• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
how to correctly implement intertial scrolling using -scrollWheel: ?
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

how to correctly implement intertial scrolling using -scrollWheel: ?


  • Subject: how to correctly implement intertial scrolling using -scrollWheel: ?
  • From: Nicolas Ojeda Bar <email@hidden>
  • Date: Thu, 14 Jul 2016 07:59:48 +0200

Hi list,

I am implementing a custom NSView which displays pdf files and the
like.  I am not/can not use
NSScrollView.

I would like to implement intertial scrolling (when using trackpad)
like in Preview or Safari.

So far I am receiving scrollWheel events on the NSView and doing something like:

- (void)scrollWheel:(NSEvent *)event
{
  CGFloat deltaY = -[event scrollingDeltaY];

  if ([event hasPreciseScrollingDeltas]) {
    if (fabs (deltaY) > 0) {
      [connector scrollBy:deltaY]; // performs scrolling of deltaY points
  }
}

This works to a first approximation.  However the intertial scrolling
seems to be quite "laggy" when
2-finger swiping at *slow* speeds.  Also, when changing direction of
scrolling/swiping quickly the
scrolling in one direction continues for a bit before changing direction.

In Preview when one changes the direction of scrolling this occurs
immediately without any lag.

Does anybody have any ideas of where I should be looking to fix this ?
 Any suggestion appreciated.

Thanks!

Cheers,
Nicolas
_______________________________________________

Cocoa-dev mailing list (email@hidden)

Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:

This email sent to email@hidden


  • Prev by Date: gesture-based and interruptible animations
  • Next by Date: Re: specifying UIInterfaceOrientationMask
  • Previous by thread: gesture-based and interruptible animations
  • Next by thread: Root URL and URLByDeletingLastPathComponent
  • Index(es):
    • Date
    • Thread