All about Properties in swift

just an illustration from somewhere :p

First , let me talk about a property . Suppose if we need to change or access an iVar in your class using an object of your class, then there should be getter and setter methods assigned to the iVar. A property is used mainly when other objects need to change or access the ivars in your object, without manually defining getters and setters, or using @property (in objective - c).

In objective-c, @property declares a property in your class header. Here is an example:

@property (nonatomic, retain) NSString *myString;

@synthesize creates your setter and getter for your property (accessor methods). Without synthesize you have to write your own setter and getter implemention, like getMyString or setMyString (capitalize the first character of your property).

So, the above property declaration is equivalent to:

- (NSString*)myString {}
- (void)setMyString:(NSString*)newValue {}

Properties can be further classified into Stored properties and Computed properties.

Stored Property vs Computed property

Stored properties store constant and variable values as part of an instance, whereas computed properties calculate (rather than store) a value.