javascript - Filtering and Rendering in Backbone -


i'm new backbone , have been testing different ways filter , render collection. i'm building simple todo app. model looks this:

{ description: "go hike", display: "show" }

i want use search-box filter todos based on "description" property.

as of now, on every 'keyup' iterate through collection , see if each model's description includes value of search-box. if model not include value of search-box change it's "display" property "hide", else keep/change "show".

after i've changed 'display' property on every model instance render collection. collectionview renders models 'display' property === 'show'

it turn out pretty slow. can suggest better way of filtering , rendering collection on every 'keyup' ?

here filter code:

  filterresults: function() {     // value respresents value of search-box     var value = this.$el.val();     todolist.foreach( function (item) {       if (item.get('description').indexof(value) > -1) {         item.set({display: 'show'});       }else {         item.set({display: "hide"});       }     });     todolistview.render();   }

here the collectionview code:

todolistview = backbone.view.extend({   addone: function(todoitem) {     if (todoitem.get('display') === "show") {       var todoview = new todoview({model: todoitem});       todoview.render();       this.$el.append(todoview.el);     }   },   render: function() {     this.$el.html("");     this.collection.foreach(this.addone, this);   },

i appreciate feedback, thanks!

you have 2 foreach blocs, depending of size of collection, can little slow...

can call render() when perform set on model? way avoid 1 foreach. maybe change how check if model have 'show' property, if you're focused on performance, try compare int instead of string.

i advise use http://www.datatables.net/, it's avery plugin , you.

hope helps.


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