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  • calling constructor of the class in the destructor of the same class

    - by dicaprio
    Experts !! I know this question is one of the lousy one , but still I dared to open my mind , hoping I would learn from all. I was trying some examples as part of my routine and did this horrible thing, I called the constructor of the class from destructor of the same class. I don't really know if this is ever required in real programming , I cant think of any real time scenarios where we really need to call functions/CTOR in our destructor. Usually , destructor is meant for cleaning up. If my understanding is correct, why the compiler doesn't complain ? Is this because it is valid for some good reasons ? If so what are they ? I tried on Sun Forte, g++ and VC++ compiler and none of them complain about it. using namespace std; class test{ public: test(){ cout<<"CTOR"<<endl; } ~test() {cout<<"DTOR"<<endl; test(); }};

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  • AJAX/JSONP Question. Access id denied using IE while requesting corss domain.

    - by Sisir
    Ok, Here we go. I have already searched the Stack for the answer i have found some useful info but i want to clear up some more things. I also search the net for the answer but no real help. I have worked with some api (yelp, ouside.in). In yelp i use to inject the script to head with the url request to the api with a callback funcion. I worked fine in all browsers. But while using outside.in api when i call the url the callback in not working. In yelp they have a url field can be used like that callback=callbackfuncion so the callback will automatically called. But in outside.in there is not such field available. Is there are any standard command for callback function which will work regardless of any server/api? I also tried a standard ajax request using jQuery $.ajax() function. It worked for my local pc for both IE and other browser but did not working in IE showing the error: access denied, other borwser seems ok. Firebug in my FF also don't notice any errors. Outside.in has an javascript example but it is too hard to me to understand github.com/outsidein/api-examples/tree/master/javascript/browser/ site i am working: http://citystir.com yelp: yelp.com outside.in: outside.in Techniqual info: i am using: wampserver in local, wordpress for hosting, Godaddy, apache for remote with linux. Codes: Using Jquery $.ajax url is like: "http://hyperlocal-api.outside.in/v1.1/states/Illinois/cities/chicago/stories?dev_key="+key+"&sig="+signeture+"&limit=3 function makeOutsideRequest(url){ $.ajax({ url: url, dataType: 'json', type: 'GET', success: function (data, status, xhr) { if (data == null) { alert("An error occurred connecting to " + url + ". Please ensure that the server is running and configured to allow cross-origin requests."); }else{ printHomeNews(data); } }, error: function (xhr, status, error) { alert("An error occurred - check the server log for a stack trace."); } }); } Thanks!

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  • ASP.NET or PHP: Is Memcached useful for storing user-state information?

    - by hamlin11
    This question may expose my ignorance as a web developer, but that wouldn't exactly be a bad thing for me now would it? I have the need to store user-state information. Examples of information that I need to store per user. (define user: unauthenticated visitor) User arrived to the site from google/bing/yahoo User utilized the search feature (true/false) List of previous visited product pages on current visit It is my understanding that I could store this in the view state, but that causes a problem with page load from the end-users' perspective because a significant amount of non-viewable information is being transferred to and from the end-users even though the server is the only side that needs the info. On a similar note, it is my understanding that the session state can be used to store such information, but does not this also result in the same information being transferred to the user and stored in their cookie? (Not quite as bad as viewstate, but it does not feel ideal). This leaves me with either a server-only-session storage system or a mem-caching solution. Is memcached the only good option here?

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  • I want to build a Google-friendly web app, where should I start?

    - by ronii
    I have only very basic experience with HTML/CSS and have quite a bit of experience with testing software and web apps from a consumer perspective. I'd love to launch a web application that plays nicely with Google services, similar to some of the apps you'd find on the Google Apps Marketplace, such as ManyMoon, time to note, Socialwok, etc. I'm a huge Google fan and would like to build something that's well integrated with other Google services. If you were a total beginner and wanted to build a complex app like one of examples above (project management, CRM, etc), where would you start? If you worked your ass off 18 hours a day, 24/7, how fast could you do it? I've dabbled into various languages and development frameworks, and read about which apps are using what languages but it's hard to figure out what would be most beneficial to jump into. Ruby on Rails, PHP, Google Web Toolkit, AppEngine. The list goes on and on. I want to be able to build and launch my own scalable web app. Thanks.

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  • jQuery plugin Private functions inside Vs. Outside the each loop

    - by Pablo
    What is the difference between including private functions in a jQuery plugin in the examples below: Outside the loop: (function( $ ){ var defaults = {}; $.fn.cmFlex = function(opts) { this.each(function() { var $this = $(this); //Element specific options var o = $.extend({}, defaults, opts); //Code here }); function f1(){.... function f3(){.... function f2(){.... }; })( jQuery ); Inside the loop: (function( $ ){ var defaults = {}; $.fn.cmFlex = function(opts) { this.each(function() { var $this = $(this); //Element specific options var o = $.extend({}, defaults, opts); function f1(){.... function f3(){.... function f2(){.... }); }; })( jQuery ); The advantage of including the functions in the loop is that i will be able to access the $this variable as well as the Element specific options from f1() f2() f3(), are there any disadvantages to this?

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  • Is Mapping SIMPLE data to winform control really as hard as it seems?

    - by HotOil
    Hi: I'm making a leap from MFC to WinForms. It has all gone smoothly so far; The windows/gui parts of winforms app development are making good sense to me. But. Now all I want to do is display simple data types in the controls on the form, and retrieve them from the controls when the user clicks. This is a very simple operation in MFC.. (DataExchange) but seems to be much more complicated in .NET. Binding ? DataObject ? DataSet ? no.. I don't want a dataset or records or columns or any of that. I just want to map an or a bool to a checkbox or a radiobutton.. I have looked but have not found any good examples of doing this in C++. Is it really this hard? Really? What am I missing? Thanks-

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  • How to model and handle presentation DTO's to abstract from complicated domain model?

    - by arrages
    Hi I am developing an application that needs to work with a complex domain model using Hibernate. This application uses Spring MVC and using the domain objects in the presentation layer is very messy so I think I should use DTO's that go to and from my service layer so that these match what I need in my views. Now lets assume I have a CarLease entity whose properties are not simple java primitives but it's composed with other entities like Make, Model, etc public class CarLease { private Make make; Private Model model; . . . } most properties are in this fashion and they are selectable using drop down selects on the jsp view, each will post back an ID to the controller. Now considering some standard use cases: create, edit, display How would you go about modeling the presentation DTO's to be used as form backing objects and communication between presentation and service layers?? Would you create a different DTO for each case (create, edit, display), would you make DTO's for the complex attributes? if so where would you translate the ID to entity? how and where would you handle validation, DTO/Domain assembly, what would you return from service layer methods? (create, edit, get) As you can see, I now I will benefit by separating my view from the domain objects (very complex with lots of stuff I don't need.) but I am having a hard time finding any real world examples and best practices for this. I need some architecture guidance from top to bottom, please keep in mind I will use Spring MVC in case that may leverage on your anwser. thanks in advance.

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  • Wicket: Where to add components? Constructor? Or onBeforeRender?

    - by gmallett
    I'm a Wicket newb. This may just be my ignorance of the Wicket lifecycle so please enlighten me! My understanding is that Wicket WebPage objects are instantiated once and then serialized. This has led to a point of confusion for me, see below. Currently I have a template class which I intend to subclass. I followed the example in the Wicket docs demonstrating how to override the template's behavior in the subclass: protected void onBeforeRender() { add(new Label("title", getTitle())); super.onBeforeRender(); } protected String getTitle() { return "template"; } Subclass: protected String getTitle() { return "Home"; } This works very well. What's not clear to me are the "best practices" for this. It seems like onBeforeRender() is called on every request for the page, no? This seems like there would be substantially more processing done on a page if everything is in onBeforeRender(). I could easily follow the example of the other Wicket examples and add some components in the constructor that I do not want to override, but then I've divided by component logic into two places, something I'm hesitant to do. If I add a component that I intend to be in all subclasses, should I add it to the constructor or onBeforeRender()?

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  • Saving and restoring OpenGL model-view

    - by Tom
    I am a new-comer to OpenGL, and much of it remains mysterious to my feeble brain. I have been studying the NeHe demos as well as the Red Book. I am writing an Android application that displays the Earth in the center of the screen. The user can rotate the Earth about any axis (much like a very simple "Google Earth"). This code is working (I based it on the NeHe examples). Now I want to add a feature; the user should be able to save the current model orientation, then later return to that same orientation. For example, the user may save the Earth orientation such that the viewer is looking down at her hometown, and north-east is "up". How do I do this with OpenGL-ES? To capture and save the current orientation, my code could get the current model-view transformation matrix - I think I understand how to do that. But later on how do I apply that saved matrix to restore the view?

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  • suggestions on syntax to express mathematical formula concisely

    - by aaa
    hello. I am developing functional domain specific embedded language within C++ to translate formulas into working code as concisely and accurately as possible. I post prototype in the comment, it is about 2 hundred lines long. Right now my language looks something like this (well, actually is going to look like): // implies two nested loops j=0:N, i=0,j (range(i) < j < N)[T(i,j) = (T(i,j) - T(j,i))/e(i+j)]; // implies summation over above expression sum(range(i) < j < N))[(T(i,j) - T(j,i))/e(i+j)]; I am looking for possible syntax improvements/extensions or just different ideas about expressing mathematical formulas as clearly and precisely as possible (in any language, not just C++). Can you give me some syntax examples relating to my question which can be accomplished in your language of choice which consider useful. In particular, if you have some ideas about how to translate the above code segments, I would be happy to hear them. Thank you just to clarify and give actual formula, my short-term goal is to express the following expression concisely where values in <> are already computed as 4-dimensional array

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  • escape exactly what in javascript

    - by Emin
    Hi all, Being a newbie in javascript I came to a situation where I need more information on escaping characters in a string. Basically I know that in order to escape " I need to replace it with \" but what I don't know is for which characters I need to escape a particular string for. Is there a list of these "characters to escape"? or is it any character that is not a-zA-Z0-9 ? In my situation, I don't have control over the content that is being displayed on my page. Users enter some text and save it. I then use a webservice to extract them from the database, build a json array of objects, then iterate the array when I need to display them. In this case, I have - naturally - no idea of what the text the user has entered and therefore for what characters I need to escape. I also use jQuery for this specific project (just in case it has a function I am not aware of, to do what I need) Providing examples would be appreciated but I also want to learn the theory and logic behind it. Hope someone can be of any help.

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  • REST design: what verb and resource name to use for a filtering service

    - by kabaros
    I am developing a cleanup/filtering service that has a method that receives a list of objects serialized in xml, and apply some filtering rules to return a subset of those objects. In a REST-ful service, what verb shall I use for such a method? I thought that GET is a natural choice, but I have to put the serialized XML in the body of the request which works but feels incorrect. The other verbs don't seem to fit semantically. What is a good way to define that Service interface? Naming the resource /Cleanup or /Filter seems weird mainly because in the examples I see online, it is always a name rather than a verb being used for resource name. Am I right to feel that REST services are better suited for CRUD operations and you start bending the rules in situations like this service? If yes, am I then making a wrong architectural choice. I've pushed to develop this service in REST-ful style (as opposed to SOAP) for simplicity, but such awkward cases happen a lot and make me feel like I am missing something. Either choosing REST where it shouldn't be used or may be over-thinking some stuff that doesn't really matter? In that case, what really matters?

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  • Cocoa Drag and Drop, reading back the data. [Newbie]

    - by kodai
    Ok, I have a NSOutlineView set up, and I want it to capture PDF's if a pdf is dragged into the NSOutlineView. My first question, I have the following code: [outlineView registerForDraggedTypes:[NSArray arrayWithObjects:NSStringPboardType, NSFilenamesPboardType, nil]]; In all the apple Docs and examples I've seen I've also seen something like MySupportedType being an object registered for dragging. What does this mean? Do I change the code to be: [outlineView registerForDraggedTypes:[NSArray arrayWithObjects:@"pdf", NSStringPboardType, NSFilenamesPboardType, nil]]; Currently I have it set up to recognize drag and drop, and I can even make it spit out the URL of the dragged file once the drag is accepted, however, this leads me to my second question. I want to keep a copy of those PDF's app side. I suppose, and correct me if I'm wrong, that the best way to do this is to grab the data off the clipboard, save it in some persistant store, and that's that. (as apposed to using some sort of copy command and literally copying the file to the app director.) That being said, I'm not sure how to do that. I've the code: - (BOOL)outlineView:(NSOutlineView *)ov acceptDrop:(id <NSDraggingInfo>)info item:(id)item childIndex:(NSInteger)childIndex { NSPasteboard *pboard = [info draggingPasteboard]; NSURL *fileURL; if ( [[pboard types] containsObject:NSURLPboardType] ) { fileURL = [NSURL URLFromPasteboard:pboard]; // Perform operation using the file’s URL } NSData *data = [pboard dataForType:@"NSPasteboardTypePDF"]; But this never actually gets any data. Like I said before, it does get the URL, just not the data. Does anyone have any advise on how to get this going? Thanks so much!

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  • Implementations details of drag and drop of file path in cocoa.

    - by foo
    Hi, I'm trying to get a part of my window to react to drag and drop. In this case to copy the file path to the file being dropped on the view. I have looked over some documentation but I still have some problems to see exactly where I should implement my methods for drag and drop. I have seen some examples but almost all of them assumes that I want to drop an image on the view. I'm pretty new to cocoa and Xcode so, I have some problems with seeing the exact relation between interface builder and the generated code. I have created a subclass to NSView, called drop zone like this: #import <Cocoa/Cocoa.h> @interface dropZone : NSView { } @end I then use an NSRect to color it grey like this: #import "dropZone.h" @implementation dropZone - (void)drawRect:(NSRect)rect { NSRect bounds = [self bounds]; [[NSColor grayColor] set]; [NSBezierPath fillRect:bounds]; } @end I then drag this class to my window in interface builder. But I will need to implement the registerForDraggingTypes method, but where? I have also seen a convenience method in the Apple docs for file paths like this: dragFile:fromRect:slideBack:event: that might work.

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  • Interpreting item click in ListView

    - by Matt Huggins
    I'm working on my first Android project, and I created a menu via the XML method. My activity is pretty basic, in that it loads the main layout (containing a ListView with my String array of options). Here's the code inside my Activity: public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // allow stuff to happen when a list item is clicked ListView ls = (ListView)findViewById(R.id.menu); ls.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // @todo } }); } Within the onItemClick callback handler, I'd like to check which item was clicked, and load a new menu based upon that. Question 1: How do I go about figuring out which item was clicked? I can't find any straightforward examples on retrieving/testing the id value of the clicked item. Question 2: Once I have the id value, I assume I can just call the setContentView method again to change to another layout containing my new menu. Is that correct?

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  • How do I reference an instance of a class using its tag?

    - by Matt Winters
    I have several instances of a UIControl class Foo being instantiated, one instance corresponding to each cell in a UITableView. The Class has: BOOL selected; UIImageView *imageView; UIImage *imageOne; UIImage *imageTwo; I've assigned each instance a tag: foo.tag = indexPath.row; I would now like to reference the UIImageView.image for a (or several) specific instance(s) by its tag to switch it to the other image. In my search I've seen things like classes being assigned tags using initWithTag (I assume they're assigning tags)... SomeClass *someClass = [[SomeClass alloc]initWithTag:1 ... [someArray addObject: [[SomeClass alloc]initWithTag:2 ... [someArray addObject: [[SomeClass alloc]initWithTag:3 ... ...but I haven't seen how they are later referenced by that tag. I have seen a reference to getChildByTag which had promise, but I can't find it in the documentation or examples (maybe not iphone). Does anyone know how reference the imageView.image within an instance using its tag? Thanks

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  • Is there a jQuery Equivalent of YUI 2 Custom Event Publish/Subscribe Event Model?

    - by Abe
    Hello! I learned how to develop in Javascript using the YUI 2 library and was wondering if there is a jQuery equivalent of Custom Events (http://developer.yahoo.com/yui/event/#customevent) Specifically, I want to be able to define custom events without having to attach the listeners initially. In YUI, I would create a page class and declare different custom events that can be subscribed to. Below is some example code to demonstrate what I want to do, but with jQuery function ListPage() { var me = this; this.initEvent = new YAHOO.util.CustomEvent("initEvent"); this.init = function() { // initialize events, DOM, etc this.initEvent.fire(me); } } In application Javascript, I would then like to subscribe to the initEvent. var page = new ListPage(); page.initEvent.subscribe( function (type, args) { // do stuff here } ); page.init(); Are there any tutorials/examples of something this in jQuery? I understand I can do something similar using bind() and trigger(), but the impression I get is I have to pass in the event handler when I call bind(). Is it possible in jQuery to create the custom event, but pass in the event handler later? I hope my question makes sense. thanks!

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  • What do you call a generalized (non-GUI-related) "Model-View-Controller" architecture?

    - by dcuccia
    I am currently refactoring code that coordinates multiple hardware components for data acquisition, and feeling a bit like I'm recreating the wheel. In particular, an MVC-like pattern seems to be emerging. Except, this has nothing to do with a GUI and I'm worried that I'm forcing this particular pattern where another might be more appropriate. Here's my scenario: Individual hardware "component" classes obey interface contracts for each hardware type. Previously, component instances were orchestrated by a single monolithic InstrumentController class, which relied heavily on configuration + branching logic for executing a specific acquisition sequence. After an iteration, I have a separate controller for each component, with these controllers all managed by a small InstrumentControllerBase (or its derivatives). The composite system will receive "input" either programmatically or via inter-hardware component triggering - in either case these interactions are routed to, and handled by, the appropriate controller. So, I have something that feels MVC-esque, but I don't know if that's because I'm forcing the point. With little direct MVC experience in application development, it's hard to know if I'm just trying to make my scenario fit MVC, where another pattern might be a good alternative or complimentary. My problem is, search results and wiki documentation of these family of patterns seems to immediately drop me into GUI-specific discussions. I understand "M means Model data and the V means View" - but do you call the superset pattern? Component-Commander-Controller? Whence can I exhume examples exemplary?

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  • DCI: How to implement Context with Dependency Injection?

    - by ciscoheat
    Most examples of a DCI Context are implemented as a Command pattern. When using Dependency Injection though, it's useful to have the dependencies injected in the constructor and send the parameters into the executing method. Compare the Command pattern class: public class SomeContext { private readonly SomeRole _someRole; private readonly IRepository<User> _userRepository; // Everything goes into the constructor for a true encapsuled command. public SomeContext(SomeRole someRole, IRepository<User> userRepository) { _someRole = someRole; _userRepository = userRepository; } public void Execute() { _someRole.DoStuff(_userRepository); } } With the Dependency injected class: public class SomeContext { private readonly IRepository<User> _userRepository; // Only what can be injected using the DI provider. public SomeContext(IRepository<User> userRepository) { _userRepository = userRepository; } // Parameters from the executing method public void Execute(SomeRole someRole) { someRole.DoStuff(_userRepository); } } The last one seems a bit nicer, but I've never seen it implemented like this so I'm curious if there are any things to consider.

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  • Tiny MCE (jquery plugin version) not showing toolbar in IE (works fine in other browsers)

    - by I am Wonder
    I had an implementation working well but for some reason IE decided it was tired of playing nice. I have an advanced implementation of TinyMCE (the jquery plugin version - see http://tinymce.moxiecode.com/examples/example_23.php for details). It still works great in all browsers but IE. In IE it shows the drop-down options for Format, Font family, and Font size, but only as text.. not as a drop down normally looks. All other buttons on the toolbar are missing. (I've tried IE8 and IE8 Compatibility Mode) I get a javascript error: Syntax error Line 36 Char 1. Unfortunately the javascript is being loaded dynamically so this doesn't help me. Here is my implementation code for the TinyMCE editor: $(function () { $('#InputStuffHere').tinymce({ // General options theme: "advanced", plugins: "safari,pagebreak,style,layer,table,save,advhr,advimage,advlink,inlinepopups,preview,media,searchreplace,contextmenu,paste,fullscreen,noneditable,visualchars,nonbreaking,template", // Theme options theme_advanced_buttons1: "bold,italic,underline,strikethrough,|,justifyleft,justifycenter,justifyright,justifyfull,formatselect,fontselect,fontsizeselect,|,hr,removeformat", theme_advanced_buttons2: "cut,copy,paste,pastetext,pasteword,|,search,replace,|,bullist,numlist,|,outdent,indent,blockquote,|,undo,redo,|,link,unlink,image,|,forecolor,backcolor,|,spellchecker", theme_advanced_buttons3 : "", theme_advanced_toolbar_location: "top", theme_advanced_toolbar_align: "left", theme_advanced_statusbar_location: "bottom", theme_advanced_resizing: true, // Drop lists for link/image/media/template dialogs template_external_list_url: "lists/template_list.js", external_link_list_url: "lists/link_list.js", external_image_list_url: "lists/image_list.js", media_external_list_url: "lists/media_list.js", //initialization callback init_instance_callback: "TinyMCEReady", add_form_submit_trigger : false }); }); So... anyone seen anything like this or have any ideas for me? Thank you so much everyone!

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  • .tpl files and website problem

    - by whitstone86
    Apologies if the title is in lowercase but it's describing an extension format. I've started using Dwoo as my template engine for PHP, and am not sure how to convert my PHP files into .tpl templates. My site is similar to, but not the same as, http://library.digiguide.com/lib/programme/Medium-319648/Drama/ with its design (except colour scheme and site name are different, plus it's in PHP - so copyright issues are avoided here, the design arguably could be seen as parody even though the content is different. The database is called tvguide, and it has these tables: Programmes House M.D. Medium Police Stop! American Dad! The tablenames of the above programmes are: housemdonair mediumonair policestopair americandad1 Episodes The tablenames for the above programmes' episode guides are: housemdepidata mediumepidata policestopepidata americandad1epidata All of them have the following rows: id (not an auto-increment, since I wish to dynamically generate a page from this) episodename seriesnumber episodenumber episodesynopsis (the above four after id do exactly as stated) I have a pagination script that works, it displays 20 records per page as I want it to. This is called pmcPagination.php - but I won't post it in full since it would take up too much space. However, I'm trying to get it so that variables are filled in like this: (ok, so the examples below are ASP.NET, but if there's a PHP/MySQL equivalent I would gratefully appreciate this!!): http://library.digiguide.com/lib/episode/741168 http://library.digiguide.com/lib/episode/714829 with the episode detail and data. My site works, but it's fairly basic, and it's not online yet until my bugs are fixed. Mod_rewrite is enabled so my site reads as http://mytvguide.com/episode/123456 or http://mytvguide.com/programme/123456 http://mytvguide.com/WorldInAction/123456/Documentary/ I've tried looking on Google, but am not sure how to get this TV guide script to work at its best - but I think .tpl, and .php/MySQL is the way to go. Any advice anyone has on making this project into a fully workable, ready to use site would be much appreciated, I've spent months refining this project! P.S. Apologies for the length of this, hope it describes my project well.

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  • Displaying data from linked tables in netbeans JTable

    - by Darc
    I have been writing in java for a few months now and have just started using netbeans. I have spent all day today trying to work out how to connect to an SQL database and display data from 2 tables (ie display the data from from a select statement with an inner join) in a JTable. I have tried using JPQL with the following statment SELECT j, cust.name FROM Job j JOIN j.jobnumber cust where the job table has a field called customer that references id in the customer table. This throws the exception: Caused by: Exception [TOPLINK-8029] (Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions.EJBQLException Exception Description: Error compiling the query [SELECT j, cust.name FROM Job j JOIN j.jobnumber cust], line 1, column 11: invalid navigation expression [cust.name], cannot navigate expression [cust] of type [java.lang.Integer] inside a query. at oracle.toplink.essentials.exceptions.EJBQLException.invalidNavigation(EJBQLException.java:430) What am i doing wrong? Can anyone point me to some examples of how to make a linked table java application? I am still in the very early stages of development so a complete change is not out of the question if using a mysql database isnt the best way to go about things thanks

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  • When to use pointer to a class and when to just instantiate it as a variable

    - by Enders
    Im sort of confused by it. The best I could find was reading through the cplusplus.com tutorial and all they have to say about pointers to classes. "It is perfectly valid to create pointers that point to classes. We simply have to consider that once declared, a class becomes a valid type, so we can use the class name as the type for the pointer" Which tells me nothing about when to use them over the normal instantiation. I've seen the - operator many times, and looked at some codes but cant really decipher why they did it. Generic examples will be appreciated; but more specifically related to gui programming. Its where I encountered it first. QGridLayout *mainLayout = new QGridLayout; mainLayout->addWidget(nameLabel, 0, 0); mainLayout->addWidget(nameLine, 0, 1); mainLayout->addWidget(addressLabel, 1, 0, Qt::AlignTop); mainLayout->addWidget(addressText, 1, 1); Why not QGridLayout mainLayout mainLayout.addWidget ... (It doesnt compile if I change the sample code to that and try it but you get the point) Thanks in advance

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  • In Safari, using jQuery a Form Input Text Field does not receive focus after alert is displayed. Why

    - by Rob
    I have an ASPX web form. I use jQuery to simply my Javascript. I use a Javascript validation script to validate each of the form fields' values. If an error occurs, I popup an alert with an error message. Then I transfer focus to the underlying element. Here are examples I have tried. Using jQuery: var Form_FieldDef = function(name) { this.name = name; this.SetFocus = function() { $('#' + this.name)[0].focus(); } this.Validate = function() { var isvalid = true; if ( $.trim($('#' + this.name).val()) == '') { alert("Your entry is empty"); this.SetFocus(); isvalid = false; } return isvalid; } } This works on IE7, IE8, Opera, Chrome, and Firefox. It does not work on Safari 4 on PC. I don't have a Mac. So I changed the SetFocus method to this. this.SetFocus = function() { var fld = document.getElementById(this.name); if (fld != null) fld.focus(); } This works on IE7, IE8, Opera, Chrome, and Firefox. It does not work on Safari 4 on PC. I stepped through the code with VS 2008 debugger, and I'm calling the focus method on the underlying element.

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  • Changing direction of rotation Pygame

    - by czl
    How would you change the direction of a rotating image/rect in Pygame? Applying positive and negative degree values works but it seems to only be able to rotate one direction throughout my window. Is there a way to ensure a change in direction of rotation? Perhaps change up rotation of a spinning image every 5 seconds, or if able to change the direction of the spin when hitting a X or Y axis. I've added some code below. It seems like switching movement directions is easy with rect.move_ip as long as I specify a speed and have location clause, it does what I want. Unfortunately rotation is't like that. Here I'l adding angles to make sure it spins, but no matter what I try, I'm unable to negate the rotation. def rotate_image(self): #rotate image orig_rect = self.image.get_rect() rot_image = pygame.transform.rotate(self.image, self.angle) rot_rect = orig_rect.copy() rot_rect.center = rot_image.get_rect().center rot_image = rot_image.subsurface(rot_rect).copy() return rot_image def render(self): self.screen.fill(self.bg_color) self.rect.move_ip(0,5) #Y axis movement at 5 px per frame self.angle += 5 #add 5 anglewhen the rect has not hit one of the window self.angle %= 360 if self.rect.left < 0 or self.rect.right > self.width: self.speed[0] = -self.speed[0] self.angle = -self.angle #tried to invert the angle self.angle -= 5 #trying to negate the angle rotation self.angle %= 360 self.screen.blit(self.rotate_image(),self.rect) pygame.display.flip() I would really like to know how to invert rotation of a image. You may provide your own examples.

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