Search Results

Search found 1449 results on 58 pages for 'oop'.

Page 22/58 | < Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >

• Shadows vs Overloads in VB.NET

  - by serhio

  When we have new in C#, that personally I see only as a workaround to override a property that does not have a virtual/overridable declaration, in VB.NET we have two "concepts" Shadows and Overloads. In which case prefer one to another?

  Read the article

• Logic behind plugin system?

  - by Danijel

  I have an application in PHP (private CMS) that I would like to rewrite and add some new things - I would like to be able to extend my app in an easier way - through plugins But the problem is - I don't know how to achieve "pluggability", how to make system that recognizes plugins and injects them into the app? So, what's the logic of a simple plugin system?

  Read the article

• accessing parent class inherited variable in subclass in PHP

  - by Abhishek

  I have made a class in php which is goind to be inherited by another class in the other folder. when i put echo $this-protectedvariableofclass; //in subclass function it gives no value remember my base class is stored \class\user.php sublass is stored as \model\model_user.php Please help me out Thanks in advance

  Read the article

• How to preallocate an array of class in MATLAB?

  - by Kamran Bigdely Shamloo

  I have an array of objects in MATLAB and I've called their constructors in a loop: antsNumber = 5; for counter = 1: antsNumber ant(counter) = TAnt(source, target); end MATLAB warns me to use preallocation to speed up the process. I do know the benefits of preallocation but I don't know how to do that for objects.

  Read the article

• Add additional content to the middle of string from within a method

  - by Sammy T

  I am working with a log file and I have a method which is creating a generic entry in to the log. The generic log entry looks like this: public StringBuilder GetLogMessage(LogEventType logType, object message) { StringBuilder logEntry = new StringBuilder(); logEntry.AppendFormat("DATE={0} ", DateTime.Now.ToString("dd-MMM-yyyy", new CultureInfo(CommonConfig.EnglishCultureCode))); logEntry.AppendFormat("TIME={0} ", DateTime.Now.ToString("HH:mm:ss", new CultureInfo(CommonConfig.EnglishCultureCode))); logEntry.AppendFormat("ERRORNO={0} ", base.RemoteIPAddress.ToString().Replace(".", string.Empty)); logEntry.AppendFormat("IP={0}", base.RemoteIPAddress.ToString()); logEntry.AppendFormat("LANG={0} ", base.Culture.TwoLetterISOLanguageName); logEntry.AppendFormat("PNR={0} ", this.RecordLocator); logEntry.AppendFormat("AGENT={0} ", base.UserAgent); logEntry.AppendFormat("REF={0} ", base.Referrer); logEntry.AppendFormat("SID={0} ", base.CurrentContext.Session.SessionID); logEntry.AppendFormat("LOGTYPE={0} ", logType.ToString() ); logEntry.AppendFormat("MESSAGE={0} ", message); return logEntry; } What would be the best approach for adding additional parameters before "MESSAGE="? For example if I wanted to add "MODULE=" from a derived class when the GetLogMessage is being run. Would a delegate be what I am looking for or marking the method as virtual and overriding it or do I need something entirely different? Any help would be appreciated.

  Read the article

• Properly design a code editor application

  - by Hemaulo

  I'm working on personal project which is basically a code editor. Imagine standard File menu with menu items New, Open, Save, Save As, Save All, Close, Close All. I'm stuck with proper design. Currently I have: A Document class which represents a document - code editing control, respective tab in tab bar and various properties such as Caption, Filename, IsModified etc. A Documents class which represents all open documents. Contains methods like New, Open(FileName), ... The problem is that I can't figure out which class / menu command is responsible for which tasks. For example, with File-New menu command is simple - call Documents.New and that's it. But what for File-Open? The Documents.Open method expects filename as a parameter. So before calling this method I need to open an file selection dialog, let user select files and for each file call Documents.Open(FileName). Where is best place for this supporting code, in menu command, rewrite Documents.Open and put it there? The same with Save actions. Which is responsible for saving? Is it Documents class which uses Document.Editor.SaveToFile(FileName) or better create Save method in Document class? Somewhere in the middle also need to ask user if he wants to save current document... I'm stuck. Any ideas? Edited: The programming language is Delphi.

  Read the article

• Stuck on Object scope in Java

  - by ivor

  Hello, I'm working my way through an exercise to understand Java, and basically I need to merge the functionality of two classes into one app. I'm stuck on one area though - the referencing of objects across classes. What I have done is set up a gui in one class (test1), and this has a textfield in ie. chatLine = new JTextField(); in another class(test2), I was planning on leaving all the functionality in there and referencing the various gui elements set up in test1 - like this test1.chatLine I understand this level of referencing, I tested this by setting up a test method in the test2 class public static void testpass() { test1.testfield.setText("hello"); } I'm trying to understand how to implement the more complex functionality in test2 class though, specifically this existing code; test1.chatLine.addActionListener(new ActionAdapter() { public void actionPerformed(ActionEvent e) { String s = Game.chatLine.getText(); if (!s.equals("")) { appendToChatBox("OUTGOING: " + s + "\n"); Game.chatLine.selectAll(); // Send the string sendString(s); } } }); This is the bit I'm stuck on, if I should be able to do this - as it's failing on the compile, can I add the actionadapter stuff to the gui element thats sat in test1, but do this from test2 - I'm wondering if I'm trying to do something that's not possible. Hope this makes sense, I'm pretty confused over this - I'm trying to understand how the scope and referencing works. Ideally what i'm trying to achieve is one class that has all the main stuff in, the gui etc, then all the related functionality in the other class, and target the first class's gui elements with the results etc. Any thoughts greatly appreciated.

  Read the article

• How to deal with class composition when components cannot be accessed from the outside?

  - by Chathuranga

  For example if I say I have three classes A, B, and C where B and C have a composition relation ship with A. That means the life of B and C is handled by A, and also B and C cannot access directly from the outside. For some reason my DataService class needs to return objects of B and C as It cant return a object of A as B and C cannot be initialized at the same time. (to be able to initializeC you have to initializeB first). So that I'm returning DataTables from DataService and then inside the class A those data tables are converted to B / C objects. If B and C objects cannot be initialized at the same time is it valid to say that B and C have a composition relationship with A? If its composition is it must to generate A with B and C inside? What is the proper way to handle this sort of a problem? EDIT: Following code explains the way I'm doing it now with DataTables. Example: class A { private List<B> B; private List <C> C; public A() { B= new List<B>(); C= new List<C>(); } public List<B> GetB( DataTable dt) { // Create a B list from dt return B; } } class Presenter { private void Show B() { _View.DataGrid = A.GetB(DataService.GetAListOfB()); } } The actual scenario is I have a class called WageInfo and classes Earning and Deduction having a composition relationship in the design. But for you to generate Deductions first you should Generate earnings and should be saved in a table. Then only you can generate deductions for the earnings to calculate balance wages. Also note that these contained classes have a one to many relationship with the containing class WageInfo. So actually WageInfo has a List<Earnings> and List<Deduction> My initial question was, is it ok if my DataService class returns Deductions / Earnings objects (actually lists) not a WageInfo? Still not clear?

  Read the article

• Check from Constructor if function in child class exists?

  - by ArneRie

  Hi, is it possible to do something like this in PHP 5.2.1? abstract class Test { public function __construct() { if (function_exists('init'): $this->init(); } } If i try this, the function on the subclass is not called?

  Read the article

• How do I extend in my class a Dom element, in mootools

  - by Itay Moav

  I want to create a Class, say MyDiv, which inherits from the original DOM DIV element. Later in my code I would like to use it like that: $('a-container').adopt(new MyDiv('my own set of params')); I am missing the exact syntax to do it.

  Read the article

• Which version of Grady Booch's OOA/D book should I buy?

  - by jackj

  Grady Booch's "Object-Oriented Analysis and Design with Applications" is available brand new in both the 2nd edition (1993) and the 3rd edition (2007), while many used copies of both editions are available. Here are my concerns: 1) The 2nd edition uses C++: given that I just finished reading my first two C++ books (Accelerated C++ and C++ Primer) I guess practical tips can only help, so the 2nd edition is probably best (I think the 3rd edition has absolutely no code). On the other hand, the C++ books I read insist on the importance of using standard C++, whereas Booch's 2nd edition was published before the 1998 standard. 2) The 2nd edition is shorter (608 pages vs. 720) so, I guess, it will be slightly easier to get through. 3) The 3rd edition uses UML 2.0, whereas the 2nd edition is pre-UML. Some reviews say that the notation in the 2nd edition is close enough to UML, so it doesn't matter, but I don't know if I should be worrying about this or not. 4) The 2nd edition is available in good-shape used copies for considerably less than what the 3rd one goes for. Given all the above factors, do you think I should buy the 2nd or the 3rd edition? Recommendations on other books are also welcome but I would prefer it if whoever answers has read at least one of the versions of Booch's book (preferably both!). I have already bought but not read GoF and Riel's books. I also know that I should practice a lot with real-life code. Thanks.

  Read the article

• Is there any way to redeclare a class safely in PHP?

  - by Asif Khan

  We all know the infamous "cannot redeclare class" error. Is there any method to overcome this and actually declare a new class with the same name, or is this impossible in PHP 5?

  Read the article

• Auto-implemented getters and setters vs. public fields

  - by tclem

  I see a lot of example code for C# classes that does this: public class Point { public int x { get; set; } public int y { get; set; } } Or, in older code, the same with an explicit private backing value and without the new auto-implemented properties: public class Point { private int _x; private int _y; public int x { get { return _x; } set { _x = value; } } public int y { get { return _y; } set { _y = value; } } } My question is why. Is there any functional difference between doing the above and just making these members public fields, like below? public class Point { public int x; public int y; } To be clear, I understand the value of getters and setters when you need to do some translation of the underlying data. But in cases where you're just passing the values through, it seems needlessly verbose.

  Read the article

• Question about decorator pattern and the abstract decorator class?

  - by es11

  This question was asked already here, but rather than answering the specific question, descriptions of how the decorator pattern works were given instead. I'd like to ask it again because the answer is not immediately evident to me just by reading how the decorator pattern works (I've read the wikipedia article and the section in the book Head First Design Patterns). Basically, I want to know why an abstract decorator class must be created which implements (or extends) some interface (or abstract class). Why can't all the new "decorated classes" simply implement (or extend) the base abstract object themselves (instead of extending the abstract decorator class)? To make this more concrete I'll use the example from the design patterns book dealing with coffee beverages: There is an abstract component class called Beverage Simple beverage types such as HouseBlend simply extend Beverage To decorate beverage, an abstract CondimentDecorator class is created which extends Beverage and has an instance of Beverage Say we want to add a "milk" condiment, a class Milk is created which extends CondimentDecorator I'd like to understand why we needed the CondimentDecorator class and why the class Milk couldn't have simply extended the Beverage class itself and been passed an instance of Beverage in its constructor. Hopefully this is clear...if not I'd simply like to know why is the abstract decorator class necessary for this pattern? Thanks. Edit: I tried to implement this, omitting the abstract decorator class, and it seems to still work. Is this abstract class present in all descriptions of this pattern simply because it provides a standard interface for all of the new decorated classes?

  Read the article

• Suggest the way to design several classes

  - by Oleg Tarasenko

  Hi, I'm building simple application on as3. Kind of starship game. What I want to do is to create several different star ships. Each one should have different images (different look), different sets of animation (e.g. when it's flying, burning, damaged), different kind of weapon and also different controllers (e.g. one can be managed by user, another one by computer, and I want to be able to reuse same ships for AI controller as well as for users controls). Each ship is created in the following way: Create entity Add spatial Add renderers Add other components.... ...... n. init the ship So what I am trying to do: 1) Create StarShip superclass, to store HP (as every ship has it), store spatial (same reason) 2) Create inherited class for any other ship... (It will contain renderer - (responsible for display part), weapon, set of animations), etc What do you think about such way of composition? Maybe it's better to place everything in super class, and then just create instances using long, long, long constructors like: StarShip(hp:HP, animations:DICT, weapon:Weapon, ....) Need advice

  Read the article

• What problems do you find with this view on domain-driven design?

  - by Bozho

  I just wrote a long (and messy) blogpost about my view on domain-driven design at present day, with frameworks like spring and hibernate massively in use. I'd ask you to spot any problems with my views on the matter - why this won't work, why it isn't giving the benefits of DDD, why it is not a good idea in general. The blogpost is here (I don't think I need to copy-paste it on SO - if you think I should, tell me). I know the question is subjective, but it is aimed at gathering the most predominant opinions. (I'm tagging Java, since the frameworks discussed are Java frameworks)

  Read the article

• Placement of service methods

  - by mhp

  Let's assume I have two service classes with the following methods: GroupService createGroup() deleteGroup() updateGroup() findGroup() UserService createUser() deleteUser() updateUser() findUser() Now, I am thinking about the aesthetics of theses classes. Imagine we want to implement a method which search for all user of a specific group. Which service class is responsible for such a method? I mean, the return value is a user (or maybe a collection of users) but the parameter (which means the name of the group) is a group. So which service class is the better place to put this method in?

  Read the article

• Overload the equals method in java

  - by fastcodejava

  Does anyone overload the equals method in java? The overloaded method will be public boolean equals(final MyClass myClass) This will have the benefit of having the relevant comparison part (guts of the method) in another method. Details are in this blog.

  Read the article

• PHP Serialization Will not work correctly.

  - by stevoo

  Hi, I am developing and doing all the testing on a local machine using PHP Version 5.3.3-1ubuntu9.1 version. The host machine is PHP Version 5.2.15. All the seriliaze arguments are identical. The problems is when i try to login the user on my test local machine i do the following : $user->getByUserId($results['id'],$db); $_SESSION['user'] = serialize($user); which retrieved me and serialize the user. and i just load it back when ever i detect that a session exists $user->LoadFromObject(unserialize($_SESSION['user'])); This works perfectly on my test machine. Just transfered the files on the host to see if i can get a beta version out but i keep on getting Warning: unserialize() expects parameter 1 to be string, object given in /home/gamerent/public_html/beta/includes/header.php on line 19 i have noticed that if i echo the $_SESSION['user'] in both system the test will indeed display me the serializated one but the main one will just show me the object and will not serialize the $user

  Read the article

• Generic overriding tells me this is the same function. Not agree.

  - by serhio

  base class: Class List(Of T) Function Contains(ByVal value As T) As Boolean derived class: Class Bar : List(Of Exception) ' Exception type as example ' Function Contains(Of U)(ByVal value As U) As Boolean compiler tells me that that two are the same, so I need to declare Overloads/new this second function. But I want use U to differentiate the type (one logic) like NullReferenceException, ArgumentNull Exception, etc. but want to leave the base function(no differentiation by type - other logic) as well.

  Read the article

• Why "private" methods in the object oriented ?

  - by pointlesspolitics

  I understand it is a very basic concept in the oops. But still I cannot get my head around. I understood why member variables are private, so class user cannot abuse it by setting up invalid values. But how can this apply to the methods ?

  Read the article

• javascript constructor reset: What is it ?

  - by Sake

  I came across this slide: http://www.slideshare.net/stoyan/javascript-patterns#postComment at page 35: Option 5 + super + constructor reset function inherit(C, P) { var F = function(){}; F.prototype = P.prototype; C.prototype = new F(); C.uber = P.prototype; C.prototype.constructor = C; // WHY ??? } I don't get it. Can anybody please explain what the last line for ? C.prototype.constructor = C; // WHY ??? Thanks

  Read the article

• strategy for observer pattern?

  - by fayer

  I want to use observer pattern for a logging system. We have got logObservers and logObservables. The class that will have to log something will implement iLogObservable and include these methods: private $logObservers = array(); public function addLogObserver($logObserver) { $this->logObservers[] = $logObserver; } public function removeLogObserver($logObserver) { $this->logObservers[] = $logObserver; } public function write($type, $message) { foreach($this->logObservers as $logObserver) { $logObserver->log($level, $message); ; } } Then I noticed, that a lot of classes that will use logging will have these methods and I have to copy paste. So isn't it better to have these methods in a class I call LogObservable or just Log and then use strategy (instantiate this class inside all classes that will have to log). When I change the methods in Log, all logObservables will be affected. However, I have not seen anyone use observer pattern with strategy pattern yet, but it seems to be very efficient and remove the duplications. What do you think?

  Read the article

• Most efficient way to update attribute of one instance

  - by Begbie00

  Hi all - I'm creating an arbitrary number of instances (using for loops and ranges). At some event in the future, I need to change an attribute for only one of the instances. What's the best way to do this? Right now, I'm doing the following: 1) Manage the instances in a list. 2) Iterate through the list to find a key value. 3) Once I find the right object within the list (i.e. key value = value I'm looking for), change whatever attribute I need to change. for Instance within ListofInstances: if Instance.KeyValue == SearchValue: Instance.AttributeToChange = 10 This feels really inefficient: I'm basically iterating over the entire list of instances, even through I only need to change an attribute in one of them. Should I be storing the Instance references in a structure more suitable for random access (e.g. dictionary with KeyValue as the dictionary key?) Is a dictionary any more efficient in this case? Should I be using something else? Thanks, Mike

  Read the article

• C++ Linked List - Reading data from a file with a sentinel

  - by Nick

  So I've done quite a bit of research on this and can't get my output to work correctly. I need to read in data from a file and have it stored into a Linked List. The while loop used should stop once it hits the $$$$$ sentinel. Then I am to display the data (by searching by ID Number[user input]) I am not that far yet I just want to properly display the data and get it read in for right now. My problem is when it displays the data is isn't stopping at the $$$$$ (even if I do "inFile.peek() != EOF and omit the $$$$$) I am still getting an extra garbage record. I know it has something to do with my while loop and how I am creating a new Node but I can't get it to work any other way. Any help would be appreciated. students.txt Nick J Cooley 324123 60 70 80 90 Jay M Hill 412254 70 80 90 100 $$$$$ assign6.h file #pragma once #include <iostream> #include <string> using namespace std; class assign6 { public: assign6(); // constructor void displayStudents(); private: struct Node { string firstName; string midIni; string lastName; int idNum; int sco1; //Test score 1 int sco2; //Test score 2 int sco3; //Test score 3 int sco4; //Test score 4 Node *next; }; Node *head; Node *headPtr; }; assign6Imp.cpp // Implementation File #include "assign6.h" #include <fstream> #include <iostream> #include <string> using namespace std; assign6::assign6() //constructor { ifstream inFile; inFile.open("students.txt"); head = NULL; head = new Node; headPtr = head; while (inFile.peek() != EOF) //reading in from file and storing in linked list { inFile >> head->firstName >> head->midIni >> head->lastName; inFile >> head->idNum; inFile >> head->sco1; inFile >> head->sco2; inFile >> head->sco3; inFile >> head->sco4; if (inFile != "$$$$$") { head->next = NULL; head->next = new Node; head = head->next; } } head->next = NULL; inFile.close(); } void assign6::displayStudents() { int average = 0; for (Node *cur = headPtr; cur != NULL; cur = cur->next) { cout << cur->firstName << " " << cur->midIni << " " << cur->lastName << endl; cout << cur->idNum << endl; average = (cur->sco1 + cur->sco2 + cur->sco3 + cur->sco4)/4; cout << cur->sco1 << " " << cur->sco2 << " " << cur->sco3 << " " << cur->sco4 << " " << "average: " << average << endl; } }

  Read the article

< Previous Page | 18 19 20 21 22 23 24 25 26 27 28 29  | Next Page >