Sparrow Forum

1. 

   saumya
   Member

   just thinking my events are being fired 2 times !!
   Upon user tap, I am validating the answer and dispatching a custom event, but not sure why these tap events fire up 2 times. Or there is some parameter I am missing to set it up.

   Posted 1 year ago #
2. 

   alex_h
   Moderator

   You might be accidentally responding to both TouchesBegan and TouchesEnded. Make sure you included a check on the SPTouch object to ensure you only respond to the desired type.

   cheers,
   Alex

   Posted 1 year ago #
3. 

   saumya
   Member

   Hey thanks Alex,
   my code just does this,
   [self addEventListener:@selector(onOptionSelect:) atObject:self forType:SP_EVENT_TYPE_TOUCH];

   I waas going through the docs, but could not get where to check the TouchesBegan and TouchesEnded events. A sample code will help a lot.

   saumya

   Posted 1 year ago #
4. 

   alex_h
   Moderator

   There are some useful examples here:
   http://www.sparrow-framework.org/help/documentation/#events

   including one on how to check the event phase from within your event handler using SPTouchEvent touchesWithTarget: andPhase:

   Here's an example that checks for the event phase 'touches began'

   - (void)onTouch:(SPTouchEvent*)event
    {
        SPTouch *touch = [[event touchesWithTarget:self andPhase:SPTouchPhaseBegan] anyObject];
        if (touch)
        {
            SPPoint *touchPosition = [touch locationInSpace:self];
            NSLog(@"Touched position (%f, %f)", touchPosition.x, touchPosition.y);
        }
    }

   Posted 1 year ago #
5. 

   saumya
   Member

   oops!
   Sorry for my panic. I got it Alex, thank you so very much.
   Th trick is in the handler and yes, there is doc in the Sparrow documentation regarding that.

   NSArray *touches = [[event touchesWithTarget:self andPhase:SPTouchPhaseBegan] allObjects];
   if (touches.count==1) {
   NSLog(@"One fingure touching!-------");
   }

   Cheers,
   saumya

   Posted 1 year ago #
6. 

   saumya
   Member

   it works but I do not get the last parameter, anyObject/allObjects ?
   whats the difference?

   Posted 1 year ago #
7. 

   alex_h
   Moderator

   touchesWithTarget returns an NSSet which is a group of objects, in order to support multitouch. so anyObject is a method of NSSet that returns 'anyObject' from the set (ie a single object, in this case an SPTouch instance).
   allObjects is another method ofNSSet that returns an array containing all the objects in the set. Unless you are building a multitouch feature I would expect that you could normally just use the 'anyObject' method.

   Alex

   Posted 1 year ago #
8. 

   saumya
   Member

   Thank you Alex. Can not say more
   chees

   Posted 1 year ago #

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