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Firebase and AngularFire - $ add on array - unexpected behavior

dayPath = ref.path.toString() + '/' + configId + '/screens/' + screenIndex + '/days/',
                                // the ref for the days object
                                daysRef = fbutil.ref(dayPath),
                                // the sync for the days object
                                daysSync = fbutil.syncObjectReference(daysRef);

                            // the collection as a $firebase array
                            var list = daysSync.$asArray(),
                                items = [],
                                number;
                            console.log(list);
                            list.$add({dummy: 'Test'});

According to the documentation, when I use $ add with $ asArray, $ add should do "push". But instead, it creates a hash key instead of a numeric index.

So, bogus: test has a parent containing a hash key. The expected is a numeric index, I mean: an array element.

Can anyone help me? I just have 1 week of experience with this database.

The result is one ...

 screens
 ...0
 .......days  
 ..........0
 ..........1
 ..........2
 .........-JrT5ZATDELIR3gXAvah
 ................dummy: test
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2 answers


AngulareFire is built on the Firebase JavaScript SDK. So when the AngularFire documentation says what it uses push

internally, it's not JavaScript Array.push

, but Firebase push

operation . And Firebase push

generates its own keys, it doesn't generate regular array indices.

The reason for this is best explained in the Firebase documentation on arrays , but it essentially boils down to: Arrays don't work well in distributed environments because all clients must agree array.length

to be able to add a new item.



So, it $firebaseArray.$add

will create a so called push identifier. They are ordered like array indices, but can be generated via clients without the risk of conflicts.

I noticed that you are on an older version of AngularFire. I highly recommend that you follow the "official" AngularFire Quickstart and Guide .

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I would like to comment, but I do not have enough reputation yet, so I am doing it here.

The solution in my eyes is very simple:

Instead:



list.$add({dummy: 'Test'});

do:

list[index] = {dummy: 'Test'};
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