angularjs - How come Angular doesn't update with scope here? -


i'm pretty new angular , i'm using firebase backend. hoping debug issue. when first go page www.mywebsite.com/#defaulthash data doesn't load dom, after visiting hash link , coming though.

my controller this:

/* initialize data */  var fb = new firebase('https://asdf.firebaseio.com/');  /* set data automatically update on change */  fb.on('value', function(snapshot) {    var data = snapshot.val();   $scope.propertyconfiguration = data.products;   console.log($scope.propertyconfiguration);   console.log("data retrieved");  });  /* save data on button submit */  $scope.saveconfigs = function(){    var setfbref = new firebase('https://asdf.firebaseio.com/products');   setfbref.update($scope.propertyconfiguration);   console.log("configurations saved!");  };

i have 3 hash routes "shared", "registration", , "home" otherwise.redirectto set "shared".(they use controller) here's error occurs: (all "links" href="#hashwhereever")

1) go website.com/#shared or refresh. console logs $scope.propertyconfiguration , "data retrieved". dom shows nothing.

2) click website.com/#registration, console logs $scope data properly, dom loaded correctly.

3) click website.com/#shared, console logs $scope data yet time dom loads correctly.

4) refresh correctly loaded website.com/#shared. dom elements disappear.

since $scope.data correct in cases here, shouldn't angular make sure dom reflects model properly? why dom loads correctly when clicking page link.

i can "fix" adding window.location.hash = "shared" throws huge amount of errors in console.

fixed:(sorta)

the function $scope.$apply() forces view sync model. i'd answer question myself , close i'm still wondering why view doesn't load correctly when correctly assign value $scope. if angular's "dirty checking" checks whenever there possibility model has changed, doesn't assigning value $scope overqualify?

angular has no way know you've assigned value $scope.variable. there's no magic here. when run directive (ng-click/ng-submit) or angular internal functions, call $apply() , trigger digest (a check of dirty flags , update routine).

a possibly safer approach $apply use $timeout. currently, if call write op in firebase, synchronously trigger event listener (child_added, child_changed, value, etc). cause call $apply while still within $apply scope. if this, error thrown. $timeout bypasses this.

see this question bit more on topic of digest , $timeout.

this doc in angular developer guide covers how compile works; great background read serious angular dev.

also, can save deal of energy using official firebase bindings angular, take of these implementation details account.

vaguely related note: in not-too-distant future, angular able take advantage of object.observe magic handle these updates.


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