Multiple delete using Backbone.js - backbone.js

I have Controller method which accepts List for multiple delete
[HttpPost]
public void DeleteAsync(List<int> ids)
{
}
How do I call this method from Backbone? can I have something like below?
var someView = backbone.View.extend({
el: '',
selectedArray: [],
render: function () {},
multipleDelete: function () {
// here i want to do something like below
selectedArray.destroy("/MyController/Delete");
//or somthing like
var someCollection=Backbone.Collection.extend();
//Adding the selectedArray values to someCollection and calling destroy
//configuring the URL
}
});

By default Backbone expects a RESTful API, so when you call MyCollection.remove(models) it will tigger DELETE /myapp/MyModel as many times as models you pass in the parameters. If you want to make a batch delete operation, you need to make some extra work creating your own AJAX call, to the endpoint you want with the list of IDs you want to delete.

Related

Why backbone add extra parameter to url path?

I am using backbone.marionette (1.0.0) and node.js (0.10.22). Wondering why backbone add extra parameter when I try to save model data with node.js REST call.
model.js
Backbone.Model.extend ({
urlRoot: function (){
return '/path/' + myApp.companyId;
},
defaults: {
companyId: '',
// other attributes
},
// doesn't use 'id' in model instead companyId
idAttribute: 'companyId'
});
Before view is loaded, I would request model data with myApp.request ('entities:myModel') which issued model.fetch () and node.js backend would fire GET /path/1 route. No issue.
However, when an update button is clicked on the view, this.model.save () would fired PUT /path/1/1. It should be PUT /path/1, with only a single '1' in url path.
view.js:
clicked: function () {
var formData = Backbone.syphon.serialize (this);
this.model.set (formData);
var promise = this.model.save ();
promise.done ().fail ()
}
How can I stop backbone.sync from appending extra parameter to url path? Thanks for taking time out to read this, and I appreciate your help.
You're setting urlRoot incorrectly on the model. It should be
Backbone.Model.extend ({
urlRoot: "path",
// etc
});
Backbone willa dd the ids on it's own.
If you want to specify the ids in your function, use the url function.

How can I populate the backbone model if I overrode 'fetch'?

I'm building some JS to access Google places JS API using backbone. So far I'm really stuck with the model bindings.
I overrode 'fetch' to be able to use the Google API. The call to Google works just fine.
var Places = Backbone.Collection.extend({
model: Place,
fetch: function(options) {
// SNIPPET //
service = new google.maps.places.PlacesService(map);
service.nearbySearch(request, this.googlePlaceCallback);
// SNIPPET //
},
parse: function(response){
// nerver called
},
googlePlaceCallback: function(results, status) {
// I do something here and is properly called after Google returns a response
}
});
I also defined a very simple View:
var MapView = Backbone.View.extend({
initialize: function() {
this.model = new Places();
this.model.bind("reset", this.render, this);
this.model.fetch();
},
render : function () {
console.log( this.model.toJSON() );
}
});
I can't figure out how to populate the 'model'. Google returns the expected results, but I can set them to the backbone model. I there something I need to do in 'googlePlaceCallback'? I'll probably will need to override 'parse' also since Google results are not quite all interesting.
Assuming that results is a collection of the results you want, you should be able to implement the callback as follows:
googlePlaceCallback: function(results, status) {
this.add(results);
}
Since Places is a backbone Collection, you're just calling the following method in the above code: http://backbonejs.org/#Collection-add
You will also have to get the correct this reference inside the googlePlaceCallback function (you want this to be the Collection). One way to do that is to use Underscores bindAll method ( http://underscorejs.org/#bindAll ), which you can use to make sure all methods in the Backbone class have a this context of the Collection itself. You can do this on initialize as follows:
initialize: function() {
_.bindAll(this);
}
Also, the reason parse is not being called is because you are overriding fetch, and fetch calls parse. If you take a look at the annotated backbone code, you will be able to see the method call: http://backbonejs.org/docs/backbone.html

Backbone.js: just one line to set local storage?

demo fiddle (with problem) http://jsfiddle.net/mjmitche/UJ4HN/19/
I have a collection defined like this
var Friends = Backbone.Collection.extend({
model: Friend,
localStorage: new Backbone.LocalStorage("friends-list")
});
As far as I'm aware, that's all I need to do to get local storage to work (in addition to including it below backbone.js)
One thing I wasn't sure about, does the name "friends-list" have to correspond to a DOM element? I'm trying to save the "friends-list" so I called it that in local storage, however, localstorage doesn't seem to require passing a class or an id.
Here's a fiddle where you can see what I'm trying to do http://jsfiddle.net/mjmitche/UJ4HN/19/
On my local site, I'm adding a couple friends, refreshing the page, but the friends are not re-appearing.
Update
I've also done the following in my code on my local site
console.log(Backbone.LocalStorage);
and it's not throwing an error.
My attempt to debug
I tried this code (taken from another SO answer) in the window.AppView but nothing came up in the console.
this.collection.fetch({}, {
success: function (model, response) {
console.log("success");
},
error: function (model, response) {
console.log("error");
}
})
From the fine manual:
Quite simply a localStorage adapter for Backbone. It's a drop-in replacement for Backbone.Sync() to handle saving to a localStorage database.
This LocalStorage plugin is just a replacement for Backbone.Sync so you still have to save your models and fetch your collections.
Since you're not saving anything, you never put anything into your LocalStorage database. You need to save your models:
showPrompt: function() {
var friend_name = prompt("Who is your friend?");
var friend_model = new Friend({
name: friend_name
});
//Add a new friend model to our friend collection
this.collection.add(friend_model);
friend_model.save(); // <------------- This is sort of important.
},
You might want to use the success and error callbacks on that friend_model.save() too.
Since you're not fetching anything, you don't initialize your collection with whatever is in your LocalStorage database. You need to call fetch on your collection and you probably want to bind render to its "reset" event:
initialize: function() {
_.bindAll(this, 'render', 'showPrompt');
this.collection = new Friends();
this.collection.bind('add', this.render);
this.collection.bind('reset', this.render);
this.collection.fetch();
},
You'll also need to update your render to be able to render the whole collection:
render: function() {
var $list = this.$('#friends-list');
$list.empty();
this.collection.each(function(m) {
var newFriend = new FriendView({ model: m });
$list.append(newFriend.render().el);
});
$list.sortable();
return this;
}
You could make this better by moving the "add one model's view" logic to a separate method and bind that method to the collection's "add" event.
And a stripped down and fixed up version of your fiddle: http://jsfiddle.net/ambiguous/haE9K/

Query Database with Backbone Collection

I need to query the database using a backbone collection. I have no idea how to do this. I assume that I need to set a url somewhere, but I don't know where that is. I apologize that this must be a very basic question, but I took a backbone course on CodeSchool.com and I still don't know where to begin.
This is the code that I have for the collection:
var NewCollection = Backbone.Collection.extend({
//INITIALIZE
initialize: function(){
_.bindAll(this);
// Bind global events
global_event_hub.bind('refresh_collection', this.on_request_refresh_collection);
}
// On refresh collection event
on_request_refresh_collection: function(query_args){
// This is where I am lost. I do not know how to take the "query_args"
// and use them to query the server and refresh the collection <------
}
})
The simple answer is you would define a URL property or function to your Backbone.Collection like so:
initialize: function() {
// Code
},
on_request_refresh_collection: function() {
// Code
},
url: 'myURL/whateverItIs'
OR
url: function() {
return 'moreComplex/' + whateverID + '/orWhatever/' + youWant;
}
After your URL function is defined all you would have to do is run a fetch() on that collection instance and it will use whatever you set your URL to.
EDIT ------- Making Collection Queries
So once you set the URL you can easily make queries using the native fetch() method.
fetch() takes an option called data:{} where you can send to the server your query arguments like so:
userCollection.fetch({
data: {
queryTerms: arrayOfTerms[], // Or whatever you want to send
page: userCollection.page, // Pagination data
length: userCollection.length // How many per page data
// The above are all just examples. You can make up your own data.properties
},
success: function() {
},
error: function() {
}
});
Then on your sever end you'd just want to make sure to get the parameters of your request and voila.

Can't get iscroll4 to play with backbone view

I am trying to use iScroll4 inside a backbone.js application. I have several dynamically loaded lists, and I want to initialize iScroll after the appropriate view has loaded.
I'm trying to call 'new iScroll' when the list view finishes loading, but cannot for the life of me figure out how to do this.
Has anyone gotten these two to work together? Is there an example out there of a backbone view initializing a scroller once its element has loaded?
you are correct, you have to load the view first,
or defenately refresh iscroll afterwards
in our applications, we usually use the render method to render the view
and have a postRender method that handles initialization of these extra plugins like iscroll
of course you need some manual work to get it done but this is the gist of it:
var myView = Backbone.View.extend({
// more functions go here, like initialize and stuff... but I left them out because only render & postRender are important for this topic
// lets say we have a render method like this:
render: function() {
var data = this.collection.toJSON();
this.$el.html(Handlebars.templates['spotlightCarousel.tmpl'](data));
return this;
},
// we added the postRender ourself:
postRender: function() {
var noOfSlides = this.collection.size();
$('#carouselscroller').width(noOfSlides * 320);
this.scroller = new IScroll('carouselwrapper', {
snap: true,
momentum: false,
hScrollbar: false
});
}
});
now the calling of these methods
we did this outside our view as we like some view manager to handle this
but it boils down to this
var col = new myCollection();
var view = new myView({ collection: col });
$('#wrapper').html(view.render().$el); // this chaining is only possible due to the render function returning the whole view again.
// here we always test if the view has a postRender function... if so, we call it
if (view.postRender) {
view.postRender();
}

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