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  • How to Overcome or fix MIXED_DML_OPERATION error in Salesforce APEX without future method ?

    - by sathya
    How to Overcome or fix MIXED_DML_OPERATION error in Salesforce APEX without future method ?MIXED_DML_OPERATION :-one of the worst issues we have ever faced :)While trying to perform DML operation on a setup object and non-setup object in a single action you will face this error.Following are the solutions I tried and the final one worked out :-1. perform the 1st objects DML on normal apex method. Then Call the 2nd objects DML through a future method.    Drawback :- You cant get a response from the future method as its context is different and because its executing asynchronously and that its static.2. Tried the following option but it didnt work :-    1. perform the dml operation on the normal apex method.    2. tried calling the 2nd dml from trigger thinking that it would be in a different context. But it didnt work.    3. Some suggestions were given in some blogs that we could try System.runas()   Unfortunately that works only for test class.   4. Finally achieved it with response synchronously through the following solution :-    a. Created 2 apex:commandbuttons :-        1. <apex:commandButton value="Save and Send Activation Email" action="{!CreateContact}"  rerender="junkpanel" oncomplete="callSimulateUserSave()">            Note :- Oncomplete will not work if you dont have a rerender attribute. So just try refreshing a junk panel.        2. <apex:commandButton value="SimulateUserSave" id="SimulateUserSave" action="{!SaveUser}"  style="display:none;margin-left:5px;"/>        Have a junk panel as well just for rerendering  :-        <apex:outputPanel id="junkpanel"></apex:outputPanel>    b. Created this javascript function which is called from first button's oncomplete and clicks the second button :-                function callSimulateUserSave()                {                    // Specify the id of the button that needs to be clicked. This id is based on the Apex Component Hierarchy.                    // You will not get this value if you dont have the id attribute in the button which needs to be clicked from javascript                    // If you have any doubt in getting this value. Just hover over the button using Chrome developer tools to get the id.                    // But it will show like theForm:SimulateUserSave but you need to replace the colon with a dot here.                    // Note :- I have given display:none in the style of the second button to make sure that, it is not visible for the user.                    var mybtn=document.getElementById('{!$Component.theForm.SimulateUserSave}');                                    mybtn.click();                }    c. Apex Methods CreateContact and SaveUser are the pagereference methods which contains the code to create contact and user respectively.       After inserting the user inside the second apex method you can just set some public Properties in the page,        for ex:- created userid to get the user details and display in the page to show the acknowledgement to the users that the User is created.

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  • there is no attribute "border"

    - by ptahiliani
    Sometimes we got this error message when we try to validate our asp.net website on w3c. To solve this error you need to write the PreRender event. Here is the complete event: Protected Sub Page_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreRender         imgBtnGo.Style.Remove(HtmlTextWriterStyle.BorderWidth)         imgBtnGo.Attributes.Remove("border") End Sub

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  • Problem in installing player/gazebo

    - by usama yaseen
    I am using ubuntu 10.04 (64-bit), i have sucessfully installed all the dependancies of player and gazebo, then i installed player 3.01 and then gazebo 0.9,Now the when i run this gazebo worlds/pioneer2dx.world I get a gazebo interface, everything is ok uptill now, but when i run this cd gazebo/player player gazebo.cfg player: error while loading shared libraries: libplayerdrivers.so.3.0: cannot open shared object file: No such file or directory I guess the problem is somewhere in the environmental variables, can anyone please help me to solve this?

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  • Unit-testing code that relies on untestable 3rd party code

    - by DudeOnRock
    Sometimes, especially when working with third party code, I write unit-test specific code in my production code. This happens when third party code uses singletons, relies on constants, accesses the file-system/a resource I don't want to access in a test situation, or overuses inheritance. The form my unit-test specific code takes is usually the following: if (accessing or importing a certain resource fails) I assume this is a test case and load a mock object Is this poor form, and if it is, what is normally done when writing tests for code that uses untestable third party code?

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  • Image first loaded, then it isn't? (XNA)

    - by M0rgenstern
    I am very confused at the Moment. I have the following Class: (Just a part of the class): public class GUIWindow { #region Static Fields //The standard image for windows. public static IngameImage StandardBackgroundImage; #endregion } IngameImage is just one of my own classes, but actually it contains a Texture2D (and some other things). In another class I load a list of GUIButtons by deserializing a XML file. public static GUI Initializazion(string pXMLPath, ContentManager pConMan) { GUI myGUI = pConMan.Load<GUI>(pXMLPath); GUIWindow.StandardBackgroundImage = new IngameImage(pConMan.Load<Texture2D>(myGUI.WindowStandardBackgroundImagePath), Vector2.Zero, 1024, 600, 1, 0, Color.White, 1.0f, true, false, false); System.Console.WriteLine("Image loaded? " + (GUIWindow.StandardBackgroundImage.ImageStrip != null)); myGUI.Windows = pConMan.Load<List<GUIWindow>>(myGUI.GUIFormatXMLPath); System.Console.WriteLine("Windows loaded"); return myGUI; } Here this line: System.Console.WriteLine("Image loaded? " + (GUIWindow.StandardBackgroundImage.ImageStrip != null)); Prints "true". To load the GUIWindows I need an "empty" constructor, which looks like that: public GUIWindow() { Name = ""; Buttons = new List<Button>(); ImagePath = ""; System.Console.WriteLine("Image loaded? (In win) " + (GUIWindow.StandardBackgroundImage.ImageStrip != null)); //Image = new IngameImage(StandardBackgroundImage); //System.Console.WriteLine( //Image.IsActive = false; SelectedButton = null; IsActive = false; } As you can see, I commented lines out in the constructor. Because: Otherwise this would crash. Here the line System.Console.WriteLine("Image loaded? (In win) " + (GUIWindow.StandardBackgroundImage.ImageStrip != null)); Doesn't print anything, it just crashes with the following errormessage: Building content threw NullReferenceException: Object reference not set to an object instance. Why does this happen? Before the program wants to load the List, it prints "true". But in the constructor, so in the loading of the list it prints "false". Can anybody please tell me why this happens and how to fix it?

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  • 2D camera perspective projection from 3D coordinates -- HOW?

    - by Jack
    I am developing a camera for a 2D game with a top-down view that has depth. It's almost a 3D camera. Basically, every object has a Z even though it is in 2D, and similarly to parallax layers their position, scale and rotation speed vary based on their Z. I guess this would be a perspective projection. But I am having trouble converting the objects' 3D coordinates into the 2D space of the screen so that everything has correct perspective and scale. I never learned matrices though I did dig the topic a bit today. I tried without using matrices thanks to this article but every attempt gave awkward results. I'm using ActionScript 3 and Flash 11+ (Starling), where the screen coordinates work like this: Left-handed coordinates system illustration I can explain further what I did if you want to help me sort out what's wrong, or you can directly tell me how you would do it properly. In case you prefer the former, read on. These are images showing the formulas I used: upload.wikimedia.org/math/1/c/8/1c89722619b756d05adb4ea38ee6f62b.png upload.wikimedia.org/math/d/4/0/d4069770c68cb8f1aa4b5cfc57e81bc3.png (Sorry new users can't post images, but both are from the wikipedia article linked above, section "Perspective projection". That's where you'll find what all variables mean, too) The long formula is greatly simplified because I believe a normal top-down 2D camera has no X/Y/Z rotation values (correct ?). Then it becomes d = a - c. Still, I can't get it to work. Maybe you could explain what numbers I should put in a(xyz), c(xyz), theta(xyz), and particularly, e(xyz) ? I don't quite get how e is different than c in my case. c.z is also an issue to me. If the Z of the camera's target object is 0, should the camera's Z be something like -600 ? ( = focal length of 600) Whatever I do, it's wrong. I only got it to work when I used arbitrary calculations that "looked" right, like most cameras with parallax layers seem to do, but that's fake! ;) If I want objects to travel between Z layers I might as well do it right. :) Thanks a lot for your help!

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  • What problems can arise from emulating concepts from another languages?

    - by Vandell
    I've read many times on the web that if your language doesn't support some concept, for example, object orientation, or maybe function calls, and it's considered a good practice in this other context, you should do it. The only problem I can see now is that other programmers may find your code too different than the usual, making it hard for them to program. What other problems do you think may arise from this?

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  • Caching items in Orchard

    - by Bertrand Le Roy
    Orchard has its own caching API that while built on top of ASP.NET's caching feature adds a couple of interesting twists. In addition to its usual work, the Orchard cache API must transparently separate the cache entries by tenant but beyond that, it does offer a more modern API. Here's for example how I'm using the API in the new version of my Favicon module: _cacheManager.Get( "Vandelay.Favicon.Url", ctx => { ctx.Monitor(_signals.When("Vandelay.Favicon.Changed")); var faviconSettings = ...; return faviconSettings.FaviconUrl; }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } There is no need for any code to test for the existence of the cache entry or to later fill that entry. Seriously, how many times have you written code like this: var faviconUrl = (string)cache["Vandelay.Favicon.Url"]; if (faviconUrl == null) { faviconUrl = ...; cache.Add("Vandelay.Favicon.Url", faviconUrl, ...); } Orchard's cache API takes that control flow and internalizes it into the API so that you never have to write it again. Notice how even casting the object from the cache is no longer necessary as the type can be inferred from the return type of the Lambda. The Lambda itself is of course only hit when the cache entry is not found. In addition to fetching the object we're looking for, it also sets up the dependencies to monitor. You can monitor anything that implements IVolatileToken. Here, we are monitoring a specific signal ("Vandelay.Favicon.Changed") that can be triggered by other parts of the application like so: _signals.Trigger("Vandelay.Favicon.Changed"); In other words, you don't explicitly expire the cache entry. Instead, something happens that triggers the expiration. Other implementations of IVolatileToken include absolute expiration or monitoring of the files under a virtual path, but you can also come up with your own.

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  • NHibernate Session Load vs Get when using Table per Hierarchy. Always use ISession.Get&lt;T&gt; for TPH to work.

    - by Rohit Gupta
    Originally posted on: http://geekswithblogs.net/rgupta/archive/2014/06/01/nhibernate-session-load-vs-get-when-using-table-per-hierarchy.aspxNHibernate ISession has two methods on it : Load and Get. Load allows the entity to be loaded lazily, meaning the actual call to the database is made only when properties on the entity being loaded is first accessed. Additionally, if the entity has already been loaded into NHibernate Cache, then the entity is loaded directly from the cache instead of querying the underlying database. ISession.Get<T> instead makes the call to the database, every time it is invoked. With this background, it is obvious that we would prefer ISession.Load<T> over ISession.Get<T> most of the times for performance reasons to avoid making the expensive call to the database. let us consider the impact of using ISession.Load<T> when we are using the Table per Hierarchy implementation of NHibernate. Thus we have base class/ table Animal, there is a derived class named Snake with the Discriminator column being Type which in this case is “Snake”. If we load This Snake entity using the Repository for Animal, we would have a entity loaded, as shown below: public T GetByKey(object key, bool lazy = false) { if (lazy) return CurrentSession.Load<T>(key); return CurrentSession.Get<T>(key); } var tRepo = new NHibernateReadWriteRepository<TPHAnimal>(); var animal = tRepo.GetByKey(new Guid("602DAB56-D1BD-4ECC-B4BB-1C14BF87F47B"), true); var snake = animal as Snake; snake is null As you can see that the animal entity retrieved from the database cannot be cast to Snake even though the entity is actually a snake. The reason being ISession.Load prevents the entity to be cast to Snake and will throw the following exception: System.InvalidCastException :  Message=Unable to cast object of type 'TPHAnimalProxy' to type 'NHibernateChecker.Model.Snake'. Thus we can see that if we lazy load the entity using ISession.Load<TPHAnimal> then we get a TPHAnimalProxy and not a snake. =============================================================== However if do not lazy load the same cast works perfectly fine, this is since we are loading the entity from database and the entity being loaded is not a proxy. Thus the following code does not throw any exceptions, infact the snake variable is not null: var tRepo = new NHibernateReadWriteRepository<TPHAnimal>(); var animal = tRepo.GetByKey(new Guid("602DAB56-D1BD-4ECC-B4BB-1C14BF87F47B"), false); var snake = animal as Snake; if (snake == null) { var snake22 = (Snake) animal; }

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  • Strategy to prevent players from seeing through walls in an online FPS?

    - by geneotech
    Why do we still moan on wallhackers in multiplayer first-person shooters ? Isn't it possible to perform occlusion culling for all players server-side ? For example, send player xyz information to client only when the player is visible in client's frustum and not occluded by any object ? Even if the collision-geometry is very simplified, most of the time cheater won't receive tactical information. Why not do this ?

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  • Recommended online training sites on software development

    - by liortal
    I am looking for an online training site that provides courses on software development topics. Subjects that are needed for my work are .NET, general object oriented principles, design patterns, unit testing, continuous integration but not limited to these in particular. I have tried to use Pluralsight which was nice, however i am not sure the style of videos only is sufficient (for my at least). Are there any other training companies that provide online courses in other formats that you found useful (regarding .NET but not limited only to it). Thanks

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  • Unable to run curl on on Ubuntu11.10

    - by ryy
    I ran : sudo apt-get install curl libcurl3 libcurl3-dev php5-curl Put: extension=php_curl.so in both /etc/php5/cli/php.ini and /etc/php5/apache2/php.ini But running php from the command line gives me the following error: PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib/php5/20090626+lfs/php_curl.so' - /usr/lib/php5/20090626+lfs/php_curl.so: cannot open shared object file: No such file or directory in Unknown on line 0 Running the install commands again tells me that everything is already the newest version. Running: locate php_curl.so Returns nothing.

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  • Combining Shared Secret and Certificates

    - by Michael Stephenson
    As discussed in the introduction article this walkthrough will explain how you can implement WCF security with the Windows Azure Service Bus to ensure that you can protect your endpoint in the cloud with a shared secret but also combine this with certificates so that you can identify the sender of the message.   Prerequisites As in the previous article before going into the walk through I want to explain a few assumptions about the scenario we are implementing but to keep the article shorter I am not going to walk through all of the steps in how to setup some of this. In the solution we have a simple console application which will represent the client application. There is also the services WCF application which contains the WCF service we will expose via the Windows Azure Service Bus. The WCF Service application in this example was hosted in IIS 7 on Windows 2008 R2 with AppFabric Server installed and configured to auto-start the WCF listening services. I am not going to go through significant detail around the IIS setup because it should not matter in relation to this article however if you want to understand more about how to configure WCF and IIS for such a scenario please refer to the following paper which goes into a lot of detail about how to configure this. The link is: http://tinyurl.com/8s5nwrz   Setting up the Certificates To keep the post and sample simple I am going to use the local computer store for all certificates but this bit is really just the same as setting up certificates for an example where you are using WCF without using Windows Azure Service Bus. In the sample I have included two batch files which you can use to create the sample certificates or remove them. Basically you will end up with: A certificate called PocServerCert in the personal store for the local computer which will be used by the WCF Service component A certificate called PocClientCert in the personal store for the local computer which will be used by the client application A root certificate in the Root store called PocRootCA with its associated revocation list which is the root from which the client and server certificates were created   For the sample Im just using development certificates like you would normally, and you can see exactly how these are configured and placed in the stores from the batch files in the solution using makecert and certmgr.   The Service Component To begin with let's look at the service component and how it can be configured to listen to the service bus using a shared secret but to also accept a username token from the client. In the sample the service component is called Acme.Azure.ServiceBus.Poc.Cert.Services. It has a single service which is the Visual Studio template for a WCF service when you add a new WCF Service Application so we have a service called Service1 with its Echo method. Nothing special so far!.... The next step is to look at the web.config file to see how we have configured the WCF service. In the services section of the WCF configuration you can see I have created my service and I have created a local endpoint which I simply used to do a little bit of diagnostics and to check it was working, but more importantly there is the Windows Azure endpoint which is using the ws2007HttpRelayBinding (note that this should also work just the same if your using netTcpRelayBinding). The key points to note on the above picture are the service behavior called MyServiceBehaviour and the service bus endpoints behavior called MyEndpointBehaviour. We will go into these in more detail later.   The Relay Binding The relay binding for the service has been configured to use the TransportWithMessageCredential security mode. This is the important bit where the transport security really relates to the interaction between the service and listening to the Azure Service Bus and the message credential is where we will use our certificate like we have specified in the message/clientCrentialType attribute. Note also that we have left the relayClientAuthenticationType set to RelayAccessToken. This means that authentication will be made against ACS for accessing the service bus and messages will not be accepted from any sender who has not been authenticated by ACS.   The Endpoint Behaviour In the below picture you can see the endpoint behavior which is configured to use the shared secret client credential for accessing the service bus and also for diagnostic purposes I have included the service registry element.     Hopefully if you are familiar with using Windows Azure Service Bus relay feature the above is very familiar to you and this is a very common setup for this section. There is nothing specific to the username token implementation here. The Service Behaviour Now we come to the bit with most of the certificate stuff in it. When you configure the service behavior I have included the serviceCredentials element and then setup to use the clientCertificate check and also specifying the serviceCertificate with information on how to find the servers certificate in the store.     I have also added a serviceAuthorization section where I will implement my own authorization component to perform additional security checks after the service has validated that the message was signed with a good certificate. I also have the same serviceSecurityAudit configuration to log access to my service. My Authorization Manager The below picture shows you implementation of my authorization manager. WCF will eventually hand off the message to my authorization component before it calls the service code. This is where I can perform some logic to check if the identity is allowed to access resources. In this case I am simple rejecting messages from anyone except the PocClientCertificate.     The Client Now let's take a look at the client side of this solution and how we can configure the client to authenticate against ACS but also send a certificate over to the service component so it can implement additional security checks on-premise. I have a console application and in the program class I want to use the proxy generated with Add Service Reference to send a message via the Azure Service Bus. You can see in my WCF client configuration below I have setup my details for the azure service bus url and am using the ws2007HttpRelayBinding.   Next is my configuration for the relay binding. You can see below I have configured security to use TransportWithMessageCredential so we will flow the token from a certificate with the message and also the RelayAccessToken relayClientAuthenticationType which means the component will validate against ACS before being allowed to access the relay endpoint to send a message.     After the binding we need to configure the endpoint behavior like in the below picture. This contains the normal transportClientEndpointBehaviour to setup the ACS shared secret configuration but we have also configured the clientCertificate to look for the PocClientCert.     Finally below we have the code of the client in the console application which will call the service bus. You can see that we have created our proxy and then made a normal call to a WCF in exactly the normal way but the configuration will jump in and ensure that a token is passed representing the client certificate.     Conclusion As you can see from the above walkthrough it is not too difficult to configure a service to use both a shared secret and certificate based token at the same time. This gives you the power and protection offered by the access control service in the cloud but also the ability to flow additional tokens to the on-premise component for additional security features to be implemented. Sample The sample used in this post is available at the following location: https://s3.amazonaws.com/CSCBlogSamples/Acme.Azure.ServiceBus.Poc.Cert.zip

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  • How do I install libtiff.so.3?

    - by Osama Ahmaro
    I installed Maya 2011 on Ubuntu 10.04 many times and it was always working, Recently i upgraded my Ubuntu from 10.04 to 11.04, and when i tried to install Maya 2011 on it i wasn’t able to get it working. After installing Maya 2011 on Ubuntu 11.04 i try to run Maya from the terminal and this is what i get : error while loading shared libraries: libtiff.so.3: cannot open shared object file: No such file or directory. Please help. Note : Maya is a 3d software.

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  • Many sources of movement in an entity system

    - by Sticky
    I'm fairly new to the idea of entity systems, having read a bunch of stuff (most usefully, this great blog and this answer). Though I'm having a little trouble understanding how something as simple as being able to manipualate the position of an object by an undefined number of sources. That is, I have my entity, which has a position component. I then have some event in the game which tells this entity to move a given distance, in a given time. These events can happen at any time, and will have different values for position and time. The result is that they'd be compounded together. In a traditional OO solution, I'd have some sort of MoveBy class, that contains the distance/time, and an array of those inside my game object class. Each frame, I'd iterate through all the MoveBy, and apply it to the position. If a MoveBy has reached its finish time, remove it from the array. With the entity system, I'm a little confused as how I should replicate this sort of behavior. If there were just one of these at a time, instead of being able to compound them together, it'd be fairly straightforward (I believe) and look something like this: PositionComponent containing x, y MoveByComponent containing x, y, time Entity which has both a PositionComponent and a MoveByComponent MoveBySystem that looks for an entity with both these components, and adds the value of MoveByComponent to the PositionComponent. When the time is reached, it removes the component from that entity. I'm a bit confused as to how I'd do the same thing with many move by's. My initial thoughts are that I would have: PositionComponent, MoveByComponent the same as above MoveByCollectionComponent which contains an array of MoveByComponents MoveByCollectionSystem that looks for an entity with a PositionComponent and a MoveByCollectionComponent, iterating through the MoveByComponents inside it, applying/removing as necessary. I guess this is a more general problem, of having many of the same component, and wanting a corresponding system to act on each one. My entities contain their components inside a hash of component type - component, so strictly have only 1 component of a particular type per entity. Is this the right way to be looking at this? Should an entity only ever have one component of a given type at all times?

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  • Rhythmbox is not launching

    - by Somogyi László
    I'm using Rhythmbox 2.99 in Ubuntu 13.10, and when I first launch the application it searches for music and works like a charm, but if I try to launch it later again nothing happens. When I run it in terminal I get this: $ rhythmbox (rhythmbox:8860): GLib-GObject-CRITICAL **: Custom constructor for class SoupServer returned NULL (which is invalid). Unable to remove object from construction_objects list, so memory was probably just leaked. Please use GInitable instead. Segmentation fault Any ideas how to make it work again?

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  • Should I close database connections after use in PHP?

    - by Sprottenwels
    I wonder if I should close any unnecessary database connection inside of my PHP scripts. I am aware of the fact that database connections are closed implicitly when the block stops executing and 'manually' closing the connections could kinda bloat the codebase with unnecessary code. But shouldn't I do so in order to make by code as readable and as easy understandable as possible, while also preventing several possible issues during run time? Also, if I would do, would it be enough to unset() my database object?

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  • Open Dialog, created with quickly does not work

    - by Marian Lux
    I tried to open a dialog like David Planella describs here (and quickly help add): Open Custom Dialog Windows (PyGTK + Quickly) But this don't works for me. I always get the same Error-Message if I open the creadted Dialog: AttributeError: 'module' object has no attribute 'NewDialogNameDialog' (Note: My Dialog-Name is replaced with "NewDialogNameDialog" to be more general.) I tried to test a tutorial for the Ubuntu app showdown to learn how to use quickly and python. I can also add the whole source-code if you wish.

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  • 16 things that could be improved in Ubuntu 10.04

    <b>OMG Ubuntu:</b> "In this post I'm going to list 16 things that I think could be improved in Lucid. I'm going to try my best to address the issues in detail and offer solutions. Of course, all of this is also a matter of opinion too. The object of this post is to make you think about ways we could improve each one."

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  • Why Are the Search Algorithms Still So Stupid?

    Anyway, it was back in '96 that I first tried Google (except I think they called it something else back then). It was as if the clouds broke open and the sun shone through. The results were stunningly similar to the object of my query. Prior to Google, you had these directories, the biggest among them Yahoo!

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  • Why do old programming languages continue to be revised?

    - by SunAvatar
    This question is not, "Why do people still use old programming languages?" I understand that quite well. In fact the two programming languages I know best are C and Scheme, both of which date back to the 70s. Recently I was reading about the changes in C99 and C11 versus C89 (which seems to still be the most-used version of C in practice and the version I learned from K&R). Looking around, it seems like every programming language in heavy use gets a new specification at least once per decade or so. Even Fortran is still getting new revisions, despite the fact that most people using it are still using FORTRAN 77. Contrast this with the approach of, say, the typesetting system TeX. In 1989, with the release of TeX 3.0, Donald Knuth declared that TeX was feature-complete and future releases would contain only bug fixes. Even beyond this, he has stated that upon his death, "all remaining bugs will become features" and absolutely no further updates will be made. Others are free to fork TeX and have done so, but the resulting systems are renamed to indicate that they are different from the official TeX. This is not because Knuth thinks TeX is perfect, but because he understands the value of a stable, predictable system that will do the same thing in fifty years that it does now. Why do most programming language designers not follow the same principle? Of course, when a language is relatively new, it makes sense that it will go through a period of rapid change before settling down. And no one can really object to minor changes that don't do much more than codify existing pseudo-standards or correct unintended readings. But when a language still seems to need improvement after ten or twenty years, why not just fork it or start over, rather than try to change what is already in use? If some people really want to do object-oriented programming in Fortran, why not create "Objective Fortran" for that purpose, and leave Fortran itself alone? I suppose one could say that, regardless of future revisions, C89 is already a standard and nothing stops people from continuing to use it. This is sort of true, but connotations do have consequences. GCC will, in pedantic mode, warn about syntax that is either deprecated or has a subtly different meaning in C99, which means C89 programmers can't just totally ignore the new standard. So there must be some benefit in C99 that is sufficient to impose this overhead on everyone who uses the language. This is a real question, not an invitation to argue. Obviously I do have an opinion on this, but at the moment I'm just trying to understand why this isn't just how things are done already. I suppose the question is: What are the (real or perceived) advantages of updating a language standard, as opposed to creating a new language based on the old?

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  • About Inbound Links

    For the object of search optimization processes inbound links are considered as among the best way to generate and direct high quality traffic to your website. The existence of a good pedigree of back links is always a good way to increase web traffic and gain that extra length over the competition.

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  • Aspect-oriented Programming and Code Contracts in ASP.NET MVC

    There are some aspects to application programming, such as logging, tracing, profiling, authentication and authorization that cut across the business objects. These are difficult to deal with in an object-oriented paradigm without resorting to code-injection, code-duplication or interdependencies. In ASP.NET MVC, you can use attributes in the form of action filters to provide a neater way of implementing these cross-curring concerns.

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