Swift iOS: Firebase Paging -


i have firebase data:

firebase data

i want query posts data through pagination. code converting js code swift code

let postsref = self.rootdatabasereference.child("development/posts") postsref.queryorderedbychild("createdat").querystartingatvalue((page - 1) * count).querylimitedtofirst(uint(count)).observesingleeventoftype(.value, withblock: { snapshot in ....    })

when accessing, data page: 1, count: 1. can data "posts.a" when try access page: 2, count: 1 returns still "posts.a"

what missing here?

assuming or using childbyautoid() when pushing data firebase, can use queryorderedbykey() order data chronologically. doc here.

the unique key based on timestamp, list items automatically ordered chronologically.

to start on specific key, have append query querystartingatvalue(_:).

sample usage:

var count = numberofitemsperpage  var query ref.queryorderedbykey()  if startkey != nil {   query = query.querystartingatvalue(startkey)   count += 1 }  query.querylimitedtofirst(uint(count)).observesingleeventoftype(.value, withblock: { snapshot in   guard var children = snapshot.children.allobjects as? [firdatasnapshot] else {     // handle error     return   }    if startkey != nil && !children.isempty {     children.removefirst()   }    // children })

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