Search Results

Search found 23271 results on 931 pages for 'static classes'.

Page 382/931 | < Previous Page | 378 379 380 381 382 383 384 385 386 387 388 389  | Next Page >

• Automatically creating C# wrappers from c headers?

  - by Winner

  Is there a way to automatically create p/invoke wrappers for .net from a c header? Of course I could create them by hand, but maintaining them would be painful, and I'd probably make a mistake somewhere resulting in hard to debug crashes. I tried SWIG, but it created full classes where simple structs would be sufficient. I'd prefer if the output worked on mono too, but that is not necessary.

  Read the article

• Correct way to read configuration file and using configuration values

  - by Harza

  I'm reading applications .config file using .NET ConfigurationManager like it should be done, but .... Which one is most preferred option: Read config and store instance of (build in or custom) ConfigurationElement for later use Read config and store only needed values (but not instances of ConfigrationElement classes) for later use Read ConfigurationElement from config always when configuration values are needed These two things are in my mind: Performance impact in case 3 when reading config all the time Problems occuring in case 1 when using cached instances of ConfigurationElements

  Read the article

• How to learn proper C++?

  - by Chris

  While reading a long series of really, really interesting threads, I've come to a realization: I don't think I really know C++. I know C, I know classes, I know inheritance, I know templates (& the STL) and I know exceptions. Not C++. To clarify, I've been writing "C++" for more than 5 years now. I know C, and I know that C and C++ share a common subset. What I've begun to realize, though, is that more times than not, I wind up treating C++ something vaguely like "C with classes," although I do practice RAII. I've never used Boost, and have only read up on TR1 and C++0x - I haven't used any of these features in practice. I don't use namespaces. I see a list of #defines, and I think - "Gracious, that's horrible! Very un-C++-like," only to go and mindlessly write class wrappers for the sake of it, and I wind up with large numbers (maybe a few per class) of static methods, and for some reason, that just doesn't seem right lately. The professional in me yells "just get the job done," the academic yells "you should write proper C++ when writing C++" and I feel like the point of balance is somewhere in between. I'd like to note that I don't want to program "pure" C++ just for the sake of it. I know several languages. I have a good feel for what "Pythonic" is. I know what clean and clear PHP is. Good C code I can read and write better than English. The issue is that I learned C by example, and picked up C++ as a "series of modifications" to C. And a lot of my early C++ work was creating class wrappers for C libraries. I feel like my own personal C-heavy background while learning C++ has sort of... clouded my acceptance of C++ in it's own right, as it's own language. Do the weathered C++ lags here have any advice for me? Good examples of clean, sharp C++ to learn from? What habits of C does my inner-C++ really need to break from? My goal here is not to go forth and trumpet "good" C++ paradigm from rooftops for the sake of it. C and C++ are two different languages, and I want to start treating them that way. How? Where to start? Thanks in advance! Cheers, -Chris

  Read the article

• Qt application crashing immediately without debugging info. How do I track down the problem?

  - by jjacksonRIAB

  I run an Qt app I've built: ./App Segmentation fault I run it with strace: strace ./App execve("./App", ["./App"], [/* 27 vars */]) = 0 --- SIGSEGV (Segmentation fault) @ 0 (0) --- +++ killed by SIGSEGV +++ Process 868 detached Again, no useful info. I run it with gdb: (gdb) run Starting program: /root/test/App Reading symbols from shared object read from target memory...(no debugging symbols found)...done. Loaded system supplied DSO at 0xffffe000 Program received signal SIGSEGV, Segmentation fault. 0x00000001 in ?? () Again, nothing. I run it with valgrind: ==948== Process terminating with default action of signal 11 (SIGSEGV) ==948== Bad permissions for mapped region at address 0x0 ==948== at 0x1: (within /root/test/App) Even if I put in debugging symbols, it doesn't give any more useful info. ldd shows all libraries being linked properly. Is there any other way I can find out what's wrong? I can't even do standard printf, cout, etc debugging. The executable doesn't even seem to start running at all. I rebuilt with symbols, and tried the suggestion below (gdb) break main Breakpoint 1 at 0x45470 (gdb) run Starting program: /root/test/App Breakpoint 1 at 0x80045470 Reading symbols from shared object read from target memory...done. Loaded system supplied DSO at 0xffffe000 Program received signal SIGSEGV, Segmentation fault. 0x00000001 in ?? () I checked for static initializers and I don't seem to have any. Yep, I tried printf, cout, etc. It doesn't even make it into the main routine, so I'm looking for problems with static initializers in link libraries, adding them in one-by-one. I'm not getting any stack traces either.

  Read the article

• Sealed alternative

  - by Jeriho

  According to "Programming in scala" a sealed class cannot have any new subclasses added except the ones in the same ?le. In the same book was described a way to enumerate classes that can extend class or trait in multiple files. I have forgotten it and can't find again. Remind it to me, please.

  Read the article

• time series in python up to microseconds

  - by Abruzzo Forte e Gentile

  Hi All I would like to handle time series in python. I have been suggested to use scikit.timeseries but I need to handle up to microseconds and this last, as far as I know, handles up to milliseconds. Do you know any other library able to do that? At some point I need to merge 2 time series sampled at different time, and I would like to avoid rewriting such kind of features or any new classes from scratch whenever it is possible. I thank you all AFG

  Read the article

• How to write Java-like enums in C++ ?

  - by Rahul G

  Coming from Java background, I find C++'s enums very lame. I wanted to know how to write Java-like enums (the ones in which the enum values are objects, and can have attributes and methods) in C++. As an example, translate the following Java code (a part of it, sufficient to demonstrate the technique) to C++ : public enum Planet { MERCURY (3.303e+23, 2.4397e6), VENUS (4.869e+24, 6.0518e6), EARTH (5.976e+24, 6.37814e6), MARS (6.421e+23, 3.3972e6), JUPITER (1.9e+27, 7.1492e7), SATURN (5.688e+26, 6.0268e7), URANUS (8.686e+25, 2.5559e7), NEPTUNE (1.024e+26, 2.4746e7); private final double mass; // in kilograms private final double radius; // in meters Planet(double mass, double radius) { this.mass = mass; this.radius = radius; } private double mass() { return mass; } private double radius() { return radius; } // universal gravitational constant (m3 kg-1 s-2) public static final double G = 6.67300E-11; double surfaceGravity() { return G * mass / (radius * radius); } double surfaceWeight(double otherMass) { return otherMass * surfaceGravity(); } public static void main(String[] args) { if (args.length != 1) { System.err.println("Usage: java Planet <earth_weight>"); System.exit(-1); } double earthWeight = Double.parseDouble(args[0]); double mass = earthWeight/EARTH.surfaceGravity(); for (Planet p : Planet.values()) System.out.printf("Your weight on %s is %f%n", p, p.surfaceWeight(mass)); } } Any hep would be greatly appreciated! Thanks!

  Read the article

• Work with files exception

  - by Xaver

  I want to create program which will tell me if a file is used or not by another processes (for example i open music or video file in multimedia player, and then i launch my program with this file name programm return "this file is being used", and when no processes uses this file program would say "this file not being used"). What classes have the .NET for solve this problem?

  Read the article

• Substitute for Iterator that is Serialization

  - by Mahmoud

  I'm working on a GWT project, and I have a bunch of Java classes that use Java Object Iterators on the server side. As I was reading through the internet...Iterators seem to not be serializable preventing me from sending them over to the client side from the server side. My question is is there an efficient way to serialize the iterator or use a substitute that might be serializable ? Many thanks!

  Read the article

• Is there a Base64Stream for .NET? where?

  - by Cheeso

  If I want to produce a Base64-encoded output, how would I do that in .NET? I know that since .NET 2.0, there is the ICryptoTransform interface, and the ToBase64Transform() and FromBase64Transform() implementations of that interface. But those classes are embedded into the System.Security namespace, and require the use of a TransformBlock, TransformFinalBlock, and so on. Is there an easier way to base64 encode a stream of data in .NET?

  Read the article

• Which Exception class to choose

  - by PaN1C_Showt1Me

  Suppose you want to throw Exception like this: 'Project with the provided ID cannot be assigned.' and you don't want to write your custom Exception class. What predefined Exception class would you use for this? (I'm talking about all classes inheriting from Exception)

  Read the article

• Using jQuery to disable CSS inheritance

  - by Buzzedword

  Is there a way to use jQuery (or generic javascript) to disable CSS inheritance on a block level? For example, if I am pulling in an external resource via javascript, say pastie.org, they will have their own CSS that my CSS overrides. I would like to place the embed code into its own container that has CSS inheritance disabled. This is not my own CSS structure, so I can't rename IDs Classes or inline anything to make it work, the holy grail of inheritance blocking is my last resort.

  Read the article

• Difficulty porting raw PCM output code from Java to Android AudioTrack API.

  - by IndigoParadox

  I'm attempting to port an application that plays chiptunes (NSF, SPC, etc) music files from Java SE to Android. The Android API seems to lack the javax multimedia classes that this application uses to output raw PCM audio. The closest analog I've found in the API is AudioTrack and so I've been wrestling with that. However, when I try to run one of my sample music files through my port-in-progress, all I get back is static. My suspicion is that it's the AudioTrack I've setup which is at fault. I've tried various different constructors but it all just outputs static in the end. The DataLine setup in the original code is something like: AudioFormat audioFormat = new AudioFormat( AudioFormat.Encoding.PCM_SIGNED, 44100, 16, 2, 4, 44100, true ); DataLine.Info lineInfo = new DataLine.Info( SourceDataLine.class, audioFormat ); DataLine line = (SourceDataLine)AudioSystem.getLine( lineInfo ); The constructor I'm using right now is: AudioTrack = new AudioTrack( AudioManager.STREAM_MUSIC, 44100, AudioFormat.CHANNEL_CONFIGURATION_STEREO, AudioFormat.ENCODING_PCM_16BIT, AudioTrack.getMinBufferSize( 44100, AudioFormat.CHANNEL_CONFIGURATION_STEREO, AudioFormat.ENCODING_PCM_16BIT ), AudioTrack.MODE_STREAM ); I've replaced constants and variables in those so they make sense as concisely as possible, but my basic question is if there are any obvious problems in the assumptions I made when going from one format to the other.

  Read the article

• C# - Dynamic Keyword and Interface Implementations

  - by Adam Driscoll

  I'm assuming this isn't possible but before digging further is there a way to do something like this: public void ProcessInterface(ISomeInterface obj) {} //... dynamic myDyn = GetDynamic<ISomeInterface>() ProcessInterface(myDyn); I've seen a post arguing for it but it sounds like it wasn't included. A little context: .Net assembly exposed through COM - Silverlight app consuming interface-implementing classes. Would be nice to refer to the objects by interface. I really don't expect that this was what was intended...

  Read the article

• importing class and its function from another file

  - by user343934

  Hi everyone, I am having little problem with importing classes in python. My work flow goes like this index.py class Template: def header(): def body(): def form(): def footer(): display.py I want to call function header(), body() and footer () in my display.py page. Will anyone make me clear about this issue in python. Thanks for your concern.

  Read the article

• AutoGen DB models for ASP .NET

  - by Tereno

  Hi there, I am wondering if there's anything out there for ASP .NET that is similar to Django or Ruby on Rails. Specifically, I'm looking for something that allows me to auto-generate the database models by specifying my classes in the controller and what not. Would I be able to achieve those functionality with IronPython or IronRuby? Thanks!

  Read the article

• User defined literal arguments are not constexpr?

  - by Pubby

  I'm testing out user defined literals. I want to make _fac return the factorial of the number. Having it call a constexpr function works, however it doesn't let me do it with templates as the compiler complains that the arguments are not and cannot be constexpr. I'm confused by this - aren't literals constant expressions? The 5 in 5_fac is always a literal that can be evaluated during compile time, so why can't I use it as such? First method: constexpr int factorial_function(int x) { return (x > 0) ? x * factorial_function(x - 1) : 1; } constexpr int operator "" _fac(unsigned long long x) { return factorial_function(x); // this works } Second method: template <int N> struct factorial { static const unsigned int value = N * factorial<N - 1>::value; }; template <> struct factorial<0> { static const unsigned int value = 1; }; constexpr int operator "" _fac(unsigned long long x) { return factorial_template<x>::value; // doesn't work - x is not a constexpr }

  Read the article

• Why Enumerable.Range is faster than a direct yield loop?

  - by Morgan Cheng

  Below code is checking performance of three different ways to do same solution. public static void Main(string[] args) { // for loop { Stopwatch sw = Stopwatch.StartNew(); int accumulator = 0; for (int i = 1; i <= 100000000; ++i) { accumulator += i; } sw.Stop(); Console.WriteLine("time = {0}; result = {1}", sw.ElapsedMilliseconds, accumulator); } //Enumerable.Range { Stopwatch sw = Stopwatch.StartNew(); var ret = Enumerable.Range(1, 100000000).Aggregate(0, (accumulator, n) => accumulator + n); sw.Stop(); Console.WriteLine("time = {0}; result = {1}", sw.ElapsedMilliseconds, ret); } //self-made IEnumerable<int> { Stopwatch sw = Stopwatch.StartNew(); var ret = GetIntRange(1, 100000000).Aggregate(0, (accumulator, n) => accumulator + n); sw.Stop(); Console.WriteLine("time = {0}; result = {1}", sw.ElapsedMilliseconds, ret); } } private static IEnumerable<int> GetIntRange(int start, int count) { int end = start + count; for (int i = start; i < end; ++i) { yield return i; } } } The result is like this: time = 306; result = 987459712 time = 1301; result = 987459712 time = 2860; result = 987459712 It is not surprising that "for loop" is faster than the other two solutions, because Enumerable.Aggregate takes more method invocations. However, it really surprises that "Enumerable.Range" is faster than the "self-made IEnumerable". I thought that Enumerable.Range will take more overhead than the simple GetIntRange method. What is the possible reason for this?

  Read the article

• building list of child objects inside main object

  - by Asdfg

  I have two tables like this: Category: Id Name ------------------ 1 Cat1 2 Cat2 Feature: Id Name CategoryId -------------------------------- 1 F1 1 2 F2 1 3 F3 2 4 F4 2 5 F5 2 In my .Net classes, i have two POCO classes like this: public class Category { public int Id {get;set;} public int Name {get;set;} public IList<Feature> Features {get;set;} } public class Feature { public int Id {get;set;} public int CategoryId {get;set;} public int Name {get;set;} } I am using a stored proc that returns me a result set by joining these 2 tables. This is how my Stored Proc returns the result set. SELECT c.CategoryId, c.Name Category, f.FeatureId, f.Name Feature FROM Category c INNER JOIN Feature f ON c.CategoryId = f.CategoryId ORDER BY c.Name --Resultset produced by the above query CategoryId CategoryName FeatureId FeatureName --------------------------------------------------- 1 Cat1 1 F1 1 Cat1 2 F2 2 Cat2 3 F3 2 Cat2 4 F4 2 Cat2 5 F5 Now if i want to build the list of categories in my .Net code, i have to loop thru the result set and add features unless the category changes. This is how my .Net code looks like that builds Categories and Features. List<Category> categories = new List<Category>(); Int32 lastCategoryId = 0; Category c = new Category(); using (SqlDataReader reader = cmd.ExecuteReader()) { while (reader.Read()) { //Check if the categoryid is same as previous one. //If Not, add new category. //If Yes, dont add the category. if (lastCategoryId != Convert.ToInt32(reader["CategoryId"])) { c = new Category { Id = Convert.ToInt32(reader["CategoryId"]), Name = reader["CategoryName"].ToString() }; c.Features = new List<Feature>(); categories.Add(c); } lastCategoryId = Convert.ToInt32(reader["CategoryId"]); //Add Feature c.Features.Add(new Feature { Name = reader["FeatureName"].ToString(), Id = Convert.ToInt32(reader["FeatureId"]) }); } return categories; } I was wondering if there is a better way to do build the list of Categories?

  Read the article

• xcode project-/target-settings-syntax for linker flag force_load on iPhone

  - by Kaiserludi

  Hi all. I am confronted with the double bind, that on the one hand for one of the 3rd party static libraries, my iPhone application uses, the linker flag -all_load has to be set in the application project- or target settings, otherwise the app crashes at runtime not finding some symbols, called internally from the lib, on the other hand for another 3rd party static lib -all_load must not be set on application level, or the app won't build thanks to a "duplicate symbols"-linker error. To solve this issue I now want to use force_load instant of load_all, as it due to documentation it does the same like all_load, but only for the passed path or lib-file, instead of all libs. The problem with force_load is, I do not have a clue, how to pass a path or file as parameter with it, when passing it via xcode project- or target-settings. All syntax-possibilities coming to my mind either lead into xcode thinking its another linker flag instead of a parameter to the previous one, or the linker is throwing syntax related errors or the flag simply does nothing at all in comparison to not being set. I also opened the .pbxproj-file in a text-editor to edit it to the correct command line syntax manually, but when reloading the project with xcode, it auto changes the syntax into interpreting the parameter to force_load as a separate flag. Anyone having an idea on this issue? Thx, Kaiserludi.

  Read the article

• Recursion in prepared statements

  - by Rob

  I've been using PDO and preparing all my statements primarily for security reasons. However, I have a part of my code that does execute the same statement many times with different parameters, and I thought this would be where the prepared statements really shine. But they actually break the code... The basic logic of the code is this. function someFunction($something) { global $pdo; $array = array(); static $handle = null; if (!$handle) { $handle = $pdo->prepare("A STATEMENT WITH :a_param"); } $handle->bindValue(":a_param", $something); if ($handle->execute()) { while ($row = $handle->fetch()) { $array[] = someFunction($row['blah']); } } return $array; } It looked fine to me, but it was missing out a lot of rows. Eventually I realised that the statement handle was being changed (executed with different param), which means the call to fetch in the while loop will only ever work once, then the function calls itself again, and the result set is changed. So I am wondering what's the best way of using PDO prepared statements in a recursive way. One way could be to use fetchAll(), but it says in the manual that has a substantial overhead. The whole point of this is to make it more efficient. The other thing I could do is not reuse a static handle, and instead make a new one every time. I believe that since the query string is the same, internally the MySQL driver will be using a prepared statement anyway, so there is just the small overhead of creating a new handle on each recursive call. Personally I think that defeats the point. Or is there some way of rewriting this?

  Read the article

• JavaFX: File upload to REST service / servlet fails because of missing boundary

  - by spa

  I'm trying to upload a file using JavaFX using the HttpRequest. For this purpose I have written the following function. function uploadFile(inputFile : File) : Void { // check file if (inputFile == null or not(inputFile.exists()) or inputFile.isDirectory()) { return; } def httpRequest : HttpRequest = HttpRequest { location: urlConverter.encodeURL("{serverUrl}"); source: new FileInputStream(inputFile) method: HttpRequest.POST headers: [ HttpHeader { name: HttpHeader.CONTENT_TYPE value: "multipart/form-data" } ] } httpRequest.start(); } On the server side, I am trying to handle the incoming data using the Apache Commons FileUpload API using a Jersey REST service. The code used to do this is a simple copy of the FileUpload tutorial on the Apache homepage. @Path("Upload") public class UploadService { public static final String RC_OK = "OK"; public static final String RC_ERROR = "ERROR"; @POST @Produces("text/plain") public String handleFileUpload(@Context HttpServletRequest request) { if (!ServletFileUpload.isMultipartContent(request)) { return RC_ERROR; } FileItemFactory factory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(factory); List<FileItem> items = null; try { items = upload.parseRequest(request); } catch (FileUploadException e) { e.printStackTrace(); return RC_ERROR; } ... } } However, I get a exception at items = upload.parseRequest(request);: org.apache.commons.fileupload.FileUploadException: the request was rejected because no multipart boundary was found I guess I have to add a manual boundary info to the InputStream. Is there any easy solution to do this? Or are there even other solutions?

  Read the article

• Possible to write an Extension Method for ASP.NET's Html.ActionLink() method?

  - by Pretzel

  Right now, I'm trying to work around an IE6/7 bug which requires the wrapping of the </a closing tag with this IE specific comment to make some drop-down menu work: <!--[if IE 7]><!--></a><!--<![endif]--> Unfortunately, I cannot inject this directly into my View page code like this: <%= Html.ActionLink("LinkName<!--[if IE 7]><!--></a><!--<![endif]-->","Action","Controller") %> As Html.ActionLink will do the safe thing and filter out the comment to prevent a Javascript injection attack. Ok, cool. I'm fine with that. Good design decision. What I'd like to do is write an Extension Method to this, but the process is eluding me as I haven't done this before. I thought this would work, but Intellisense doesn't seem to be picking up this Extension method that I've written. public static class MyLinkExtensions { public static string ActionLinkIE(this HtmlHelper htmlHelper, string linkText, string actionName, string controllerName) { return LinkExtensions.ActionLink(htmlHelper, linkText, actionName, controllerName). Replace(@"</a>", @"<!--[if IE 7]><!--></a><!--<![endif]-->"); } } Any suggestions?

  Read the article

• Google Analytics version 3 - How to apply it correctly?

  - by ephramd

  I've added google analytics to my app with the intention of obtaining information about the screens you and send custom events. I am obtained duplicate content ... Also I get different results: "com.package.app.MainScreen" - 300 views and "Main Screen" - 200 views I am interested to get only follow up with the custom name of the activity and not the package. And in any case, because both show different results? public class MainScreen extends Activity { private static final String GA_PROPERTY_ID = "UA-12345678-9"; private static final String SCREEN_LABEL = "Main Screen"; Tracker mTracker; EasyTracker easyTracker; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_screen); mTracker = GoogleAnalytics.getInstance(this).getTracker(GA_PROPERTY_ID); mTracker.set(Fields.SCREEN_NAME, SCREEN_LABEL); // For Custom Name from activity mTracker.send(MapBuilder.createAppView().build()); easyTracker = EasyTracker.getInstance(this); // Analytics Events ... easyTracker.send(MapBuilder.createEvent("MainScreen", "Play", category.get(1), null).build()); //AnalyticsEvents ... } @Override public void onStart() { super.onStart(); EasyTracker.getInstance(this).activityStart(this); } @Override public void onStop() { super.onStop(); EasyTracker.getInstance(this).activityStop(this); } } And analytics.xml: <?xml version="1.0" encoding="utf-8" ?> <resources xmlns:tools="http://schemas.android.com/tools" tools:ignore="TypographyDashes"> <!--Replace placeholder ID with your tracking ID--> <string name="ga_trackingId">UA-12345678-9</string> <!--Enable automatic activity tracking--> <bool name="ga_autoActivityTracking">true</bool> <!--Enable automatic exception tracking--> <bool name="ga_reportUncaughtExceptions">true</bool> </resources> Google Analytics Dev Guide

  Read the article

• Can this extension method be improved?

  - by Newbie

  I have the following extension method public static class ListExtensions { public static IEnumerable<T> Search<T>(this ICollection<T> collection, string stringToSearch) { foreach (T t in collection) { Type k = t.GetType(); PropertyInfo pi = k.GetProperty("Name"); if (pi.GetValue(t, null).Equals(stringToSearch)) { yield return t; } } } } What it does is by using reflection, it finds the name property and then filteres the record from the collection based on the matching string. This method is being called as List<FactorClass> listFC = new List<FactorClass>(); listFC.Add(new FactorClass { Name = "BKP", FactorValue="Book to price",IsGlobal =false }); listFC.Add(new FactorClass { Name = "YLD", FactorValue = "Dividend yield", IsGlobal = false }); listFC.Add(new FactorClass { Name = "EPM", FactorValue = "emp", IsGlobal = false }); listFC.Add(new FactorClass { Name = "SE", FactorValue = "something else", IsGlobal = false }); List<FactorClass> listFC1 = listFC.Search("BKP").ToList(); It is working fine. But a closer look into the extension method will reveal that Type k = t.GetType(); PropertyInfo pi = k.GetProperty("Name"); is actually inside a foreach loop which is actually not needed. I think we can take it outside the loop. But how? PLease help. (C#3.0)

  Read the article

< Previous Page | 378 379 380 381 382 383 384 385 386 387 388 389  | Next Page >