Handling Double Tap in Cocos2d - objective-c

Question

This question is too primitive, but I have been trying for the last 8 hours, and it is eating away my energy ( and confidence levels too :))
In my class, I have registered for Targeted touches.
[[CCTouchDispatcher sharedDispatcher] addTargetedDelegate:self priority:-1 swallowsTouches:YES];
I would like to check if the user is performing single tap or double tap. In ccTouchBegan method, first gets a touch with singleTap, then gets a touch with doubleTap. I found a very interesting solution for this one, in one of the Cocos2d Forums. ( I could not locate it now.. )
The solution goes like this.
switch (touch.tapCount) {
case 2:
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:#selector(handleSingleTouch:) object:singleTouchLocation];
// Handle Double Touch here
break;
case 1:
self.singleTapLocation = ccp(location.x,location.y);
self.singleTouchLocation = touch;
[self performSelector:#selector(handleSingleTouch:) withObject:touch afterDelay:0.3
];
break;
}
Everything looks to be working fine. Essentially, you schedule a single touch handler with a delay and see if it is actually a double tap. If it is a double tap, then cancel singletap handler and perform logic for double tap.
But my problem is, In the single touch handler (handleSingleTouch), I am adding a CCSprite to the UI. This action is not working. No sprite gets added. (Although the method is called.). In fact this works, If I call the selector with no delay, but with delay, the sprite is not added.
I am not a Objective C expert, So, I apologize if the question is too primitive.
Edit 1: The original thread.
Edit 2: Posting handleSingleTouch.. only relevant code.
-(void) handleSingleTouch:(UITouch * ) touch {
CGPoint location = [touch locationInView: [touch view]];
CGPoint glLocation = [MainSceneLayer locationFromTouch:touch];
//Single tap
CCLOG(#"Single tap: Adding marker image");
if(zoomedOut) {
CGPoint globalCoordinates = [quadConvertor convertLocalToGlobal:location
inActiveQuadrant:activeQuadrant];
if( [self isTouchValidForSelectedItem:globalCoordinates] == Matched) {
[self addMarkerImages:glLocation];
} else if([self isTouchValidForSelectedItem:globalCoordinates] == NotMatched) {
[missedLabel stopAllActions];
for (ImageQuadrants* quad in quadrants) {
if(quad.quadrantNumber == activeQuadrant) {
missedLabel.position = ccp((quad.center.x * -1)+glLocation.x , (quad.center.y * -1)+glLocation.y);
//markers.position = ccp((quad.center.x * -1)+touchPosition.x , 320);
}
}
id blinkAction = [CCBlink actionWithDuration:1 blinks:3];
id makeInvible = [CCCallFunc actionWithTarget:self selector:#selector(makeInvisible:)];
id seq = [CCSequence actions:blinkAction, makeInvible, nil];
[missedLabel runAction:seq];
} else {
[alreadyAccountedLabel stopAllActions];
for (ImageQuadrants* quad in quadrants) {
if(quad.quadrantNumber == activeQuadrant) {
alreadyAccountedLabel.position = ccp((quad.center.x * -1)+glLocation.x , (quad.center.y * -1)+glLocation.y);
//markers.position = ccp((quad.center.x * -1)+touchPosition.x , 320);
}
}
id blinkAction = [CCBlink actionWithDuration:1 blinks:3];
id makeInvible = [CCCallFunc actionWithTarget:self selector:#selector(makeInvisible1:)];
id seq = [CCSequence actions:blinkAction, makeInvible, nil];
[alreadyAccountedLabel runAction:seq];
}
}
swipeStartPoint = [touch locationInView:touch.view];
}

Answer 1

i dont know if thats a typo in your question only but your delay method is all wrong. There is no withDelay: argument. it should look like this:
[self performSelector:#selector(handleSingleTouch:) withObject:touch afterDelay:0.1];
EDIT:
Since your problem is most probably with the touch getting lost. Try [touch retain] before calling the delayed method. Another way is changing the handleSingleTouch: method to take two floats x and y or a CCPoint as arguments instead of a UITouch. Then you create the floats before the delayed method and pass them in the delayed method. This way you will avoid a memory leak from retaining a touch as well since most probably you cant release it after calling the delayed method.
hope this helps