How can I determine if two UIImageViews's have touched each other? I'm trying to make it realize they've touched each other and then add some code inside if they did.
Hope someone can help, thanks!
I have already tried
if (newArea.frame.intersects(yolo.frame)) {
print("ok")
}
You can check if UIImageViews are overlapping like that:
if img1.bounds.contains(img2.bounds)
{
print("overlapped")
}
A proper way to do this, without depending on the view hierarchy is to use convertRect.
let r1 = newArea.superview.convert(newArea.frame, to: nil)
let r2 = yolo.superview.convert(yolo.frame, to: nil)
if r1.intersects(r2) { stuff() }
This converts both frames to screen coordinates and then checks the intersection, before they were local coordinates of superviews.
Related
I'm writing an app for Apple Watch using SpriteKit, so I don't have access to functions like touchesBegan and I have to use a WKTapGestureRecognizer to detect taps, no big deal, but I have issues detecting taps on a node.
In my InterfaceController I have:
#IBAction func handleTap(tapGestureRecognizer: WKTapGestureRecognizer){
scene?.didTap(tapGesture: tapGestureRecognizer)
}
And in my Scene file I have
func didTap(tapGesture:WKTapGestureRecognizer) {
let position = tapGesture.locationInObject()
let hitNodes = self.nodes(at: position)
if hitNodes.contains(labelNode) {
labelNode.text = "tapped!"
}
Problem is the Tap Gesture Recognizer gives me the absolute coordinates of the touch point (for example 11.0, 5,0) while my node is positioned relatively to the center of the screen (so its position is -0.99,-11.29 even though is at the center of the screen) therefore the tap is hitting the node not when actually tapping it, but when I tap on the top left of the screen. I searched everywhere and it looks like this is the way to do it yet I don't find people having the same issues. The node has been added via the editor. What am I doing wrong?
So you have the right idea. You are getting this wrong because hitNodes is an array of SKNodes. Those are newly created. So when you use hitNodes.contains the addresses of the labelNode and the address of the newly created SKNode that is being compared would be completely different. Therefore it would never be tapped.
Here's what I would do. This would be in my Scene File. Your InterfaceController class is correct.
func didTap(tapGesture:WKTapGestureRecognizer) {
let position = tapGesture.locationInObject()
if labelNode.contains(position) {
labelNode.text = "tapped!"
}
}
OR another way would be this. I like this way because you only have one function which would be in the WKInterfaceControlller And you would need no functions in your Scene File.
#IBAction func tapOnScreenAct(_ sender: WKGestureRecognizer) {
if scene.labelNode.contains(sender.locationInObject()) {
scene.labelNode.text = "tapped!"
}
}
Either way, both should work. Let me know if you have any more questions or clarifications.
So i have 4 vStacks, each containing 9 ImageViews. Each ImageView represents one Card, alpha 0 is default. When a Card is Detected (with ARKit), my code sets the ImageView to alpha 1 so the user can see that the card has been scanned.
Now: I want to implement that when the user clicks on one of the ImageViews, an alert should pop up asking the user if he is sure he wants to delete the scanned card. My problem is, I have no idea what the best practice is to get the information that the card has been tapped and how to delete it without hardcoding.
In ViewDidLoad i set the images into the ImageVies like This:
//This repeats for all 36 ImageViews
imgView1.image = UIImage(named: "Eichel_6")
imgView2.image = UIImage(named: "Eichel_7")
/*When a image is detected with ARKit, this is what happens. Basically
*it pushes the corresponding reference name to an array called
* scannedCards, handles them, and removes them afterwards.
* spielPoints = gamepoints/points, spielmodus = gamemode
*/
func updateLabel() {
//print all cards in scanned cards
for card in scannedCards {
points += (DataController.shared.spielpoints[DataController.shared.spielmodus!]![card]! * DataController.shared.multCalculator[DataController.shared.spielmodus!]!)
}
scannedCards.removeAll()
}
I am a new to coding, I would be grateful if you correct me if my code snippets are bad, beside my question. Thank you in advance.
As has already been mentioned in comments, you should use a UICollectionView for this kind of work. #Fogmeister has promised to add an answer concerning that later, so I won't do that. But I can answer the actual question, even though it's not what you should do.
From your code I can see that you probably have outlets for all your imageViews (imgView1 ... imgView36) and set each image manually. To detect taps on any of these, you could do something like this:
func viewDidLoad(){
super.viewDidLoad()
let allImageViews = [imageView1, imageView2, .... imageView36]
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(didTapImageView(gesture:)))
allImageViews.forEach({$0.addGestureRecognizer(tapGestureRecognizer)})
}
#objc func didTapImageView(gesture:UITapGestureRecognizer){
guard let imageView = gesture.view as? UIImageView else { return }
//Here you can put code that will happen regardless of which imageView was tapped.
imageView.alpha = 0.0
//If you need to know exactly which imageView was tapped, you can just check
if imageView == self.imageView1{
//Do stuff only for imageView1
}else if imageView == self.imageView2{
//...
}//....
}
Again, this is not very good practice. If you go for UICollectionView instead, you don't have to have outlets for all your imageViews and you don't have to create a gestureRecognizer for handling events. But still, I hope this helped you understand general gestures better.
I'm very new to Swift, and trying to create an app where Swiping between pages works normally but also involves a change in background color based on swipe distance.
Consequently, I want to "hijack" the swipe gesture, so I can add some behavior to it. The best I can find for how to do that is this question/answer.
Translating the code from the chosen answer into Swift 3, I added the following code to my RootViewController's viewDidLoad function:
for subview in (pageViewController?.view.subviews)!{
if let coercedView = subview as? UIScrollView {
coercedView.delegate = (self as! UIScrollViewDelegate)
}
}
My impression was that the above code would let me delegate functions (such as scrollViewDidScroll to the class in which I'm writing the above code, such that I can define that function, call super.scrollViewDidScroll, and then add any other functionality I want.
Unfortunately, the above code, which doesn't throw any compilation errors, does throw an error when I try to build the app:
Could not cast value of type 'My_App.RootViewController' (0x102cbf740) to 'UIScrollViewDelegate' (0x1052b2b00).
Moreover, when I try to write override func scrollViewDidScroll in my class, I get a compilation error telling me the function doesn't exist to override, which makes me think even if I got past the error, it wouldn't get called, and this isn't the right way to handle this issue.
I'm sorry this is such a noobish question, but I'm really quite confused about the basic architecture of how to solve this, and whether I understand the given answer correctly, and what's going wrong.
Am I interpreting delegate and that answer correctly?
Am I delegating to the correct object? (Is that the right terminology here?)
Is there a better way to handle this?
Am I coercing/casting improperly? Should I instead do:
view.delegate = (SomeHandMadeViewDelegateWhichDefinesScrollViewDidScroll as! UIScrollViewDelegate)
or something similar/different (another nested casting with let coercedSelf = self as? UIScrollViewDelegate or something?
Thanks!
If I understand your question correctly, you want to catch some scroll position and stuff right ? Then do
class RootViewController {
// Your stuff
for subview in pageViewController!.view.subviews {
if let coercedView = subview as? UIScrollView {
coercedView.delegate = self
}
}
extension RootViewController : UIScrollViewDelegate {
// Your scrollView stuff there
}
I decided to animate my objects manually and therefore made an extension for UIView class:
public extension UIView{
func slideOut(){
UIView.animateWithDuration(0.5, animations: { self.frame.origin.x = -self.frame.width }, completion: finishedDisposing)
}
func finishedDisposing(successfully: Bool){
if !successfully{
((UIApplication.sharedApplication().delegate as! AppDelegate).window!.rootViewController as! VC).showSystemMessage("Failed to dispose one or more subviews from superview", ofType: .NOTICE)
}
responder.viewDisposed()
}
}
Which works nice and I have no problems about it, BUT I have a method in VC (Custom UIViewController) viewDisposed() which is called whenever a view slides out of sight and it has such an implementation:
func viewDisposed() {
disposed++
print("Updated disposed: \(disposed) / \(self.view.subviews.count)")
if disposed == self.view.subviews.count - 1{
delegate.vcFinishedDisposing()
}
}
It shows that self.view.subviews contains all my custom views + 3 more (UIView, _UILayoutGuide x 2). They do extend UIView although do not callresponder.viewDisposed method. My decision was to figure out how to get classes of each subview and Mirror(reflecting: subView).subjectType if I print it does it wonderfully. Is there any way to actually compare this to anything or, better, get String representation? Basically, I want you to help me create a method which would create a stack of subviews which are not of type UIView (only subClasses) nor _UILayoutGuide. Thank you!
You'd probably be better off directly creating an array of just the subviews you care about, instead of starting with all subviews and trying to filter out the ones you don't care about. Those layout guides weren't always there—they were added in iOS 7. Who knows what else Apple will add in the future?
Anyway:
let mySubviews = view.subviews.filter {
!["UIView", "_UILayoutGuide"].contains(NSStringFromClass($0.dynamicType))
}
I am trying to delete the objects after it go outside the scene so so i can extenuate ram consumption
I should put the code i have tried but i dont know how to begin so i have nothing to put here sorry
EDIT
Or maybe i should detect if the object inside the view and delete it if not how i can know if the object is inside the view ?
There is a convenient method which checks whether two CGRects intersect each other or not
You can do something like this
if( CGRectIntersectsRect(object.frame, view.frame) ) {
// Don't delete your object
} else {
// Delete your object as it is not in your view
}
I hope this helps :)
You can check in different ways if node is off-screen, and that depends on how you move nodes.
First method :
if (!intersectsNode(yourNode)) {
// node is off-screen
}
To enumerate nodes you can use :
- enumerateChildNodesWithName:usingBlock: To access all nodes in a node tree read this.
Another way is to use actions:
let move = SKAction.moveTo(location: offScreenLocation, duration: 5)
let remove = SKAction.runBlock({yourNode.removeFromParent()})
let sequence = SKAction.sequence([move,remove])
yourNode.runAction(sequence, withKey:"moving") //Use action with key, to cancel the action if needed
Third method would be to use contact detection.