How to delete SKShapeNode in Swift

Tag: xcode,swift,sprite-kit

I'm making a SpriteKit project where one game screen needs to allow the user to draw on the screen. I want to have a "delete all" button and an "undo" button. However, I can't find out how to delete a path anywhere online. Here's how I'm drawing my lines:

var pathToDraw:CGMutablePathRef!
var lineNode:SKShapeNode!

override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {

    let touch = touches.anyObject() as UITouch
    let touchLocation = touch.locationInNode(self)

    pathToDraw = CGPathCreateMutable()
    CGPathMoveToPoint(pathToDraw, nil, touchLocation.x, touchLocation.y)

    lineNode = SKShapeNode()
    lineNode.path = pathToDraw
    lineNode.strokeColor = drawColor
    self.addChild(lineNode)
}

override func touchesMoved(touches: NSSet, withEvent event: UIEvent) {

    let touch = touches.anyObject() as UITouch
    let touchLocation = touch.locationInNode(self)

    CGPathAddLineToPoint(pathToDraw, nil, touchLocation.x, touchLocation.y)
    lineNode.path = pathToDraw   
}

override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {}

But now the problem is how can I delete them? I have tried lineNode.removeFromParent() but it doesn't work. Any ideas?

Best How To :

You can keep track of the SKShapeNodes you draw on the screen in an array. First create a property shapeNodes

var shapeNodes : [SKShapeNode] = []

Add each lineNode to the shapeNodes in touchesBegan

override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {

    //Your code
    shapeNodes.append(lineNode)
}

On pressing delete all button you loop through the shapeNodes array and remove them one by one.

func deleteAllShapeNodes() {

    for node in shapeNodes
    {
        node.removeFromParent()
    }
    shapeNodes.removeAll(keepCapacity: false)
}

For undo, you just have to delete the last node in the shapeNodes array.

 func undo() {
    shapeNodes.last?.removeFromParent()
    shapeNodes.removeLast()
 }

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