backbone.js - Backbone.Model validation and isValid -

i have set model validation below

• full coffeescript code: http://pastebin.com/3iszzke8
• demo on js fiddle: http://jsfiddle.net/xktnb/

model's validation

class todo extends backbone.model      validate: (attrs) ->          errs = {}         haserrors = false          if (attrs.title "")             haserrors = true             errs.title = "please specify todo"          if haserrors             return errs 

error related code in view

class todoview extends backbone.view      events:         "keypress .editing input[name=todo]": "savetodo"         "keyup .editing input[name=todo]": "closeedit"          "blur input[name=todo]": "clearerrors"      initialize: ->          ...         @model.bind("change", @render)         @model.bind("error", @handleerror)      savetodo: (e) ->         if e.type "keypress" , e.charcode isnt 13             return         @model.set("title": @$("input[name=todo]").val())         console.log @$("input[name=todo]").val() + "...", @model.isvalid(), @model.get("title")         if @model.isvalid()             @closeedit()      closeedit: (e) ->         if (e)             if e.type "keyup" , e.keycode isnt 27 return         @$el.removeclass("editing")       handleerror: (model, errs) ->         @clearerrors()         @$("input[name=todo]").after($("<span />", {             class: "error",             html: errs.title         }));         console.log "error handled"      clearerrors: ->         @$el.remove(".error") 

in todoview.savetodo, check if model valid, if so, expect save successful , want out of edit edit mode. however, appears isvalid true, maybe because validation occurs , model not saved in valid state?

update

added link js fiddle above. try adding todo, try make todo blank. notice closes edit mode although in code had:

savetodo: (e) ->     if e.type "keypress" , e.charcode isnt 13         return     @model.set("title", @$("input[name=todo]").val())     if @model.isvalid() # model appears valid here!         @model.save()         @closeedit()  

now double click go edit mode, notice error there meaning validation done correctly

i don't understand question read have model in try save information you've entered.

the models validate method automatically return error on setting values of model.

for instance:

var todomodel = backbone.model.extend({       defaults: {        title: '',        closed: 'false'     },      validate: function(attr) {          if (attr.title === '') {             console.log("title expected");         }      } }); 

now when create new instance of object (so did not save information in model yet) model isvalid return false:

var todo = new todomodel(); console.log(todo.isvalid()); //will false 

i don't know got save function from. if place data todo model can this:

var todo = new todomodel(); todo.set({     'title': 'figure out backbone js' });  console.log(todo.isvalid()); //must return true 

of course can set these values imediatly:

var todo = new todomodel({     'title': 'still figuring out' });  console.log(todo.isvalid()); //still returns true 

so way validation checking.