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Start your free trialJacob Carroll
5,957 PointsCode Challenge: Swift Recap Part: 2 (HELP)
Dear Answers,
Can some help me understand how to solve this?
As my mind is rusty with this type of info.
Thanks, JC
1 Answer
Miguel Angel Flores Izquierdo
2,275 Pointsclass Point {
var x: Int
var y: Int
init(x: Int, y: Int){
self.x = x
self.y = y
}
}
class Machine {
var location: Point
init() {
self.location = Point(x: 0, y: 0)
}
func move(direction: String) {
print("Do nothing! Im a machine!")
}
}
class Robot: Machine{
override init()
{
super.init()
self.location = Point(x: 0, y: 0)
}
override func move(direction: String) {
switch direction{
case "Up":
location.y += 1
case "Down":
location.y -= 1
case "Right":
location.x += 1
case "Left":
location.x -= 1
default:
print("Not a valid command!")
break
}
}
}
this is my solution to the challenge, basically you got to create the subclass Robot, then as we know there are 2 steps in creating a subclass
- initialize all subclass properties (in this case Robot)
- initialize all superclass properties (in this case Machine)
since i did not add any properties the "override init()" just initializes the properties from Machine that is the location property.
the task is to override the Move method (also called function) on the Robot subclass so we call the method "override func move(direction: String) {". then proceed to add the code to move the location of the robot depending the value of an String var called "direction". if it goes "Up", Y value of location increases by 1 and a "Down" value decreases the value of Y by 1.
you cant test this code in a playground (i used Xcode 7.3) adding these lines below the code
var robot = Robot ()
robot.location
robot.move("Up")
robot.location
Niilo Pirttijärvi
Courses Plus Student 2,354 PointsNiilo Pirttijärvi
Courses Plus Student 2,354 PointsHi, Could you open up a little bit what this part of the code does and especially why is it needed? override init() { super.init() self.location = Point(x: 0, y: 0) } Since the subclass Robot inherits everything from superclass Machine, why does it not inherit its location and initialisation as well?