It's an easy example as following:
There are many avatars and only one avatar can be selected each time.
I have a model 'Avatar', collection 'Avatars' and model's view 'AvatarView'.
Also there is a view named 'AvatarAppView' which is responsible to render the app view.
My implementation is as following:
When one avatar is selected, click event is trigged in the model's view 'AvatarView', then it will be selected but cannot make other models unselected.
Are there any nice solutions? Thank you.
Backbone views have Backbone.Events mixed in so views can produce their own events and other views can listen for those events. So your AvatarView can trigger an event when it is selected:
select: function() {
// Mark this avatar as selected...
this.trigger('selected', this);
},
unselect: function() {
// Undo the "mark this avatar as selected" from above.
}
and then the AvatarAppView can listen for those events:
initialize: function() {
_.bindAll(this, 'selected');
//...
},
render: function() {
this.kids = [ ];
this.collection.each(function(m) {
var v = new AvatarView({ model: m });
v.on('selected', this.selected);
this.kids.push(v);
this.$el.append(v.render().el);
}, this);
return this;
}
Then a simple selected event handler for AvatarAppView to unselect the other AvatarViews:
selected: function(v) {
_.chain(this.kids).reject(function(k) { return k == v }).invoke('unselect');
}
Demo: http://jsfiddle.net/ambiguous/thRHK/
Related
I have a view that contains two sub views, each with their own HTML template.
It works fine for what I have now. However, I now need an event to be fired from one subview to the other.
For example, when the user is in the Edit View, and they forget to click something(checkbox, radio button, or whatever), and they go back to the Display View, I want a warning to show up in that display view template(html) that warns them of the things they missed.
Is this possible? To pass events around like this between sibling views?
Thanks!
Here's the basic code structure I have now:
return Backbone.View.extend({
render: function(SubView) {
SubView = SubView || DisplayView;
this.view = new SubView({
model: this.model
});
this.$el.html(this.view.render().$el);
return this;
}
})
var DisplayView = Backbone.View.extend({
render: function() {
this.$el.html(this.template(this.model.toJSON()));
})
var EditView = Backbone.View.extend ({
toggleDisplay: function () {
this.checkAllItems();
},
checkAllItems: function() {
if (this.$('.engineParts').val().length > 0) {
this.render(DisplayView);
} else {
this.$('.awarning').css('display', 'block'); //warning class in DisplayView template.
this.render(DisplayView);
}
}
})
I'm having trouble figuring out how to quickly, and simply attach a listener for events triggered on a Backbone.Marionette view.
I can currently accomplish what I'm looking for by adding a listener via .on, but is there a quick way via the events or triggers hashes? Something like this seems like it should work but doesn't:
return Marionette.ItemView.extend({
triggers: {
"click .close": "menu:close"
},
events: {
"menu:close #": "close",
},
close: {
// do stuff
}
}
Update
There is actually a (simple) way to do exactly what you want.
// Itemview
var itemView = Marionette.ItemView.extend({
initialize: function() {
Marionette.bindEntityEvents(this, this, this.events);
},
template: "#item",
triggers: {
"click .btn": "menu:performAction"
},
events: {
"menu:performAction": "performAction"
},
performAction: function() {
console.log('test');
}
});
In short this binds your events attribute containing the hashes to the views events.
Fiddle: http://jsfiddle.net/8T68P/
Documentation: https://github.com/marionettejs/backbone.marionette/blob/master/docs/marionette.functions.md#marionettebindentityevents
Old answer
See this fiddle: http://jsfiddle.net/Cardiff/K5TTQ/
Listening to events like that won't work indeed. And if you happen to use the .on method from within your view. Please use listenTo. That will be cleaned up properly when the view is closed. Like this:
// Itemview
var itemView = Marionette.ItemView.extend({
initialize: function() {
var view = this;
view.listenTo(view, "menu:performAction", view.performActionFromListenTo);
},
template: "#item",
triggers: {
"click .btn": "menu:performAction"
},
performActionFromListenTo: function() {
console.log('test');
}
});
I'm semi-new to backbone. I'm trying to bind a collection to a view so that when a new model is added to a collection, the view is updated. I think when you do this with models you can bind to the model's change event. But how do you do the same with collections?
App.Views.Hotels = Backbone.View.extend({
tagName: 'ul',
render: function() {
this.collection.each(this.addOne, this);
var floorplanView = new App.Views.Floorplans({collection:floorplanCollection});
$('.floorplans').html(floorplanView.render().el);
return this;
},
events: {'click': 'addfloorplan'},
addOne: function(hotel) {
var hotelView = new App.Views.Hotel ({model:hotel});
this.$el.append(hotelView.render().el);
},
addfloorplan: function() {
floorplanCollection.add({"name": "another floorplan"});
}
});
App.Collections.Floorplans = Backbone.Collection.extend({
model: App.Models.Floorplan,
initialize: function () {
this.bind( "add", function() {console.log("added");} );
}
});
The click event fires and adds to the collection. But how do I get it to update the view?
You can listen to the collection's add event, which fires when a new item is added to the collection. In modern versions of Backbone, the method listenTo is preferred to bind or on for listening to events. (Read de documentation for more info)
For example, in your case this should do the trick:
App.Views.Hotels = Backbone.View.extend({
initialize: function() {
this.listenTo(this.collection,'add', this.addOne);
},
//rest of code
Hope this helps!
Here is a nice tutorial I had followed long ago.
An Intro to Backbone.js: Part 3 – Binding a Collection to a View
It helps you define a DonutCollectionView that will, when given a collection of donuts, render an UpdatingDonutView for each donut.
I have a two views:
1 LeftView (maximized when RightView is minimized & vice versa)
2 RightView (containing)
- collection of
- RightItemView (rendering RightItemModel)
When RightView is maximized and the user clicks a RightItemView, I want to maximize LeftView and display something according to the data from the clicked RightItemView.
What's the proper way to wire them?
I would recommend using the Backbone.Events module:
http://backbonejs.org/#Events
Basically, this line is all it takes to create your event dispatcher:
var dispatcher = _.clone(Backbone.Events);
Then all of your views can trigger/listen for events using the global dispatcher.
So, in RightItemView you would do something like this in the click event:
dispatcher.trigger('rightItemClick', data); // data is whatever you need the LeftView to know
Then, in LeftView's initialize function, you can listen for the event and call your relevant function:
dispatcher.on('rightItemClick', this.maximizeAndDisplayData);
Assuming your LeftView would have a function like so:
maximizeAndDisplayData: function(data) {
// do whatever you need to here
// data is what you passed with the event
}
The solution #jordanj77 mentioned is definitely one of the correct ways to achieve your requirement. Just out of curiosity, I thought of another way to achieve the same effect. Instead of using a separate EventDispatcher to communicate between the two views, why shouldn't we use the underlying model as our EventDispatcher? Let's try to think in those lines.
To start with, add a new boolean attribute to the RightItem model called current and default it to false. Whenever, the user selects the RightItemView, set the model's current attribute to true. This will trigger a change:current event on the model.
var RightItem = Backbone.Model.extend({
defaults: {
current: false,
}
});
var RightItemView = Backbone.View.extend({
events: {
'click li': 'changeCurrent'
}
changeCurrent: function() {
this.model.set('current', true);
}
});
On the other side, the LeftView will be handed a Backbone.Collection of RightItem models during creation time. You would anyways have this instance to supply the RightView isn't it? In its initialize method, the LeftView will listen for change:current event. When the event occurs, LeftView will change the current attribute of the model it is currently displaying to false and start displaying the new model that triggered this event.
var LeftView = Backbone.View.extend({
initialize: function() {
this.collection.on('change:current', this.render, this);
},
render: function(model) {
// Avoid events triggered when resetting model to false
if(model.get('current') === true) {
// Reset the currently displayed model
if (this.model) {
this.model.set('current') = false;
}
// Set the currently selected model to the view
this.model = model;
// Display the view for the current model
}
}
});
var leftView = new LeftView({
// Use the collection that you may have given the RightView anyways
collection: rightItemCollection
});
This way, we get to use the underlying model as the means of communication between the Left and Right Views instead of using an EventDispatcher to broker for us.
The solution given by #Ganeshji inspired me to make a live example
I've created 2 views for this.
var RightView = Backbone.View.extend({
el: $('.right_view'),
template: _.template('<p>Right View</p>'),
renderTemplate: function () {
this.$el.html('');
this.$el.append(this.template());
this.$link = this.$el.append('Item to view').children('#left_view_max');
},
events: {
'click #left_view_max' : 'maxLeftView'
},
maxLeftView: function () {
//triggering the event for the leftView
lView.trigger('displayDataInLeftView', this.$link.attr('title'));
},
initialize: function (options) {
this.renderTemplate();
}
});
var LeftView = Backbone.View.extend({
el: $('.left_view'),
template: _.template('<p>Left View</p>'),
renderTemplate: function () {
this.$el.html('');
this.$el.append(this.template());
},
displayDataInLeftView: function (data) {
this.$el.append('<p>' + data + '</p>');
},
initialize: function (options) {
//set the trigger callback
this.on('displayDataInLeftView', this.displayDataInLeftView, this);
this.renderTemplate();
}
});
var lView = new LeftView();
var rView = new RightView();
Hope this helps.
So I have a View that looks like this.
//base class
var SelectListView = Backbone.View.extend({
initialize: function() {
_.bindAll(this, 'addOne', 'addAll');
this.collection.bind('reset', this.addAll);
},
addAll: function() {
this.collection.each(this.addOne);
},
events: {
"change": "changedSelected"
},
changedSelected: function() {
this.selected = $(this.el);
this.setSelectedId($(this.el).val());
}
});
//my extended view
var PricingSelectListView = SelectListView.extend({
addOne: function(item) {
$(this.el).append(new PricingView({ model: item }).render().el);
}
});
I have instantiated the view like this...
var products = new ProductPricings();
var pricingsView = new PricingSelectListView({
el: $("#sel-product"),
collection: products
});
Somewhere else (another views custom method)I have updated the pricing view's collection
pricingsView.collection = new ProductPricings(filtered);
This does not seen to do anything.
pricingsView.render();
So now the collection has fewer items but the new view is never rendered or refreshed in the DOM.
How to I do I 1.) refresh the rendering in the DOM? 2.) Make it automatically refresh the DOM? Do I have to somehow tell it to render when ever the collection changes?
You bound addOne() to a reset event. When you just replace the pricingsView.collection instance then that event is not triggered and addOne() is not executed.
Try instead:
pricingsView.collection.reset(filtered);
This might work since you bind to collection's reset event already:
pricingsView.collection.reset(filtered);
http://backbonejs.org/#Collection-reset
You still have tweak your rendering logic to remove old markup from the view when reset happens.