Using TouchesMoved in Swift 2 - ios

I'm making a SpriteKit game in XCode using swift. I want to make custom buttons in the menu, and I'm following this tutorial to do it. Everything's working fine except the touchesMoved function.
override func touchesMoved(touches: NSSet, withEvent event: UIEvent) {
var touch: UITouch = touches.allObjects[0] as UITouch
var location: CGPoint = touch.locationInNode(self)
if defaultButton.containsPoint(location) {
activeButton.hidden = false
defaultButton.hidden = true
} else {
activeButton.hidden = true
defaultButton.hidden = false
}
}
Apparently, the "touches.allObjects[0] as UITouch" doesn't work anymore in Swift 2. I've searched for alternatives, but I haven't found any that works. How could I replace that line of code?

For some reason the tutorial is using NSSet rather than Set<UITouch> in touchesMoved. I wonder if they translated the tutorial from Objective-C to Swift, and missed updating them?
func touchesMoved(_ touches: Set<UITouch>,
withEvent event: UIEvent?)
touchesMoved - Apple docs
Notice the touches argument is of type NSSet in your code, and the Apple docs have it as Set<UITouch>.
Once you switch to Set<UITouch>, try using touches.first as! UITouch
Be careful if it can be nil, I'm not familiar with the user input functions on iOS.
If you allow multitouch later you'll need to check the entire Set, rather than just grabbing the first (and only) UITouch element.

The correct way to do it is this:
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
for touch: AnyObject in touches {
let location = touch.locationInNode(self)
if defaultButton.containsPoint(location) {
activeButton.hidden = false
defaultButton.hidden = true
} else {
activeButton.hidden = true
defaultButton.hidden = false
}
}
}

Related

multitouch in iOS [duplicate]

So I've been messing around trying to get the coordinates of touches on the screen. So far I can get the coordinates of one touch with this:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
let touch = touches.anyObject()! as UITouch
let location = touch.locationInView(self.view)
println(location)
}
But when touching with two fingers I only get the coordinates of the first touch. Multi-touch works (I tested with this little tutorial: http://www.techotopia.com/index.php/An_Example_Swift_iOS_8_Touch,_Multitouch_and_Tap_Application). So my question is, how do I get the coordinates of the second (and third, fourth...) touch?
** Updated to Swift 4 and Xcode 9 (8 Oct 2017) **
First of all, remember to enable multi-touch events by setting
self.view.isMultipleTouchEnabled = true
in your UIViewController's code, or using the appropriate storyboard option in Xcode:
Otherwise you'll always get a single touch in touchesBegan (see documentation here).
Then, inside touchesBegan, iterate over the set of touches to get their coordinates:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
for touch in touches {
let location = touch.location(in: self.view)
print(location)
}
}
the given touches argument is a set of detected touches.
You only see one touch because you select one of the touches with :
touches.anyObject() // Selects a random object (touch) from the set
In order to get all touches iterate the given set
for obj in touches.allObjects {
let touch = obj as UITouch
let location = touch.locationInView(self.view)
println(location)
}
You have to iterate over the different touches. That way you can access every touch.
for touch in touches{
//Handle touch
let touchLocation = touch.locationInView(self.view)
}
In Swift 1.2 this has changed, and touchesBegan now provides a Set of NSObjects.
To iterate through them, cast the touches collection as a Set of UITouch objects as follows:
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
var touchSet = touches as! Set<UITouch>
for touch in touchSet{
let location = touch.locationInView(self.view)
println(location)
}
}
For Swift 3, based on #Andrew's answer :
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
let touchSet = touches
for touch in touchSet{
let location = touch.location(in: self.view)
print(location)
}
}
EDIT, My bad, that's not answering your question, had the same problem and someone linked me to this previous answer :
Anyway, I had to change few things to make it works in swift 3, here is my current code :
var fingers = [String?](repeating: nil, count:5)
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesBegan(touches, with: event)
for touch in touches{
let point = touch.location(in: self.view)
for (index,finger) in fingers.enumerated() {
if finger == nil {
fingers[index] = String(format: "%p", touch)
print("finger \(index+1): x=\(point.x) , y=\(point.y)")
break
}
}
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesMoved(touches, with: event)
for touch in touches {
let point = touch.location(in: self.view)
for (index,finger) in fingers.enumerated() {
if let finger = finger, finger == String(format: "%p", touch) {
print("finger \(index+1): x=\(point.x) , y=\(point.y)")
break
}
}
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
super.touchesEnded(touches, with: event)
for touch in touches {
for (index,finger) in fingers.enumerated() {
if let finger = finger, finger == String(format: "%p", touch) {
fingers[index] = nil
break
}
}
}
}
I still have a little problem but I think it's linked to my GestureRecognizer in my code.
But that should do the trick.
It will print you the coordinate of each point in your consol.
In Swift 3,4
Identify touch pointer by its hash:
// SmallDraw
func pointerHashFromTouch(_ touch:UITouch) -> Int {
return Unmanaged.passUnretained(touch).toOpaque().hashValue
}

Exceeding the maximum number of touches makes the program not to call the touchesEnded method?

Ive just started learning programming in general and ran into a problem:
I have read some articles about that the iPhones are only capable of tracking 5 touches or so... But I realised that when I touch the screen with e.g. 7 fingers at once, my program-let stops working.
So, anyone knows, which parts of the code malfunctions when I am touching the screen way too many times at once?
(I am a newbie.)
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
let touch = touches.first!
touchLocation = touch.locationInNode(self)
nrTouches += touches.count
}
override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
nrTouches -= touches.count
}
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
let touch = touches.first!
touchLocation = touch.locationInNode(self)
}
override func update(currentTime: CFTimeInterval) {
if nrTouches > 0 {
touchingLabel.text = "touching"
} else {
touchingLabel.text = "not touching"
}
}
So, in the case I am touching with 7 fingers at once, "touching" will be displayed all the time.
tankyuu
You're missing touchesCancelled, which gets called when the 6th finger is put down:
override func touchesCancelled(touches: Set<UITouch>?, withEvent event: UIEvent?) {
if let touches = touches {
nrTouches -= touches.count // same logic as touchesEnded
}
}
An interesting note: The iPad can handle 11 touch events. More on that here.

Value of type 'UITouch' has no member 'locationInNode'

I'm trying to get location of touch with swift2.1 and get error "Value of type 'UITouch' has no member 'locationInNode'".
here is my code
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
if let touch = touches.first {
let location = touch.locationInNode(self)
print(location)
}
}
I had a look into source and saw that in class UITouch there is only public
func locationInView(view: UIView?) -> CGPoint {
}
is it something I should use or ... ?
As NicolasMiari pointed out in the comment, only if you are using SpriteKit this will work. locationInNode() is a SpriteKit function that helps you find the point in an SKNode.
If you are using "standard" UIKit where you want to get the location of a touch in a view, you should be using locationInView() which takes a view(!) not the controller itself.
class ViewController : UIViewController{
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
if let touch = touches.first {
let location = touch.locationInView(self.view)
print(location)
}
}
}

Overriding touchesBegan in Swift

I am overriding:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent)
in Swift.
I am wondering, is this correct for getting one touch point:
var touchPoint: CGPoint! = event.touchesForView(self)?.anyObject()?.locationInView(self)
Thanks in advance!
As of iOS 8.3, touchesBegan takes a touches parameter which is a Set<NSObject>. It's now Set<UITouch>. So, you would:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
guard let point = touches.first?.location(in: view) else { return }
// use `point` here
}
In previous iOS versions, touchesBegan was defined as a NSSet parameter, as outlined in the question, so you would:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
if let touch = touches.anyObject() as? UITouch {
let touchPoint = touch.locationInView(view)
...
}
}

Detect touch on child node of object in SpriteKit

I have a custom class that is an SKNode, which in turn has several SKSpriteNodes in it. Is there a way I can detect touches on these child SKSpriteNodes from my game scene?
I'm working in swift
override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {
let touch = touches.anyObject() as UITouch
let touchLocation = touch.locationInNode(self)
if([yourSprite containsPoint: touchLocation])
{
//sprite contains touch
}
}
Source: http://www.raywenderlich.com/84434/sprite-kit-swift-tutorial-beginners
Examine Apple's SceneKitVehicle demo. Someone kindly ported it to Swift.
The code you want is in the GameView.swift file. In the GameView you'll see the touchesBegan override. Here's my version of it for Swift 2.1:
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
guard let scene = self.overlaySKScene else {
return
}
let touch = touches.first!
let viewTouchLocation = touch.locationInView(self)
let sceneTouchPoint = scene .convertPointFromView(viewTouchLocation)
let touchedNode = scene.nodeAtPoint(sceneTouchPoint)
if (touchedNode.name == "Play") {
print("play")
}
}
If it's not clear; the GameView is set as the app's view class by way of the Storyboard.
You'll need to compare the location of your Touch to the location of your SKNode
You can get the location of your touch at one of the following methods, using locationInNode():
touchesBegan()
touchesMoved()
touchesEnded()
Swift 5+
If you wish to encapsulate touch logic in a node and deal with it locally, you can simply set interaction to true in the corresponding node.
isUserInteractionEnabled = true
And then, of course, override touchesBegan to your desire.
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {}
If you still wish to receive touches in the scene when touches occur inside a child node, you can, for instance, define a protocol and property for the child node's delegate and set the scene to be it.
e.g:
final class GameScene: SKScene {
private let childNode = ChildNode()
override func didMove(to view: SKView) {
addChild(childNode)
childNode.delegate = self
}
}
extension GameScene: TouchDelegate {}
protocol TouchDelegate {
func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?)
}
final class ChildNode: SKSpriteNode {
var delegate: TouchDelegate?
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
delegate?.touchesBegan(touches, with: event)
}
}

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