I'm trying to do a tutorial backbone project with peepcode, but I got stuck.
I am trying to render a view from the console by creating a new view from a collection. Here's my code
(function($) {
window.Album = Backbone.Model.extend({
isFirstTrack: function(index) {
return index == 0;
},
isLastTrack: function(index) {
return index >= this.get('tracks').length - 1;
},
trackUrlAtIndex: function(index) {
if (this.get('tracks').length >= index) {
return this.get('tracks')[index].url;
}
return null;
}
});
window.Albums = Backbone.Collection.extend({
model: Album,
url: '/albums'
});
window.Album = Backbone.Model.extend({});
window.AlbumView = Backbone.View.extend({
tagName: 'li',
className: 'album',
initialize: function() {
_.bindAll(this, 'render');
this.model.bind('change', this.render);
this.template = _.template($('#album-template').html());
},
render: function() {
var renderedContent = this.template(this.model.toJSON());
$(this.el).html(renderedContent);
return this;
}
});
window.LibraryAlbumView = AlbumView.extend({
});
window.LibraryView = Backbone.View.extend({
tagName: 'section',
className: 'library',
initialize: function () {
_.bindAll(this, 'render');
this.template = _.template($('#library-template').html());
this.collection.bind('reset', this.render);
},
render: function() {
var $albums,
collection = this.collection;
$(this.el).html(this.template({}));
$albums = this.$(".albums");
collection.each(function(album) {
var view = new LibraryAlbumView({
model: album,
collection: collection
});
$albums.append(view.render().el);
});
return this;
}
});
})(jQuery);
When I type libraryView = new LibraryView({ collection: library })
In the console I get this response:
TypeError: Cannot call method 'replace' of null
Can anyone help me out?
Most likely the element for the library view doesn't exist in your markup.
This should be true
$('#library-template').length == 1;
This error can happen if you do:
_.template(null)
_.template(undefined);
Calling .html()
on an element that doesn't exist returns undefined
.
What exactly is the library
variable (that you're using as the value in the constructor argument to LibraryView
) set to? It's not defined globally, so it's probably null
. You'd need to first declare that variable:
var library = new Albums(),
libraryView = new LibraryView({ collection: library })
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