This is my first day of learning backbone. I have been going through some tutorials to get a better grasp. I keep getting the same error
Cannot read property 'localStorage' of undefined
I have come across this with a couple of tutorials I've tried.
I made sure to load backbone local storage last.
This error keeps happening when I try to do a fetch in backbone.
For now my code is very short
var Beer = Backbone.Model.extend();
var BeerList = Backbone.Collection.extend({
model: Beer
});
var BeerList = Backbone.Collection.extend({
model: Beer,
url: 'http://beer.fluentcloud.com/v1/beer'
});
var beers = new BeerList();
beers.fetch();
beers.bind('reset',function() {
console.log(beers);
}).
I have also tried to change the url to a json file, but I keep getting the same problem. I am wondering how to debug this issue?
Related
I am building an app for a client who has, as one of their data sets a master list of all their members. I have the data coming in from Firebase and everything runs peachy, but it's not that DRY I am now realizing. I would like to use some of the data from the membership set in other views within the site. I copied the code listed below into other controllers that I need to have access to it and although everything works, my IDE (RubyMine) shows the 'syncObject' as redundant.
So, my question is, if there's a way to code it better and dryer to be used in other views? Thank you for your time.
.controller( 'MembershipCtrl', function MembershipCtrl( $scope, $firebase ) {
var ref = new Firebase("https://myid.firebaseio.com/members");
var sync = $firebase(ref);
var syncObject = sync.$asArray();
$scope.members = syncObject;
});
I have been through several tutorials and posts about this topic and still can't seem to figure out what is wrong with my code. To me it seems I am having scoping issues with the data within my service. My code is split up into separate files. Here is my code:
github link : https://github.com/StudentJoeyJMStudios/PetPinterest.git
//in dataService.js
var app = angular.module('se165PetPinterestWebApp');
app.service('SharedData', function ()
{
var categoryOfSelectedAnimals = [];
this.setCatOfSelAnimals = function(pulledCategoriesFromParse)
{
categoryOfSelectedAnimals = pulledCategoriesFromParse;
console.log('after assignment in set::' + categoryOfSelectedAnimals);
};
this.getCatOfSelAnimals = function()
{
console.log('in get::::' + categoryOfSelectedAnimals);
return categoryOfSelectedAnimals;
};
});
in my first controller to set the data in signup.js
app.controller('SignupCtrl',['$scope', 'SharedData', function ($scope, SharedData)
{
var Categories = Parse.Object.extend('Categories');
var query = new Parse.Query(Categories);
query.find({
success: function(results)
{
$scope.availableCategoriesOfAnimals = results;
SharedData.setCatOfSelAnimals(results);
},
error: function(error)
{
alert('Error: ' + error.code + ' ' + error.message);
}
});
};
}]);
Then in my other controller trying to get the data from the array within my service:
var app = angular.module('se165PetPinterestWebApp');
app.controller('CatSelCtrl', function ($scope, SharedData)
{
$scope.availableCategoriesOfAnimals = SharedData.getCatOfSelAnimals();
});
When I print the contents from the SharedData.getCatOfSelAnimals I get 0 every time. Please help. Thank you very much in advance.
EDIT: After playing around with a string a bit I am finding the changed string in the set function is not saved into the service and when I call my get function within my service the string is not changed from the set method. Please help, thank you in advance.
EDIT: So it looks like when I navigate to new page by using window.location.href = '../views/categorySelection.html'; in my signup.js it reloads my dataService.js which re-sets my variables back to nothing. Does anyone have any ideas as to how to fix this?
Edit
First: why you lose data
You need to setup routing properly. Right now you are not changing views but rather using window.location.href to load a new bootstrap file (dashboard.html), i.e. everything saved in memory will be lost. So you have been doing it right, sort of, but the moment you change to dashboard.html all data from Parse is lost.
You can solve this by configuring routes and use $location.url() to change URL. Read more about angular.route here: https://docs.angularjs.org/api/ngRoute/service/$route
The angular way
After looking at your code and running your app I think we need to take a step back. Angular is tricky to get used to but there is a lot of good tutorials. I think you might wanna read some of them to get a better grasp of how it works and how to setup and build your app.
Start here: http://www.airpair.com/angularjs
Boilerplate
Found this boilerplate for an Angular app using Parse. It might be something you could use. https://github.com/brandid/parse-angular-demo
Original
Or an even quicker way to empty $scope.availableCategoriesOfAnimals and then merge new data without breaking reference:
$scope.availableCategoriesOfAnimals.length = 0;
Array.prototype.push.apply($scope.availableCategoriesOfAnimals, pulledCategoriesFromParse);
You are breaking the reference on assignment. This is a JavaScript issue, not an angular one for that matter ;)
Try this in your set function:
categoryOfSelectedAnimals.length=0;
pulledCategoriesFromParse.forEach(function (e) {categoryOfSelectedAnimals.push(e)});
in stead of reassigning
edit: angular extend works on objects, not arrays, so replaced it with a bit of JS.
First time posting here... looking forward to see how it all works, but have really appreciated reading other's questions & answers.
I am using backbone for a small app and have found it helpful to use a collection to store some information that is only required during the current session. (I have a number of collections and all the others connect to my API to store/retrieve data).
I read here (in backbone.js can a Model be without any url?) that it is possible, and even good to use a collection without providing a url.
Now I would like to add a row of data to the collection... simple:
myCollection.create(data);
but of course that now throws an error:
Uncaught Error: A "url" property or function must be specified
Is there any way to use a Backbone collection, be able to add new rows of data (models) to it, but not sync to any sort of data source. Or can you suggest another solution.
I guess I could just use an object to hold the data, but I was enjoying the consistency and functionality.
I am using Backbone.Marionette if that has any impact.
Thanks in advance.
One thing you could do is override the Backbone.Model methods that communicate with the server, i.e. sync, fetch, and save... for example:
var App = {
Models: {},
Collections: {}
};
App.Models.NoUrlModel = Backbone.Model.extend({});
App.Models.NoUrlModel.prototype.sync = function() { return null; };
App.Models.NoUrlModel.prototype.fetch = function() { return null; };
App.Models.NoUrlModel.prototype.save = function() { return null; };
App.Collections.NoUrlModels = Backbone.Collection.extend({
model: App.Models.NoUrlModel,
initialize: function(){}
});
var noUrlModels = new App.Collections.NoUrlModels();
noUrlModels.create({'foo': 'bar'}); // no error
// noUrlModels.models[0].attributes == {'foo': 'bar'};
See Demo
The problem
I want to have a default error handler in my app that handles all unexpected errors but some time (for example when saving a model) there are many errors that can be expected so I want to handle them in a custom way rather than show a generic error page.
My previous solution
My Backbone.sync function used to have this:
if(options.error)
options.error(response)
else
app.vent.trigger('api:error', response) # This is the global event channel
However, this no longer works since backbone always wraps the error function so it can trigger the error event on models.
New solution 1
I could overwrite the fetch and save methods on models and collections to wrap options.error and have the code above there but this feels kinda ugly.
New solution 2
Listen to error on models, this won't allow me to override the default error handler though.
New solution 3
Pass in a custom option to disable the global triggering of the errors, this feels redundant though.
Have I missed anything? Is there a recommended way of doing this?
I can add that I'm using the latest version from their git repo, not the latest from their home page.
Could you do this in your overridden sync? This seems to accomplish the same thing you did before.
// error is the error callback you passed to fetch, save, etc.
var error = options.error;
options.error = function(xhr) {
if (error) error(model, xhr, options);
// added line below.
// no error callback passed into sync.
else app.vent.trigger('api:error', xhr);
model.trigger('error', model, xhr, options);
};
This code is from Backbone source, I only add the else line.
EDIT:
This is not the prettiest solution, but might work for you. Create a new Model base class to use, instead of extending Backbone.Model, extend this.
var Model = Backbone.Model.extend({
// override fetch. Do something similar for save, destroy.
fetch: function(options){
options = options ? _.clone(options) : {};
var error = options.error;
options.error = function(model, resp) {
if (error) error(model, resp);
else app.vent.trigger('api:error', resp);
};
return Backbone.Model.prototype.fetch.apply(this, [options]);
},
});
var MyModel = Model.extend({});
var model = new MyModel();
model.fetch(); // error will trigger 'api:error'
Actually, this might be better than overriding sync anyways.
Possible alternative is to use this: http://api.jquery.com/ajaxError/.
But with that, you will get the error regardless of whether you passed in an error callback to backbone fetch/save/destroy.
I'm trying to get the backbone.js DELETE request to fire, but don't see any requests being made in my console.
I have collection model like so:
var Model = Backbone.Model.extend(
{
urlRoot: '/test',
defaults:{}
});
var TableList = Backbone.Collection.extend(
{
url: '/test',
model: Model
});
In my view I'm running this:
this.model.destroy();
Everything seems to be running fine, I can see output coming from the remove function that calls the destroy so I know it's getting there plus it also successfully runs an unrender method that I have. Can't see any requests being made to the sever though?
If I am not mistaken, you have to have an id property on your model to ensure that it hits the correct url. IE if your model was...
var Model = Backbone.Model.extend({
url: '/some/url'
});
var model = new Model({
id: 1
});
model.destroy(); // I THINK it will now try and DELETE to /some/url/1
Without an id it doesn't know how to build the url correctly, typically you'd fetch the model, or create a new one and save it, then you'd have a Url...
See if that helps!
I found the issue to my problem, thought not a solution yet. I'm not sure this is a bug with backbone or not, but I'm using ajaxSetup and ajaxPrefilter. I tried commenting it out and it worked. I narrowed it down to the ajaxSetup method and the specifically the use of the data parameter to preset some values.
Have you tried using success and error callbacks?
this.model.destroy({
success : _.bind(function(model, response) {
...some code
}, this),
error : _.bind(function(model, response) {
...some code
}, this);
});
Might be instructive if you're not seeing a DELETE request.