Search Results

Search found 69357 results on 2775 pages for 'data oriented design'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 477/2775 | < Previous Page | 473 474 475 476 477 478 479 480 481 482 483 484  | Next Page >

  • What is the best approach to binding commands in a ViewModel to elements in the View?

    - by Micah
    Anyone who has tried to implement RoutedCommands in WPF using M-V-VM has undoubtedly run into issues. Commands (non-UI commands that is) should be implemented in the ViewModel. For instance if I needed to save a CustomerViewModel then I would implement that as a command directly on my CustomerViewModel. However if I wanted to pop up a window to show the users addresses I would implement a ShowCustomerAddress command directly in the view since this a UI specific function. How do I define the command bindings in the viewmodel, and use them in the view?

    Read the article

  • Extending Throwable in Java

    - by polygenelubricants
    Java lets you create an entirely new subtype of Throwable, e.g: public class FlyingPig extends Throwable { ... } Now, very rarely, I may do something like this: throw new FlyingPig("Oink!"); and of course elsewhere: try { ... } catch (FlyingPig porky) { ... } My questions are: Is this a bad idea? And if so, why? What could've been done to prevent this subtyping if it is a bad idea? Since it's not preventable (as far as I know), what catastrophies could result? If this isn't such a bad idea, why not? How can you make something useful out of the fact that you can extends Throwable?

    Read the article

  • Modifying my website to allow anonymous comments

    - by David
    I write the code for my own website as an educational/fun exercise. Right now part of the website is a blog (like every other site out there :-/) which supports the usual basic blog features, including commenting on posts. But I only have comments enabled for logged-in users; I want to alter the code to allow anonymous comments - that is, I want to allow people to post comments without first creating a user account on my site, although there will still be some sort of authentication involved to prevent spam. Question: what information should I save for anonymous comments? I'm thinking at least display name and email address (for displaying a Gravatar), and probably website URL because I eventually want to accept OpenID as well, but would anything else make sense? Other question: how should I modify the database to store this information? The schema I have for the comment table is currently comment_id smallint(5) // The unique comment ID post_id smallint(5) // The ID of the post the comment was made on user_id smallint(5) // The ID of the user account who made the comment comment_subject varchar(128) comment_date timestamp comment_text text Should I add additional fields for name, email address, etc. to the comment table? (seems like a bad idea) Create a new "anonymous users" table? (and if so, how to keep anonymous user ids from conflicting with regular user ids) Or create fake user accounts for anonymous users in my existing users table? Part of what's making this tricky is that if someone tries to post an anonymous comment using an email address (or OpenID) that's already associated with an account on my site, I'd like to catch that and prompt them to log in.

    Read the article

  • How can I find out if an data- attribute is set to an empty value?

    - by Stephan Wagner
    Is there a way to find out if an data- attribute is set to an empty value or if it is not set at all? See this fiddle example (Check the console when clicking on the elements): http://jsfiddle.net/StephanWagner/yy8qvwfp/ <div onclick="console.log($(this).attr('data-test'))">undefined</div> <div data-test="" onclick="console.log($(this).attr('data-test'))">empty</div> <!-- this one will also return an empty value --> <div data-test onclick="console.log($(this).attr('data-test'))">null</div> <div data-test="value" onclick="console.log($(this).attr('data-test'))">value</div> Im having the issue with the third example. I need to know if the attribute actually is set to an empty value or if it is not set at all. Is that actually possible? EDIT: The reason I'm asking is that I'm updating content with the attributes value, so data-test="" should update the content to an empty value, but data-test should do nothing at all

    Read the article

  • Is a "factory" method the right pattern?

    - by jdt141
    Hey all - So I'm working to improve an existing implementation. I have a number of polymorphic classes that are all composed into a higher level container class. The problem I'm dealing with at the moment is that the higher level container class, well, sucks. It looks something like this, which I really don't have a problem with (as the polymorphic classes in the container should be public). My real issue is the constructor... /* * class1 and class 2 derive from the same superclass */ class Container { public: boost::shared_ptr<ComposedClass1> class1; boost::shared_ptr<ComposedClass2> class2; private: ... } /* * Constructor - builds the objects that we need in this container. */ Container::Container(some params) { class1.reset(new ComposedClass1(...)); class2.reset(new ComposedClass2(...)); } What I really need is to make this container class more re-usable. By hard-coding up the member objects and instantiating them, it basically isn't and can only be used once. A factory is one way to build what I need (potentially by supplying a list of objects and their specific types to be created?) Other ways to get around this problem? Seems like someone should have solved it before... Thanks!

    Read the article

  • Should a developer be a designer?

    - by nepb
    I have been developing websites for quite some time and I am not so good in designing websites? My Boss is refering me to take some lessons on it. But I really want to stick to development rather than designing?

    Read the article

  • Can the Singleton be replaced by Factory?

    - by lostiniceland
    Hello Everyone There are already quite some posts about the Singleton-Pattern around, but I would like to start another one on this topic since I would like to know if the Factory-Pattern would be the right approach to remove this "anti-pattern". In the past I used the singleton quite a lot, also did my fellow collegues since it is so easy to use. For example, the Eclipse IDE or better its workbench-model makes heavy usage of singletons as well. It was due to some posts about E4 (the next big Eclipse version) that made me start to rethink the singleton. The bottom line was that due to this singletons the dependecies in Eclipse 3.x are tightly coupled. Lets assume I want to get rid of all singletons completely and instead use factories. My thoughts were as follows: hide complexity less coupling I have control over how many instances are created (just store the reference I a private field of the factory) mock the factory for testing (with Dependency Injection) when it is behind an interface In some cases the factories can make more than one singleton obsolete (depending on business logic/component composition) Does this make sense? If not, please give good reasons for why you think so. An alternative solution is also appreciated. Thanks Marc

    Read the article

  • How To Implement The Query Side Of CQS in DDD?

    - by Laz
    I have implemented the command side of DDD using the domain model and repositories, but how do I implement the query side? Do I create an entirely new domain model for the UI, and where is this kept in the project structure...in the domain layer, the UI layer, etc? Also, what do I use as my querying mechanism, do I create new repositories specifically for the UI domain objects, something other than repositories, or something else?

    Read the article

  • Is there a recommended way to use the Observer pattern in MVP using GWT?

    - by Tomislav Nakic-Alfirevic
    I am thinking about implementing a user interface according to the MVP pattern using GWT, but have doubts about how to proceed. These are (some of) my goals: - the presenter knows nothing about the UI technology (i.e. uses nothing from com.google.*) - the view knows nothing about the model or the presenter - the model knows nothing of the view or the presenter (...obviously) I would place an interface between the view and the presenter and use the Observer pattern to decouple the two: the view generates events and the presenter gets notified. What confuses me is that java.util.Observer and java.util.Observable are not supported in GWT. This suggests that what I'm doing is not the recommended way to do it, as far as GWT is concerned, which leads me to my questions: what is the recommended way to implement MVP using GWT, specifically with the above goals in mind? How would you do it?

    Read the article

  • SQLite.Net Issue With BeginTransaction

    - by cam
    I'm trying to use System.Data.Sqlite library, and I'm following the documentation about optimizing inserts so I copied this code directly out of the documentation: using (SQLiteTransaction mytransaction = myconnection.BeginTransaction()) { using (SQLiteCommand mycommand = new SQLiteCommand(myconnection)) { SQLiteParameter myparam = new SQLiteParameter(); int n; mycommand.CommandText = "INSERT INTO [MyTable] ([MyId]) VALUES(?)"; mycommand.Parameters.Add(myparam); for (n = 0; n < 100000; n ++) { myparam.Value = n + 1; mycommand.ExecuteNonQuery(); } } mytransaction.Commit(); } Now, I initialize I connection right before that by using SqlConnection myconnection = new SqlConnection("Data Source=blah"); I have a Database named blah, with the correct tables and values. The problem is when I run this code, it says "Operation is not valid due to the current state of the object" I've tried changing the code around several times, and it still points to BeginTransaction. What gives?

    Read the article

  • C++ classes with members referencing each other

    - by Saad Imran.
    I'm trying to write 2 classes with members that reference each other. I'm not sure if I'm doing something wrong or it's just not possible. Can anyone help me out here... Source.cpp #include "Headers.h" using namespace std; void main() { Network* network = new Network(); system("pause"); return; } Headers.h #ifndef Headers_h #define Headers_h #include <iostream> #include <vector> #include "Network.h" #include "Router.h" #endif Network.h #include "Headers.h" class Network { protected: vector<Router> Routers; }; Router.h #include "Headers.h" class Router { protected: Network* network; public: }; The errors I'm getting are: error C2143: syntax error : missing ';' before '<' error C2238: unexpected token(s) preceding ';' error C4430: missing type specifier - int assumed. I'm pretty sure I'm not missing any semicolons or stuff like that. The program works find if I take out one of the members. I tried finding similar questions and the solution was to use pointers, but that's what I'm doing and it does't seem to be working!

    Read the article

  • O(log n) algorithm to find the element having rank i in union of pre-sorted lists

    - by Eternal Learner
    Given two sorted lists, each containing n real numbers, is there a O(log?n) time algorithm to compute the element of rank i (where i coresponds to index in increasing order) in the union of the two lists, assuming the elements of the two lists are distinct? I can think of using a Merge procedure to merge the 2 lists and then find the A[i] element in constant time. But the Merge would take O(n) time. How do we solve it in O(log n) time?

    Read the article

  • Django admin interface upload failing on request data read error

    - by Jake
    Hi All, This is an updated version of an old question I asked. I've now done a lot more testing, plus the old question got hijacked. I'm getting a request data read error when trying to upload files to the Django admin interface. Files under about 150k work, but bigger files always fail and almost always at around 192k (that's 3 chunks) completed, sometimes at around 160k. The Exception I get is below. File "/usr/lib/python2.4/site-packages/django/http/multipartparser.py", line 405, in read return self._file.read(num_bytes) IOError: request data read error I've tried Chrome and Firefox on Windows and Firefox on Mac - Same results. I can upload to other sites so I don't think it's my connection. I'm running python 2.4, django 1.1, mod_wsgi, on CentOS (a media temple DV server) Locally it's fine (Django development server) Everything I've found on this issue says it's a mod_python issue and that changing to mod_wsgi will fix it, but I am running mod_wsgi. Can anyone help?

    Read the article

  • Database model for saving random boolean expressions

    - by zarko.susnjar
    I have expressions like this: (cat OR cats OR kitten OR kitty) AND (dog OR dogs) NOT (pigeon OR firefly) Anyone having idea how to make tables to save those? Before I got request for usage of brackets, I limited usage of operators to avoid ambiguous situations. So only ANDs and NOTs or only ORs and saved those in this manner: operators id | name 1 | AND 2 | OR 3 | NOT keywords id | keyword 1 | cat 2 | dog 3 | firefly expressions id | operator | keywordId 1 | 0 | 1 1 | 1 | 2 1 | 3 | 3 which was: cat AND dog NOT firefly But now, I'm really puzzled...

    Read the article

  • Include everything, Separate with "using"

    - by Dave
    I'm developing a C++ library. It got me thinking of the ways Java and C# handle including different components of the libraries. For example, Java uses "import" to allow use of classes from other packages, while C# simply uses "using" to import entire modules. My questions is, would it be a good idea to #include everything in the library in one massive include and then just use the using directive to import specific classes and modules? Or would this just be down right crazy? EDIT: Good responses so far, here are a few mitigating factors which I feel add to this idea: 1) Internal #includes are kept as normal (short and to the point) 2) The file which includes everything is optionally supplied with the library to those who wish to use it3) You could optionally make the big include file part of the pre-compiled header

    Read the article

  • Load data from CSV to mySQL database Java+hibernate+spring

    - by mona
    I am trying to load a CSV file in to mySQL database using Java+Hibernate+Spring. I am using the following query in the DAO to help me load in to the database: entityManager.createQuery("LOAD DATA INFILE :fileName INTO TABLE test").setParameter("fileName", "C:\\samples\\test\\abcd.csv").executeUpdate(); I got some idea to use this from http://dev.mysql.com/doc/refman/5.1/en/load-data.html and how to import a csv file into a mysql from an hibernate+spring application? But I am getting the error: java.lang.IllegalArgumentException: node to traverse cannot be null! Please help! Thanks

    Read the article

  • Caching pictures from Picasa

    - by Renat
    Hello all, I'm creating an offline-capable IPhone app for showing pictures on picasa. It was pretty simple to use JQTouch and Google Data API (via JSONP), so I was able to show the albums and thumbnails in 3 hours, however I want that data to be cached, and for that I'm going to use the HTML 5 Application Cache (via xxx.manifest file). Now the question is what hosts shall I write there in order to cache pictures hosted on picasa. So far I've seen something like lh6.google.com or lh4.ggpht.com does anybody knows the full list of servers?

    Read the article

  • Ways to clean up java applications.

    - by Begui
    How do java people handle clean up of their apps when the program receives a kill signal? For instance, there is an application i connect to which wants any third party app ( my app) to send a "finish" command. What is the best say to send that "finish" command if one does a kill -9 on me.

    Read the article

  • Text -> Diagram Tool

    - by Jon
    I'm looking for an diagram tool for producing diagrams from text. I only really need sequence and state type diagrams for now, but I'm curious as to what people would recommend? I need something which is standalone, not a web based tool that works on Linux, OSX and Windows.

    Read the article

  • Using Session Bean provided data on JSF welcome page

    - by takachgeza
    I use JSF managed beans calling EJB methods that are provide data from database. I want to use some data already on the welcome page of the application. What is the best solution for it? EJBs are injected into JSF managed beans and it looks like the injection is done after executing the constructor. So I am not able to call EJB methods in the constructor. The normal place for EJB call is in the JSF action methods but how to call such a method prior to loding the first page of the application? A possible solution would be to call the EJB method conditionally in a getter that is used on the welcome page, for example: public List getProductList(){ if (this.productList == null) this.productList = myEJB.getProductList(); return this.productList; } Is there any better solution? For example, in some config file?

    Read the article

  • What is the basic pattern for using (N)Hibernate?

    - by Vilx-
    I'm creating a simple Windows Forms application with NHibernate and I'm a bit confused about how I'm supposed to use it. To quote the manual: ISession (NHibernate.ISession) A single-threaded, short-lived object representing a conversation between the application and the persistent store. Wraps an ADO.NET connection. Factory for ITransaction. Holds a mandatory (first-level) cache of persistent objects, used when navigating the object graph or looking up objects by identifier. Now, suppose I have the following scenario: I have a simple classifier which is a MSSQL table with two columns - ID (auto_increment) and Name (nvarchar). To edit this classifier I create a form which contains a single gridview and two buttons - OK and Cancel. The user can nearly directly edit the table in the gridview, and when he hits OK the changes he made are persisted to the DB (or if he hits cancel, nothing happens). Now, I have several questions about how to organize this: What should the lifetime of my ISession be? Should I create a single ISession for my whole application; an ISession for each of my forms (the application is single-threaded MDI); or an ISession for every DB operation/transaction? Does NHibernate offer some kind of built-in dirty tracking or must I do this myself? The manual mentions something like it here and there but does not go into details. How is this done? Is there not a huge overhead? Is it somehow tied with the cache(s) that NHibernate has? What are these caches for? Are they not specific to a single ISession? That is, if I use a seperate ISession for every transaction, won't it break the dirty tracking? How does the built-in dirty tracking detect deleted objects?

    Read the article

  • How to build a web site which gives a sub-domain dynamically to every registered user?

    - by coderex
    Suppose i have a site and i wish to give a sub-domain for each registered users. like my site http://site.com/ and the test-user is a user registered on my site and site want to make sub-domain for that user. Like http://test-user.site.com Like http://test-user1.site.com for test-user1. Hop you understood the requirement. How can i create a sub-domain using my sites back-end. or dynamically while register

    Read the article

  • Understanding colors

    - by Ankur Gupta
    Hello everyone, Kindly point towards theory/material to read for understanding colors and what makes a good color combinations. Mind it that I am not interested in say "Color combinations for web application" etc. More of the lines of say "Colors and humans". Material free to read is what i am looking for. Thanks

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 473 474 475 476 477 478 479 480 481 482 483 484  | Next Page >