These docs are for Marionette 3 which is still in pre-release. Some parts may not be accurate or up-to-date
The CollectionView
will loop through all of the models in the
specified collection, render each of them using a specified childView
,
then append the results of the child view's el
to the collection view's
el
. By default the CollectionView
will maintain a sorted collection's order
in the DOM. This behavior can be disabled by specifying {sort: false}
on initialize.
CollectionView
has the base functionality provided by the View Mixin.
childView
Specify a childView
in your collection view definition. This must be
a Backbone view object definition, not an instance. It can be any
Backbone.View
or be derived from Marionette.View
.
var Mn = require('backbone.marionette');
var MyChildView = Mn.View.extend({});
Mn.CollectionView.extend({
childView: MyChildView
});
Child views must be defined before they are referenced by the
childView
attribute in a collection view definition.
Alternatively, you can specify a childView
in the options for
the constructor:
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({...});
new MyCollectionView({
childView: MyChildView
});
If you do not specify a childView
, an exception will be thrown
stating that you must specify a childView
.
You can also define childView
as a function. In this form, the value
returned by this method is the ChildView
class that will be instantiated
when a Model
needs to be initially rendered. This method also gives you
the ability to customize per Model
ChildViews
.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var FooBar = Bb.Model.extend({
defaults: {
isFoo: false
}
});
var FooView = Mn.View.extend({
template: '#foo-template'
});
var BarView = Mn.View.extend({
template: '#bar-template'
});
var MyCollectionView = Mn.CollectionView.extend({
childView: function(item) {
// Choose which view class to render,
// depending on the properties of the item model
if (item.get('isFoo')) {
return FooView;
}
else {
return BarView;
}
}
});
var collectionView = new MyCollectionView();
var foo = new FooBar({
isFoo: true
});
var bar = new FooBar({
isFoo: false
});
// Renders a FooView
collectionView.collection.add(foo);
// Renders a BarView
collectionView.collection.add(bar);
childViewOptions
There may be scenarios where you need to pass data from your parent
collection view in to each of the childView instances. To do this, provide
a childViewOptions
definition on your collection view as an object
literal. This will be passed to the constructor of your childView as part
of the options
.
var Mn = require('backbone.marionette');
var ChildView = Mn.View.extend({
initialize: function(options) {
console.log(options.foo); // => "bar"
}
});
var CollectionView = Mn.CollectionView.extend({
childView: ChildView,
childViewOptions: {
foo: 'bar'
}
});
You can also specify the childViewOptions
as a function, if you need to
calculate the values to return at runtime. The model will be passed into
the function should you need access to it when calculating
childViewOptions
. The function must return an object, and the attributes
of the object will be copied to the childView
instance's options.
var Mn = require('backbone.marionette');
var CollectionView = Mn.CollectionView.extend({
childViewOptions: function(model, index) {
// do some calculations based on the model
return {
foo: 'bar',
childIndex: index
}
}
});
childViewEventPrefix
You can customize the event prefix for events that are forwarded
through the collection view. To do this, set the childViewEventPrefix
on the collection view. For more information on the childViewEventPrefix
see
"childview:*" event bubbling from child views
var Mn = require('backbone.marionette');
var CV = Mn.CollectionView.extend({
childViewEventPrefix: 'some:prefix'
});
var c = new CV({
collection: myCol
});
c.on('some:prefix:render', function(){
// child view was rendered
});
c.render();
The childViewEventPrefix
can be provided in the view definition or
in the constructor function call, to get a view instance.
childViewEvents
A childViewEvents
hash or method permits handling of child view events without
manually setting bindings. The values of the hash can either be a function or a string
method name on the collection view.
var Mn = require('backbone.marionette');
// childViewEvents can be specified as a hash...
var MyCollectionView = Mn.CollectionView.extend({
childViewEvents: {
// This callback will be called whenever a child is rendered or emits a `render` event
render: function() {
console.log('A child view has been rendered.');
}
}
});
// ...or as a function that returns a hash.
var MyCollectionView = Mn.CollectionView.extend({
childViewEvents: function() {
return {
render: this.onChildRendered
}
},
onChildRendered: function () {
console.log('A child view has been rendered.');
}
});
childViewEvents
also catches custom events fired by a child view.
var Mn = require('backbone.marionette');
// The child view fires a custom event, `show:message`
var ChildView = Mn.View.extend({
// Events hash defines local event handlers that in turn may call `triggerMethod`.
events: {
'click .button': 'onClickButton'
},
// Triggers hash converts DOM events directly to view events catchable on the parent.
// Note that `triggers` automatically pass the first argument as the child view.
triggers: {
'submit form': 'submit:form'
},
onClickButton: function () {
// Both `trigger` and `triggerMethod` events will be caught by parent.
this.trigger('show:message', 'foo');
this.triggerMethod('show:message', 'bar');
}
});
// The parent uses childViewEvents to catch the child view's custom event
var ParentView = Mn.CollectionView.extend({
childView: ChildView,
childViewEvents: {
'show:message': 'onChildShowMessage',
'submit:form': 'onChildSubmitForm'
},
onChildShowMessage: function (message) {
console.log('A child view fired show:message with ' + message);
},
onChildSubmitForm: function (childView) {
console.log('A child view fired submit:form');
}
});
childViewTriggers
A childViewTriggers
hash or method permits proxying of child view events without manually
setting bindings. The values of the hash should be a string of the event to trigger on the parent.
childViewTriggers
is sugar on top of childViewEvents
much
in the same way that View triggers
are sugar for View events
.
var Mn = require('backbone.marionette');
// The child view fires a custom event, `show:message`
var ChildView = Mn.View.extend({
// Events hash defines local event handlers that in turn may call `triggerMethod`.
events: {
'click .button': 'onClickButton'
},
// Triggers hash converts DOM events directly to view events catchable on the parent.
// Note that `triggers` automatically pass the first argument as the child view.
triggers: {
'submit form': 'submit:form'
},
onClickButton: function () {
// Both `trigger` and `triggerMethod` events will be caught by parent.
this.trigger('show:message', 'foo');
this.triggerMethod('show:message', 'bar');
}
});
// The parent uses childViewEvents to catch the child view's custom event
var ParentView = Mn.CollectionView.extend({
childView: ChildView,
childViewTriggers: {
'show:message': 'child:show:message',
'submit:form': 'child:submit:form'
},
onChildShowMessage: function (message) {
console.log('A child view fired show:message with ' + message);
},
onChildSubmitForm: function (childView) {
console.log('A child view fired submit:form');
}
});
The CollectionView
uses Backbone.BabySitter
to store and manage its child views. This allows you to easily access
the views within the collection view, iterate them, find them by
a given indexer such as the view's model or collection, and more.
var Mn = require('backbone.marionette');
var cv = new Mn.CollectionView({
collection: someCollection
});
cv.render();
// retrieve a view by model
var v = cv.children.findByModel(someModel);
// iterate over all of the views and process them
cv.children.each(function(view){
// process the `view` here
});
For more information on the available features and functionality of
the .children
, see the Backbone.BabySitter documentation.
buildChildView
The buildChildView
is responsible for taking the ChildView class and
instantiating it with the appropriate data. This method takes three
parameters and returns a view instance to be used as thechild view.
buildChildView: function(child, ChildViewClass, childViewOptions){
// build the final list of options for the childView class
var options = _.extend({model: child}, childViewOptions);
// create the child view instance
var view = new ChildViewClass(options);
// return it
return view;
},
Override this method when you need a more complicated build, but use childView
if you need to determine which View class to instantiate.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({
childView: function(child) {
if (child.get('type') === 'list') {
return MyListView;
}
return MyView;
},
buildChildView: function(child, ChildViewClass, childViewOptions) {
var options = {};
if (child.get('type') === 'list') {
var childList = new Bb.Collection(child.get('list'));
options = _.extend({collection: childList}, childViewOptions);
} else {
options = _.extend({model: child}, childViewOptions);
}
// create the child view instance
var view = new ChildViewClass(options);
// return it
return view;
}
});
addChildView
The addChildView
method can be used to add a view that is independent of your
Backbone.Collection
. Note that this added view will be subject to filtering
and ordering and may be difficult to manage in complex situations. Use with
care.
This method takes two parameters, the child view instance and the index for where it should be placed within the CollectionView's children.
var Mn = require('backbone.marionette');
Mn.CollectionView.extend({
onRender: function() {
var buttonView = new ButtonView();
this.addChildView(buttonView, this.collection.length);
}
});
removeChildView
The removeChildView
method is useful if you need to remove a view from the CollectionView
without affecting the view's collection. In most cases it is better to use the data to determine what the CollectionView
should display.
This method the child view instance to remove as its parameter.
var Mn = require('backbone.marionette');
Mn.CollectionView.extend({
onChildViewClose: function(childView, model) {
// NOTE: we must wait for the server to confirm
// the destroy PRIOR to removing it from the collection
model.destroy({wait: true});
// but go ahead and remove it visually
this.removeChildView(childView);
}
});
emptyView
When a collection has no children, and you need to render a view other than
the list of childViews, you can specify an emptyView
attribute on your
collection view. The emptyView
just like the childView
can also be passed as an option on instantiation or can be a
function that returns the emptyView
.
var Mn = require('backbone.marionette');
var MyEmptyView = Mn.View.extend({
template: _.template('Nothing to display.')
});
var MyCollectionView = Mn.CollectionView.extend({
// ...
emptyView: MyEmptyView
});
emptyViewOptions
Similar to childView
and childViewOptions
, there is an emptyViewOptions
property that will be passed to the emptyView
constructor. It can be provided as an object literal or as a function.
If emptyViewOptions
aren't provided the CollectionView
will default to passing the childViewOptions
to the emptyView
.
var Mn = require('backbone.marionette');
var EmptyView = Mn.View({
initialize: function(options){
console.log(options.foo); // => "bar"
}
});
var CollectionView = Mn.CollectionView({
emptyView: EmptyView,
emptyViewOptions: {
foo: 'bar'
}
});
isEmpty
If you want to control when the empty view is rendered, you can override
isEmpty
:
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({
isEmpty: function(options) {
// some logic to calculate if the view should be rendered as empty
return this.collection.length < 2;
}
});
render
The render
method of the collection view is responsible for
rendering the entire collection. It loops through each of the
children in the collection and renders them individually as a
childView
. By default when a collectionView
is fully rendered it buffers the DOM changes for a single attachBuffer
] DOM change.
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({...});
// all of the children views will now be rendered.
new MyCollectionView().render();
For more information on rendering techiniques see: Rendering CollectionView
s.
After the initial render the collection view binds to the "add", "remove" and "reset" events of the collection that is specified.
When the collection for the view is "reset", the view will call render
on
itself and re-render the entire collection.
When a model is added to the collection, the collection view will render that one model in to the collection of child views.
When a model is removed from a collection (or destroyed / deleted), the collection view will destroy and remove that model's child view.
When the collection for the view is sorted, the view will automatically re-sort its child views.
If the reorderOnSort
option is set it will attempt to reorder the DOM and do this without a full re-render, otherwise it will re-render if the order has changed. Please Note that if you apply a filter to the collection view and the filtered views change during a sort then it will always re-render.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var collection = new Bb.Collection();
var MyChildView = Mn.View.extend({
template: false
});
var MyCollectionView = Mn.CollectionView.extend({
childView: MyChildView,
collection: collection,
});
var myCollectionView = new MyCollectionView();
// Collection view will not re-render as it has not been rendered
collection.reset([{foo: 'foo'}]);
myCollectionView.render();
// Collection view will re-render displaying the new model
collection.reset([{foo: 'bar'}]);
If you need to re-render the entire collection, you can call the
view.render
method. This method takes care of destroying all of
the child views that may have previously been opened.
attachHtml
By default the collection view will append the HTML of each ChildView
into the element buffer, and then call jQuery's .append
once at the
end to move the HTML into the collection view's el
.
You can override this by specifying an attachHtml
method in your
view definition. This method takes three parameters and has no return
value.
var Mn = require('backbone.marionette');
Mn.CollectionView.extend({
// The default implementation:
attachHtml: function(collectionView, childView, index){
if (collectionView._isBuffering) {
// buffering happens on reset events and initial renders
// in order to reduce the number of inserts into the
// document, which are expensive.
collectionView._bufferedChildren.splice(index, 0, childView);
} else {
// If we've already rendered the main collection, append
// the new child into the correct order if we need to. Otherwise
// append to the end.
if (!collectionView._insertBefore(childView, index)){
collectionView._insertAfter(childView);
}
}
}
});
The first parameter is the instance of the collection view that will receive the HTML from the second parameter, the current child view instance.
The third parameter, index
, is the index of the
model that this childView
instance represents, in the collection
that the model came from. This is useful for understanding the sort order of the children.
Overrides of attachHtml
that don't take into account the element
buffer will work fine, but won't take advantage of the 60x performance
increase the buffer provides.
attachBuffer
When overriding attachHtml
it may be necessary to also override how the buffer is attached. This method receives two parameters. The collectionView
and the buffer HTML of all of the child views.
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({
// The default implementation:
// Called after all children have been appended into the buffer
attachBuffer: function(collectionView, buffer) {
collectionView.$el.append(buffer);
}
});
destroy
CollectionView
implements a destroy
method which automatically
destroys its children and cleans up listeners.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var MyChildView = Mn.View.extend({
template: _.template('ChildView'),
onDestroy: function() {
console.log('I will get destroyed');
}
})
var myCollectionView = new Mn.CollectionView({
childView: MyChildView,
collection: new Bb.Collection([{ id: 1 }])
});
myCollectionView.render();
myCollectionView.destroy(); // logs "I will get destroyed"
filter
CollectionView
allows for a custom filter
option if you want to prevent some of the
underlying collection
's models from being rendered as child views.
The filter function takes a model from the collection and returns a truthy value if the child should be rendered,
and a falsey value if it should not.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var cv = new Mn.CollectionView({
childView: SomeChildView,
emptyView: SomeEmptyView,
collection: new Bb.Collection([
{ value: 1 },
{ value: 2 },
{ value: 3 },
{ value: 4 }
]),
// Only show views with even values
filter: function (child, index, collection) {
return child.get('value') % 2 === 0;
}
});
// renders the views with values '2' and '4'
cv.render();
// change the filter
// renders the views with values '1' and '3'
cv.setFilter(function (child, index, collection) {
return child.get('value') % 2 !== 0;
});
// renders all views
cv.removeFilter();
setFilter
The setFilter
method modifies the CollectionView
's filter attribute, and
renders the new ChildViews
in a efficient way, instead of
rendering the whole DOM structure again.
Passing { preventRender: true }
in the options argument will prevent the view being rendered.
var Mn = require('backbone.marionette');
var cv = new Mn.CollectionView({
collection: someCollection
});
cv.render();
var newFilter = function(child, index, collection) {
return child.get('value') % 2 === 0;
};
// Note: the setFilter is preventing the automatic re-render
cv.setFilter(newFilter, { preventRender: true });
//Render the new state of the ChildViews instead of the whole DOM.
cv.render();
removeFilter
This function is actually an alias of setFilter(null, options)
. It is useful for removing filters.
removeFilter
also accepts preventRender
as a option.
var Mn = require('backbone.marionette');
var cv = new Mn.CollectionView({
collection: someCollection
});
cv.render();
cv.setFilter(function(child, index, collection) {
return child.get('value') % 2 === 0;
});
//Remove the current filter without rendering again.
cv.removeFilter({ preventRender: true });
sort
By default the CollectionView
will maintain a sorted collection's order
in the DOM. This behavior can be disabled by specifying {sort: false}
on initialize. The sort
flag cannot be changed after instantiation.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var myCollection = new Bb.Collection([
{ id: 1 },
{ id: 4 },
{ id: 3 },
{ id: 2 }
]);
myCollection.comparator = 'id';
var mySortedColView = new Mn.CollectionView({
//...
collection: myCollection
});
var myUnsortedColView = new Mn.CollectionView({
//...
collection: myCollection,
sort: false
});
mySortedColView.render(); // 1 4 3 2
myUnsortedColView.render(); // 1 4 3 2
// mySortedColView auto-renders 1 2 3 4
// myUnsortedColView has no change
myCollection.sort();
viewComparator
CollectionView
allows for a custom viewComparator
option if you want your CollectionView
's children to be rendered with a different sort order than the underlying Backbone collection uses.
var Mn = require('backbone.marionette');
var cv = new Mn.CollectionView({
collection: someCollection,
viewComparator: 'otherFieldToSortOn'
});
The viewComparator
can take any of the acceptable Backbone.Collection
comparator formats -- a sortBy
(pass a function that takes a single argument), as a sort (pass a comparator
function that expects two arguments), or as a string indicating the attribute to
sort by.
getViewComparator
Override this method to determine which viewComparator
to use.
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({
sortAsc: function(model) {
return -model.get('order');
},
sortDesc: function(model) {
return model.get('order');
},
getViewComparator: function() {
// The collectionView's model
if (this.model.get('sorted') === 'ASC') {
return this.sortAsc;
}
return this.sortDesc;
}
});
reorderOnSort
This option is useful when you have performance issues when you resort your CollectionView
.
Without this option, your CollectionView
will be completely re-rendered, which can be
costly if you have a large number of elements or if your ChildView
s are complex. If this option
is activated, when you sort your Collection
, there will be no re-rendering, only the DOM nodes
will be reordered. This can be a problem if your ChildView
s use their collection's index
in their rendering. In this case, you cannot use this option as you need to re-render each
ChildView
.
If you combine this option with a filter that changes the views that are
to be displayed, reorderOnSort
will be bypassed to render new children and remove those that are rejected by the filter.
reorder
If reorderOnSort
is set to true, this function will be used instead of re-rendering all children. It can be called directly to prevent the collection from being completely re-rendered. This may only be useful if models are added or removed silently or if sort
was set to false on the CollectionView
.
resortView
By default the CollectionView
will maintain the order of its collection
in the DOM. However on occasions the view may need to re-render to make this
possible, for example if you were to change the comparator on the collection.
The CollectionView
will re-render its children or reorder
them depending on reorderOnSort
.
Override this function if you need further customization.
var Mn = require('backbone.marionette');
var MyCollectionView = Mn.CollectionView.extend({
resortView: function() {
// provide custom logic for rendering after sorting the collection
}
});
There are several events that will be triggered during the life of a collection view. Each of these events is called with the Marionette.triggerMethod function, which calls a corresponding "on{EventName}" method on the view instance. Additionally each event is triggered immediately after the action occurred and a before event is triggered immediately prior. The first argument passed to all event handlers is the triggering view.
Triggers when the CollectionView
is rendered.
You can implement this in your view to provide custom code for dealing
with the view's el
after it has been rendered:
var Mn = require('backbone.marionette');
var MyView = Mn.CollectionView.extend({...});
var myView = new MyView();
myView.on({
'render': function() {
console.log('this collection view rendered');
},
'before:render': function(){
console.log('the collection view is about to be rendered');
}
});
myView.render();
The render:children
event is triggered after a collectionView
's children have been rendered and buffered. It differs from the collectionViews
's render
event in that it happens only if the collection
is not not empty. It may also happen when the children sort when reorderOnSort
is false.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var MyView = Mn.CollectionView.extend({...});
var myView = new MyView({
collection: new Bb.Collection([{ id: 1 }]);
});
myView.on({
'render': function() {
console.log('this collection view childen were rendered');
},
'before:render': function(){
console.log('the collection view children are about to be rendered');
}
});
myView.render();
Triggered just after destroying the view. onBeforeDestroy
is the optimal function for any additional necessary cleanup within the collectionView
.
var Mn = require('backbone.marionette');
var MyView = Mn.CollectionView.extend({...});
var myView = new MyView();
myView.on({
'destroy': function() {
console.log('this collection view is destroyed');
},
'before:destroy': function(){
console.log('this is the best place to clean up additional listeners');
}
});
myView.destroy();
Triggered when the collectionView
is destroyed or before the collectionView
's children are re-rendered.
var Mn = require('backbone.marionette');
var MyView = Mn.CollectionView.extend({...});
var myView = new MyView();
myView.on({
'destroy:children': function() {
console.log('this collection view is destroyed');
},
'before:destroy': function(){
console.log('this is the best place to clean up additional listeners');
}
});
// destroy:children not triggered on first render
myView.render();
// destroy:children triggered
myView.render();
// destroy:children triggered
myView.destroy();
The "add:child" event is triggered after rendering the view and adding it to the view's DOM element.
var cv = new MyCV({...});
cv.on({
'add:child': function() {
console.log('this will be called for each child added to the DOM');
},
'before:add:child': function(){
console.log('before each child is rendered and added to the DOM');
}
});
Triggered when a childView instance has been destroyed and removed, when its child was deleted or removed from the collection.
cv.on({
'remove:child': function() {
console.log('this will be called for each child removed from the collectionView');
},
'before:remove:child': function(){
console.log('before each child is destroyed and removed');
}
});
The "render:empty"
event is triggered when rendering the empty view and adding it to the view's DOM element.
var Mn = require('backbone.marionette');
var myEmptyView = Mn.View.extend({
template: false
});
var MyCollectionView = Mn.CollectionView.extend({
emptyView: myEmptyView
});
var myCollectionView = new MyCollectionView();
myCollectionView.on({
'render:empty': function() {
console.log('the empty view has been rendered');
},
'before:render:empty': function() {
console.log('before the empty view has been rendered');
}
});
myCollectionView.render()
Triggered just after destroying the empty view from the DOM.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var collection = new Bb.Collection();
var myChildView = Mn.View.extend({
template: false
});
var myEmptyView = Mn.View.extend({
template: false
});
var MyCollectionView = Mn.CollectionView.extend({
childView: myChildView,
collection: collection,
emptyView: myEmptyView
});
var myCollectionView = new MyCollectionView();
myCollectionView.on({
'remove:empty': function() {
console.log('the empty view has been removed');
},
'before:remove:empty': function() {
console.log('before the empty view is removed');
}
});
myCollectionView.render()
collection.add([{foo: 'bar'}])
When reorderOnSort
is set to true
, these events are fired for the reordering of the collection.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var MyView = Mn.CollectionView.extend({...});
var myCol = new Bb.Collection({ comparator: ... })
var myView = new MyView({ reorderOnSort: true });
myView.render();
myCol.comparator = function () { return this.get('foo'); };
myView.on({
'remove:empty': function() {
console.log('the collection view has been reordered following its collection');
},
'before:remove:empty': function() {
console.log('the collection view is about to be reordered');
}
});
myCol.sort()
When a child view within a collection view triggers an
event, that event will bubble up through the parent
collection view with the childViewEventPrefix
(which defaults to "childview:") prepended to the event name.
That is, if a child view triggers "do:something", the parent collection view will then trigger "childview:do:something".
var Mn = require('backbone.marionette');
// set up basic collection
var myModel = new MyModel();
var myCollection = new MyCollection();
myCollection.add(myModel);
var MyView = Mn.View.extend({
triggers: {
'click button': 'do:something'
}
});
// get the collection view in place
var colView = new CollectionView({
collection: myCollection,
childView: MyView,
onChildviewDoSomething: function() {
console.log('I said, "do something!"');
}
});
colView.render();
Now, whenever the button inside the attached childView is clicked, a console log will appear that says: I said, "do something!"
It's also possible to attach the event manually using the usual
view.on('childview:do:something')
.
The following events are raised on child views during rendering and destruction of child views, which is consistent with the view lifecycle experienced during Region#show
.
render
/ onRender
- Called after the view is rendered, but before it is attached to the DOM.attach
/ onAttach
- Called after the view is attached to the DOM. This will not fire if the CollectionView
itself is not attached.dom:refresh
/ onDomRefresh
- Called when the view is rendered but only if it is attached to the DOM. This will not fire if the CollectionView
itself is not attached.destroy
/ onDestroy
- Called after destroying a view.Note: These events are triggered on pure Backbone Views during child view rendering, but for a complete implementation of these events the Backbone View should fire render
within render()
and destroy
within remove()
as well as set the following flags:
view.supportsRenderLifecycle = true;
view.supportsDestroyLifecycle = true;
CollectionView
sMarionette 3 has completely removed the CompositeView
in favor making the
View
and CollectionView
a lot more flexible. This section will cover the
most common use cases for CollectionView
and how to replace CompositeView
.
Lists are possibly the simplest use of CollectionView
- simply set a
childView
option:
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var ListItemView = Mn.View.extend({
tagName: 'li',
template: '#list-item-text'
});
var ListView = Mn.View.extend({
tagName: 'ul',
className: 'list-unstyled',
childView: ListItemView
});
var list = new Bb.Collection([
{id: 1, text: 'My text'},
{id: 2, text: 'Another Item'}
]);
var listView = new ListView({
collection: list
});
listview.render();
With the template:
<%- text %>
This will render the following:
<ul class="list-unstyled">
<li>My text</li>
<li>Another Item</li>
</ul>
Marionette 3 introduced a major improvement to View
to make it possible to
implement tables using only View
and CollectionView
. This section will
demonstrate how to build a table in Marionette 3, with the equivalent in
Marionette 2 using CompositeView
.
The following code is deprecated and for demonstration purposes only
To build a table in Marionette 2 requires the CompositeView
which we'll build
as such:
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var RowView = Mn.LayoutView.extend({
tagName: 'tr',
template: '#table-row'
});
var TableView = Mn.CompositeView.extend({
tagName: 'table',
className: 'table table-hover',
template: '#table',
childView: RowView,
childViewContainer: 'tbody'
});
var list = new Bb.Collection([
{id: 1, text: 'My text'},
{id: 2, text: 'Another Item'}
]);
var myTable = new TableView({
collection: list
});
myTable.render();
Given the following #table
and #table-row
templates:
<thead>
<tr>
<th>ID</th>
<th>Body</th>
</tr>
</thead>
<tbody></tbody>
<td><%- id %></td>
<td><%- text %></td>
Will render the following:
<table class="table table-hover">
<thead>
<tr>
<th>ID</th>
<th>Body</th>
</tr>
</thead>
<tbody>
<tr>
<td>1</td>
<td>My text</td>
</tr>
<tr>
<td>2</td>
<td>Another Item</td>
</tr>
</tbody>
</table>
###
A major downside of this method was that it was impossible to add extra regions
inside the CompositeView
- if a header item needed to be re-rendered based on
user input, then the entire table must be re-rendered, or the DOM must be
manipulated with ui
items.
To resolve this issue, Marionette 3 improves the View
to make it possible to
build tables without CompositeView
.
Marionette 3 doesn't use CompositeView
any more. We now build tables using
View
s and regions
. The following code will render the same table as in
Marionette 2:
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var RowView = Mn.View.extend({
tagName: 'tr',
template: '#row-template'
});
var TableBody = Mn.CollectionView.extend({
tagName: 'tbody',
childView: RowView
});
var TableView = Mn.View.extend({
tagName: 'table',
className: 'table table-hover',
template: '#table',
regions: {
body: {
el: 'tbody',
replaceElement: true
}
},
onRender: function() {
this.showChildView('body', new TableBody({
collection: this.collection
}));
}
});
var list = new Bb.Collection([
{id: 1, text: 'My text'},
{id: 2, text: 'Another Item'}
]);
var myTable = new TableView({
collection: list
});
myTable.render();
We can leave the templates as-is for this example. The major advantage of this
style is that we can create a region in any part of TableView
as well as in
RowView
and treat it just as any independent widget.
Tree structures are extremely useful layouts for nesting the same type of data over and over. A common example of this would be the Windows Explorer file picker.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var TreeView = Mn.CompositeView.extend({
tagName: 'ul',
template: '#tree-template'
});
var TreeRoot = Mn.CollectionView.extend({
tagName: 'ul',
childView: TreeView
});
var tree = new Bb.Collection([
{
id: 5,
nodes: [
{id: 9, nodes: []},
{id: 1, nodes: [...]}
],
},
{
id: 12,
nodes: []
}
]);
new TreeRoot({
collection: tree
});
In Marionette 2, the CompositeView
defaults to setting childView
to itself.
While good for building tree structures, this behavior changed for Marionette 3
with the introduction of a more general view.
As in tables, trees in Marionette 3 require us to combine View
and
CollectionView
to build up the tree in a more explicit manner than the
implicit version provided by Marionette 2.
var Bb = require('backbone');
var Mn = require('backbone.marionette');
var TreeNode = Mn.View.extend({
tagName: 'li',
template: '#tree-template',
regions: {
tree: {
el: 'ul',
replaceElement: true
}
},
onRender: function() {
this.showChildView('tree', new TreeView({
collection: new Bb.Collection(this.model.get('nodes'))
}));
}
});
var TreeView = Mn.CollectionView.extend({
tagName: 'ul',
childView: TreeNode
});
var tree = new Bb.Collection([
{
id: 5,
nodes: [
{id: 9, nodes: []},
{id: 1, nodes: [...]}
],
},
{
id: 12,
nodes: []
}
]);
new TreeView({
collection: tree
});
This more explicit style gives us two major benefits:
CompositeView