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iOS Object-Oriented Swift Class Inheritance Overriding Methods

Duong Nguyen
Duong Nguyen
3,292 Points

Error: EXC_BAD_ACCESS (code = 2, address = 0x7fff4f6c1f98) in my Tower Defense code

I am following the steps in the videos in my Xcode. It showed an error: Error: EXC_BAD_ACCESS (code = 2, address = 0x7fff4f6c1f98)

at line (at the end of the code) let laserTower = LaserTower(x: 2, y: 2)

and I can't seem to get around it. Any help?

My codes:

class Point {

let x: Int

let y: Int

init (x: Int, y: Int) {
    self.x = x
    self.y = y
}

let p1 = Point(x: 0, y:0)

///Returns the surrounding points in range of
///the current one
func points(inRange range: Int = 1) -> [Point] {
    var results = [Point]()
    let lowerBoundOfXRange = x - range
    let upperBoundOfXRange = x + range

    let lowerBoundOfYRange = y - range
    let upperBoundOfYRange = y + range

    for xCoordinate in lowerBoundOfXRange...upperBoundOfXRange {
        for yCoordinate in lowerBoundOfYRange...upperBoundOfYRange {
            let coordinatePoint = Point(x: xCoordinate, y: yCoordinate)
            results.append(coordinatePoint)
        }
    }
    return results
}

}

// Enemies

class Enemy {
    var life: Int = 2
    let position: Point
    init(x: Int, y: Int) {
        self.position = Point(x: x, y: y)
    }
    func decreaseLife(by factor: Int) {
    life -= factor
    }
}

class SuperEnemy: Enemy {

    let isSuper: Bool = true

    override init(x: Int, y: Int) {
        super.init(x: x, y: y)
        self.life = 50
    }
}

//Towers class Tower { let position: Point var range: Int = 1 var strength: Int = 1

    init (x: Int, y: Int) {
        self.position = Point(x: x, y: y)
    }

func fire(at enemy: Enemy) {
        if isInRange(of: enemy) {
            enemy.decreaseLife(by: strength)
            print("Gotcha!")
        } else {
            print("Darn! Out of Range!")
        }
        }
    func isInRange(of enemy: Enemy) -> Bool {
        let availablePositions = position.points(inRange: range)
        for point in availablePositions {
            if point.x == enemy.position.x && point.y == enemy.position.y {
                return true
            }
        }
        return false
    }
}

class LaserTower: Tower{ override init(x: Int, y: Int) { super.init(x: x, y: y) self.range = 100 self.strength = 100 }

override func fire(at enemy: Enemy) {
    while enemy.life >= 0 {
    enemy.decreaseLife(by: strength)
    }
    print("Enemy destroyed!")
}

}

let laserTower = LaserTower(x: 2, y: 2)

let enemy = Enemy(x: 1, y: 1)

let tower = Tower(x: 0, y: 0)

let superEnemy = SuperEnemy (x:1, y: 1)

superEnemy.life

tower.fire(at: enemy)

tower.fire(at: superEnemy)

laserTower.fire(at: superEnemy)