Is there any way I can find out the rendered view in backbone? I have 4 views
Login, Contact, Home and About
I would like to find out which view currently is rendered.
Assuming you're rendering all the views into the same element (otherwise you could know what the view is from the element id), you might add a property like 'class' to the view when you create it. Then that property can be accessed through view.options.
For example:
var LoginView = Backbone.View.extend();
var loginView = new LoginView({ model: new Backbone.Model, el: 'body', class: 'login' });
loginView.render = function() { var content = 'login'; this.$el.html(content) };
loginView.render();
console.log(loginView.options.class) // 'login'
Obviously this is an oversimplified example but the general idea should work. More details or a code sample would help if you need a more specific answer.
If you also wanted to make sure the view is actually rendered, just write a method that checks if content of the view is what you expect it to be
Related
If you don't want to see the complete code, here is what I am trying to do.
I have multiple pages and each page has multiple tags. There is a composite View called PageManyView for rendering pages which called its childView PageView. Page View is a nested composite view which renders tags, passing this.model.get('tags') as collection.
Now I can easily add a new page by using pages.add(newPage). Here pages is the collection. I am facing problem in adding a new Tag. How can I do that. Please help.
CODE
var PageModel = Backbone.Model.extend({});
var PageCollection = Backbone.Collection.extend({
model: PageModel
});
My JSON at /data endpoint is coming like this
[
{
_id: '1', 'name': '1', info: 'Page 1',
tags: [{name:'main', color:'red'}, {name:'page', color:'blue'}]
},
{
_id: '1', 'name': '2', info: 'Page 2',
tags: [{name:'section', color:'blue'} {name:'about', color:'yellow'}]
}
]
I have created Nested Views in Marionette like this:
TagView = Marionette.ItemView.extend({
template: '#tagOneTemplate'
});
PageView = Marionette.CompositeView.extend({
template: '#pagesTemplate',
childViewContainer: 'div.tags',
childView: EntityViews.TagView,
initialize: function(){
var tags = this.model.get('tags');
this.collection = new Backbone.Collection(tags);
}
});
PageManyView = Marionette.CompositeView.extend({
template: '#pageManyTemplate',
childView: EntityViews.PageView,
childViewContainer: 'div#all-pages'
});
Now here is where i am facing problem. Inside Controller of my application, lets say if I have to add a new page
showPages: function(){
//Getting pages by using jQuery deferred
var view = PageMainView({collection:pages});
view.on("add:page", function(){
var newPage = Page({_id: 3});
pages.add(newPage);
});
}
Now this add function renders the new page automatically.
BUT I AM FACING PROBLEM IN ADDING a NEW TAG. HOW CAN I ADD A NEW TAG?
Finally it worked. Here is what I have done.
Step 1: Get Current model (page) from pages collection.
var currentpage = pages.get(pageid);
Step 2: Use Marionette BabySitter to get the view of the page where I want to insert a new tag.
var v = view.children.findByModel(currentpage);
Step 3: Add tag to v.collection. Since v is the View of the page where I want to insert new tag, v.collection returns the initialised tags collection
v.collection.add(tag);
This works for me. Let me know if I am wrong somewhere or a better way exists. Hope it helps.
this can be done quite easily by shifting around how your collection is being passed in. Instead of setting the collection on initialize in your compositeView, you should pass it in directly during instantiation. This way when you make a change to the collection from within your model, the compositeView will hear the "add" event on collection and add node automagically for you
For example it might look something like this.
PageView = Marionette.CompositeView.extend({
template: '#pagesTemplate',
childViewContainer: 'div.tags',
childView: EntityViews.TagView,
});
new PageView({
model: myModel,
collection: myModel.get("tags")
});
myModel.get("tags").add([{new: "object"}])
I have a very simple page that shows a collection in a table. Above it theres a search field where the user enters the first name of users.
When the user types I want to filter the list down.
Edit: I have updated the code to show how the current compositeView works. My aim is to integrate a searchView that can _.filter the collection and hopefully just update the collection table.
define([
'marionette',
'text!app/views/templates/user/list.html',
'app/collections/users',
'app/views/user/row'
],
function (Marionette, Template, Users, User) {
"use strict"
return Backbone.Marionette.CompositeView.extend({
template: Template,
itemView: User,
itemViewContainer: "tbody",
initialize: function() {
this.collection = new Users()
this.collection.fetch()
}
})
})
Divide your template in a few small templates, this increases performance at the client side, you don't have problems with overriden form elements and you have more reuseable code.
But be aware of too much separation, cause more templates means more views and more code/logic.
You don't seem to be making use of CollectionView as well as you could be. If I were you I would separate the concerns between the search box and the search results. Have them as separate views so that when one needs to rerender, it doesn't effect the other.
This code probably won't work straight away as I haven't tested it. But hopefully it gives you some clue as to what ItemView, CollectionView, and Layout are and how they can help you remove some of that boiler plate code
//one of these will be rendered out for each search result.
var SearchResult = Backbone.Marionette.ItemView.extend({
template: "#someTemplateRepresentingEachSearchResult"
)};
//This collectionview will render out a SearchResult for every model in it's collection
var SearchResultsView = Backbone.Marionette.CollectionView.extend{
itemView: SearchResult
});
//This layout will set everything up
var SearchWindow = Backbone.Marionette.Layout.extend({
template: "#someTemplateWithASearchBoxAndEmptyResultsRegionContainer",
regions:{
resultsRegion: "#resultsRegion"
},
initialize: function(){
this.foundUsers = new Users();
this.allUsers = new Users();
this.allUsers.fetch({
//snip...
});
events: {
'keyup #search-users-entry': 'onSearchUsers'
},
onSearchUsers: function(e){
var searchTerm = ($(e.currentTarget).val()).toLowerCase()
var results = this.allUsers.filter(function(user){
var firstName = user.attributes.firstname.toLowerCase();
return firstName.match(new RegExp(searchTerm))
});
this.foundUsers.set(results); //the collectionview will update with the collection
},
onRender: function(){
this.resultsRegion.show(new SearchResultsView({
collection: this.foundUsers
});
}
});
I think the most important thing for you to take note of is how CollectionView leverages the Backbone.Collection that you provide it. CollectionView will render out an itemView (of the class/type you give it) for each model that is in it's collection. If the Collection changes then the CollectionView will also change. You will notice that in the method onSearchUsers all you need to do is update that collection (using set). The CollectionView will be listening to that collection and update itself accordingly
I've been doing a bunch of reading about nested views in backbone.js and I understand a good amount of it, but one thing that is still puzzling me is this...
If my application has a shell view that contains sub-views like page navigation, a footer, etc. that don't change in the course of using the application, do I need to render the shell for every route or do I do some kind of checking in the view to see if it already exists?
It would seem so to me if someone didn't hit the "home" route before moving forward in the app.
I haven't found anything helpful about this in my googling, so any advice is appreciated.
Thanks!
Since your "shell" or "layout" view never changes, you should render it upon application startup (before triggering any routes), and render further views into the layout view.
Let's say your layout looked something like this:
<body>
<section id="layout">
<section id="header"></section>
<section id="container"></section>
<section id="footer"></section>
</section>
</body>
Your layout view might look something like this:
var LayoutView = Backbone.View.extend({
el:"#layout",
render: function() {
this.$("#header").html((this.header = new HeaderView()).render().el);
this.$("#footer").html((this.footer = new FooterView()).render().el);
return this;
},
renderChild: function(view) {
if(this.child)
this.child.remove();
this.$("#container").html((this.child = view).render().el);
}
});
You would then setup the layout upon application startup:
var layout = new LayoutView().render();
var router = new AppRouter({layout:layout});
Backbone.history.start();
And in your router code:
var AppRouter = Backbone.Router.extend({
initialize: function(options) {
this.layout = options.layout;
},
home: function() {
this.layout.renderChild(new HomeView());
},
other: function() {
this.layout.renderChild(new OtherView());
}
});
There are a number of ways to skin this particular cat, but this is the way I usually handle it. This gives you a single point of control (renderChild) for rendering your "top-level" views, and ensures the the previous element is removed before new one is rendered. This might also come in handy if you ever need to change the way views are rendered.
Apologies for the possibly poorly formulated title. New to Backbone.
I'm having trouble wrapping my head around how to deal with routes in association with views. Basically I have a view (let's call it ListView) that, depending on its viewMode, renders ItemViews using different templates. It looks something like this:
var ListView = Backbone.View.extend({
// Cache a bunch of templates here
viewMode: 'list', // Default is list
render: function() {
switch(this.viewMode) {
case 'list':
// Render ItemView based on list template
break;
case 'gallery':
// Render ItemView based on gallery template
break;
}
// Render all items in list
this.collection.each(function(model, index) {
new ItemView(); // Maybe pass viewMode as a parameter
});
}
});
My goal is that whenever ListView uses the viewMode "list" or "gallery", this should be reflected in the address bar, and likewise manually entering or clicking a link that leads to e.g. mysite.com/page.html#items/list or #items/gallery should render the same results.
Is there a way of automating this process, or in some other way solve it?
Think your router would be something like:
var yourRouter = Backbone.Router.extend({
routes: {
"items/list": "showList",
"items/gallery": "showGallery"
},
showList: function() {
listView.viewMode = "list"
listView.render();
}
showGallery: function() {
listView.viewMode = "gallery"
listView.render();
}
});
Then in your view events, you can call the navigate method of your router. This will update the address bar.
yourRouter.navigate("items/list")
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();
}