oop

What's an easy way to set up object communication in Obj-C?

I am trying to send a slider value from a controller object to a method of a model object. The later is implemented in the separate file and I have appropriate headers. I think the problem is that I am not sure how to instantiate the receiver in order to produce a working method for the controller. Here is the controller's method. -(I...

How to handle the pylint message: Warning: Method could be a function

Being new to Python, I decided to get some feedback on a class I'd written ASAP so I ran it against pylint. Is the message it gave "Warning: Method could be a function" telling me that it would be better to move this method out of the class because it doesn't use any instance variables? In c# I would make this a static method. What's the...

easy object persistence strategy - hibernate?

Hi! I'm doing a Java software-project at my university that mainly is about storing data-sets (management of software tests). The first thing I thought of was a simple SQL DB, however the necessary DB scheme is not available for now (let's say the project is stupid but there's no choice). Is a persistency framework like Hibernate able...

How could I dynamically change the class of an object from a parent's method ?

I have a class called Report. I have several classes that inherit from report, ClientReport, ClientVisitReport... class Report { ... public function load($id) { ... } } class ClientReport extends Report { ... public function load($id) { parent::load($id); ... } } class ClientVisitReport ex...

Organizing multi level aggregate object or composite

Hye! I have Aggregate object that have more than one level. Aggregate root is Network object and it have collection of Nodes and Links. Node and Link have collection of Segments, and Segment have collection of Lanes. My domain is traffic network and this is only part of this aggregate: public class Network { private List<Node> nodes; ...

Lua and C++: separation of duties

Please help to classify ways of organizing C++/Lua game code and to separate their duties. What are the most convenient ways, which one do you use? For example, Lua can be used for initializing C++ objects only or at every game loop iteration. It can be used for game logic only or for graphics, too. Some game engines provide full contro...

Why a new instance uses logger from old instances?

I generate 2 instances in this way: gameManager manager1 = new CTManager(owner,players1,"en"); manager1.start(); gameManager manager2 = new CTManager(owner,players2,"en"); manager2.start(); The start() method of the gameManager looks like that: void start() { game.start(); } When I create the game instance I cre...

When should methods be made private?

There are lots of times where I'm not sure whether a particular method should be made private or not. For example, I'm building a class right now, which, is responsible for generating a report. This class has a buildReport method and several methods which collect the necessary data for buildReport. // single public method // uses a set...

How do you keep application logic separate from UI when UI components have built-in functionality?

I know it's important to keep user interface code separated from domain code--the application is easier to understand, maintain, change, and (sometimes) isolate bugs. But here's my mental block ... Delphi comes with components with methods that do what I want, e.g., a RichText Memo component lets me work with rich text. Other components...

OOP + MVC advice on Member Controller

Hi, I am trying to follow good practices as much as possible while I'm learning using OOP in an MVC structure, so i'm turning to you guys for a bit of advice on something which is bothering me a little here. I am writing a site where I will have a number of different forms for members to fill in (mainly data about themselves), so i've ...

Concrete Types or Interfaces for return types?

Today I came to a fundamental paradox of the object programming style, concrete types or interfaces. Whats the better election for a method's return type: a concrete type or an interface? In most cases, I tend to use concrete types as the return type for methods. because I believe that an concrete type is more flexible for further use ...

How should I declare default values for instance variables in Python?

Should I give my class members default values like this: class Foo: num = 1 or like this? class Foo: def __init__(self): self.num = 1 In this question I discovered that in both cases, bar = Foo() bar.num += 1 is a well-defined operation. I understand that the first method will give me a class variable while the ...

Recommendation for tool/framework that follows the naked objects pattern?

I am searching for a tool/framework that follows the naked objects pattern and is written in Java. I know about tools like for instance JMatter, Naked Objects and Domain Object Explorer. That's not exactly what I am searching for, though. Open source would be great, but doesn't need to be. My intention is to use that tool/framework for ...

Advice on handling widgets for different types of data (MVC)

Hello, I have a few widgets I need to show on a site - they are all relating to different types of data (e.g user, house). Each type of data and its relations is represented in specific models, but as far as a controller or helper is concerned, is it an ok plan to have a generic Widget controller/helper which generates the necessary widg...

A bit confused about OOP and PHP.

Hello I have programmed with procedural style a lot before and in these few months I have decided to go OOP. Im a bit confused about OOP and PHP. Lets say I have Categories table and Pages table in my database. I would like to do a page-class and a category-class. Lets say I would have a page that showed information about the categor...

Coming from a class diagram to a dialog window

Hello, I have a class diagram ("Customer") with some private and public attributes as well as some operations. Now I want to model a dialog (GUI) for editing this customer. The window represents the class Customer and some drop downs and checkboxes the attributes. The operations ("save", "refresh") are represented by buttons. Design Qu...

Can I refer to an object in its constructor?

Can I do the following? public Manager(String userName) { game = new Game(userName); game.addManager(this); } The problem is that I refer to an object (this) in its constructor (before it was actually created). ...

best PHP programming approach?

Hello guys, i guess that many of us has acceptable years of experience in PHP programming, me myself got 5 years programming in PHP since in University (not very solid), i just want to gather some suggestion here, what is better approach in PHP OOP? Since there is a lot of PHP framework out there as well as javascript framework, can a...

N-Tiered application design tool

I'm beginning the design of a medium-sized web application. I usually like to design from the top down, i.e., start at the highest level and design my way down. I am planning to have the following layers: Presentation (PHP/Ajax) Business Logic Data Access Database Now I'd like to start sketching out the major objects in each layer a...

Explain Type Classes in Haskell

Hi, I am a C++ / Java programmer and the main paradigm I happen to use in everyday programming is OOP. In some thread I read a comment that Type classes are more intuitive in nature than OOP. Can someone explain the concept of type classes in simple words so that an OOP guy like me can understand it? ...