Skip to main content


MVC – The King of Design Patterns

mvcking
Model View Controller (MVC) is one of the building blocks of Cocoa and is undoubtedly the most-used design pattern of all. It classifies objects according to their general role in your application and encourages clean separation of code based on role.
The three roles are:
  • Model: The object that holds your application data and defines how to manipulate it. For example, in your application the Model is your Album class.
  • View: The objects that are in charge of the visual representation of the Model and the controls the user can interact with; basically, all the UIViews and their subclasses. In your application the View is represented by your AlbumView class.
  • Controller: The controller is the mediator that coordinates all the work. It accesses the data from the model and displays it with the views, listens to events and manipulates the data as necessary. Can you guess which class is your controller? That’s right: ViewController.


Comments

Popular posts from this blog

Understanding of Size Classes?

Size Classes are an abstraction of how a device should be categorized depending on its screen dimensions. Apple defined two categorizations for both vertical and horizontal sizes called “Regular” and “Compact”. The former specifies a big space, while the latter specifies a small” space. How big or small exactly? Here, “big” and “small” are not intended to be measured in inches. iOS Size Classes Apple has introduced many devices like iPhone, iPad with different screen sizes and resolution. Also after iOS 8 apple has supported multitasking in iPad. So for the developers to develop a common or single UI for all the devices apple has introduced the concept of an adaptive layout by combining auto layout and size classes. What is adaptive layout: The adaptive layout is a method of building the apps based on the size and characteristics of the container instead of a targeting a particular device. We can create a single layout to work on all...

SQLite 3 Procedure & Functions

SQLite 3 Procedure & Functions iOS - SQLite Database SQLite can be used in iOS for handling data. It uses sqlite queries, which makes it easier for those who know SQL. Steps Involved Step 1.  Create a simple  View based application . Step 2.  Select your project file, then select targets and then add  libsqlite3.dylib  library in choose frameworks. Step 3.  Create a new file by selecting File-> New -> File... -> select  Objective C class  and click next. Step 4.  Name the class as  DBManager  with  "sub class of"  as NSObject. Step 5.  Select create. Step 6.  Update  DBManager.h  as follows − SQLite 3 Functions Preview sqlite3_open : This function is used to create and open a database file. It accepts two parameters, where the first one is the database file name, and the second a handler to the database. If the file does n...

What Is a Closure?

Closures are self contained chunks of code that can be passed around and used in your code. Closures can capture and store references to any constants or variables from the context in which they are defined. This is know as closing over those variables, hence the name closures. Closures are use intensively in the Cocoa frameworks – which are used to develop iOS or Mac applications. Functions are a special kind of closures. There are three kinds of closures: global functions  – they have a name and cannot capture any values nested functions  – they have a name and can capture values from their enclosing functions closure expressions  – they don’t have a name and can capture values from their context The thing to keep in mind for the moment is that you already have an intuition about closures. They are almost the same as functions but don’t necessarily have a name. // a closure that has no parameters and return a String var hello: () -> ( String ) = { ...