Contact method for a frame - ios

Question

I am trying to implement a contact method to know when my player block has touched the yellow frame. Below is the code I have so far. When i drag the player block to the yellow frames nothing happens.
import SpriteKit
import iAd
struct BitMask {
static let player: UInt32 = 0x1 << 0
static let obstacle: UInt32 = 0x1 << 1
static let frame: UInt32 = 0x1 << 2
}
class GameScene: SKScene, SKPhysicsContactDelegate {
let player = SKShapeNode(rectOfSize: CGSize(width: 30, height: 30))
override func didMoveToView(view: SKView) {
super.didMoveToView(view)
// setup scene's physics body (setup the walls)
physicsBody = SKPhysicsBody(edgeLoopFromRect: frame)
// get current screen size
let screenSize: CGRect = UIScreen.mainScreen().bounds
print("screenWidth: \(screenSize.width) screenHeight: \(screenSize.height)")
// setup play scene
let playScreen = SKSpriteNode(color: .clearColor(), size: CGSize(width: 370, height: 370))
// y position adjustment
let yFrame = 65
playScreen.position = CGPoint(x: frame.midX, y: frame.midY - CGFloat(yFrame))
// create the rectangle which will represent physics body.
let rect = CGRect(origin: CGPoint(x: -playScreen.size.width/2, y: -playScreen.size.height/2), size: playScreen.size)
// apply physics conditions to the play scene
playScreen.physicsBody = SKPhysicsBody(edgeLoopFromRect: rect)
playScreen.physicsBody?.friction = 0
// add play scene to the frame
addChild(playScreen)
let playerScreenFrame = SKShapeNode(rectOfSize: CGSize(width: playScreen.size.width, height: playScreen.size.height))
playerScreenFrame.position = CGPoint(x: frame.midX, y: frame.midY - CGFloat(yFrame))
playerScreenFrame.fillColor = .clearColor()
playerScreenFrame.strokeColor = UIColor(rgba: "#E9BD00")
playerScreenFrame.lineWidth = 3;
addChild(playerScreenFrame)
let bottomRect = CGRectMake(frame.midX, frame.midY - CGFloat(yFrame), playScreen.size.width, playScreen.size.height)
let bottom = SKNode()
bottom.physicsBody = SKPhysicsBody(edgeLoopFromRect: bottomRect)
addChild(bottom)
bottom.physicsBody!.categoryBitMask = BitMask.frame
bottom.physicsBody!.contactTestBitMask = BitMask.player
bottom.physicsBody!.collisionBitMask = BitMask.player
// set up player block
player.name = "player"
player.fillColor = UIColor(rgba: "#E9BD00")
player.strokeColor = .blackColor()
player.position = CGPoint(x:frame.size.width/2, y: frame.size.height/2 - CGFloat(yFrame))
player.physicsBody = SKPhysicsBody(rectangleOfSize: CGSize(width: 30, height: 30))
player.physicsBody!.dynamic = false
player.physicsBody!.friction = 0
player.physicsBody!.affectedByGravity = false
player.physicsBody!.allowsRotation = false
addChild(player)
player.physicsBody!.categoryBitMask = BitMask.player
player.physicsBody!.contactTestBitMask = BitMask.obstacle | BitMask.frame
player.physicsBody!.collisionBitMask = BitMask.obstacle | BitMask.frame
// set gravity to 0
physicsWorld.gravity = CGVectorMake(0,0)
// set the scene as the delegate to be notified when two bodies collide
physicsWorld.contactDelegate = self
}
my contact method is as follows:
func didBeginContact(contact: SKPhysicsContact) {
var firstBody: SKPhysicsBody
var secondBody: SKPhysicsBody
if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
firstBody = contact.bodyA
secondBody = contact.bodyB
} else {
firstBody = contact.bodyB
secondBody = contact.bodyA
}
if (firstBody.categoryBitMask == BitMask.player) && (secondBody.categoryBitMask == BitMask.obstacle) {
// do your thing
print("Player contacted with obstacle")
self.view?.paused = true
}
if (firstBody.categoryBitMask == BitMask.player) && (secondBody.categoryBitMask == BitMask.frame) {
// do your thing
print("Player contacted with frame")
self.view?.paused = true
}
}

Answer 1

Currently you are trying to check for contact between two static bodies, but SpriteKit will not generate any contact events unless at least one body is dynamic.
In your case, the reason for this is related to the fact that edge-based physics bodies are static by default, and your player is static as well, means no contacts.
To fix this, you should set dynamic property on player's physics body to true, like this:
player.physicsBody!.dynamic = true