Search Results

Search found 12141 results on 486 pages for 'basic skills'.

Page 444/486 | < Previous Page | 440 441 442 443 444 445 446 447 448 449 450 451  | Next Page >

  • PHP MVC Principles

    - by George
    I'm not using an off-the-shelf framework and don't particularly want to (nor d I want to go into the reasons why...). Anyway, onto my question(s), I hope it make sense.... I'm trying to get my head around what should go in the model and what should go in the controller. Originally I had the impression that a model class should represent an actual object (eg - a car from the cars table of a database) and model properties should mirror the database fields. However I'm now getting the feeling that I've got the wrong idea - should an instance of a model class represent an actual item, or should it contain a number of methods for doing stuff - sometimes to one car or sometimes to multiple cars based on my example earlier. For example I want to get all the cars from a the database and show them in the view. Am I right in think it should be along the lines of this? Controller File function list() { $cars = $this->model->get_all(); $this->view->add($cars); $this->view->render('cars-list'); } Model File function get_all() { // Use a database interaction class that I've written $cars = Database::select(); return $cars; } Now, if the car had a "status" field that was stored as an integer in the database and I wanted to change that to a string, where should that be done? By looping the SQL results array in the get_all() method in the model? Also, where should form validation live? I have written a validation class that works a little like this: $validator = new Validator(); $validator->check('field_name', 'required'); If the check fails, it adds an error message to the array in the Validator. This array of error messages would then get passed to the view. Should the use of my validator class go in model or the controller? Thanks in advance for for any help anyone can offer. If you know of any links to a simple MVC example / open source application that deals with basic CRUD, they would be much appreciated.

    Read the article

  • C++ Unlocking a std::mutex before calling std::unique_lock wait

    - by Sant Kadog
    I have a multithreaded application (using std::thread) with a manager (class Tree) that executes some piece of code on different subtrees (embedded struct SubTree) in parallel. The basic idea is that each instance of SubTree has a deque that store objects. If the deque is empty, the thread waits until a new element is inserted in the deque or the termination criteria is reached. One subtree can generate objects and push them in the deque of another subtree. For convenience, all my std::mutex, std::locks and std::variable_condition are stored in a struct called "locks". The class Tree creates some threads that run the following method (first attempt) : void Tree::launch(SubTree & st, Locks & locks ) { /* some code */ std::lock_guard<std::mutex> deque_lock(locks.deque_mutex_[st.id_]) ; // lock the access to the deque of subtree st if (st.deque_.empty()) // check that the deque is still empty { // some threads are still running, wait for them to terminate std::unique_lock<std::mutex> wait_lock(locks.restart_mutex_[st.id_]) ; locks.restart_condition_[st.id_].wait(wait_lock) ; } /* some code */ } The problem is that "deque_lock" is still locked while the thread is waiting. Hence no object can be added in the deque of the current thread by a concurrent one. So I turned the lock_guard into a unique_lock and managed the lock/unlock manually : void launch(SubTree & st, Locks & locks ) { /* some code */ std::unique_lock<std::mutex> deque_lock(locks.deque_mutex_[st.id_]) ; // lock the access to the deque of subtree st if (st.deque_.empty()) // check that the deque is still empty { deque_lock.unlock() ; // unlock the access to the deque to enable the other threads to add objects // DATA RACE : nothing must happen to the unprotected deque here !!!!!! // some threads are still running, wait for them to terminate std::unique_lock<std::mutex> wait_lock(locks.restart_mutex_[st.id_]) ; locks.restart_condition_[st.id_].wait(wait_lock) ; } /* some code */ } The problem now, is that there is a data race, and I would like to make sure that the "wait" instruction is performed directly after the "deque_lock.unlock()" one. Would anyone know a way to create such a critical instruction sequence with the standard library ? Thanks in advance.

    Read the article

  • How to group items by date range in XSLT?

    - by glenatron
    I have a bunch of data that looks a little like this: <item> <colour>Red</colour> <date_created>2009-10-10 12:01:55</date_created> <date_sold>2009-10-20 22:32:12</date_sold> </item> <item> <colour>Blue</colour> <date_created>2009-11-01 13:21:00</date_created> <date_sold>2009-11-21 12:32:12</date_sold> </item> <item> <colour>Blue</colour> <date_created>2009-10-29 21:23:02</date_created> <date_sold>2009-10-20 02:02:22</date_sold> </item> <item> <colour>Red</colour> <date_created>2009-11-02 09:11:51</date_created> <date_sold>2009-11-20 09:15:53</date_sold> </item> <item> <colour>Red</colour> <date_created>2009-10-18 11:00:55</date_created> <date_sold>2009-10-20 11:12:22</date_sold> </item> Now what I would like to be able to do is to run that through an XSLT stylesheet such that I get ouput looking like this: Colour | In stock 1 week | In stock 2 weeks | In stock 3 weeks Red | 1 | 3 | 2 Blue | 0 | 2 | 1 Currently I have a stylesheet that uses basic muenchian grouping to show that 30% of stock was Red and 70% blue, but I can't see a way to find the number of nodes withing a given date range. Is there a way to use keys to select a range? Do I need to create some kind of intermediate data node? Is there a different route that shows I'm barking up the wrong tree with both those suggestions? Is this even possible with XSLT or do I need to find a way to change the data source?

    Read the article

  • Asynchronous Silverlight 4 call to the World of Warcraft armoury streaming XML in C#

    - by user348446
    Hello - I have been stuck on this all weekend and failed miserably! Please help me to claw back my sanity!! Your challenge For my first Silverlight application I thought it would be fun to use the World of Warcraft armoury to list the characters in my guild. This involves making an asyncronous from Silverlight (duh!) to the WoW armoury which is XML based. SIMPLE EH? Take a look at this link and open the source. You'll see what I mean: http://eu.wowarmory.com/guild-info.xml?r=Eonar&n=Gifted and Talented Below is code for getting the XML (the call to ShowGuildies will cope with the returned XML - I have tested this locally and I know it works). I have not managed to get the expected returned XML at all. Notes: If the browser is capable of transforming the XML it will do so, otherwise HTML will be provided. I think it examines the UserAgent I am a seasoned asp.net web developer C# so go easy if you start talking about native to Windows Forms / WPF I can't seem to set the UserAgent setting in .net 4.0 - doesn't seem to be a property off the HttpWebRequest object for some reason - i think it used to be available. Silverlight 4.0 (created as 3.0 originally before I updated my installation of Silverlight to 4.0) Created using C# 4.0 Please explain as if you talking to a web developer and not a proper programming lol! Below is the code - it should return the XML from the wow armoury. private void button7_Click(object sender, RoutedEventArgs e) { // URL for armoury lookup string url = @"http://eu.wowarmory.com/guild-info.xml?r=Eonar&n=Gifted and Talented"; // Create the web request HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url); // Set the user agent so we are returned XML and not HTML //httpWebRequest.Headers["User-Agent"] = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0)"; // Not sure about this dispatcher thing - it's late so i have started to guess. Dispatcher.BeginInvoke(delegate() { // Call asyncronously IAsyncResult asyncResult = httpWebRequest.BeginGetResponse(ReqCallback, httpWebRequest); // End the response and use the result using (HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.EndGetResponse(asyncResult)) { // Load an XML document from a stream XDocument x = XDocument.Load(httpWebResponse.GetResponseStream()); // Basic function that will use LINQ to XML to get the list of characters. ShowGuildies(x); } }); } private void ReqCallback(IAsyncResult asynchronousResult) { // Not sure what to do here - maybe update the interface? } Really hope someone out there can help me! Thanks mucho! Dan. PS Yes, I have noticed the irony in the name of the guild :)

    Read the article

  • jQuery: Sort div's according to content of different sub divs

    - by rayne
    I'm trying to create a somewhat complex sorting feature which neither uses divs nor lists. Unfortunately two hours of googling didn't help me. Here is the basic setup of my HTML: <div id="all_elements"> <!-- one element --> <div class="element"> <div class="wrapper"> <a href="/" title="links"> <img src="/img/image.jpg" border="0" alt="image" class="image" /></a> <div class="details"> <h3><a href="/" title="title">Name (Sort Argument 1)</a></h3> <div class="title"><a href="/" title="title">Title (Sort Argument 2)</a></div> <div class="year">2010 (Sort Argumentt 3)</div> <div class="country">Great Britain (Sort Argument 4)</div> </div><!-- details --> </div><!-- wrapper --> </div><!-- element --> </div> <!--all_elements--> The setup is a bit complex, but basically .element is the element that needs to be sorted alphabetically according to either the contents of h3, div.title, div.year or div.country. So the user will be able to view the contents of the site either sorted by name, by year, by country or by title. I have this jQuery snippet from a website, but all my attempts on trying to tell it to use the contents of e.g. h3 to sort have failed. Right now it sorts pretty much randomly. jQuery.fn.sort = function() { return this.pushStack([].sort.apply(this, arguments), []); }; function sortAscending(a, b) { return a.innerHTML > b.innerHTML ? 1 : -1; }; function sortDescending(a, b) { return a.innerHTML < b.innerHTML ? 1 : -1; }; $(document).ready(function() { $("#sort").toggle( function() { $('#all_elements .element').sort(sortDescending).appendTo('#all_elements'); $(this).text("Sort Asc"); }, function() { $('#all_elements .element').sort(sortAscending).appendTo('#all_elements'); $(this).text("Sort Desc"); }); }); How can I customize the function to sort the contents of my h3 or divs?

    Read the article

  • How can I limit the cache used by copying so there is still memory available for other cache?

    - by Peter
    Basic situation: I am copying some NTFS disks in openSuSE. Each one is 2TB. When I do this, the system runs slow. My guesses: I believe it is likely due to caching. Linux decides to discard useful cache (eg. kde4 bloat, virtual machine disks, LibreOffice binaries, Thunderbird binaries, etc.) and instead fill all available memory (24 GB total) with stuff from the copying disks, which will be read only once, then written and never used again. So then any time I use these apps (or kde4), the disk needs to be read again, and reading the bloat off the disk again makes things freeze/hiccup. Due to the cache being gone and the fact that these bloated applications need lots of cache, this makes the system horribly slow. Since it is USB,the disk and disk controller are not the bottleneck, so using ionice does not make it faster. I believe it is the cache rather than just the motherboard going too slow, because if I stop everything copying, it still runs choppy for a while until it recaches everything. And if I restart the copying, it takes a minute before it is choppy again. But also, I can limit it to around 40 MB/s, and it runs faster again (not because it has the right things cached, but because the motherboard busses have lots of extra bandwidth for the system disks). I can fully accept a performance loss from my motherboard's IO capability being completely consumed (which is 100% used, meaning 0% wasted power which makes me happy), but I can't accept that this caching mechanism performs so terribly in this specific use case. # free total used free shared buffers cached Mem: 24731556 24531876 199680 0 8834056 12998916 -/+ buffers/cache: 2698904 22032652 Swap: 4194300 24764 4169536 I also tried the same thing on Ubuntu, which causes a total system hang instead. ;) And to clarify, I am not asking how to leave memory free for the "system", but for "cache". I know that cache memory is automatically given back to the system when needed, but my problem is that it is not reserved for caching of specific things. Question: Is there some way to tell these copy operations to limit memory usage so some important things remain cached, and therefore any slowdowns are a result of normal disk usage and not rereading the same commonly used files? For example, is there a setting of max memory per process/user/file system allowed to be used as cache/buffers?

    Read the article

  • Undesired "flashing" in Jquery dropdown menu?

    - by Tom
    Hi, I've got the following piece of Jquery: $("#collapse-menu > li > a").click(function() { $(this).toggleClass("expanded").toggleClass("collapsed").find("+ ul").slideToggle("medium"); }); What it basically does is expands or collapses a menu of nested "lists" which contain dropdowns (simplified example): <ul id="collapse-menu"> <li><a class="expanded">Basic Details</a> <ul> <li> <select> .... </select> </li> <li> <select> .... </select> </li> The code works absolutely fine EXCEPT when a large value is selected in any of the dropdowns. At that point, when clicked, the menu will still expand/collapse correctly but "flash" quickly while doing so, as if the entire element was being reset somehow. The data itself is fine but it's the flashing that's unwanted. The strange thing is that if a small value is selected in a dropdown, there's no flashing. When a large value is selected (say, above 30 in an age dropdown of 18-99), the flashing starts happening. Can anyone tell me why this is happening? Or whether there's something not right about the Jquery that's causing this. Thanks. UPDATE: Adding a bounty to this. Have tried a few similar plugins/solutions out there on the net but they all seem to suffer from this "flashing" problem when large dropdown values are selected by default. If it helps, here's a typical similar solution: http://www.i-marco.nl/weblog/jquery-accordion-menu/index_collapsed.html# ... but it suffers from the same problem when dropdowns are added inside the accordion. I hope someone has a clean solution, instead of needing to hack this somehow.

    Read the article

  • Python4Delphi: Returning a python object in a function. (DelphiWrapper)

    - by Gabriel Fonseca
    I am using python4delphi. ow can I return an object from a wrapped Delphi class function? Code Snippet: I have a simple Delphi Class that i wrapped to Python Script, right? TSimple = Class Private function getvar1:string; Public Published property var1:string read getVar1; function getObj:TSimple; end; ... function TSimple.getVar1:string; begin result:='hello'; end; function TSimple.getObj:TSimple; begin result:=self; end; I made the TPySimple like the demo32 to give class access to the python code. My python module name is test. TPyDado = class(TPyDelphiPersistent) // Constructors & Destructors constructor Create( APythonType : TPythonType ); override; constructor CreateWith( PythonType : TPythonType; args : PPyObject ); override; // Basic services function Repr : PPyObject; override; class function DelphiObjectClass : TClass; override; end; ... { TPyDado } constructor TPyDado.Create(APythonType: TPythonType); begin inherited; // we need to set DelphiObject property DelphiObject := TDado.Create; with TDado(DelphiObject) do begin end; Owned := True; // We own the objects we create end; constructor TPyDado.CreateWith(PythonType: TPythonType; args: PPyObject); begin inherited; with GetPythonEngine, DelphiObject as TDado do begin if PyArg_ParseTuple( args, ':CreateDado' ) = 0 then Exit; end; end; class function TPyDado.DelphiObjectClass: TClass; begin Result := TDado; end; function TPyDado.Repr: PPyObject; begin with GetPythonEngine, DelphiObject as TDado do Result := VariantAsPyObject(Format('',[])); // or Result := PyString_FromString( PAnsiChar(Format('(%d, %d)',[x, y])) ); end; And now the python code: import test a = test.Simple() # try access the property var1 and everything is right print a.var1 # work's, but.. b = a.getObj(); # raise a exception that not find any attributes named getObj. # if the function returns a string for example, it's work.

    Read the article

  • Dependency Injection and Unit of Work pattern

    - by sunwukung
    I have a dilemma. I've used DI (read: factory) to provide core components for a homebrew ORM. The container provides database connections, DAO's,Mappers and their resultant Domain Objects on request. Here's a basic outline of the Mappers and Domain Object classes class Mapper{ public function __constructor($DAO){ $this->DAO = $DAO; } public function load($id){ if(isset(Monitor::members[$id]){ return Monitor::members[$id]; $values = $this->DAO->selectStmt($id); //field mapping process omitted for brevity $Object = new Object($values); return $Object; } } class User(){ public function setName($string){ $this->name = $string; //mark modified by means fair or foul } } The ORM also contains a class (Monitor) based on the Unit of Work pattern i.e. class Monitor(){ private static array modified; private static array dirty; public function markClean($class); public function markModified($class); } The ORM class itself simply co-ordinates resources extracted from the DI container. So, to instantiate a new User object: $Container = new DI_Container; $ORM = new ORM($Container); $User = $ORM->load('user',1); //at this point the container instantiates a mapper class //and passes a database connection to it via the constructor //the mapper then takes the second argument and loads the user with that id $User->setName('Rumpelstiltskin');//at this point, User must mark itself as "modified" My question is this. At the point when a user sets values on a Domain Object class, I need to mark the class as "dirty" in the Monitor class. I have one of three options as I can see it 1: Pass an instance of the Monitor class to the Domain Object. I noticed this gets marked as recursive in FirePHP - i.e. $this-Monitor-markModified($this) 2: Instantiate the Monitor directly in the Domain Object - does this break DI? 3: Make the Monitor methods static, and call them from inside the Domain Object - this breaks DI too doesn't it? What would be your recommended course of action (other than use an existing ORM, I'm doing this for fun...)

    Read the article

  • Formatting Controls in ASP.NET

    - by Brian
    I feel as though this this is a simple question, but can't find an answer anywhere. We've got an interface we're trying to move to an ASP.NET control. It currently looks like: <link rel=""stylesheet"" type=""text/css"" href=""/Layout/CaptchaLayout.css"" /> <script type=""text/javascript"" src=""../../Scripts/vcaptcha_control.js""></script> <div id="captcha_background"> <div id="captcha_loading_area"> <img id="captcha" src="#" alt="" /> </div> <div id="vcaptcha_entry_container"> <input id="captcha_answer" type="text"/> <input id="captcha_challenge" type="hidden"/> <input id="captcha_publickey" type="hidden"/> <input id="captcha_host" type="hidden"/> </div> <div id="captcha_logo_container"></div> </div> However all the examples I see of ASP.NET controls that allow for basical functionality - i.e. public class MyControl : Panel { public MyControl() { } protected override void OnInit(EventArgs e) { ScriptManager.RegisterScript( ... Google script, CSS, etc. ... ); TextBox txt = new TextBox(); txt.ID = "text1"; this.Controls.Add(txt); CustomValidator vld = new CustomValidator(); vld.ControlToValidate = "text1"; vld.ID = "validator1"; this.Controls.Add(vld); } } Don't allow for the detailed layout that we need. Any suggestions on how I can combine layout and functionality and still have a single ASP control we can drop in to pages? The ultimate goal is for users of the control to just drop in: <captcha:CaptchaControl ID="CaptchaControl1" runat="server" Server="http://localhost:51947/" /> and see the working control. Sorry for the basic nature of this one, any help is greatly appreciated.

    Read the article

  • Access Denied Java FileWriter / FileInputStream

    - by Matt
    My program downloads a websites source code, modifies it, creates the file, and then reuploads it through the FTP. However, I receive the following error when trying to open the created file: java.io.FileNotFoundException: misc.html (Access is denied) at java.io.FileInputStream.open(Native Method) at java.io.FileInputStream.<init>(Unknown Source) at Manipulator.uploadSource(Manipulator.java:63) at Start.addPicture(Start.java:130) at Start$2.actionPerformed(Start.java:83) at javax.swing.AbstractButton.fireActionPerformed(Unknown Source) at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source) at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source) at javax.swing.DefaultButtonModel.setPressed(Unknown Source) at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source) at java.awt.Component.processMouseEvent(Unknown Source) at javax.swing.JComponent.processMouseEvent(Unknown Source) at java.awt.Component.processEvent(Unknown Source) at java.awt.Container.processEvent(Unknown Source) at java.awt.Component.dispatchEventImpl(Unknown Source) at java.awt.Container.dispatchEventImpl(Unknown Source) at java.awt.Component.dispatchEvent(Unknown Source) at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source) at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source) at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source) at java.awt.Container.dispatchEventImpl(Unknown Source) at java.awt.Window.dispatchEventImpl(Unknown Source) at java.awt.Component.dispatchEvent(Unknown Source) at java.awt.EventQueue.dispatchEvent(Unknown Source) at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) at java.awt.EventDispatchThread.pumpEvents(Unknown Source) at java.awt.EventDispatchThread.pumpEvents(Unknown Source) at java.awt.EventDispatchThread.run(Unknown Source) When I navigate to the folder directory and attempt to open "misc.html" with Notepad I receive Access is Denied. My code is fairly simple: File f = new File(page.sourceFileName); try { FileWriter out = new FileWriter(f); out.write(page.source); out.close(); } catch (IOException e) { e.printStackTrace(); } InputStream input = new FileInputStream(f); This is the vital excerpt from my program. I have copied this into a different test program and it works fine, I create a misc.html file and reopen it with both FileInputStream and manually. I would be worried about Administrator rights but the Test program works fine when I run it RIGHT after the problem program. I also have checked if the file exists and is a file with File methods and it is as well. Is this a result of me not closing a previous Input/Output properly? I've tried to check everything and I am fairly positive I close all streams as soon as they finish... Help! :)

    Read the article

  • What is your most productive shortcut with Vim?

    - by Olivier Pons
    I've heard a lot about Vim, both pros and cons. It really seems you should be (as a developer) faster with Vim than with any other editor. I'm using Vim to do some basic stuff and I'm at best 10 times less productive with Vim. The only two things you should care about when you talk about speed (you may not care enough about them, but you should) are: Using alternatively left and right hands is the fastest way to use the keyboard. Never touching the mouse is the second way to be as fast as possible. It takes ages for you to move your hand, grab the mouse, move it, and bring it back to the keyboard (and you often have to look at the keyboard to be sure you returned your hand properly to the right place) Here are two examples demonstrating why I'm far less productive with Vim. Copy/Cut & paste. I do it all the time. With all the classical editors you press Shift with the left hand, and you move the cursor with your right hand to select text. Then Ctrl+C copies, you move the cursor and Ctrl+V pastes. With Vim it's horrible: yy to copy one line (you almost never want the whole line!) [number xx]yy to copy xx lines into the buffer. But you never know exactly if you've selected what you wanted. I often have to do [number xx]dd then u to undo! Another example? Search & replace. In PSPad: Ctrl+f then type what you want you search for, then press Enter. In Vim: /, then type what you want to search for, then if there are some special characters put \ before each special character, then press Enter. And everything with Vim is like that: it seems I don't know how to handle it the right way. NB : I've already read the Vim cheat sheet :) My question is: What is the way you use Vim that makes you more productive than with a classical editor?

    Read the article

  • initWithCoder works, but init seems to be overwriting my objects properties?

    - by Zigrivers
    Hi guys, I've been trying to teach myself how to use the Archiving/Unarchiving methods of NSCoder, but I'm stumped. I have a Singleton class that I have defined with 8 NSInteger properties. I am trying to save this object to disk and then load from disk as needed. I've got the save part down and I have the load part down as well (according to NSLogs), but after my "initWithCoder:" method loads the object's properties appropriately, the "init" method runs and resets my object's properties back to zero. I'm probably missing something basic here, but would appreciate any help! My class methods for the Singleton class: + (Actor *)shareActorState { static Actor *actorState; @synchronized(self) { if (!actorState) { actorState = [[Actor alloc] init]; } } return actorState; } -(id)init { if (self = [super init]) { NSLog(@"New Init for Actor started...\nStrength: %d", self.strength); } return self; } -(id)initWithCoder:(NSCoder *)coder { if (self = [super init]) { strength = [coder decodeIntegerForKey:@"strength"]; dexterity = [coder decodeIntegerForKey:@"dexterity"]; stamina = [coder decodeIntegerForKey:@"stamina"]; will = [coder decodeIntegerForKey:@"will"]; intelligence = [coder decodeIntegerForKey:@"intelligence"]; agility = [coder decodeIntegerForKey:@"agility"]; aura = [coder decodeIntegerForKey:@"aura"]; eyesight = [coder decodeIntegerForKey:@"eyesight"]; NSLog(@"InitWithCoder executed....\nStrength: %d\nDexterity: %d", self.strength, self.dexterity); [self retain]; } return self; } -(void) encodeWithCoder:(NSCoder *)encoder { [encoder encodeInteger:strength forKey:@"strength"]; [encoder encodeInteger:dexterity forKey:@"dexterity"]; [encoder encodeInteger:stamina forKey:@"stamina"]; [encoder encodeInteger:will forKey:@"will"]; [encoder encodeInteger:intelligence forKey:@"intelligence"]; [encoder encodeInteger:agility forKey:@"agility"]; [encoder encodeInteger:aura forKey:@"aura"]; [encoder encodeInteger:eyesight forKey:@"eyesight"]; NSLog(@"encodeWithCoder executed...."); } -(void)dealloc { //My dealloc stuff goes here [super dealloc]; } I'm a noob when it comes to this stuff and have been trying to teach myself for the last month, so forgive anything obvious. Thanks for the help!

    Read the article

  • do I need to close an audio Clip?

    - by Michael
    have an application that processes real-time data and is supposed to beep when a certain event occurs. The triggering event can occur multiple times per second, and if the beep is already playing when another event triggers the code is just supposed to ignore it (as opposed to interrupting the current beep and starting a new one). Here is the basic code: Clip clickClip public void prepareProcess() { super.prepareProcess(); clickClip = null; try { clipFile = new File("C:/WINDOWS/Media/CHIMES.wav"); ais = AudioSystem.getAudioInputStream(clipFile); clickClip = AudioSystem.getClip(); clickClip.open(ais); fileIsLoaded = true; } catch (Exception ex) { clickClip = null; fileIsLoaded = false; } } public void playSound() { if (fileIsLoaded) { if ((clickClip==null) || (!clickClip.isRunning())) { try { clickClip.setFramePosition(0); clickClip.start(); } catch (Exception ex) { System.out.println("Cannot play click noise"); ex.printStackTrace(); } } } The prepareProcess method gets run once in the beginning, and the playSound method is called every time a triggering event occurs. My question is: do I need to close the clickClip object? I know I could add an actionListener to monitor for a Stop event, but since the event occurs so frequently I'm worried the extra processing is going to slow down the real-time data collection. The code seems to run fine, but my worry is memory leaks. The code above is based on an example I found while searching the net, but the example used an actionListener to close the Clip specifically "to eliminate memory leaks that would occur when the stop method wasn't implemented". My program is intended to run for hours so any memory leaks I have will cause problems. I'll be honest: I have no idea how to verify whether or not I've got a problem. I'm using Netbeans, and running the memory profiler just gave me a huge list of things that I don't know how to read. This is supposed to be the simple part of the program, and I'm spending hours on it. Any help would be greatly appreciated! Michael

    Read the article

  • Which MarkDown (WMD) javascript editor should I use?

    - by Edan Maor
    Background I'm working on an application which requires user-entered content, and I've decided to use a StackOverflow-style MarkDown editor. After researching this topic for the last few days, I realize there are numerous forks of the base WMD editor, some with a few basic enhancements and some with serious differences from the StackOverflow one. Since this will be the heart of the application, I'd like to start with the best code base I can. I'd be happy if anyone can recommend which one of the many solutions out there best fits my needs. Below is requirements, plus what I've managed to find already. I'm hoping this question will help me decide which version to go with, and maybe help me discover a port out there that's an even better fit for my needs. The requirements for my project Live Preview Multiple editors on the same page (not know how many in advance, since the user can dynamically add another editing box). Ability to extend with extra buttons (I'd like a button to upload a picture, instead of just adding an img url). Ability to dynamically show/hide the edit box (and only see the preview box). Not an absolute must, but I'd prefer to stick as close to StackOverflow's look and feel, since it's well known. Don't know if this matters, but the backend is written in Django. Editors I've looked at Here are a few of the code bases I've looked at, with thoughts. Obviously, I might be missing another solution out there. The derobins version. From what I can tell, this is the official StackOverflow version. Seems like it doesn't support multiple editors on one page. JQuery.MarkEdit. Looks very good, but is pretty different from the StackOverflow version. MooWMD. Looks like the winner right now, but I'm a little concerned since it looks less active/hackable than MarkEdit. The wmd-new version. Not sure, looks like an old codebase without much use. The SocialSite branch. Seems like it's not for public use.

    Read the article

  • Error trying to run rails server

    - by David87
    I am trying to get a basic Rails application to run on my Mac OS X 10.6.5. I created a new app called demo (rails new demo), then went into the demo directory and tried to start the app with rails server. Here is the error message I received: "/Users/dpetrovi/.gem/ruby/1.8/gems/sqlite3-ruby-1.3.2/lib/sqlite3/sqlite3_native.bundle: [BUG] Segmentation fault ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10] Abort trap" I checked bundle install in the demo folder: "Using rake (0.8.7) Using abstract (1.0.0) Using activesupport (3.0.3) Using builder (2.1.2) Using i18n (0.5.0) Using activemodel (3.0.3) Using erubis (2.6.6) Using rack (1.2.1) Using rack-mount (0.6.13) Using rack-test (0.5.6) Using tzinfo (0.3.23) Using actionpack (3.0.3) Using mime-types (1.16) Using polyglot (0.3.1) Using treetop (1.4.9) Using mail (2.2.13) Using actionmailer (3.0.3) Using arel (2.0.6) Using activerecord (3.0.3) Using activeresource (3.0.3) Using bundler (1.0.7) Using thor (0.14.6) Using railties (3.0.3) Using rails (3.0.3) Using sqlite3-ruby (1.3.2) Your bundle is complete! Use bundle show [gemname] to see where a bundled gem is installed." Ruby, RubyGems, and sqlite3 were installed using MacPorts. Then I used gem to try to install the sqlite3-ruby interface. (sudo gem install sqlite3-ruby). Here is where I first noticed something could be off: "Successfully installed sqlite3-ruby-1.3.2 1 gem installed Installing ri documentation for sqlite3-ruby-1.3.2... No definition for libversion Enclosing class/module 'mSqlite3' for class Statement not known Installing RDoc documentation for sqlite3-ruby-1.3.2... No definition for libversion Enclosing class/module 'mSqlite3' for class Statement not known " I had rails running well on my system a few months ago, so I figured maybe I had some duplicates and it was trying to use the wrong one. I ran: "for cmd in ruby irb gem rake; do which $cmd; done" and got: "/opt/local/bin/ruby /opt/local/bin/irb /opt/local/bin/gem /opt/local/bin/rake" Checking where sqlite3 also gets me: "/opt/local/bin/sqlite3" so they all seem to be in the right place. Obviously /opt/local/bin is in my system path. If I check gems server, it shows that I have installed sqlite3-ruby 1.3.2 gem. Not sure what the problem could be? I am using ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10]. Macports claims this is the latest (although ive seen 1.9.1) One more thing-- in irb, I tried to check which version of sqlite3 my sqlite3-ruby is bound to, but I can only get this far: ":irb(main):001:0 require 'rubygems' = true irb(main):002:0 require 'sqlite3' /Users/dpetrovi/.gem/ruby/1.8/gems/sqlite3-ruby-1.3.2/lib/sqlite3/sqlite3_native.bundle: [BUG] Segmentation fault ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10] Abort trap" Any suggestions? Im hoping I overlooked something obvious. Thanks

    Read the article

  • How can I load a file into a DataBag from within a Yahoo PigLatin UDF?

    - by Cervo
    I have a Pig program where I am trying to compute the minimum center between two bags. In order for it to work, I found I need to COGROUP the bags into a single dataset. The entire operation takes a long time. I want to either open one of the bags from disk within the UDF, or to be able to pass another relation into the UDF without needing to COGROUP...... Code: # **** Load files for iteration **** register myudfs.jar; wordcounts = LOAD 'input/wordcounts.txt' USING PigStorage('\t') AS (PatentNumber:chararray, word:chararray, frequency:double); centerassignments = load 'input/centerassignments/part-*' USING PigStorage('\t') AS (PatentNumber: chararray, oldCenter: chararray, newCenter: chararray); kcenters = LOAD 'input/kcenters/part-*' USING PigStorage('\t') AS (CenterID:chararray, word:chararray, frequency:double); kcentersa1 = CROSS centerassignments, kcenters; kcentersa = FOREACH kcentersa1 GENERATE centerassignments::PatentNumber as PatentNumber, kcenters::CenterID as CenterID, kcenters::word as word, kcenters::frequency as frequency; #***** Assign to nearest k-mean ******* assignpre1 = COGROUP wordcounts by PatentNumber, kcentersa by PatentNumber; assignwork2 = FOREACH assignpre1 GENERATE group as PatentNumber, myudfs.kmeans(wordcounts, kcentersa) as CenterID; basically my issue is that for each patent I need to pass the sub relations (wordcounts, kcenters). In order to do this, I do a cross and then a COGROUP by PatentNumber in order to get the set PatentNumber, {wordcounts}, {kcenters}. If I could figure a way to pass a relation or open up the centers from within the UDF, then I could just GROUP wordcounts by PatentNumber and run myudfs.kmeans(wordcount) which is hopefully much faster without the CROSS/COGROUP. This is an expensive operation. Currently this takes about 20 minutes and appears to tack the CPU/RAM. I was thinking it might be more efficient without the CROSS. I'm not sure it will be faster, so I'd like to experiment. Anyway it looks like calling the Loading functions from within Pig needs a PigContext object which I don't get from an evalfunc. And to use the hadoop file system, I need some initial objects as well, which I don't see how to get. So my question is how can I open a file from the hadoop file system from within a PIG UDF? I also run the UDF via main for debugging. So I need to load from the normal filesystem when in debug mode. Another better idea would be if there was a way to pass a relation into a UDF without needing to CROSS/COGROUP. This would be ideal, particularly if the relation resides in memory.. ie being able to do myudfs.kmeans(wordcounts, kcenters) without needing the CROSS/COGROUP with kcenters... But the basic idea is to trade IO for RAM/CPU cycles. Anyway any help will be much appreciated, the PIG UDFs aren't super well documented beyond the most simple ones, even in the UDF manual.

    Read the article

  • What is a good platform for building a game framework targetting both web and native languages?

    - by fuzzyTew
    I would like to develop (or find, if one is already in development) a framework with support for accelerated graphics and sound built on a system flexible enough to compile to the following: native ppc/x86/x86_64/arm binaries or a language which compiles to them javascript actionscript bytecode or a language which compiles to it (actionscript 3, haxe) optionally java I imagine, for example, creating an API where I can open windows and make OpenGL-like calls and the framework maps this in a relatively efficient manner to either WebGL with a canvas object, 3d graphics in Flash, OpenGL ES 2 with EGL, or desktop OpenGL in an X11, Windows, or Cocoa window. I have so far looked into these avenues: Building the game library in haXe Pros: Targets exist for php, javascript, actionscript bytecode, c++ High level, object oriented language Cons: No support for finally{} blocks or destructors, making resource cleanup difficult C++ target does not allow room for producing highly optimized libraries -- the foreign function interface requires all primitive types be boxed in a wrapper object, as if writing bindings for a scripting language; these feel unideal for real-time graphics and audio, especially exporting low-level functions. Doesn't seem quite yet mature Using the C preprocessor to create a translator, writing programs entirely with macros Pros: CPP is widespread and simple to use Cons: This is an arduous task and probably the wrong tool for the job CPP implementations differ widely in support for features (e.g. xcode cpp has no variadic macros despite claiming C99 compliance) There is little-to-no room for optimization in this route Using llvm's support for multiple backends to target c/c++ to web languages Pros: Can code in c/c++ LLVM is a very mature highly optimizing compiler performing e.g. global inlining Targets exist for actionscript (alchemy) and javascript (emscripten) Cons: Actionscript target is closed source, unmaintained, and buggy. Javascript targets do not use features of HTML5 for appropriate optimization (e.g. linear memory with typed arrays) and are immature An LLVM target must convert from low-level bytecode, so high-level constructs are lost and bloated unreadable code is created from translating individual instructions, which may be more difficult for an unprepared JIT to optimize. "jump" instructions cause problems for languages with no "goto" statements. Using libclang to write a translator from C/C++ to web languages Pros: A beautiful parsing library providing easy access to the code structure Can code in C/C++ Has sponsored developer effort from Apple Cons: Incomplete; current feature set targets IDEs. Basic operators are unexposed and must be manually parsed from the returned AST element to be identified. Translating code prior to compilation may forgo optimizations assumed in c/c++ such as inlining. Creating new code generators for clang to translate into web languages Pros: Can code in C/C++ as libclang Cons: There is no API; code structure is unstable A much larger job than using libclang; the innards of clang are complex Building the game library in Common Lisp Pros: Flexible, ancient, well-developed language Extensive introspection should ease writing translators Translators exist for at least javascript Cons: Unfamiliar language No standardized library functions, widely varying implementations Which of these avenues should I pursue? Do you know of any others, or any systems that might be useful? Does a general project like this exist somewhere already? Thank you for any input.

    Read the article

  • Cannot run public class in one .java from another

    - by DIOS
    I have created a basic program that takes whatever is input into two textfields and exports them to a file. I would now like to encrypt that file, and alredy have the encryptor. The problem is that I cannot call it. Here is my code for the encryptor: import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.*; import javax.crypto.Cipher; import javax.crypto.CipherInputStream; import javax.crypto.CipherOutputStream; import javax.crypto.spec.SecretKeySpec; public class FileEncryptor { private String algo; private File file; public FileEncryptor(String algo,String path) { this.algo=algo; //setting algo this.file=new File(path); //settong file } public void encrypt() throws Exception{ //opening streams FileInputStream fis =new FileInputStream(file); file=new File(file.getAbsolutePath()); FileOutputStream fos =new FileOutputStream(file); //generating key byte k[] = "HignDlPs".getBytes(); SecretKeySpec key = new SecretKeySpec(k,algo.split("/")[0]); //creating and initialising cipher and cipher streams Cipher encrypt = Cipher.getInstance(algo); encrypt.init(Cipher.ENCRYPT_MODE, key); CipherOutputStream cout=new CipherOutputStream(fos, encrypt); byte[] buf = new byte[1024]; int read; while((read=fis.read(buf))!=-1) //reading data cout.write(buf,0,read); //writing encrypted data //closing streams fis.close(); cout.flush(); cout.close(); } public static void main (String[] args)throws Exception { new FileEncryptor("DES/ECB/PKCS5Padding","C:\\Users\\*******\\Desktop\\newtext").encrypt();//encrypts the current file. } } Here is the section of my file creator that is failing to call this: FileWriter fWriter = null; BufferedWriter writer = null; try{ fWriter = new FileWriter("C:\\Users\\*******\\Desktop\\newtext"); writer = new BufferedWriter(fWriter); writer.write(Data); writer.close(); f.dispose(); FileEncryptor encr = new FileEncryptor(); //problem lies here. encr.encrypt //public void that does the encryption. new complete(); //different .java that is working fine.

    Read the article

  • WMS authentication plugin

    - by roul
    Hi, I'm trying to create a custom authentication plugin for WMS 2009 in C#. I managed to implement something that for some reason blocks all requests... [ComVisible(true)] [Guid("C0A0B38C-C4FE-43B5-BE9E-C100A83BBCEE")] public class AuthenticationPlugin : IWMSBasicPlugin, IWMSAuthenticationPlugin, IWMSAuthenticationContext private const string SubKey = "SOFTWARE\\Microsoft\\Windows Media\\Server\\RegisteredPlugins\\Authentication\\{C0A0B38C-C4FE-43B5-BE9E-C100A83BBCEE}"; [ComRegisterFunction] public static void RegisterFunction(Type t) { try { RegistryKey regHKLM = Registry.LocalMachine; regHKLM = regHKLM.CreateSubKey(SubKey); regHKLM.SetValue(null, "UC WMS Authentication plugin"); RegistryKey regHKCR = Registry.ClassesRoot; regHKCR = regHKCR.CreateSubKey("CLSID\\{C0A0B38C-C4FE-43B5-BE9E-C100A83BBCEE}\\Properties"); regHKCR.SetValue("Name", CustomC WMS Authentication plugin"); regHKCR.SetValue("Author", "Me"); regHKCR.SetValue("CopyRight", "Copyright 2009. All rights reserved"); regHKCR.SetValue("Description", "Enables custom WMS authentication"); } catch (Exception error) { Console.WriteLine(error.Message, "Inside RegisterFunction(). Cannot Register."); } } [ComUnregisterFunction] public static void UnRegisterFunction(Type t) { try { RegistryKey regHKLM = Registry.LocalMachine; regHKLM.DeleteSubKey(SubKey); RegistryKey regHKCR = Registry.ClassesRoot; regHKCR.DeleteSubKeyTree("CLSID\\{C0A0B38C-C4FE-43B5-BE9E-C100A83BBCEE}"); regHKCR.DeleteSubKeyTree("CSEventTest.CSEventPlugin"); } catch (Exception error) { Console.WriteLine(error.Message, "Cannot delete a subkey."); } } #region IWMSBasicPlugin Members public void InitializePlugin(IWMSContext serverContext, WMSNamedValues namedValues, IWMSClassObject classFactory) { } public void ShutdownPlugin() { } public void EnablePlugin(ref int flags, ref int heartbeatPeriod) { } public void DisablePlugin() { } public object GetCustomAdminInterface() { return null; } public void OnHeartbeat() { } #endregion #region IWMSAuthenticationPlugin Members public IWMSAuthenticationContext CreateAuthenticationContext() { return (IWMSAuthenticationContext)this; } public int GetFlags() { return Convert.ToInt32(WMS_AUTHENTICATION_FLAGS.WMS_AUTHENTICATION_ANONYMOUS, CultureInfo.InvariantCulture); } public string GetPackageName() { return "Custom WMS Authentication"; } public string GetProtocolName() { return "Basic"; } #endregion #region IWMSAuthenticationContext Members public void Authenticate(object responseBlob, IWMSContext userContext, IWMSContext presentationContext, IWMSCommandContext commandContext, IWMSAuthenticationCallback callBack, object context) { callBack.OnAuthenticateComplete(WMS_AUTHENTICATION_RESULT.WMS_AUTHENTICATION_SUCCESS, null, context); } public IWMSAuthenticationPlugin GetAuthenticationPlugin() { return (IWMSAuthenticationPlugin)this; } public string GetImpersonationAccountName() { return String.Empty; } public int GetImpersonationToken() { return 0; } public string GetLogicalUserID() { return this.GetImpersonationAccountName(); } #endregion } Can anyone spot why this is happening? Also, is there any way I could have a look at the code for the standard Anonymous Authentication plugin already installed on the server? Is it in an assembly somewhere? Thanks.

    Read the article

  • Workflow for statistical analysis and report writing

    - by ws
    Does anyone have any wisdom on workflows for data analysis related to custom report writing? The use-case is basically this: Client commissions a report that uses data analysis, e.g. a population estimate and related maps for a water district. The analyst downloads some data, munges the data and saves the result (e.g. adding a column for population per unit, or subsetting the data based on district boundaries). The analyst analyzes the data created in (2), gets close to her goal, but sees that needs more data and so goes back to (1). Rinse repeat until the tables and graphics meet QA/QC and satisfy the client. Write report incorporating tables and graphics. Next year, the happy client comes back and wants an update. This should be as simple as updating the upstream data by a new download (e.g. get the building permits from the last year), and pressing a "RECALCULATE" button, unless specifications change. At the moment, I just start a directory and ad-hoc it the best I can. I would like a more systematic approach, so I am hoping someone has figured this out... I use a mix of spreadsheets, SQL, ARCGIS, R, and Unix tools. Thanks! PS: Below is a basic Makefile that checks for dependencies on various intermediate datasets (w/ ".RData" suffix) and scripts (".R" suffix). Make uses timestamps to check dependencies, so if you 'touch ss07por.csv', it will see that this file is newer than all the files / targets that depend on it, and execute the given scripts in order to update them accordingly. This is still a work in progress, including a step for putting into SQL database, and a step for a templating language like sweave. Note that Make relies on tabs in its syntax, so read the manual before cutting and pasting. Enjoy and give feedback! http://www.gnu.org/software/make/manual/html%5Fnode/index.html#Top R=/home/wsprague/R-2.9.2/bin/R persondata.RData : ImportData.R ../../DATA/ss07por.csv Functions.R $R --slave -f ImportData.R persondata.Munged.RData : MungeData.R persondata.RData Functions.R $R --slave -f MungeData.R report.txt: TabulateAndGraph.R persondata.Munged.RData Functions.R $R --slave -f TabulateAndGraph.R report.txt

    Read the article

  • Django Multi-Table Inheritance VS Specifying Explicit OneToOne Relationship in Models

    - by chefsmart
    Hope all this makes sense :) I'll clarify via comments if necessary. Also, I am experimenting using bold text in this question, and will edit it out if I (or you) find it distracting. With that out of the way... Using django.contrib.auth gives us User and Group, among other useful things that I can't do without (like basic messaging). In my app I have several different types of users. A user can be of only one type. That would easily be handled by groups, with a little extra care. However, these different users are related to each other in hierarchies / relationships. Let's take a look at these users: - Principals - "top level" users Administrators - each administrator reports to a Principal Coordinators - each coordinator reports to an Administrator Apart from these there are other user types that are not directly related, but may get related later on. For example, "Company" is another type of user, and can have various "Products", and products may be supervised by a "Coordinator". "Buyer" is another kind of user that may buy products. Now all these users have various other attributes, some of which are common to all types of users and some of which are distinct only to one user type. For example, all types of users have to have an address. On the other hand, only the Principal user belongs to a "BranchOffice". Another point, which was stated above, is that a User can only ever be of one type. The app also needs to keep track of who created and/or modified Principals, Administrators, Coordinators, Companies, Products etc. (So that's two more links to the User model.) In this scenario, is it a good idea to use Django's multi-table inheritance as follows: - from django.contrib.auth.models import User class Principal(User): # # # branchoffice = models.ForeignKey(BranchOffice) landline = models.CharField(blank=True, max_length=20) mobile = models.CharField(blank=True, max_length=20) created_by = models.ForeignKey(User, editable=False, blank=True, related_name="principalcreator") modified_by = models.ForeignKey(User, editable=False, blank=True, related_name="principalmodifier") # # # Or should I go about doing it like this: - class Principal(models.Model): # # # user = models.OneToOneField(User, blank=True) branchoffice = models.ForeignKey(BranchOffice) landline = models.CharField(blank=True, max_length=20) mobile = models.CharField(blank=True, max_length=20) created_by = models.ForeignKey(User, editable=False, blank=True, related_name="principalcreator") modified_by = models.ForeignKey(User, editable=False, blank=True, related_name="principalmodifier") # # # Please keep in mind that there are other user types that are related via foreign keys, for example: - class Administrator(models.Model): # # # principal = models.ForeignKey(Principal, help_text="The supervising principal for this Administrator") user = models.OneToOneField(User, blank=True) province = models.ForeignKey( Province) landline = models.CharField(blank=True, max_length=20) mobile = models.CharField(blank=True, max_length=20) created_by = models.ForeignKey(User, editable=False, blank=True, related_name="administratorcreator") modified_by = models.ForeignKey(User, editable=False, blank=True, related_name="administratormodifier") I am aware that Django does use a one-to-one relationship for multi-table inheritance behind the scenes. I am just not qualified enough to decide which is a more sound approach.

    Read the article

  • show/hide html table columns using css

    - by Art Peterson
    I want to display a basic html table with controls to toggle showing/hiding of additional columns: <table id="mytable"> <tr> <th>Column 1</th> <th class="col1">1a</th> <th class="col1">1b</th> <th>Column 2</th> <th class="col2">2a</th> <th class="col2">2b</th> </tr> <tr> <td>100</td> <td class="col1">40</td> <td class="col1">60</td> <td>200</td> <td class="col2">110</td> <td class="col2">90</td> </tr> </table> So Column 1 and Column 2 will be the only columns displayed by default - but when you click on the Column 1 I want 1a and 1b to toggle, and same with Column 2 with 2a and 2b. I may end up with more columns and lots of rows - so any javascript looping approaches have been too slow to work with when I tested. The only approach that seems to be fast enough is to set up some css like this: table.hide1 .col1 { display: none; } table.hide2 .col2 { display: none; } table.hide3 .col3 { display: none; } table.show1 .col1 { display: table-cell; } table.show2 .col2 { display: table-cell; } table.show3 .col3 { display: table-cell; } And then set up onClick function calls on the table header cells that will trigger a toggle - and determine which css class to set "mytable" to that will create the toggle effect that I'm looking for. Is there an easy way to set this up so that the code can work for n # of columns?

    Read the article

  • C# Reading and Writing a Char[] to and from a Byte[]

    - by Simon G
    Hi, I have a byte array of around 10,000 bytes which is basically a blob from delphi that contains char, string, double and arrays of various types. This need to be read in and updated via C#. I've created a very basic reader that gets the byte array from the db and converts the bytes to the relevant object type when accessing the property which works fine. My problem is when I try to write to a specific char[] item, it doesn't seem to update the byte array. I've created the following extensions for reading and writing: public static class CharExtension { public static byte ToByte( this char c ) { return Convert.ToByte( c ); } public static byte ToByte( this char c, int position, byte[] blob ) { byte b = c.ToByte(); blob[position] = b; return b; } } public static class CharArrayExtension { public static byte[] ToByteArray( this char[] c ) { byte[] b = new byte[c.Length]; for ( int i = 1; i < c.Length; i++ ) { b[i] = c[i].ToByte(); } return b; } public static byte[] ToByteArray( this char[] c, int positon, int length, byte[] blob ) { byte[] b = c.ToByteArray(); Array.Copy( b, 0, blob, positon, length ); return b; } } public static class ByteExtension { public static char ToChar( this byte[] b, int position ) { return Convert.ToChar( b[position] ); } } public static class ByteArrayExtension { public static char[] ToCharArray( this byte[] b, int position, int length ) { char[] c = new char[length]; for ( int i = 0; i < length; i++ ) { c[i] = b.ToChar( position ); position += 1; } return c; } } to read and write chars and char arrays my code looks like: Byte[] _Blob; // set from a db field public char ubin { get { return _tariffBlob.ToChar( 14 ); } set { value.ToByte( 14, _Blob ); } } public char[] usercaplas { get { return _tariffBlob.ToCharArray( 2035, 10 ); } set { value.ToByteArray( 2035, 10, _Blob ); } } So to write to the objects I can do: ubin = 'C'; // this will update the byte[] usercaplas = new char[10] { 'A', 'B', etc. }; // this will update the byte[] usercaplas[3] = 'C'; // this does not update the byte[] I know the reason is that the setter property is not being called but I want to know is there a way around this using code similar to what I already have? I know a possible solution is to use a private variable called _usercaplas that I set and update as needed however as the byte array is nearly 10,000 bytes in length the class is already long and I would like a simpler approach as to reduce the overall code length and complexity. Thank

    Read the article

  • How to combine designable components with dependency injection

    - by Wim Coenen
    When creating a designable .NET component, you are required to provide a default constructor. From the IComponent documentation: To be a component, a class must implement the IComponent interface and provide a basic constructor that requires no parameters or a single parameter of type IContainer. This makes it impossible to do dependency injection via constructor arguments. (Extra constructors could be provided, but the designer would ignore them.) Some alternatives we're considering: Service Locator Don't use dependency injection, instead use the service locator pattern to acquire dependencies. This seems to be what IComponent.Site.GetService is for. I guess we could create a reusable ISite implementation (ConfigurableServiceLocator?) which can be configured with the necessary dependencies. But how does this work in a designer context? Dependency Injection via properties Inject dependencies via properties. Provide default instances if they are necessary to show the component in a designer. Document which properties need to be injected. Inject dependencies with an Initialize method This is much like injection via properties but it keeps the list of dependencies that need to be injected in one place. This way the list of required dependencies is documented implicitly, and the compiler will assists you with errors when the list changes. Any idea what the best practice is here? How do you do it? edit: I have removed "(e.g. a WinForms UserControl)" since I intended the question to be about components in general. Components are all about inversion of control (see section 8.3.1 of the UMLv2 specification) so I don't think that "you shouldn't inject any services" is a good answer. edit 2: It took some playing with WPF and the MVVM pattern to finally "get" Mark's answer. I see now that visual controls are indeed a special case. As for using non-visual components on designer surfaces, I think the .NET component model is fundamentally incompatible with dependency injection. It appears to be designed around the service locator pattern instead. Maybe this will start to change with the infrastructure that was added in .NET 4.0 in the System.ComponentModel.Composition namespace.

    Read the article

< Previous Page | 440 441 442 443 444 445 446 447 448 449 450 451  | Next Page >