Problems using long hold & single tap in game together - objective-c

Question

I'm making a game with two methods of moving. When tapping the screen the player moves up. The game world also moves towards the player looking like the bird is flying forward. When the user holds down the on the screen the player will start flying forward in its position. When the player doesn't touch the screen at all, the player falls (almost like flappy bird).
The game worked fine and smooth until I added the long press method. Because one second is too short, it gets detected as a tap. So when I tap the screen fast 2 times the long press method gets called as well. So I'm thinking there must be another way instead of using long press gesture?
Is there any way to programmatically detect touch up inside and touch and hold in spritekit? I know you could do this in UIKit singleview applications on buttons.
But I need to make it work anywhere on the screen and not just from tapping a button.
I'm using Spritekit as game technology and Xcode as Platform.
Any ideas?

Answer 1

Here is a full working solution for you. Tap to jump the block, hold the screen to move forward. when you touch a wall you will reset position.
Swift3:
class Bird: SKSpriteNode {
private let flyUpImpulse = CGVector(dx: 0, dy: 20)
private let flyForwardForce = CGVector(dx: 100, dy: 0)
// var pb: SKPhysicsBody { return self.physicsBody! }
func initialize() {
color = .blue
size = CGSize(width: 50, height: 50)
physicsBody = SKPhysicsBody(rectangleOf: size)
physicsBody!.categoryBitMask = UInt32(1)
}
func flyUp() {
physicsBody!.applyImpulse(flyUpImpulse)
}
func flyForward() {
physicsBody!.applyForce(flyForwardForce)
}
func resetPosition() {
guard let scene = self.scene else {
print("reset position failed: bird has not been added to scene yet!")
return
}
run(.move(to: CGPoint(x: scene.frame.minX + 50, y: scene.frame.midY), duration: 0))
physicsBody!.velocity = CGVector.zero
}
}
class GameScene: SKScene, SKPhysicsContactDelegate {
enum ControlToDo { case tap, longPress, none }
var controlToDo = ControlToDo.none
// How many frames we have to release screen in order to recognize a "tap".
// Less frames will give a faster response time, but may also give incorrect input:
let tapThreshold = 10
var isTouchingScreen = false
var frameCountSinceFirstTouch = 0
let bird = Bird()
// Scene setup:
override func didMove(to view: SKView) {
removeAllChildren() // Remove this from your actual project.
anchorPoint = CGPoint(x: 0.5, y: 0.5)
physicsBody = SKPhysicsBody(edgeLoopFrom: frame)
physicsBody!.categoryBitMask = UInt32(2)
physicsBody!.contactTestBitMask = UInt32(1)
physicsWorld.gravity = CGVector(dx: 0, dy: -2)
physicsWorld.contactDelegate = self
bird.initialize()
addChild(bird)
}
// Touch handling stuff:
func tap() {
bird.flyUp()
controlToDo = .none
}
func longPress() {
bird.flyForward()
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
isTouchingScreen = true
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
isTouchingScreen = false
if frameCountSinceFirstTouch > tapThreshold {
controlToDo = .none
frameCountSinceFirstTouch = 0
}
else if frameCountSinceFirstTouch < tapThreshold {
controlToDo = .tap
frameCountSinceFirstTouch = 0
}
}
override func update(_ currentTime: TimeInterval) {
// Increase counter if touching the screen:
if isTouchingScreen {
frameCountSinceFirstTouch += 1
}
// If we have held the screen for long enough, do a longPress:
if frameCountSinceFirstTouch > tapThreshold {
controlToDo = .longPress
}
switch controlToDo {
case .tap: tap()
case .longPress: longPress()
case .none: break
}
}
// Reset positon on touch of wall:
func didBegin(_ contact: SKPhysicsContact) {
bird.resetPosition()
}
}
Objective C:
// MAKE SURE YOU HAVE <SKPhysicsContactDelegate> in your .h file!
#import "GameScene.h"
#implementation GameScene {
SKSpriteNode *_bird;
/// 1 is tap, 2 is longpress (i couldn't figure out how to compare strings, or do an enum)
int _controlToDo;
CGFloat _tapThreshold;
CGFloat _frameCountSinceFirstTouch;
Boolean _isTouchingScreen;
}
- (void) setupProperties {
_controlToDo = 0;
_tapThreshold = 10;
_isTouchingScreen = false;
_frameCountSinceFirstTouch = 0;
}
- (void) setupScene {
self.anchorPoint = CGPointMake(0.5, 0.5);
[self removeAllChildren];
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame];
self.physicsBody.categoryBitMask = 2;
self.physicsBody.contactTestBitMask = 1;
self.physicsWorld.gravity = CGVectorMake(0, -2);
self.physicsWorld.contactDelegate = self;
_bird = [SKSpriteNode spriteNodeWithColor:[UIColor blueColor] size:CGSizeMake(50, 50)];
_bird.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:_bird.size];
_bird.physicsBody.categoryBitMask = 1;
[self addChild:_bird];
}
- (void) birdResetPosition {
CGFloat min = 0 - (self.size.width / 2) + (_bird.size.width / 2) + 5;
CGPoint center = CGPointMake(min, 0);
SKAction *movement = [SKAction moveTo:center duration:0];
[_bird runAction:movement];
}
- (void)didMoveToView:(SKView *)view {
[self setupProperties];
[self setupScene];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
_isTouchingScreen = true;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
_isTouchingScreen = false;
if (_frameCountSinceFirstTouch > _tapThreshold) {
_controlToDo = 0;
}
else if (_frameCountSinceFirstTouch < _tapThreshold) {
_controlToDo = 1;
}
_frameCountSinceFirstTouch = 0;
}
-(void)update:(CFTimeInterval)currentTime {
// Increase counter if touching the screen:
if (_isTouchingScreen == true) {
_frameCountSinceFirstTouch += 1;
}
// If we have held the screen for long enough, do a longPress:
if (_frameCountSinceFirstTouch > _tapThreshold) {
_controlToDo = 2;
}
// Bird fly up:
if (_controlToDo == 1) {
[_bird.physicsBody applyImpulse:CGVectorMake(0, 20)];
_controlToDo = 0;
}
// Bird fly forward:
else if (_controlToDo == 2) {
[_bird.physicsBody applyForce:CGVectorMake(100, 0)];
}
}
- (void) didBeginContact:(SKPhysicsContact *)contact {
[self birdResetPosition];
_bird.physicsBody.velocity = CGVectorMake(0, 0);
}
#end

Answer 2

All SKNodes have access to touch events, you just need to enable userInteractionEnabled
By default, this is set to false, but if you are using an SKS file, then the SKS default is set to true
As long as you do not have any other node enabled, when you touch the scene, it will fire for the scene.
To get a hold event going, I would recommend using SKAction's on your scene.
Basically, we want to wait for a specific time period, then fire the event
If at any point the finger is removed, then we remove the action, not firing your event.
Swift:
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
let wait = SKAction.wait(forDuration:1)
let beginHoldEvent = SKAction(run:{//function to start hold event})
run(SKAction.sequence([wait,beginHoldEvent],withKey:"holding")
}
override func touchesEnded(touches: NSSet, withEvent event: UIEvent) {
guard let _ = action(forKey:"holding") else {return}
removeAction(forKey:"holding")
//do single click event
}
Objective C:
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
void (^holdBlock)(void) = ^{
//do holding code here
};
SKAction* wait = [SKAction waitForDuration:1];
SKAction* beginHoldEvent = [SKAction runBlock:holdBlock];
SKAction* seq = [SKAction sequence:#[wait,beghinHoldEvent]];
[self runAction:seq withKey:#"holding"];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if([self actionForKey:#"holding"] == nil){
//we are on a long touch do nothing
return;
}
[self removeActionForKey:#"holding")];
//do tap event
}
Now this code does not handle multiple touches, you need to handle that.