If I use limitToLast(1)
, then I still get an object, with one key-value pair. To get the value, I use this code:
db.ref('/myarray').limitToLast(1).once('value').then(function(snapshot) {
var result = snapshot.val();
var lastElem;
var lastKey;
for(var i in result) {
lastElem= result[i];
lastKey = i;
break;
}
...
});
It works, but I think I do it wrong. But haven't found any better solution in the docs. How should I load only one element?
When using Firebase queries to get children, use the "child_added"
event:
db.ref("/myarray")
.orderByKey() // order by chlidren's keys
.limitToLast(1) // only get the last child
.once("child_added", function(snapshot) {
var key = snapshot.key;
var val = snapshot.val();
...
});
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