javascript - Pick random value from firebase snapshot -

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i'm using firebase's foreach each child in tree url

objective, when page loads grab random item firebase , show it

data structure

 grabbit (table name)        active (for active items sale)            category (the category of item ie womensclothes, mensshoes etc)                   unique id of item

on page load go http://gamerholic.firebase.com/grabbit/active , grab 1 of categories , return it..

script

var grabbitref = new firebase('https://gamerholic.firebaseio.com/grabbit/active/'); grabbitref.on('value', function(snapshot) { if(snapshot.val() === null) { alert("invalid"); } else {   // snap shot data:  snapshot.foreach(function(snapshot) {   var name = snapshot.name(); alert(name); });  } });

after have random category "electronics", new snapshot , have return random item that's in electronics

 var grabbitref = new firebase('https://gamerholic.firebaseio.com/grabbit/active/'+name); grabbitref.on('value', function(snapshot) { if(snapshot.val() === null) { alert("invalid"); } else {   // snap shot data:  snapshot.foreach(function(snapshot) {   var id = snapshot.name(); alert(id); });  } });

with id can details of item

var grabbitref = new firebase('https://gamerholic.firebaseio.com/grabbit/active/'+name+'/'+id);

it's not possible grab random item list in firebase, unfortunately. can limit(1) grab first item, or endat().limit(1) grab last item.

if you're using foreach, can grab items , picking 1 @ random, using math.random. example:

var = 0; var rand = math.floor(math.random() * snapshot.numchildren()); snapshot.foreach(function(snapshot) {   if (i == rand) {     // picked random item, snapshot.val().   }   i++; });

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