Search Results

Search found 7916 results on 317 pages for 'learning sam'.

Page 297/317 | < Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >

  • popViewControllerAnimated not working, but back button works

    - by Manu
    Hi, I am creating an application based on the Utility template. The main screen consists of a menu with several buttons, each of which creates a different flip-side view. In one of those flip-side views I also configured a Navigation Controller, which works perfectly as long as I have the NavigationBar activated... I can push the view but I have to use the "back" button to return to my flip-side view, which would be the root of the Navigation Controller. The problem comes if I try to go back using "popViewControllerAnimated", properly configured with a button, instead of the "back" button of the NavigationBar. My application crashes for some reason and I am not able to understand why. I could just use the "back" button in the NavigationBar and forget about the problem, but I would prefer to have my own button in order to go back. My app consists of the following: My APPDelegate.m: - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { MenuViewController *menuController = [[MenuViewController alloc] initWithNibName:@"MenuView" bundle:nil]; self.menuViewController = menuController; [menuController release]; menuViewController.view.frame = [UIScreen mainScreen].applicationFrame; [window addSubview:[menuViewController view]]; [window makeKeyAndVisible]; return YES; } MenuViewController.m starting my flip-side view: - (IBAction)showFuelUpliftView { FuelUpliftViewController *controller = [[FuelUpliftViewController alloc] initWithNibName:@"FuelUpliftView" bundle:nil]; controller.delegate = self; controller.title = @"Fuel Uplift"; UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:controller]; [navController setNavigationBarHidden: NO]; navController.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal; [self presentModalViewController:navController animated:YES]; [navController release]; [controller release]; } FuelUpliftViewController.m, where I push the second view of the NavigationController with a button: - (IBAction)showFuelUplift2View:(id)sender { UIViewController *controller = [[UIViewController alloc] initWithNibName:@"FuelUplift2View" bundle:nil]; controller.title = @"Settings"; [self.navigationController pushViewController:controller animated:YES]; [controller release]; } And finally, my FuelUplift2ViewController.m, where the app crashes when trying to go back: - (IBAction)backFromFuelUplift2View { [self.navigationController popViewControllerAnimated:YES]; } I do not know if all this makes sense, I am currently beginning with my first application and am still learning thanks to the traditional trial an error method. Nevertheless, I cannot see the reason for this problem and would appreciate any help I can get. Thanks very much, Manu

    Read the article

  • Revisiting .NET, but what should I focus on?

    - by Wayne M
    After about a two-year hiatus, I'm brushing up on my .NET skills to find a .NET job (my previous two positions have very little development, or development using legacy technologies, so apart from a few very minor apps I have not touched .NET in close to two years). I'm aware of things like ASP.NET MVC, and I have previously read on things like NHibernate and DI/IOC, albeit I have yet to use them apart from very trivial "Hello World" type applications. I have a subscription to Rob Conery's Tekpub website and occasionally watch these videos when I have free time. My concern is this: I don't live in a very technical area. I would be surprised if any but the most tech-savvy companies have heard of, let alone use, ASP.NET MVC, NHibernate (or even LINQ/EF), or know about IoC. I would be willing to bet a large sum of money that 95% of the possible jobs I could obtain will use the following: Visual Source Safe, if any VCS at all ASP.NET 2.0 Webforms (3.5 if lucky) Raw ADO.NET on top of a very thin implementation of the Gateway pattern Stored Procedures in the database for most CRUD operations Gratuitous use of code-behind, with a Service layer if I'm lucky If I were extremely lucky, I might find a shop that has heard of ORMs and either uses one, or has wrote their own data abstraction. Also if I were lucky, the company would be using Model-View-Presenter. In light of this I'm not sure what I should focus on learning. Personally, I would prefer to be using the latest stuff - ASP.NET MVC, NHibernate, jQuery, WCF etc. Reality says I should go back to the basics, since it looks like most potential opportunities aren't going to be anywhere near the cutting edge, or anywhere close to it. And, as much as I would like to find a position and start to show the other developers the benefits, in my past experience this has usually resulted in my being fired for "not being a team player" and doing things the bad old way. So, I am curious how you would approach a situation like this? What should I focus on, in order to A) Reaquaint myself with .NET, and B) Prepare myself to obtain a .NET job again that is more than likely going to use techniques that I and most other knowledgeable developers will scoff at?

    Read the article

  • Best programming aids for a quadriplegic programmer

    - by Peter Rowell
    Before you jump to conclusions, yes, this is programming related. It covers a situation that comes under the heading of, "There, but for the grace of God, go you or I." This is brand new territory for me so I'm asking for some serious help here. A young man, Honza Ripa, in a nearby town did the classic Dumb Thing two weeks after graduating from High School -- he dove into shallow water in the Russian River and had a C-4/C-5 break, sometimes called a Swimming Pool break. In a matter of seconds he went from an exceptional golfer and wrestler to a quadriplegic. (Read the story ... all of us should have been so lucky as to have a girlfriend like Brianna.) That was 10 months ago and he has regained only tiny amounts of control of his right index finger and a couple of other hand/foot motions, none of them fine-grained. His total control of his computer (currently running Win7, but we can change that as needed) is via voice command. Honza's not dumb. He had a 3.7 GPA with AP math and physics. The Problems: Since all of his input is via voice command, he is concerned that the predominance of special characters in programming will require vast amount of verbose commands. Does anyone know of any well done voice input system specifically designed for programmers? I'm thinking about something that might be modal--e.g. you say "Python input" and it goes into a macro mode for doing class definitions, etc. Given all of the RSI in programmer-land there's got to be something out there. What OS(es) does it run on? I am planning on teaching him Python, which is my preferred language for programming and teaching. Are there any applications / whatevers that are written in Python and would be a particularly good match for engaging him mentally while supporting his disability? One of his expressed interests is in stock investing, but that not might be a good starting point for a brand-new programmer. There are a lot of environments (Flash, JavaScript, etc) that are not particularly friendly to people with accessibility challenges. I vaguely remember (but cannot find) a research project that basically created an overlay system on top of a screen environment and then allowed macro command construction on top of the screen image. If we can get/train this system, we may be able to remove many hurdles to using the net. I am particularly interested in finding open source Python-based robotics and robotic prostheses projects so that he can simultaneously learn advanced programming concepts while learning to solve some of his own immediate problems. I've done a ton of googling on this, but I know there things I'm missing. I'm asking the SO community to step up to the plate here. I know this group has the answers, so let me hear them! Overwhelm me with the opportunities that any of us might have/need to still program after such a life-changing event.

    Read the article

  • sudo apt-get install python.pip python-dev Gives Error

    - by user2539745
    I am learning Django from http://gettingstartedwithdjango.com/ and I have windows 7 32-bit. The tutorial asked to install virtualbox and vagrant(tutorial had precise64 and it had issues in my pc so I installed precise32) so I did it. Now the tutorial asked to do sudo apt-get install python-dev python.pip so I did it but it gave me this error > vagrant@precise32:~$ sudo apt-get install python.pip python-dev Reading package lists... Done Building dependency tree Reading state information... Done Note, selecting 'python-pip' for regex 'python.pip' Note, selecting 'python-pipeline' for regex 'python.pip' The following extra packages will be installed: libexpat1 libexpat1-dev libpython2.7 python-pkg-resources python-setuptools python-support python2.7 python2.7-dev python2.7-minimal Suggested packages: python-distribute python-distribute-doc python2.7-doc binfmt-support The following NEW packages will be installed: libexpat1-dev libpython2.7 python-dev python-pip python-pipeline python-pkg-resources python-setuptools python-support python2.7-dev The following packages will be upgraded: libexpat1 python2.7 python2.7-minimal 3 upgraded, 9 newly installed, 0 to remove and 63 not upgraded. Need to get 34.7 MB/35.7 MB of archives. After this operation, 42.0 MB of additional disk space will be used. Do you want to continue [Y/n]? y Err (http removed)us.archive.ubuntu.com/ubuntu/ precise-updates/main python2.7 i386 2.7 .3-0ubuntu3.1 404 Not Found [IP: 91.189.91.15 80] Err (http removed)us.archive.ubuntu.com/ubuntu/ precise-updates/main python2.7-minimal i386 2.7.3-0ubuntu3.1 404 Not Found [IP: 91.189.91.15 80] Err (http removed)us.archive.ubuntu.com/ubuntu/ precise-updates/main libpython2.7 i386 2.7.3-0ubuntu3.1 404 Not Found [IP: 91.189.91.15 80] Err (http removed)us.archive.ubuntu.com/ubuntu/ precise-updates/main python2.7-dev i386 2.7.3-0ubuntu3.1 404 Not Found [IP: 91.189.91.15 80] Failed to fetch (http removed)us.archive.ubuntu.com/ubuntu/pool/main/p/python2.7/python 2.7_2.7.3-0ubuntu3.1_i386.deb 404 Not Found [IP: 91.189.91.15 80] Failed to fetch (http removed)us.archive.ubuntu.com/ubuntu/pool/main/p/python2.7/python 2.7-minimal_2.7.3-0ubuntu3.1_i386.deb 404 Not Found [IP: 91.189.91.15 80] Failed to fetch (http removed)us.archive.ubuntu.com/ubuntu/pool/main/p/python2.7/libpyt hon2.7_2.7.3-0ubuntu3.1_i386.deb 404 Not Found [IP: 91.189.91.15 80] Failed to fetch (http removed)us.archive.ubuntu.com/ubuntu/pool/main/p/python2.7/python 2.7-dev_2.7.3-0ubuntu3.1_i386.deb 404 Not Found [IP: 91.189.91.15 80] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-mis sing? Please help what should I do ??

    Read the article

  • Using GraphicsServices.h/GSEvent as well as compiling CLI iPhone tools with XCode

    - by Peter Hajas
    I sent this to KennyTM (has all the private framework headers on GitHub) but I figured I'd ask here too just in case someone has some good ideas or any way to help me out. I'm trying to write a command line utility that sends GSEvents to operate the keyboard, touch/drag elements onscreen, and operate hardware buttons (volume, home, sleep, etc.) I grabbed the MouseSupport code and tried to look through it, but I couldn't find the easiest way to send GSEvents. I'm hoping someone here can help me. First, what's the simplest way to declare a GSEvent and send it? I looked at the iPhone development wiki, but the documentation was very vague. I understand that there's a purple event port (?) that I have to send these events to, but I don't understand how to do that. Could someone offer examples for, say, touching at a coordinate, typing a certain key, or pressing a hardware button? Also, do I have to write or do anything special if I want this utility to operate all applications as well as Springboard? I don't know if this is a special case because I want it at the OS level. Ideally, I would SSH into the phone, start the program, and it would send GSEvents that would be handled by whatever application was open. As far as compiling this code, is there any way to do so under XCode? I don't know what sort of project template I should use (if any) and this is throwing me off. I don't need "build and go" support, I'm more than happy to scp the program over to the phone. I understand that compiling the code is also feasible on the phone. I have all of the headers from the SDK on my phone along with iphone-gcc, but when compiling some test programs I still get errors about not finding mach headers and CoreFoundation. Is there an easier way to do this? Lastly, are there other guides or pieces of literature that anyone can point me towards for learning more about this? I'm excited to get into open iPhone development (I have experience with the official SDK, but I want to go deeper). Thanks for any and all help people can offer!

    Read the article

  • Question About Example In Robert C Martin's _Clean Code_

    - by Jonah
    This is a question about the concept of a function doing only one thing. It won't make sense without some relevant passages for context, so I'll quote them here. They appear on pgs 37-38: To say this differently, we want to be able to read the program as though it were a set of TO paragraphs, each of which is describing the current level of abstraction and referencing subsequent TO paragraphs at the next level down. To include the setups and teardowns, we include setups, then we include the test page content, and then we include the teardowns. To include the setups, we include the suite setup if this is a suite, then we include the regular setup. It turns out to be very dif?cult for programmers to learn to follow this rule and write functions that stay at a single level of abstraction. But learning this trick is also very important. It is the key to keeping functions short and making sure they do “one thing.” Making the code read like a top-down set of TO paragraphs is an effective technique for keeping the abstraction level consistent. He then gives the following example of poor code: public Money calculatePay(Employee e) throws InvalidEmployeeType { switch (e.type) { case COMMISSIONED: return calculateCommissionedPay(e); case HOURLY: return calculateHourlyPay(e); case SALARIED: return calculateSalariedPay(e); default: throw new InvalidEmployeeType(e.type); } } and explains the problems with it as follows: There are several problems with this function. First, it’s large, and when new employee types are added, it will grow. Second, it very clearly does more than one thing. Third, it violates the Single Responsibility Principle7 (SRP) because there is more than one reason for it to change. Fourth, it violates the Open Closed Principle8 (OCP) because it must change whenever new types are added. Now my questions. To begin, it's clear to me how it violates the OCP, and it's clear to me that this alone makes it poor design. However, I am trying to understand each principle, and it's not clear to me how SRP applies. Specifically, the only reason I can imagine for this method to change is the addition of new employee types. There is only one "axis of change." If details of the calculation needed to change, this would only affect the submethods like "calculateHourlyPay()" Also, while in one sense it is obviously doing 3 things, those three things are all at the same level of abstraction, and can all be put into a TO paragraph no different from the example one: TO calculate pay for an employee, we calculate commissioned pay if the employee is commissioned, hourly pay if he is hourly, etc. So aside from its violation of the OCP, this code seems to conform to Martin's other requirements of clean code, even though he's arguing it does not. Can someone please explain what I am missing? Thanks.

    Read the article

  • Team Foundation Server Setup/Access

    - by Angel Brighteyes
    What I need: A TFS 2010 Setup that allows 2 application developers to access the TFS from remote locations. How it is setup: Server 2008 Standard 2g Ram 300g HD space SharePoint Server 2007, using SQL Server 2005 SQL Server 2008 Standard Team Foundation Server 2010 IIS 7 Sharepoint Bindings: TFS.DynAccount.Me:80; TFS:80 TFS Bindings: TFS.DynAccount.Me:8080; TFS:8080 Using DynDNS service to account for the dynamic ip address being used, this is a requirement for the moment until I can get a better isp package. Access using Local Accounts Server is not setup on a domain, or as a domain. Consequently I did not setup AD services. Problem: When logged into TFS using my credentials TFS\AdminUser through the DynDNS account TFS.DynAccount.Me I recieve the 'Red X of Death' on the Documents and Reports folder. When logged into the TFS through the local peer to peer network using the same credentials TFS\AdminUser I do not receive the 'Red X of Death' problem. Further Troubleshooting: When users 'Right Click' the 'TeamProject1' Click 'Show Project Portal' it tries to take them to http://TFS:8080 instead of http://TFS.DynAccount.Me:8080, which doing further research I am assuming that it is because team foundation server was setup with a local name of TFS instead of 'TFS.DynAccount.Me' as specified here in Visual Studio Magazines: The Red X of Death. Users can Access the Team Portal for SharePoint via http://TFS.DynAccount.Me/TeamCollection/TeamProject so it is not like we are dead in the water or anything. However, as most employees/staff are prone to do, they have expressed a great distaste for having to do it this way and just be patient until the current project is finished since we are under a very strict deadline. Is there a way to set this up differently, or change some settings someplace, reinstall it, point a CName record for our domain website to the DynAccount (e.g. TFS.OurDomain.com points to TFS.DynAccount.Me, which consequently does allow access to the http site without issues), or something. I really don't feel like after all the time and effort I have spent into, first the cost, second the bloody install, third learning SharePoint well enough, fourth the hours into days spent on this, fifth more troubleshooting, sixth employee headaches to just let it lay where it is at. I figure in my spare/off time I would keep trying to get this to work. So I really appreciate any help any one can give me. I know this is probably something really stupid simple that I will 'Face Palm' over, but at the moment the stress and frustration just has me beat. Thank you again, this community has always been a great help.

    Read the article

  • How to arrange models, views, controllers in a Kohana 3 project

    - by Pekka
    I'm looking at how to set up a mid-sized web application with Kohana 3. I have implemented MVC patterns in the past but never worked against a "formalized" MVC framework so I'm still getting my head around the terminology - toying around with basic examples, building views and templates, and so on. I'm progressing fairly well but I want to set up a real-world web project (one of my own that I've been planning for quite some time now) as a learning object. I learn best by example, but example-based documentation is a bit sparse for Kohana 3 right now - they say so themselves on the site. While I'm not worried about getting into the framework soon enough, I'm a bit concerned about arranging a healthily structured code base from the start - i.e. how to split up controllers, how to name them, and how to separate the functionality into the appropriate models. My application could, in its core, be described as a business directory with a main businesses table. Businesses can be listed by category and by street name. Each business has a detail page. Business owners can log in and edit their business's entry. Businesses can post offers into an offers table. I know this is not very detailed, but I don't want to cram too much information into this question. I'll be more than happy to go into more detail if needed. Supposing I have all the basic functionality worked out and in place already - list all businesses, edit business, list businesses by street name, create offer logged in as business, and so on, and I'm just looking for how to fit the functionality into a MVC pattern and into a Kohana application structure that can be easily extended: Do you know real-life, publicly accessible examples of "database-heavy" applications like directories, online communities... with a log-in area built on Kohana 3 where I could take a peek how they do it? Are there conventions or best practices on how to structure an extendable login area for end users in a Kohana project that is not only able to handle a business directory page, but further products on separate pages as well? Do you know application structuring HOWTOs or best practices for Kohana 3 not mentioned in the user guide and the inofficial Wiki? Have you built something similar and could give me some recommendations?

    Read the article

  • WPF Beginner - A simple XAML layout not working as expected

    - by OrWhen
    Hi, I've just started learning WPF, and followed a book to make this sample calculator application in XAML. The XAML code is attached below. I don't have any UI specific code in the xaml.cs file. However, I'm seeing a difference between design time and runtime. As you can see in the attached screenshot, the upper left button of the calculator is bigger than the rest. Even more confusingly, the designer when I edit the XAML shows the button correctly. I've tried to determine why is that, and I'm stumped. Can anyone help? I'm using VS2008, targeting framework 3.5, if it's any help. Here's the XAML: <TextBlock Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="4" FontSize="24" Name="Header" VerticalAlignment="Center" HorizontalAlignment="Center">Calculator</TextBlock> <TextBox Grid.ColumnSpan="4" Grid.Column="0" Grid.Row="1" Name="Display" HorizontalContentAlignment="Left" Margin="5" /> <Button Grid.Row="2" Grid.Column="0" Click="Button_Click">7</Button> <Button Grid.Row="2" Grid.Column="1" Click="Button_Click">8</Button> <Button Grid.Row="2" Grid.Column="2" Click="Button_Click">9</Button> <Button Grid.Row="3" Grid.Column="0" Click="Button_Click">4</Button> <Button Grid.Row="3" Grid.Column="1" Click="Button_Click">5</Button> <Button Grid.Column="2" Grid.Row="3" Click="Button_Click">6</Button> <Button Grid.Row="4" Grid.Column="0" Click="Button_Click">1</Button> <Button Grid.Row="4" Grid.Column="1" Click="Button_Click">2</Button> <Button Grid.Row="4" Grid.Column="2" Click="Button_Click">3</Button> <Button Grid.Row="5" Grid.Column="0" Click="Button_Click">0</Button> <Button Grid.Row="5" Grid.Column="3" Tag="{x:Static local:Operation.PLUS}" Click="Op_Click">+</Button> <Button Grid.Row="4" Grid.Column="3" Tag="{x:Static local:Operation.MINUS}" Click="Op_Click">-</Button> <Button Grid.Row="3" Grid.Column="3" Tag="{x:Static local:Operation.TIMES}" Click="Op_Click">*</Button> <Button Grid.Row="2" Grid.Column="3" Tag="{x:Static local:Operation.DIVIDE}" Click="Op_Click">/</Button> <Button Grid.Row="5" Grid.Column="1" >.</Button> <Button Grid.Row="5" Grid.Column="2" Tag="{x:Static local:Operation.EQUALS}" Click="Op_Click">=</Button> </Grid>

    Read the article

  • Need help implementing simple socket server using GIOService (GLib, Glib-GIO)

    - by Mark Renouf
    I'm learning the basics of writing a simple, efficient socket server using GLib. I'm experimenting with GSocketService. So far I can only seem to accept connections but then they are immediately closed. From the docs I can't figure out what step I am missing. I'm hoping someone can shed some light on this for me. When running the following: # telnet localhost 4000 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host. # telnet localhost 4000 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host. # telnet localhost 4000 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host. Output from the server: # ./server New Connection from 127.0.0.1:36962 New Connection from 127.0.0.1:36963 New Connection from 127.0.0.1:36965 Current code: /* * server.c * * Created on: Mar 10, 2010 * Author: mark */ #include <glib.h> #include <gio/gio.h> gchar *buffer; gboolean network_read(GIOChannel *source, GIOCondition cond, gpointer data) { GString *s = g_string_new(NULL); GError *error; GIOStatus ret = g_io_channel_read_line_string(source, s, NULL, &error); if (ret == G_IO_STATUS_ERROR) g_error ("Error reading: %s\n", error->message); else g_print("Got: %s\n", s->str); } gboolean new_connection(GSocketService *service, GSocketConnection *connection, GObject *source_object, gpointer user_data) { GSocketAddress *sockaddr = g_socket_connection_get_remote_address(connection, NULL); GInetAddress *addr = g_inet_socket_address_get_address(G_INET_SOCKET_ADDRESS(sockaddr)); guint16 port = g_inet_socket_address_get_port(G_INET_SOCKET_ADDRESS(sockaddr)); g_print("New Connection from %s:%d\n", g_inet_address_to_string(addr), port); GSocket *socket = g_socket_connection_get_socket(connection); gint fd = g_socket_get_fd(socket); GIOChannel *channel = g_io_channel_unix_new(fd); g_io_add_watch(channel, G_IO_IN, (GIOFunc) network_read, NULL); return TRUE; } int main(int argc, char **argv) { g_type_init(); GSocketService *service = g_socket_service_new(); GInetAddress *address = g_inet_address_new_from_string("127.0.0.1"); GSocketAddress *socket_address = g_inet_socket_address_new(address, 4000); g_socket_listener_add_address(G_SOCKET_LISTENER(service), socket_address, G_SOCKET_TYPE_STREAM, G_SOCKET_PROTOCOL_TCP, NULL, NULL, NULL); g_object_unref(socket_address); g_object_unref(address); g_socket_service_start(service); g_signal_connect(service, "incoming", G_CALLBACK(new_connection), NULL); GMainLoop *loop = g_main_loop_new(NULL, FALSE); g_main_loop_run(loop); }

    Read the article

  • MySQL create stored procedure fails but all internal queries succeed alone?

    - by Mark
    Hi all, I just created a simple database in MySQL, and I am learning how to write stored proc's. I'm familiar with M$SQL and as far as I can see the following should work: use mydb; -- -------------------------------------------------------------------------------- -- Routine DDL -- -------------------------------------------------------------------------------- DELIMITER // CREATE PROCEDURE mydb.doStats () BEGIN CREATE TABLE IF NOT EXISTS resultprobability ( ballNumber INT NOT NULL , probability FLOAT NULL, PRIMARY KEY (ballNumber) ); CREATE TABLE IF NOT EXISTS drawProbability ( drawDate DATE NOT NULL , ball1 INT NULL , ball2 INT NULL , ball3 INT NULL , ball4 INT NULL , ball5 INT NULL , ball6 INT NULL , ball7 INT NULL , score FLOAT NULL , PRIMARY KEY (drawDate) ); TRUNCATE TABLE resultprobability; TRUNCATE TABLE drawprobability; INSERT INTO resultprobability (ballNumber, probability) (select resultset.ballNumber ballNumber,(count(0)/(select count(0) from resultset)) probability from resultset group by resultset.ballNumber); INSERT INTO drawProbability (drawDate, ball1, ball2, ball3, ball4, ball5, ball6, ball7, score) (select distinct r.drawDate, a.ballnumber ball1, b.ballnumber ball2, c.ballnumber ball3, d.ballnumber ball4, e.ballnumber ball5, f.ballnumber ball6,g.ballnumber ball7, ((a.probability + b.probability + c.probability + d.probability + e.probability + f.probability + g.probability)/7) score from resultset r inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 1) a on a.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 2) b on b.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 3) c on c.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 4) d on d.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 5) e on e.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 6) f on f.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 7) g on g.drawdate = r.drawDate order by score desc); END // DELIMITER ; instead i get the following Executed successfully in 0.002 s, 0 rows affected. Line 1, column 1 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 26 Line 6, column 1 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')) probability from resultset group by resultset.ballNumber); INSERT INTO d' at line 1 Line 31, column 51 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') score from resultset r inner join (select r.drawDate, r.ballNumber, p.probabi' at line 1 Line 39, column 114 Execution finished after 0.002 s, 3 error(s) occurred. What am I doing wrong? I seem to have exhausted my limited mental abilities!

    Read the article

  • Visual Web Developer 2008 Express and XHTML 1.1 (not applying)

    - by Mike Valeriano
    Hello. I may be missing something since I'm not used to work with IDEs for web development, so please understand if I'm doing something stupid. I've picked a copy of Beginning ASP.NET 3.5 in C# and VB to try and learn this thing quickly. I'm no HTML guru, but I know something about the DTDs and I want to either use XHTML 1.0 Strict or XHTML 1.1 while learning the ins and outs of ASP.NET. Following the book (just started actually), I'm not having any trouble understanding the concepts, since I have a C# background, but what I don't understand is how VWD goes about applying the schema you select for validation. The book explains that the drop-down list on the toolbar is enough to set this, so that's what I did: I've selected XHTML 1.1 (since there is no 1.0 strict option, what I find really odd) and then started the project. The thing is that the code generated automatically for the Default page had the XHTML 1.0 transitional DTD. Every other page added had the same DTD, even though XHTML 1.1 is still the selected schema in the drop-down list. I decided to test it out and there it was: inserting some text in the design view and then applying a bold formatting just inserted < b tags on the code. Changing color does add a span tag with added CSS though. What I want to know is: if I want strict XHTML (or 1.1) should I just code it manually? Or is there a "fix" for this problem (having a schema selected but not applied by the IDE)? Am I missing something really easy and dumb? I have no problem with coding it manually - I actually prefer doing that. The thing is that I really wanna try this WYSIWYG approach for once, since some developers swear by it. Plus I don't know yet if I'll need special tags for ASP.NET, so I think having them inserted automatically should be the best practice. I couldn't find any similar problems around (MSDN, Google, here), and as far as the book goes (up to the point I've read), this is the expected VWD behavior, which I find suspect at least. Sorry for the long text (and poor English - not my primary language). Thanks in advance for any help/tips.

    Read the article

  • Arranging models, views, controllers in a Kohana 3 project

    - by Pekka
    I'm looking at how to set up a mid-sized web application with Kohana 3. I have implemented MVC patterns in the past but never worked against a "formalized" MVC framework so I'm still getting my head around the terminology - toying around with basic examples, building views and templates, and so on. I'm progressing fairly well but I want to set up a real-world web project (one of my own that I've been planning for quite some time now) as a learning object. I learn best by example, but example-based documentation is a bit sparse for Kohana 3 right now - they say so themselves on the site. While I'm not worried about getting into the framework soon enough, I'm a bit concerned about arranging a healthily structured code base from the start - i.e. how to split up controllers, how to name them, and how to separate the functionality into the appropriate models. My application could, in its core, be described as a business directory with a main businesses table. Businesses can be listed by category and by street name. Each business has a detail page. Business owners can log in and edit their business's entry. Businesses can post offers into an offers table. I know this is pretty vague, but I don't want to cram too much information into this question. I'll be more than happy to go into more detail if needed. Supposing I have all the basic functionality worked out and in place already - list all businesses, edit business, list businesses by street name, create offer, and so on, and I'm just looking for how to fit the functionality into a MVC pattern and into a Kohana application structure that can be easily extended: Do you know real-life, publicly accessible examples of "database-heavy" applications like directories, online communities... with a log-in area built on Kohana 3 where I could take a peek how they do it? Are there conventions or best practices on how to structure an extendable login area for end users in a Kohana project that is not only able to handle a business directory page, but further products on separate pages as well? Do you know application structuring HOWTOs or best practices for Kohana 3 not mentioned in the user guide and the inofficial Wiki? Have you built something similar and could give me some recommendations?

    Read the article

  • Design question for WinForms (C#) app, using Entity Framework

    - by cdotlister
    I am planning on writing a small home budget application for myself, as a learning excercise. I have built my database (SQL Server), and written a small console application to interact with it, and test out scenarios on my database. Once I am happy, my next step would be to start building the application - but I am already wondering what the best/standard design would be. I am palnning on using Entity Framework for handling my database entities... then linq to sql/objects for getting the data, all running under a WinForms (for now) application. My plan (I've never used EF... and most of my development background is Web apps) is to have my database... with Entity Framework in it's own project.. which has the connection to the database. This project would expose methods such as 'GetAccount()', 'GetAccount(int accountId)' etc. I'd then have a service project that references my EF project. And on top of that, my GUI project, which makes the calls to my service project. But I am stuck. Lets say I have a screen that displays a list of Account types (Debit, Credit, Loan...). Once I have selected one, the next drop down shows a list of accounts I have that suite that account type. So, my OnChange event on my DropDown on the account type control will make a call to the serviceLayer project, 'GetAccountTypes()', and I would expect back a List< of Account Types. However, the AccountType object ... what is that? That can't be the AccountType object from my EF project, as my GUI project doesn't have reference to it. Would I have to have some sort of Shared Library, shared between my GUI and my Service project, with a custom built AccountType object? The GUI can then expect back a list of these. So my service layer would have a method: public List<AccountType> GetAccountTypes() That would then make a call to a custom method in my EF project, which would probably be the same as the above method, except, it returns an list of EF.Data.AccountType (The Entity Framework generated Account Type object). The method would then have the linq code to get the data as I want it. Then my service layer will get that object, and transform it unto my custom AccountType object, and return it to the GUI. Does that sound at all like a good plan?

    Read the article

  • Validating String Characters as Numeric w/ Pascal (FastReport 4)

    - by user2525015
    I'm new to Pascal and FastReport. This question can probably be answered without knowledge of FastReport. Pascal is Delphi. FastReport4. I have a text box accepting an 8 character string as input. Each character should be numeric. I'm attempting to validate each character as numeric. I've tried using the val function... Procedure Val(S : String; var R: Real; Code : Integer); begin end; procedure thisinputOnChange(Sender: TfrxComponent); var S : String; error : Integer; R : Real; begin S := thisinput.lines.text; Val (S, R, error); If error > 0 then Button2.enabled := False; end; I got this code online. The explanation says that the function will return an error with a code greater than zero if the character cannot be converted to an integer. Is that explanation correct? Am I misinterpreting? Right now I am trying to set a button's enabled property to false if the validation fails. I might change that to a message. For now, I would like to get it to work by setting the button property. I'm not sure if I should be using the onChange event or another event. I'm also not sure if I need to send the input to the val function in a loop. Like I said, I'm just learning how to use this function. I am able to validate the length. This code works... procedure thisinputOnChange(Sender: TfrxComponent); begin if length(thisinput.lines.text) = 8 then Button2.enabled := True; end; Any suggestions? Should I use the val function or something else? Let me know if I need to provide more info. I might not be able to check back until later, though. Thanks for any help.

    Read the article

  • Haskell: how to get through 'no instance for' ?

    - by artemave
    I am learning Haskell. I am on the 8th chapter of this book. The main thing I've learned so far is that Haskell is very unfriendly to me and it bites my ass where possible. Moreover... Heck! Enough mourning, to business. Here is the code: module GlobRegex ( globToRegex, matchesGlob ) where import Text.Regex.Posix import Text.Regex.Posix.String import Text.Regex.Base.RegexLike data CaseOpt = Case | NoCase deriving (Eq) matchesGlob :: String -> String -> CaseOpt -> Bool matchesGlob name pat caseopt = match regex name where regex = case caseopt of NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) globToRegex :: String -> String ... And here is how it fails to compile: Prelude Text.Regex.Posix Text.Regex.Base.RegexLike> :load globtoregex\GlobRegex. hs [1 of 1] Compiling GlobRegex ( globtoregex\GlobRegex.hs, interpreted ) globtoregex\GlobRegex.hs:14:31: No instance for (RegexLike regex [Char]) arising from a use of `match' at globtoregex\GlobRegex.hs:14:31-46 Possible fix: add an instance declaration for (RegexLike regex [Char]) In the expression: match regex name In the definition of `matchesGlob': matchesGlob name pat caseopt = match regex name where regex = case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) } globtoregex\GlobRegex.hs:17:23: No instance for (RegexMaker regex CompOption execOpt String) arising from a use of `makeRegex' at globtoregex\GlobRegex.hs:17:23-49 Possible fix: add an instance declaration for (RegexMaker regex CompOption execOpt String) In the expression: makeRegex (globToRegex pat) In a case alternative: Case -> makeRegex (globToRegex pat) In the expression: case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex p at) Case -> makeRegex (globToRegex pat) } Failed, modules loaded: none. To my best understanding, Text.Regex.Posix.String provides instances for RegexLike Regex String and RegexMaker Regex CompOption ExecOption String, so it should work. On the other hand, I can see that regex in the error message is type variable, not a concrete type, so, perhaps not... Anyway, this is where I am stuck. May be there is a common pattern for resolving no instance for type of problems? Or, in Haskell terms, instance of SmartGuess typeclass for no instance for?

    Read the article

  • Using QT to build a WYSIWYG Editor for a Custom Markup Language

    - by Aaron
    I'm new to QT, and am trying to figure out the best means of creating a WYSIWYG editor widget for a custom markup language that displays simple text, images, and links. I need to be able to propagate changes from the WYSIWYG editor to the custom markup representation. As a concrete example of the problem domain, imagine that the custom markup might have a "player" tag which contains a player name and a team name. The markup could look like this: Last week, <player id="1234"><name>Aaron Rodgers</name><team>Packers</team></player> threw a pass. This text would display in the editor as: Last week, Aaron Rodgers of the Packers threw a pass. The player name and the team name would be editable directly within the editor in standard WYSIWYG fashion, so that my users do not have to learn any markup. Also, when the player name is moused-over, a details pop-up will appear about that player, and similarly for the team. With that long introduction, I'm trying to figure out where to start with QT. It seems that the most logical option would be the Rich Text API using a QTextDocument. This approach seems less than ideal given the limitations of a QTextDocument: I can't figure out how to capture navigation events from clicking on links. Following links on click seems to only be enabled when the QTextEdit is readonly. Custom objects that implement QTextObjectInterface are ignored in copy-and-paste operations Any HTML-based markup that is passed to it as Rich Text is retranslated into a series of span tags and lots of other junk, making it extremely difficult to propagate changes from the editor back to the original custom markup. A second option appears to be QWebKit, which allows for live editing of HTML5 markup, so I could specify a two-way translation between the custom markup and HTML5. I'm not clear on how one would propagate changes from the editor back to the original markup in real-time without re-translating the entire document on every text change. The QWebKit solutions looks like awfully bulky to me (Learning WebKit along with QT) to what should be a relatively simple problem. I have also considered implementing the WYSIWYG with a custom class using native QT containers, labels, images, and other widgets manually. This seems like the most flexible approach, and the one most likely not to run into unresolvable problems. However, I'm pretty sure that implementing all the details of a normal text editor (selecting text, font changes, cut-and-paste support, undo/redo, dragging of objects, cursor placement, etc.) will be incredibly time consuming. So, finally, my question: are there any QT gurus out there with some advice on where to start with this sort of project? BTW, I am using QT because the application is a desktop application that needs platform independence.

    Read the article

  • Binary Search Tree in C

    - by heapzero
    Hi, I'm a Python guy. Learning C language and I've been trying to implement Binary Search Tree in C. I wrote down the code, and I've been trying from few hours but, not able to get the output as expected. Please help! Please correct me. #include<stdlib.h> #include<stdio.h> typedef int ElementType; typedef struct TreeNode { ElementType element; struct TreeNode *left, *right; } TreeNode; TreeNode *createTree(){ //Create the root of tree TreeNode *tempNode; tempNode = malloc(sizeof(TreeNode)); tempNode->element = 0; tempNode->left = NULL; tempNode->right = NULL; return tempNode; } TreeNode *createNode(ElementType X){ //Create a new leaf node and return the pointer TreeNode *tempNode; tempNode = malloc(sizeof(TreeNode)); tempNode->element = X; tempNode->left = NULL; tempNode->right = NULL; return tempNode; } TreeNode *insertElement(TreeNode *node, ElementType X){ //insert element to Tree if(node==NULL){ return createNode(X); } else{ if(X < node->element){ node->left = insertElement(node->left, X); } else if(X > node->element){ node->right = insertElement(node->right, X); } else if(X == node->element){ printf("Oops! the element is already present in the tree."); } } } TreeNode *displayTree(TreeNode *node){ //display the full tree if(node==NULL){ return; } displayTree(node->left); printf("| %d ", node->element); displayTree(node->right); } main(){ //pointer to root of tree #2 TreeNode *TreePtr; TreeNode *TreeRoot; TreeNode *TreeChild; //Create the root of tree TreePtr = createTree(); TreeRoot = TreePtr; TreeRoot->element = 32; printf("%d\n",TreeRoot->element); insertElement(TreeRoot, 8); TreeChild = TreeRoot->left; printf("%d\n",TreeChild->element); insertElement(TreeRoot, 2); insertElement(TreeRoot, 7); insertElement(TreeRoot, 42); insertElement(TreeRoot, 28); insertElement(TreeRoot, 1); insertElement(TreeRoot, 4); insertElement(TreeRoot, 5); // the output is not as expected :( displayTree(TreeRoot); }

    Read the article

  • Android App to call a number on button click

    - by FosterZ
    hey guys this is my 1st android app(learning), so i want to call a number given in the textbox but i'm getting error as "The application 'xyz'(process com.adroid) has stoped unexpectedly".. following the code i have done so far... where m doing wrong ?? EditText txtPhn; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button callButton = (Button)findViewById(R.id.btnCall); txtPhn = (EditText)findViewById(R.id.txtPhnNumber); callButton.setOnClickListener(new OnClickListener() { public void onClick(View v) { try { Intent callIntent = new Intent(Intent.ACTION_CALL); callIntent.setData(Uri.parse("tel:"+txtPhn.getText().toString())); startActivity(callIntent); } catch (ActivityNotFoundException activityException) { Log.e("Calling a Phone Number", "Call failed", activityException); } } }); } EDITED LogCat 03-09 11:23:25.874: ERROR/AndroidRuntime(370): FATAL EXCEPTION: main 03-09 11:23:25.874: ERROR/AndroidRuntime(370): java.lang.SecurityException: Permission Denial: starting Intent { act=android.intent.action.CALL dat=tel:xxx-xxx-xxxx flg=0x10000000 cmp=com.android.phone/.OutgoingCallBroadcaster } from ProcessRecord{40738d70 370:org.krish.android/10034} (pid=370, uid=10034) requires android.permission.CALL_PHONE 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.os.Parcel.readException(Parcel.java:1322) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.os.Parcel.readException(Parcel.java:1276) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.app.ActivityManagerProxy.startActivity(ActivityManagerNative.java:1351) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1374) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.app.Activity.startActivityForResult(Activity.java:2827) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.app.Activity.startActivity(Activity.java:2933) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at org.krish.android.caller$1.onClick(caller.java:29) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.view.View.performClick(View.java:2485) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.view.View$PerformClick.run(View.java:9080) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.os.Handler.handleCallback(Handler.java:587) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.os.Handler.dispatchMessage(Handler.java:92) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.os.Looper.loop(Looper.java:123) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at android.app.ActivityThread.main(ActivityThread.java:3683) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at java.lang.reflect.Method.invokeNative(Native Method) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at java.lang.reflect.Method.invoke(Method.java:507) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 03-09 11:23:25.874: ERROR/AndroidRuntime(370): at dalvik.system.NativeStart.main(Native Method)

    Read the article

  • Advice on displaying and allowing editing of data using ASP.NET MVC?

    - by Remnant
    I am embarking upon my first ASP.NET MVC project and I would like to get some input on possible ways to display database data and general best practice. In short, the body of my webpage will show data from my database in a table like format, with each table row showing similar data. For example: Name Age Position Date Joined Jon Smith 23 Striker 18th Mar 2005 John Doe 38 Defender 3rd Jan 1988 In terms of functionality, primarily I’d like to give the user the ability to edit the data and, after the edit, commit the edit to the database and refresh the view.The reason I want to refresh the view is because the data is date ordered and I will need to re-sort if the user edits a date field. My main question is what architecture / tools would be best suited to this fulfil my requirements at a high level? From the research I have done so far my initial conclusions were: ADO.NET for data retrieval. This is something I have used before and feel comfortable with. I like the look of LINQ to SQL but don’t want to make the learning curve any steeper for my first outing into MVC land just yet. Partial Views to create a template and then iterate through a datatable that I have pulled back from my database model. jQuery to allow the user to edit data in the table, error check edited data entries etc. Also, my intial view was that caching the data would not be a key requirement here. The only field a user will be able to update is the field and, if they do, I will need to commit that data to the database immediately and then refresh the view (as the data is date sorted). Any thoughts on this? Alternatively, I have seen some jQuery plug-ins that emulate a datagrid and provide associated functionality. My first thoughts are that I do not need all the functionality that comes with these plug-ins (e.g. zebra striping, ability to sort by column using sort glyph in column headers etc .) and I don’t really see any benefit to this over and above the solution I have outlined above. Again, is there reason to reconsider this view? Finally, when a user edits a date , I will need to refresh the view. In order to do this I had been reading about Html.RenderAction and this seemed like it may be a better option than using Partial Views as I can incorporate application logic into the action method. Am I right to consider Html.RenderAction or have I misunderstood its usage? Hope this post is clear and not too long. I did consider separate posts for each topic (e.g. Partial View vs. Html.RenderAction, when to use jQury datagrid plug-in) but it feels like these issues are so intertwined that they need to be dealt with in contect of each other. Thanks

    Read the article

  • Getting PHP error/warnings when using CodeIgniter 2 to send email

    - by Sparky672
    I'm using Ion Auth and trying to implement the forgotten password feature which relies upon an email being sent from CI. My LAMP server is on a shared cPanel account and uses sendmail. However, I have the ability to over-ride any PHP settings with my own php.ini file in the public_html directory. As per the CodeIgniter 2 documentation for configuring email sending, I have done the following... 1) created a file called located at application/config/email.php 2) email.php contains this code: <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); /* | ------------------------------------------------------------------- | EMAIL SENDING SETTINGS | ------------------------------------------------------------------- */ $config['protocol'] = 'sendmail'; /* End of file email.php */ /* Location: ./application/config/email.php */ 3) The in the application/config/ion_auth.php file, I set this value to TRUE $config['use_ci_email'] = TRUE; The email is successfully sent, but I get a variety of PHP Error Warnings on all pages. These appear on all pages, sometimes two or three times in a row: A PHP Error was encountered Severity: Warning Message: date() [function.date]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead Filename: libraries/Email.php Line Number: 704 A PHP Error was encountered Severity: Warning Message: date() [function.date]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead Filename: libraries/Email.php Line Number: 709 In addition to the above, these two also show up after the forgotten password form is submitted: A PHP Error was encountered Severity: Warning Message: Cannot modify header information - headers already sent by (output started at /home/username/codeigniter/system/core/Exceptions.php:185) Filename: libraries/Session.php Line Number: 675 A PHP Error was encountered Severity: Warning Message: Cannot modify header information - headers already sent by (output started at /home/username/codeigniter/system/core/Exceptions.php:185) Filename: helpers/url_helper.php Line Number: 540 I'm not sure why I would be getting these Error Warnings or how else I am supposed to configure my email sending options. I don't see any other email sending options in the documentation that is related to these particular Warning Messages. When I remove my config/email.php file AND set Ion Auth's use_ci_email to FALSE, the Error Warnings go away. Where did I go wrong? Just before I hit the submit button, I solved this problem. I'm still going to post this question as a learning experience for others. If nobody solves this after a reasonable amount of time, I'll post the solution.

    Read the article

  • Easiest Way To Get Started In Dot Net

    - by Avery Payne
    Ok, so the initial search in StackOverflow shows nothing related for this question. So here it goes: Let's pretend for a moment that you're just getting started in a career in computer programming. Let's say that, for whatever reason, you decide to use the .Net framework as a basis for your programming. Let's also say that you've been exposed to some programming background, but not one in .Net, so it seems foreign to you at first. And lastly, you don't have the benefit of 25 years of exposure to the Win32 API, which explains why it seems so foreign to you when you start looking at it. So the questions are: What is a comprehensive overview of what .Net is? It appears to be a combination of a runtime environment, a set of languages, a common set of libraries, and perhaps a few other things...so it's about as clear as mud. Specifically, what are the key components to .Net? What is the easiest way to understand .Net programming with regard to available APIs? Which language would best suit beginning programming out of the "stock" languages that Microsoft has to offer? (C++, C#, VB, etc.) What are some differences between .Net programming and programming in a procedural language (aka Pascal, Modula, etc.) What are some differences between .Net programming and programming in a "traditional" object-oriented language? (aka Smalltalk, Java, Python, Ruby, etc.) As I currently understand it, the CLR provides a foundation for all of the other languages to run on. What are some of the inherent limitations of the CLR? Given the enormous amount of API to cover, would it even be worth learning a .Net language (using the Microsoft APIs) given that you would not have prior exposure to Win32 programming? Let's say you write a for-profit program with .Net. Can you resell the program without running afoul of licensing issues? Let's say you write a gratis (free) program with .Net. Can you offer the program to the public under a "free" license (GPL, BSD, Artistic, etc.) without running afoul of licensing issues? Thank you in advance for your patience.

    Read the article

  • Overloading *(iterator + n) and *(n + iterator) in a C++ iterator class?

    - by exscape
    (Note: I'm writing this project for learning only; comments about it being redundant are... uh, redundant. ;) I'm trying to implement a random access iterator, but I've found very little literature on the subject, so I'm going by trial and error combined with Wikpedias list of operator overload prototypes. It's worked well enough so far, but I've hit a snag. Code such as exscape::string::iterator i = string_instance.begin(); std::cout << *i << std::endl; works, and prints the first character of the string. However, *(i + 1) doesn't work, and neither does *(1 + i). My full implementation would obviously be a bit too much, but here's the gist of it: namespace exscape { class string { friend class iterator; ... public: class iterator : public std::iterator<std::random_access_iterator_tag, char> { ... char &operator*(void) { return *p; // After some bounds checking } char *operator->(void) { return p; } char &operator[](const int offset) { return *(p + offset); // After some bounds checking } iterator &operator+=(const int offset) { p += offset; return *this; } const iterator operator+(const int offset) { iterator out (*this); out += offset; return out; } }; }; } int main() { exscape::string s = "ABCDEF"; exscape::string::iterator i = s.begin(); std::cout << *(i + 2) << std::endl; } The above fails with (line 632 is, of course, the *(i + 2) line): string.cpp: In function ‘int main()’: string.cpp:632: error: no match for ‘operator*’ in ‘*exscape::string::iterator::operator+(int)(2)’ string.cpp:105: note: candidates are: char& exscape::string::iterator::operator*() *(2 + i) fails with: string.cpp: In function ‘int main()’: string.cpp:632: error: no match for ‘operator+’ in ‘2 + i’ string.cpp:434: note: candidates are: exscape::string exscape::operator+(const char*, const exscape::string&) My guess is that I need to do some more overloading, but I'm not sure what operator I'm missing.

    Read the article

  • Is this (Lock-Free) Queue Implementation Thread-Safe?

    - by Hosam Aly
    I am trying to create a lock-free queue implementation in Java, mainly for personal learning. The queue should be a general one, allowing any number of readers and/or writers concurrently. Would you please review it, and suggest any improvements/issues you find? Thank you. import java.util.concurrent.atomic.AtomicReference; public class LockFreeQueue<T> { private static class Node<E> { E value; volatile Node<E> next; Node(E value) { this.value = value; } } private AtomicReference<Node<T>> head, tail; public LockFreeQueue() { // have both head and tail point to a dummy node Node<T> dummyNode = new Node<T>(null); head = new AtomicReference<Node<T>>(dummyNode); tail = new AtomicReference<Node<T>>(dummyNode); } /** * Puts an object at the end of the queue. */ public void putObject(T value) { Node<T> newNode = new Node<T>(value); Node<T> prevTailNode = tail.getAndSet(newNode); prevTailNode.next = newNode; } /** * Gets an object from the beginning of the queue. The object is removed * from the queue. If there are no objects in the queue, returns null. */ public T getObject() { Node<T> headNode, valueNode; // move head node to the next node using atomic semantics // as long as next node is not null do { headNode = head.get(); valueNode = headNode.next; // try until the whole loop executes pseudo-atomically // (i.e. unaffected by modifications done by other threads) } while (valueNode != null && !head.compareAndSet(headNode, valueNode)); T value = (valueNode != null ? valueNode.value : null); // release the value pointed to by head, keeping the head node dummy if (valueNode != null) valueNode.value = null; return value; }

    Read the article

  • json problems with making a ruby on rails application

    - by Prince Merdz
    So I'm using Bitnami to learn Ruby on Rails. I have also previously tried the manual installation for ruby and rails and was met by the same problem so I thought I should try first the easy package deal of Bitnami. Anyway my problem with json is that it causes the bundle install to fail. First the auto bundle install that rails new does fails because of an ssl error. Which is easily solved by changing the source in the gemfile which is https to http. However when I try to bundle install it does another error when it tries to install json. C:\RubyStack-3.2.7-0\projects\testing>bundle install Fetching gem metadata from http://rubygems.org/......... Using rake (0.9.2.2) Using i18n (0.6.0) Using multi_json (1.3.6) Installing activesupport (3.2.8) Using builder (3.0.0) Installing activemodel (3.2.8) Using erubis (2.7.0) Using journey (1.0.4) Using rack (1.4.1) Using rack-cache (1.2) Using rack-test (0.6.1) Using hike (1.2.1) Using tilt (1.3.3) Using sprockets (2.1.3) Installing actionpack (3.2.8) Using mime-types (1.19) Using polyglot (0.3.3) Using treetop (1.4.10) Using mail (2.4.4) Installing actionmailer (3.2.8) Using arel (3.0.2) Using tzinfo (0.3.33) Installing activerecord (3.2.8) Installing activeresource (3.2.8) Using bundler (1.1.5) Using coffee-script-source (1.3.3) Using execjs (1.4.0) Using coffee-script (2.2.0) Using rack-ssl (1.3.2) Installing json (1.7.5) with native extensions Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension . C:/RUBYST~1.7-0/ruby/bin/ruby.exe extconf.rb creating Makefile make 0 [main] echo 5244 open_stackdumpfile: Dumping stack trace to echo.exe.sta ckdump make: *** [generator-i386-mingw32.def] Error 5 Gem files will remain installed in C:/RUBYST~1.7-0/ruby/lib/ruby/gems/1.9.1/gems /json-1.7.5 for inspection. Results logged to C:/RUBYST~1.7-0/ruby/lib/ruby/gems/1.9.1/gems/json-1.7.5/ext/j son/ext/generator/gem_make.out An error occured while installing json (1.7.5), and Bundler cannot continue. Make sure that `gem install json -v '1.7.5'` succeeds before bundling. This is the gem_make.out file it produces after trying to install json (btw windows also produces an error that echo.exe has stopped working while running the gem install json) C:/RUBYST~1.7-0/ruby/bin/ruby.exe extconf.rb creating Makefile make 0 [main] echo 5244 open_stackdumpfile: Dumping stack trace to echo.exe.stackdump make: *** [generator-i386-mingw32.def] Error 5 I can't even start learning ror for the setup is already a huge pain. (btw I have no prior experience with web frameworks, just desktop programming). help?

    Read the article

< Previous Page | 293 294 295 296 297 298 299 300 301 302 303 304  | Next Page >