December 21, 2024
Artwork instance methods
The instance methods of Artwork are as follows:
height
"Answer the height of the receiver."
^height
height: aNumber
"Set the height of the receiver to aNumber (a number
of cms). Answer the receiver."
height := aNumber
initialize
"Initialize the receiver with title set to the
string 'untitled'. Answer the receiver."
self title: 'untitled'
media
"Answer the media of the receiver."
^media
media: aString
"Set the media of the receiver to aString (a
string). Answer the receiver."
media := aString
price
"Answer the price of the receiver."
^price
price: aFloat
"Set the price of the receiver to aFloat (a float).
Answer the receiver"
price := aFloat
size
"Answer with a string that indicates the height
of
the receiver multiplied by the width of the receiver
in cms."
^self height printString,' cm ',' x ', self width
printString ,' cm'
title
"Answer the title of the receiver."
^title
title: aString
"Set the title of the receiver to aString ( a
string). Answer the receiver"
title := aString
width
"Answer the width of the receiver."
^width
width: aNumber
"Set the width of the receiver to a Number ( a
number of cms). Answer the receiver."
width := aNumber
yearCreated
"Answer the yearCreated of the receiver."
^yearCreated
yearCreated: aString
"Set the yearCreated of the receiver to aString
(a
String representing a year eg '1998'). Answer
the receiver."
yearCreated := aString
There is nothing too dramatic going on here. Each getter returns the value of the object referenced by the receiver's instance variable and the setters use assignment to set the instance variable to the object supplied as the argument. The initialize method sets the instance variable title of the receiver to a string object, in this case 'untitled'. The reasoning for this shouldn't concern you too much at this stage.
However both the initialize and size methods require us to consider the concept of self.
Next page » self
Previous page « Artwork protocol
⇑ Up to top of page