3; if(pthread_attr_destroy(&attr) != 0) return -4; return 0; } void* proxyThreadFunc(void* someClassObjPtr) { return static_cast<SomeClass*> (someClassObjPtr)->somefunc("long string","long string"); } Sorry for the long description. But I hope the questions and intended purpose is clear, if not let me know and I'll elaborate. Best regards. Chris

    Read the article

  • What is wrong with my specular phong shading

    - by Thijser
    I'm sorry if this should be placed on stackoverflow instead however seeing as this is graphics related I was hoping you guys could help me: I'm attempting to write a phong shader and currently working on the specular. I came acros the following formula: base*pow(dot(V,R),shininess) and attempted to implement it (V is the posion of the viewer and R the reflective vector). This gave the following result and code: Vec3Df phongSpecular(const Vec3Df & vertexPos, Vec3Df & normal, const Vec3Df & lightPos, const Vec3Df & cameraPos, unsigned int index) { Vec3Df relativeLightPos=(lightPos-vertexPos); relativeLightPos.normalize(); Vec3Df relativeCameraPos= (cameraPos-vertexPos); relativeCameraPos.normalize(); int DotOfNormalAndLight = Vec3Df::dotProduct(normal,relativeLightPos); Vec3Df reflective =(relativeLightPos-(2*DotOfNormalAndLight*normal))*-1; reflective.normalize(); float phongyness= Vec3Df::dotProduct(reflective,relativeCameraPos); if (phongyness<0){ phongyness=0; } float shininess= Shininess[index]; float speculair = powf(phongyness,shininess); return Ks[index]*speculair; } I'm looking for something more like this:

    Read the article

  • When does the "Do One Thing" paradigm become harmful?

    - by Petr
    For the sake of argument here's a sample function that prints contents of a given file line-by-line. Version 1: void printFile(const string & filePath) { fstream file(filePath, ios::in); string line; while (file.good()) { getline(file, line); cout << line << endl; } } I know it is recommended that functions do one thing at one level of abstraction. To me, though code above does pretty much one thing and is fairly atomic. Some books (such as Robert C. Martin's Clean Code) seem to suggest breaking the above code into separate functions. Version 2: void printLine(const string & line) { cout << line << endl; } void printLines(fstream & file) { string line; while (file.good()) { getline(file, line); printLine(line); } } void printFile(const string & filePath) { fstream file(filePath, ios::in); printLines(file); } I understand what they want to achieve (open file / read lines / print line), but isn't it a bit of overkill? The original version is simple and in some sense already does one thing - prints a file. The second version will lead to a large number of really small functions which may be far less legible than the first version. Wouldn't it be, in this case, better to have the code at one place? At which point does the "Do One Thing" paradigm become harmful?

    Read the article

  • Ways to organize interface and implementation in C++

    - by Felix Dombek
    I've seen that there are several different paradigms in C++ concerning what goes into the header file and what to the cpp file. AFAIK, most people, especially those from a C background, do: foo.h class foo { private: int mem; int bar(); public: foo(); foo(const foo&); foo& operator=(foo); ~foo(); } foo.cpp #include foo.h foo::bar() { return mem; } foo::foo() { mem = 42; } foo::foo(const foo& f) { mem = f.mem; } foo::operator=(foo f) { mem = f.mem; } foo::~foo() {} int main(int argc, char *argv[]) { foo f; } However, my lecturers usually teach C++ to beginners like this: foo.h class foo { private: int mem; int bar() { return mem; } public: foo() { mem = 42; } foo(const foo& f) { mem = f.mem; } foo& operator=(foo f) { mem = f.mem; } ~foo() {} } foo.cpp #include foo.h int main(int argc, char* argv[]) { foo f; } // other global helper functions, DLL exports, and whatnot Originally coming from Java, I have also always stuck to this second way for several reasons, such as that I only have to change something in one place if the interface or method names change, and that I like the different indentation of things in classes when I look at their implementation, and that I find names more readable as foo compared to foo::foo. I want to collect pro's and con's for either way. Maybe there are even still other ways? One disadvantage of my way is of course the need for occasional forward declarations.

    Read the article

  • Creating user UI using Flixel

    - by Jamie Read
    I am new to game development but familiar with programming languages. I have started using Flixel and have a working Breakout game with score and lives. What I am trying to do is add a Start Screen before actually loading the game. I have a create function that adds all the game elements to the stage: override public function create():void // all game elements { How can I add this pre-load Start Screen? I'm not sure if I have to add in the code to this create function or somewhere else and what code to actually add. Eventually I would also like to add saving, loading, options and upgrades too. So any advice with that would be great. Here is my main game.as: package { import org.flixel.*; public class Game extends FlxGame { private const resolution:FlxPoint = new FlxPoint(640, 480); private const zoom:uint = 2; private const fps:uint = 60; public function Game() { super(resolution.x / zoom, resolution.y / zoom, PlayState, zoom); FlxG.flashFramerate = fps; } } } Thanks.

    Read the article

  • Why does glGetString returns a NULL string

    - by snape
    I am trying my hands at GLFW library. I have written a basic program to get OpenGL renderer and vendor string. Here is the code #include <GL/glew.h> #include <GL/glfw.h> #include <cstdio> #include <cstdlib> #include <string> using namespace std; void shutDown(int returnCode) { printf("There was an error in running the code with error %d\n",returnCode); GLenum res = glGetError(); const GLubyte *errString = gluErrorString(res); printf("Error is %s\n", errString); glfwTerminate(); exit(returnCode); } int main() { // start GL context and O/S window using GLFW helper library if (glfwInit() != GL_TRUE) shutDown(1); if (glfwOpenWindow(0, 0, 0, 0, 0, 0, 0, 0, GLFW_WINDOW) != GL_TRUE) shutDown(2); // start GLEW extension handler glewInit(); // get version info const GLubyte* renderer = glGetString (GL_RENDERER); // get renderer string const GLubyte* version = glGetString (GL_VERSION); // version as a string printf("Renderer: %s\n", renderer); printf("OpenGL version supported %s\n", version); // close GL context and any other GLFW resources glfwTerminate(); return 0; } I googled this error and found out that we have to initialize the OpenGL context before calling glGetString(). Although I have initialized OpenGL context using glfwInit() but still the function returns a NULL string. Any ideas? Edit I have updated the code with error checking mechanisms. This code on running outputs the following There was an error in running the code with error 2 Error is no error

    Read the article

  • Why can't I create direct3d objects?

    - by quakkels
    I've been programming professionally for years using languages like VBScript, JavaScript, and C#. As a hobby, I'm getting into some c/c++ and games programming with DirectX. I am running into an issue where I cannot create direct3d objects. I am using Visual C++ 2010 Express. After I installed vc++2010express I then installed the June 2010 release of DirectX. I am trying to include DirectX via #pragma statements. This is the code I have so far in my winmain.cpp source file: #include <Windows.h> #include <d3d11.h> #include <time.h> #include <iostream> using namespace std; #pragma comment(lib, "d3d11.lib") #pragma comment(lib, "d3dx11.lib") // program settings const string AppTitle = "Direct3D in a Window"; const int ScreenWidth = 1024; const int ScreenHeight = 768; // direct3d objects LPDIRECT3D11 d3d = NULL; // this line is showing an error The type LPDIRECT3D11 is showing an error: Error: Identifier "LPDIRECT3D11" is undefined Am I missing something here to get VC++2010Express to recognize and load the DirectX libs? Thanks for any help.

    Read the article

  • Variables in static library are never initialized. Why?

    - by Coyote
    I have a bunch of variables that should be initialized then my game launches, but must of them are never initialized. Here is an example of the code: MyClass.h class MyClass : public BaseObject { DECLARE_CLASS_RTTI(MyClass, BaseObject); ... }; MyClass.cpp REGISTER_CLASS(MyClass) Where REGISTER_CLASS is a macro defined as follow #define REGISTER_CLASS(className)\ class __registryItem##className : public __registryItemBase {\ virtual className* Alloc(){ return NEW className(); }\ virtual BaseObject::RTTI& GetRTTI(){ return className::RTTI; }\ }\ \ const __registryItem##className __registeredItem##className(#className); and __registryItemBase looks like this: class __registryItemBase { __registryItemBase(const _string name):mName(name){ ClassRegistry::Register(this); } const _string mName; virtual BaseObject* Alloc() = 0; virtual BaseObject::RTTI& GetRTTI() = 0; } Now the code is similar to what I currently have and what I have works flawlessly, all the registered classes are registered to a ClassManager before main(...) is called. I'm able to instantiate and configure components from scripts and auto-register them to the right system etc... The problem arrises when I create a static library (currently for the iPhone, but I fear it will happen with android as well). In that case the code in the .cpp files is never registered. Why is the resulting code not executed when it is in the library while the same code in the program's binary is always executed? Bonus questions: For this to work in the static library, what should I do? Is there something I am missing? Do I need to pass a flag when building the lib? Should I create another structure and init all the __registeredItem##className using that structure?

    Read the article

< Previous Page | 28 29 30 31 32 33 34 35 36 37 38 39  | Next Page >