ios - UICollectionView: Adding item at a specified Index and scroll to this item -

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i have created vertical scrolling custom layout uicollectionview. items added collection through classic pull add , shown in alphabetical order. if add item starts z letter placed @ end of collection want collection scroll automatically show last cell.

currently i'm using code: 

 [self.collectionview performbatchupdates:^{              // update datasource             [self updatetasks];               // insert new item collection             [self.collectionview insertitemsatindexpaths:@[[nsindexpath indexpathforitem:[self.tasks indexofobject:task] insection:0]]];          } completion:^(bool finished) {              // reload data , scroll              [self.collectionview reloaddata];             [self.collectionview scrolltoitematindexpath:@[[nsindexpath indexpathforitem:[self.tasks indexofobject:task] insection:0] atscrollposition:uicollectionviewscrollpositiontop animated:yes];          }];

it works... can see use performbatchupdates add item. uicollectionview automatically animated present new cell , shift other cells. animation not shown if uicollectionview has scroll. because scrollview animating too...

in opinion best way insert item in collection view , scroll new item? i'm having hard time trying obtain beautiful , smooth animation show user new item in fashion way.

edit-------

if remove call reloaddata method scrolltoitematindexpath doesn't work... uicollectionview doesn't scroll @ all.

you not have reload data if using performbatchupdate. remove [self.collectionview reloaddata]; completion block , should works.


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