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  • How to convert a printer driver to a stand-alone console application which can generate a printer fi

    - by Thorbjørn Ravn Andersen
    I have a situation where the only way to generate a certain datafile is to print it manually to FILE: under Windows and save it in a file for further processing. I would really like to have a small stand-alone program which embeds this binary printer driver so I can run it from a batch file and have it generate that binary file for me, as we can then fully automate the "save file in Visio, 'print' it and upload it to the final destination and trigger a remote test". Is this possible with a suitable Windows SDK? I am a Java programmer, so I do not know Visual Studio and the possibilities with MSDN - yet! - but I'd appreciate pointers. EDIT: I have the installation files for that printer driver, both 32 and 64 bit. Older versions may include a 16 bit driver. EDIT: The "print to FILE:" functionality is just what was recommended by the documentation. I have played a little bit with using the LPR-protocol to see what it can do. I'd still prefer the "invoke small binary" approach.

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  • Delphi: Alternative to using Reset/ReadLn for text file reading

    - by Ian Boyd
    i want to process a text file line by line. In the olden days i loaded the file into a StringList: slFile := TStringList.Create(); slFile.LoadFromFile(filename); for i := 0 to slFile.Count-1 do begin oneLine := slFile.Strings[i]; //process the line end; Problem with that is once the file gets to be a few hundred megabytes, i have to allocate a huge chunk of memory; when really i only need enough memory to hold one line at a time. (Plus, you can't really indicate progress when you the system is locked up loading the file in step 1). The i tried using the native, and recommended, file I/O routines provided by Delphi: var f: TextFile; begin Reset(f, filename); while ReadLn(f, oneLine) do begin //process the line end; Problem withAssign is that there is no option to read the file without locking (i.e. fmShareDenyNone). The former stringlist example doesn't support no-lock either, unless you change it to LoadFromStream: slFile := TStringList.Create; stream := TFileStream.Create(filename, fmOpenRead or fmShareDenyNone); slFile.LoadFromStream(stream); stream.Free; for i := 0 to slFile.Count-1 do begin oneLine := slFile.Strings[i]; //process the line end; So now even though i've gained no locks being held, i'm back to loading the entire file into memory. Is there some alternative to Assign/ReadLn, where i can read a file line-by-line, without taking a sharing lock? i'd rather not get directly into Win32 CreateFile/ReadFile, and having to deal with allocating buffers and detecting CR, LF, CRLF's. i thought about memory mapped files, but there's the difficulty if the entire file doesn't fit (map) into virtual memory, and having to maps views (pieces) of the file at a time. Starts to get ugly. i just want Reset with fmShareDenyNone!

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  • How much should the AppDelegate do?

    - by Rudiger
    I'm designing quite a large App and on startup it will create sessions with a few different servers. As they are creating a session which is used across all parts of the app its something I thought would be best in App Delegate. But the problem is I need the session progress to be represented on the screen. I plan to have a UIToolBar at the bottom of the main menu which I don't want to cover with the progress bar but cover the UIView above it.So the way I see it I could do it a few different ways. 1) Have the App Delegate establish the sessions and report the progress to the main menu class so it can represent it in the progress bar (will I have any issues doing this if the sessions are created in a separate thread?), 2) have the App delegate display the main menu (UIView with a bunch of buttons and UIToolBar) and have it track and display the progress (I have never displayed anything in the App Delegate but assume you can do this but its not recommended) or 3) have the App Delegate just push the main menu and have the mainMenu class create the sessions and display the progress bar. 4) I think the other way to do it is to create the sessions in a delegate class and have the delegate set to mainMenu rather than self (AppDelegate), although I've never used anything other then self so not sure if this will work or if I will be able to close the thread (through calling super maybe?) as its running in the AppDelegate rather than the delegate of the class. As I've kinda said before the sessions are being created in a class in a separate thread so it wont lock the UI and I think the best way is the first but am I going to have issues having it running in a separate thread, reporting back to the app delegate and then sending that message to the mainMenu view? I hope that all makes sense, let me know if you need any further clarification. Any information is appreciated Cheers,

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  • Best Practice With JFrame Constructors?

    - by David Barry
    In both my Java classes, and the books we used in them laying out a GUI with code heavily involved the constructor of the JFrame. The standard technique in the books seems to be to initialize all components and add them to the JFrame in the constructor, and add anonymous event handlers to handle events where needed, and this is what has been advocated in my class. This seems to be pretty easy to understand, and easy to work with when creating a very simple GUI, but seems to quickly get ugly and cumbersome when making anything other than a very simple gui. Here is a small code sample of what I'm describing: public class FooFrame extends JFrame { JLabel inputLabel; JTextField inputField; JButton fooBtn; JPanel fooPanel; public FooFrame() { super("Foo"); fooPanel = new JPanel(); fooPanel.setLayout(new FlowLayout()); inputLabel = new JLabel("Input stuff"); fooPanel.add(inputLabel); inputField = new JTextField(20); fooPanel.add(inputField); fooBtn = new JButton("Do Foo"); fooBtn.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { //handle event } }); fooPanel.add(fooBtn); add(fooPanel, BorderLayout.CENTER); } } Is this type of use of the constructor the best way to code a Swing application in java? If so, what techniques can I use to make sure this type of constructor is organized and maintainable? If not, what is the recommended way to approach putting together a JFrame in java?

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  • I need to implement C# deep copy constructors with inheritance. What patterns are there to choose fr

    - by Tony Lambert
    I wish to implement a deepcopy of my classes hierarchy in C# public Class ParentObj : ICloneable { protected int myA; public virtual Object Clone () { ParentObj newObj = new ParentObj(); newObj.myA = theObj.MyA; return newObj; } } public Class ChildObj : ParentObj { protected int myB; public override Object Clone ( ) { Parent newObj = this.base.Clone(); newObj.myB = theObj.MyB; return newObj; } } This will not work as when Cloning the Child only a parent is new-ed. In my code some classes have large hierarchies. What is the recommended way of doing this? Cloning everything at each level without calling the base class seems wrong? There must be some neat solutions to this problem, what are they? Can I thank everyone for their answers. It was really interesting to see some of the approaches. I think it would be good if someone gave an example of a reflection answer for completeness. +1 awaiting!

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  • How to choose light version of databse system

    - by adopilot
    I am starting one POS (Point of sale) project. Targeting system is going to be written in C# .NET 2 WinForms and as main database server We are going to use MS-SQL Server. As we have a lot of POS devices in chain for one store I will love to have backend local data base system on each POS device. Scenario are following: When main server goes down!! POS application should continue working "off-line" with local database, until connection to main server come up again. Now I am in dilemma which local database is going to be most adoptable for me. Here is some notes for helping me point me in right direction: To be Light "My POS devices art usually old and suffering with performances" To be Free "I have a lot of devices and I do not wont additional cost beside main SQL serer" One day Ill love to try all that port on Mono and Linux OS. Here is what I've researched so far: Simple XML "Light but I am afraid of performance, My main table of items is average of 10K records" SQL-Expres "I am afraid that my POS devices is poor with hardware for SQLExpres, and also hard to install on each device and configure" Less known Advantage Database Server have free distribution of offline ADT system. DBF with extended Library,"Respect for good old DBFs but that era is behind Me with clipper and DBFs" MS Access Sqlite "Mostly like for now, but I am afraid how it is going to pair with MS SQL do they have same Data taypes". I know that in this SO is a lot of subjective data, but at least can someone recommended some others lite database system, or things that I shod most take attention before I choice database.

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  • How do I unit test controllers for an asp.net mvc site that uses StructureMap and NHibernate?

    - by Jim Geurts
    I have an asp.net mvc2 application that is using StructureMap 2.6 and NHibernate 3.x. I would like to add unit tests to the application but am sort of at a loss for how to accomplish it. Say I have a basic controller called Posts that has an action called Index. The controller looks something like: public class PostsController : Controller { private readonly IPostService _postService; public PostsController(IPostService postService) { _postService = postService; } public ActionResult Index() { return View(_postService.QueryOver<Post>().Future()); } } If I wanted to create an nunit test that would verify that the index action is returning all of the posts, how do I go about that? If mocking is recommended, do you just assume that interaction with the database will work? Sorry for asking such a broad question, but my web searches haven't turned up anything decent for how to unit test asp.net mvc actions that use StructureMap (or any other IOC) and NHibernate. btw, if you don't like that I return a QueryOver object from my post service, pretend it is an IQueryable object. I'm using it essentially in the same way.

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  • Really simple JSON serialization in .NET

    - by Evgeny
    I have some simple .NET objects I'd like to serialize to JSON and back again. The set of objects to be serialized is quite small and I control the implementation, so I don't need a generic solution that will work for everything. Since my assembly will be distributed as a library I'd really like to avoid a dependency on some third-party DLL: I just want to give users one assembly that they can reference. I've read the other questions I could find on converting to and from JSON in .NET. The recommended solution of JSON.NET does work, of course, but it requires distributing an extra DLL. I don't need any of the fancy features of JSON.NET. I just need to handle a simple object (or even dictionary) that contains strings, integers, DateTimes and arrays of strings and bytes. On deserializing I'm happy to get back a dictionary - it doesn't need to create the object again. Is there some really simple code out there that I could compile into my assembly to do this simple job? I've also tried System.Web.Script.Serialization.JavaScriptSerializer, but where it falls down is the byte array: I want to base64-encode it and even registering a converter doesn't let me easily accomplish that due to the way that API works (it doesn't pass in the name of the field).

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  • Why is it not good to use $_SESSION in Restful Implementations?

    - by keisimone
    Original Question: i read that for RESTful websites. it is not good to use $_SESSION. Why is it not good? how then do i properly authenticate users without looking up database all the time to check for the user's roles? I read that it is not good to use $_SESSION. http://www.recessframework.org/page/towards-restful-php-5-basic-tips I am creating a WEBSITE, not web service in PHP. and i am trying to make it more RESTful. at least in spirit. right now i am rewriting all the action to use Form tags POST and add in a hidden value called _method which would be "delete" for deleting action and "put" for updating action. however, i am not sure why it is recommended NOT to use $_SESSION. i would like to know why and what can i do to improve. To allow easy authorization checking, what i did was to after logging in the user, the username is stored in the $_SESSION. Everytime the user navigates to a page, the page would check if the username is stored inside $_SESSION and then based on the $_SESSION retrieves all the info including privileges from the database and then evaluates the authorization to access the page based on the info retrieved. Is the way I am implementing bad? not RESTful? how do i improve performance and security? Thank you.

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  • Re-use of database object in sub-sonic

    - by cantabilesoftware
    Yet another newbie SubSonic/ActiveRecord question. Suppose I want to insert a couple of records, currently I'm doing this: using (var scope = new System.Transactions.TransactionScope()) { // Insert company company c = new company(); c.name = "ACME"; c.Save(); // Insert some options company_option o = new company_option(); o.name = "ColorScheme"; o.value = "Red"; o.company_id = c.company_id; o.Save(); o = new company_option(); o.name = "PreferredMode"; o.value = "Fast"; o.company_id = c.company_id; o.Save(); scope.Complete(); } Stepping through this code however, each of the company/company_option constructors go off and create a new myappDB object which just seems wasteful. Is this the recommended approach or should I be trying to re-use a single DB object - and if so, what's the easiest way to do this?

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  • How to send arbitrary ftp commands in C#

    - by cchampion
    I have implemented the ability to upload, download, delete, etc. using the FtpWebRequest class in C#. That is fairly straight forward. What I need to do now is support sending arbitrary ftp commands such as quote SITE LRECL=132 RECFM=FB or quote SYST Here's an example configuration straight from our app.config: <!-- The following commands will be executed before any uploads occur --> <extraCommands> <command>quote SITE LRECL=132 RECFM=FB</command> </extraCommands> I'm still researching how to do this using FtpWebRequest. I'll probably try WebClient class next. Anyone can point me in the right direction quicker? Thanks! UPDATE: I've come to that same conclusion, as of .NET Framework 3.5 FtpWebRequest doesn't support anything except what's in WebRequestMethods.Ftp.*. I'll try a third party app recommended by some of the other posts. Thanks for the help!

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  • How to std::find using a Compare object?

    - by dehmann
    I am confused about the interface of std::find. Why doesn't it take a Compare object that tells it how to compare two objects? If I could pass a Compare object I could make the following code work, where I would like to compare by value, instead of just comparing the pointer values directly: typedef std::vector<std::string*> Vec; Vec vec; std::string* s1 = new std::string("foo"); std::string* s2 = new std::string("foo"); vec.push_back(s1); Vec::const_iterator found = std::find(vec.begin(), vec.end(), s2); // not found, obviously, because I can't tell it to compare by value delete s1; delete s2; Is the following the recommended way to do it? template<class T> struct MyEqualsByVal { const T& x_; MyEqualsByVal(const T& x) : x_(x) {} bool operator()(const T& y) const { return *x_ == *y; } }; // ... vec.push_back(s1); Vec::const_iterator found = std::find_if(vec.begin(), vec.end(), MyEqualsByVal<std::string*>(s2)); // OK, will find "foo"

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  • Implementing a normal website inside ASP.NET MVC 2

    - by cc0
    I have a website consisting of an index.html, a number of style sheet files as well as some javascript files. Then I needed a way for this site to communicate efficiently with a Microsoft SQL Server, so I was recommended to use the MVC framework to facilitate that kind of communication. I created the C#.net controller code needed to output the necessary information from the database using URL parameters, so now I am trying to put the whole web-site together inside the MVC framework. I started an empty project-template in MVC 2 framework. I'm sure there must be a good way to implement the current code into this framework, but I am very uncertain as to what the best approach to this would be. Could anyone point me in the right direction here? I'm not sure whether I need to change any of the current HTML, or exactly what to add to it. I'd love to see some kind of guide or tutorial, or just any advice I can get as I try to learn this. Any help is very much appreciated!

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  • Passing Binary Data to a Stored Procedure in SQL Server 2008

    - by Joe Majewski
    I'm trying to figure out a way to store files in a database. I know it's recommended to store files on the file system rather than the database, but the job I'm working on would highly prefer using the database to store these images (files). There are also some constraints. I'm not an admin user, and I have to make stored procedures to execute all the commands. This hasn't been of much difficulty so far, but I cannot for the life of me establish a way to store a file (image) in the database. When I try to use the BULK command, I get an error saying "You do not have permission to use the bulk load statement." The bulk utility seemed like the easy way to upload files to the database, but without permissions I have to figure a work-a-round. I decided to use an HTML form with a file upload input type and handle it with PHP. The PHP calls the stored procedure and passes in the contents of the file. The problem is that now it's saying that the max length of a parameter can only be 128 characters. Now I'm completely stuck. I don't have permissions to use the bulk command and it appears that the max length of a parameter that I can pass to the SP is 128 characters. I expected to run into problems because binary characters and ascii characters don't mix well together, but I'm at a dead end... Thanks

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  • [WEB] Local/Dev/Live deployment - best workflow

    - by Adam Kiss
    Hello, situation We our little company with 3 people, each has a localhost webserver and most projects (previous and current) are on one PC network shared disk. We have virtual server, where some of our clients' sites and our site. Our standard workflow is: Coder PC ? Programmer localhost ? dev domain (client.company.com) ? live version (client.com) It often happens, that there are two or three guys working on same projects at the same time - one is on dev version, two are on localhost. When finished, we try to synchronize the files on dev version and ideally not to mess (thanks ILMV:]) up any files, which *knock knock * doesn't happen often. And then one of us deploys dev version on live webserver. question we are looking for a way to simplify this workflow while updating websites - ideally some sort of diff uploader or VCS probably (Git/SVN/VCS/...), but we are not completely sure where to begin or what way would be ideal, therefore I ask you, fellow stackoverflowers for your experience with website / application deployment and recommended workflow. We probably will also need to use Mac in process, so if it won't be a problem, that would be even better. Thank you

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  • What is the easiest way to read wav-files using Python [summary]?

    - by Roman
    I want to use Python to access a wav-file and write its content in a form which allows me to analyze it (let's say arrays). I heard that "audiolab" is a suitable tool for that (it transforms numpy arrays into wav and vica versa). I have installed the "audiolab" but I had a problem with the version of numpy (I could not "from numpy.testing import Tester"). I had 1.1.1. version of numpy. I have installed a newer version on numpy (1.4.0). But then I got a new set of errors: Traceback (most recent call last): File "test.py", line 7, in import scikits.audiolab File "/usr/lib/python2.5/site-packages/scikits/audiolab/init.py", line 25, in from pysndfile import formatinfo, sndfile File "/usr/lib/python2.5/site-packages/scikits/audiolab/pysndfile/init.py", line 1, in from _sndfile import Sndfile, Format, available_file_formats, available_encodings File "numpy.pxd", line 30, in scikits.audiolab.pysndfile._sndfile (scikits/audiolab/pysndfile/_sndfile.c:9632) ValueError: numpy.dtype does not appear to be the correct type object I gave up to use audiolab and thought that I can use "wave" package to read in a wav-file. I asked a question about that but people recommended to use scipy instead. OK, I decided to focus on scipy (I have 0.6.0. version). But when I tried to do the following: from scipy.io import wavfile x = wavfile.read('/usr/share/sounds/purple/receive.wav') I get the following: Traceback (most recent call last): File "test3.py", line 4, in <module> from scipy.io import wavfile File "/usr/lib/python2.5/site-packages/scipy/io/__init__.py", line 23, in <module> from numpy.testing import NumpyTest ImportError: cannot import name NumpyTest So, I gave up to use scipy. Can I use just wave package? I do not need much. I just need to have content of wav-file in human readable format and than I will figure out what to do with that.

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  • why is OOP hard for me?

    - by netrox
    I have trouble writing OOP in PHP... I understand the concept but I never create classes for my projects... mainly because it's often a small project and nothing complex. But when I read OOP, it seems more difficult to code than writing simple procedural statements. It also seems to take a lot of room as well with so many empty abstract classes and that can be easily lost in the land of objects... it's becoming like a junkyard to me. Also, I noticed that virtually all instructions on how to use OOP use "car" or "cat" or "dog" analogies. Hello... we're not dealing with animals or cars... we're dealing with windows or consoles. You can talk about analogies to death and I will never learn. What I want is see a code that's written to show how objects are created - not, "aCow-moo!" For example, I want to see a browser window object displaying say... three inputs. I want to see an "object" created to output a window with three inputs then I want to see how overriding works, like change the window object to display only two inputs instead of three inputs. I think that would make learning more easy, wouldn't it? Any recommended tutorials of that nature instead of quacks, moos, and woofs.

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  • wcf trying to set up tracing to debug, not writing to log file

    - by joey j
    here's my web.config, running a WCF service in an application on IIS7, but nothing is being written to the specified file. permission on the file has been granted for everyone. </listeners> I can add a service reference just fine. I then try to call the service from a windows app and, after a few minutes, get an error on the machine running the windows app "Client is unable to finish the security negotiation within the configured timeout (00:00:00). The current negotiation leg is 1 (00:00:00)." but absolutely nothing is written to the trace log file specified in config. Is there something else I need to do to enable tracing? thanks for your help EDIT: "sources" section now matches the section recommended here: http://msdn.microsoft.com/en-us/library/aa702726.aspx I've added the "diagnostics and the event viewer shows: "Message Logging has been turned on. Sensitive information may be logged in the clear, even if it was encrypted on the wire: for example, message bodies. Process Name: w3wp Process ID: 1784 " but the log file is still empty

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  • Python alignment of assignments (style)

    - by ikaros45
    I really like following style standards, as those specified in PEP 8. I have a linter that checks it automatically, and definitely my code is much better because of that. There is just one point in PEP 8, the E251 & E221 don't feel very good. Coming from a JavaScript background, I used to align the variable assignments as following: var var1 = 1234; var2 = 54; longer_name = 'hi'; var lol = { 'that' : 65, 'those' : 87, 'other_thing' : true }; And in my humble opinion, this improves readability dramatically. Problem is, this is dis-recommended by PEP 8. With dictionaries, is not that bad because spaces are allowed after the colon: dictionary = { 'something': 98, 'some_other_thing': False } I can "live" with variable assignments without alignment, but what I don't like at all is not to be able to pass named arguments in a function call, like this: some_func(length= 40, weight= 900, lol= 'troll', useless_var= True, intelligence=None) So, what I end up doing is using a dictionary, as following: specs = { 'length': 40, 'weight': 900, 'lol': 'troll', 'useless_var': True, 'intelligence': None } some_func(**specs) or just simply some_func(**{'length': 40, 'weight': 900, 'lol': 'troll', 'useless_var': True, 'intelligence': None}) But I have the feeling this work around is just worse than ignoring the PEP 8 E251 / E221. What is the best practice?

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  • What's the best way to learn .NET?

    - by duffymo
    I've been developing Java EE for quite a while now. I've used WebLogic, Tomcat, Spring, and Hibernate extensively, so I have a mental model of what features are available and how things are developed and deployed. The problem that I have with .NET is that I don't have a clear mapping of its features onto Java EE. Here's what I know so far: Java EE - .NET Java - C# JAR - DLL WAR - ? (deployment in general) EAR - ? (deployment in general) Tomcat - IIS web server JSP - ASP? JDBC - ODBC JMS - MSMQ JTA - Microsoft Transaction Manager So much of the functionality that WebLogic handles appears to be dispersed throughout the Windows OS. My confusion kicks in when I see the waves of books at Borders - VB.NET, ASP.NET, C#, etc. If I'm not a VB programmer, would it be possible to stick with C# and write enterprise apps that are the equivalent of what I'm used to with Java EE? If there were a Top Three list of books to learn from, what would they be? The "Head First" series has certainly been successful for Java. http://www.amazon.com/Head-First-C-Brain-Friendly-Guides/dp/0596514824/ref=sr_1_1?ie=UTF8&s=books&qid=1224121193&sr=8-1 Equally well recommended for .NET learning? Thanks. - %

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  • Extension methods for encapsulation and reusability

    - by tzaman
    In C++ programming, it's generally considered good practice to "prefer non-member non-friend functions" instead of instance methods. This has been recommended by Scott Meyers in this classic Dr. Dobbs article, and repeated by Herb Sutter and Andrei Alexandrescu in C++ Coding Standards (item 44); the general argument being that if a function can do its job solely by relying on the public interface exposed by the class, it actually increases encapsulation to have it be external. While this confuses the "packaging" of the class to some extent, the benefits are generally considered worth it. Now, ever since I've started programming in C#, I've had a feeling that here is the ultimate expression of the concept that they're trying to achieve with "non-member, non-friend functions that are part of a class interface". C# adds two crucial components to the mix - the first being interfaces, and the second extension methods: Interfaces allow a class to formally specify their public contract, the methods and properties that they're exposing to the world. Any other class can choose to implement the same interface and fulfill that same contract. Extension methods can be defined on an interface, providing any functionality that can be implemented via the interface to all implementers automatically. And best of all, because of the "instance syntax" sugar and IDE support, they can be called the same way as any other instance method, eliminating the cognitive overhead! So you get the encapsulation benefits of "non-member, non-friend" functions with the convenience of members. Seems like the best of both worlds to me; the .NET library itself providing a shining example in LINQ. However, everywhere I look I see people warning against extension method overuse; even the MSDN page itself states: In general, we recommend that you implement extension methods sparingly and only when you have to. So what's the verdict? Are extension methods the acme of encapsulation and code reuse, or am I just deluding myself?

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  • Multiple on-screen view controllers in iPhone apps

    - by Felixyz
    I'm creating a lot of custom views and controllers in a lot of my apps and so far I've mostly set them up programmatically, with adjustments and instantiations being controlled from plists. However, now I'm transitioning to using Interface Builder as much as possible (wish I had done that before, was always on my back-list). Apple is recommending against having many view controllers being simultaneously active in iPhone apps, with a couple of well-known exceptions. I've never fully understood why it should be bad to have different parts of the interface belong to different controllers, if they have no interdependent functionality at all. Does having multiple controllers risk messing up the responder chain, or is there some other reason that it's not recommended, except for the fact that it's usually not needed? What I want to be able to do is design reusable views and controls in IB, but since a nib is not associated with a view, but with a view controller, it seems I'd have to have different parts of the screen be connected to different controllers. I know it's possible to have other objects than view controllers being instantiated from nibs. Should I look into how to create my own alternative more light-weight controllers (that could be sub-controllers of a UIViewController) which could be instantiated from nibs?

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  • Is extending a base class with non-virtual destructor dangerous in C++

    - by Akusete
    Take the following code class A { }; class B : public A { }; class C : public A { int x; }; int main (int argc, char** argv) { A* b = new B(); A* c = new C(); //in both cases, only ~A() is called, not ~B() or ~C() delete b; //is this ok? delete c; //does this line leak memory? return 0; } when calling delete on a class with a non-virtual destructor with member functions (like class C), can the memory allocator tell what the proper size of the object is? If not, is memory leaked? Secondly, if the class has no member functions, and no explicit destructor behaviour (like class B), is everything ok? I ask this because I wanted to create a class to extend std::string, (which I know is not recommended, but for the sake of the discussion just bear with it), and overload the +=,+ operator. -Weffc++ gives me a warning because std::string has a non virtual destructor, but does it matter if the sub-class has no members and does not need to do anything in its destructor? -- FYI the += overload was to do proper file path formatting, so the path class could be used like class path : public std::string { //... overload, +=, + //... add last_path_component, remove_path_component, ext, etc... }; path foo = "/some/file/path"; foo = foo + "filename.txt"; //and so on... I just wanted to make sure someone doing this path* foo = new path(); std::string* bar = foo; delete bar; would not cause any problems with memory allocation

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  • Modal view becomes partly transparent when dismissing?

    - by Jaanus
    A completely ordinary setup: UIViewController where I push another UIVC: BlahVc *blah = [[BlahVc alloc] initWithNibName:@"Blah" bundle:nil]; UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:blah]; blah.delegate = self; [self presentModalViewController:nav animated:YES]; [nav release]; [blah release]; Details about Blah: to support both landscape and portrait with least effort, I built Blah.xib so that inside Blah's main view, call it view A, there is another view B, with width fixed to 320px, that positions itself in the centre of the screen. With portrait iPhone it fills up the whole screen, with landscape there are margins on the side. So far, so good. Autorotate etc works well. Now, to dismiss blah, I use the recommended setup: inside Blah, I do: [self.delegate blahDidCancel:self]; And in the parent VC, I have: - (void)blahDidCancel:(Blah *)blah { [self dismissModalViewControllerAnimated:YES]; } Both view A's and B's backgrounds are opaque white. Problem: as soon as it hits the dismissModalViewControllerAnimated line, view A seems to become transparent, while view B remains white. This is not a problem in portrait since view B still fills up the screen. But in landscape, the result is that view B is still opaque, but has see-through transparent margins on the side (where view A used to be that has now mysteriously become transparent), from where the parent view contents comes through during the dismissing animation. Why does it seem like view A becomes transparent upon dismissing the modal VC?

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  • Compiling gstreamer plugin in windows

    - by utnapistim
    Hello all, My question: What is the correct way to compile a gstreamer plugin in windows, so that it will be accepted by gstreamer (actually Songbird on top of gstreamer). My setup: I have downloaded the songbird sources following the steps described here and I have a trunk/dependencies/windows-i686-msvc8 directory within my svn sources with all the gstreamer binaries. I have created a gstreamer empty plugin skeleton following the steps detailed in the GStreamer Plugin Writer's Guide, and compiled it against the gstreamer binaries in the Songbird dependencies folder. The compilation was done with VS2010 RC1 (Visual Studio 2008 yelded the same results), using an empty DLL project with the .h and .c files generated using the GStreamer Plugin Writer's Guide. The DLL was lined with libcpmt.lib, libcmt.lib, ws2_32.lib, gobject-2.0.lib, gthread-2.0.lib, gstreamer-0.10-0.lib, glib-2.0.lib, kernel32.lib, nspr4.lib and ignoring all default libraries. I have compiled the files as both .c and .cpp with the same results. Testing: I have installed the Songbird binaries corresponding to the correct svn version, then installed Songbird Developer Tools addon and used it to create an addon for testing my gstreamer plugin. Songbird will not load the pluggin. I have also tried to load it with gst-launch.exe from the trunk/dependencies/windows-i686-msvc8/[...] directory and that generated runtime error R6034: An application has made an attempt to load the C runtime library incorrectly. Most resources I found for this problem recommended restarting or reinstalling windows :(.

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