ios - Easy way to reset scroll view position -


this question has answer here:

i have horizontal uicollectionview, , want reset x position. tried following:

 let indexpath = indexpath(row: 0, section: 1)   self.collectionview.scrolltoitem(at: indexpath, at: uicollectionviewscrollposition(rawvalue: 0), animated: false)

however not work, got error:

*** terminating app due uncaught exception 'nsinvalidargumentexception', reason: 'attempt scroll invalid index path: <nsindexpath: 0x61000002d040> {length = 2, path = 1 - 0}'

how scroll collection view start?

this not work if there no items 

 self.collectionview.scrolltoitem(at: indexpath, at: uicollectionviewscrollposition(rawvalue: 0), animated: false)

use (objective c):

cgpoint topoffest = cgpointmake(0,-self.collectionview.contentinset.top); [self.collectionview setcontentoffset:topoffest animated:yes];

use (swift):

let topoffest:cgpoint = cgpoint(0,-self.collectionview.contentinset.top) collectionview?.setcontentoffset(topoffest, animated: true)

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