How can I save data in forEach loop? - angularjs

Question

I create a forEach loop. I can access data from Firebase with this loop and I can change variable. But I can not save these changes on Firebase. How can I save these changes? Here's my code:
var posts = $firebaseArray(ref);
posts.$loaded().then(function(item){
item.forEach(function(childSnapshot){
var num = childSnapshot.point-1;
childSnapshot.lastPoint = num;
});
});

Answer 1

You're using the AngularFire framework, which builds UI bindings on top of Firebase's regular JavaScript SDK. You should only be using it for things that you're binding to the Angular UI elements. For everything else, you're likely better off using Firebase's regular JavaScript SDK.
If I understand your requirement correctly, you're trying to loop over all child nodes in a database location once and modify a property. If so:
ref.once('value', function(snapshot) {
snapshot.forEach(function(childSnapshot) {
var child = childSnapshot.val();
childSnapshot.ref().update({ lastPoint: child.point - 1 });
});
});
The relevant sections of the Firebase documentation are on reading data once and updating data.
Since AngularFire is built on top of Firebase's JavaScript SDK, they work perfectly together. So if elsewhere you bind the posts to the scope ($scope.posts = $firebaseArray(ref)), they will be updated automatically when you update the last point with the above snippet.

Answer 2

You can create a service that contains a getter and a setter. It would look something like this;
angular.module('app').factory("DataHandler",
function() {
var data;
return {
get: function() {
return data;
},
set: function(something) {
data = something;
}
}
}
);
Then in your code you would call:
var posts = $firebaseArray(ref);
posts.$loaded().then(function(item){
item.forEach(function(childSnapshot){
var num = childSnapshot.point-1;
childSnapshot.lastPoint = num;
DataHandler.set(childSnapshot);
});
});
Then wherever/whenever you need to get that data just call:
Datahandler.get();