Backbone events not firing (this.el undefined) & general feedback on use of the framework
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Published on 2012-04-05T23:13:44Z
Indexed on
2012/04/05
23:28 UTC
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Filed under:
backbone.js
I am very new to backbone.js and I am struggling a little. I figured out a way to get data from the server (in json) onto the screen successfully but am I doing it the right/best way?
I know there is something wrong because the only view which contains a valid this.el is the parent view. I suspect that because of this, the events of the view are not firing ()... What is the best way forward?
Here is the code:
var surveyUrl = "/api/Survey?format=json&callback=?";
$(function () {
AnswerOption = Backbone.Model.extend({});
AnswerOptionList = Backbone.Collection.extend({
initialize: function (models, options) {
this.bind("add", options.view.render);
}
});
AnswerOptionView = Backbone.View.extend({
initialize: function () {
this.answerOptionList = new AnswerOptionList(null, {
view: this
});
_.bindAll(this, 'render');
},
events: {
"click .answerOptionControl": "updateCheckedState" //does not fire because there is no this.el
},
render: function (model) {
// Compile the template using underscore
var template = _.template($("#questionAnswerOptionTemplate").html(), model.answerOption);
$('#answerOptions' + model.answerOption.questionId + '>fieldset').append(template);
return this;
},
updateCheckedState: function (data) {
//never hit...
}
});
Question = Backbone.Model.extend({});
QuestionList = Backbone.Collection.extend({
initialize: function (models, options) {
this.bind("add", options.view.render);
}
});
QuestionView = Backbone.View.extend({
initialize: function () {
this.questionlist = new QuestionList(null, {
view: this
});
_.bindAll(this, 'render');
},
render: function (model) {
// Compile the template using underscore
var template = _.template($("#questionTemplate").html(), model.question);
$("#questions").append(template);
//append answers using AnswerOptionView
var view = new AnswerOptionView();
for (var i = 0; i < model.question.answerOptions.length; i++) {
var qModel = new AnswerOption();
qModel.answerOption = model.question.answerOptions[i];
qModel.questionChoiceType = ChoiceType();
view.answerOptionList.add(qModel);
}
$('#questions').trigger('create');
return this;
}
});
Survey = Backbone.Model.extend({
url: function () {
return this.get("id") ? surveyUrl + '/' + this.get("id") : surveyUrl;
}
});
SurveyList = Backbone.Collection.extend({
model: Survey,
url: surveyUrl
});
aSurvey = new Survey({
Id: 1
});
SurveyView = Backbone.View.extend({
model: aSurvey,
initialize: function () {
_.bindAll(this, 'render');
this.model.bind('refresh', this.render);
this.model.bind('change', this.render);
this.model.view = this;
},
// Re-render the contents
render: function () {
var view = new QuestionView(); //{el:this.el});
for (var i = 0; i < this.model.attributes[0].questions.length; i++) {
var qModel = new Question();
qModel.question = this.model.attributes[0].questions[i];
view.questionlist.add(qModel);
}
}
});
window.App = new SurveyView(aSurvey);
aSurvey.fetch();
});
-html
<body>
<div id="questions"></div>
<!-- Templates -->
<script type="text/template" id="questionAnswerOptionTemplate">
<input name="answerOptionGroup<%= questionId %>" id="answerOptionInput<%= id %>" type="checkbox" class="answerOptionControl"/>
<label for="answerOptionInput<%= id %>"><%= text %></label>
</script>
<script type="text/template" id="questionTemplate">
<div id="question<%=id %>" class="questionWithCurve">
<h1><%= headerText %></h1>
<h2><%= subText %></h2>
<div data-role="fieldcontain" id="answerOptions<%= id %>" >
<fieldset data-role="controlgroup" data-type="vertical">
<legend> </legend>
</fieldset>
</div>
</div>
</script>
</body>
And the JSON from the server:
? ({
"name": "Survey",
"questions": [{
"surveyId": 1,
"headerText": "Question 1",
"subText": "subtext",
"type": "Choice",
"positionOrder": 1,
"answerOptions": [{
"questionId": 1,
"text": "Question 1 - Option 1",
"positionOrder": 1,
"id": 1,
"createdOn": "\/Date(1333666034297+0100)\/"
}, {
"questionId": 1,
"text": "Question 1 - Option 2",
"positionOrder": 2,
"id": 2,
"createdOn": "\/Date(1333666034340+0100)\/"
}, {
"questionId": 1,
"text": "Question 1 - Option 3",
"positionOrder": 3,
"id": 3,
"createdOn": "\/Date(1333666034350+0100)\/"
}],
"questionValidators": [{
"questionId": 1,
"value": "3",
"type": "MaxAnswers",
"id": 1,
"createdOn": "\/Date(1333666034267+0100)\/"
}, {
"questionId": 1,
"value": "1",
"type": "MinAnswers",
"id": 2,
"createdOn": "\/Date(1333666034283+0100)\/"
}],
"id": 1,
"createdOn": "\/Date(1333666034257+0100)\/"
}, {
"surveyId": 1,
"headerText": "Question 2",
"subText": "subtext",
"type": "Choice",
"positionOrder": 2,
"answerOptions": [{
"questionId": 2,
"text": "Question 2 - Option 1",
"positionOrder": 1,
"id": 4,
"createdOn": "\/Date(1333666034427+0100)\/"
}, {
"questionId": 2,
"text": "Question 2 - Option 2",
"positionOrder": 2,
"id": 5,
"createdOn": "\/Date(1333666034440+0100)\/"
}, {
"questionId": 2,
"text": "Question 2 - Option 3",
"positionOrder": 3,
"id": 6,
"createdOn": "\/Date(1333666034447+0100)\/"
}],
"questionValidators": [{
"questionId": 2,
"value": "3",
"type": "MaxAnswers",
"id": 3,
"createdOn": "\/Date(1333666034407+0100)\/"
}, {
"questionId": 2,
"value": "1",
"type": "MinAnswers",
"id": 4,
"createdOn": "\/Date(1333666034417+0100)\/"
}],
"id": 2,
"createdOn": "\/Date(1333666034377+0100)\/"
}, {
"surveyId": 1,
"headerText": "Question 3",
"subText": "subtext",
"type": "Choice",
"positionOrder": 3,
"answerOptions": [{
"questionId": 3,
"text": "Question 3 - Option 1",
"positionOrder": 1,
"id": 7,
"createdOn": "\/Date(1333666034477+0100)\/"
}, {
"questionId": 3,
"text": "Question 3 - Option 2",
"positionOrder": 2,
"id": 8,
"createdOn": "\/Date(1333666034483+0100)\/"
}, {
"questionId": 3,
"text": "Question 3 - Option 3",
"positionOrder": 3,
"id": 9,
"createdOn": "\/Date(1333666034487+0100)\/"
}],
"questionValidators": [{
"questionId": 3,
"value": "3",
"type": "MaxAnswers",
"id": 5,
"createdOn": "\/Date(1333666034463+0100)\/"
}, {
"questionId": 3,
"value": "1",
"type": "MinAnswers",
"id": 6,
"createdOn": "\/Date(1333666034470+0100)\/"
}],
"id": 3,
"createdOn": "\/Date(1333666034457+0100)\/"
}, {
"surveyId": 1,
"headerText": "Question 4",
"subText": "subtext",
"type": "Choice",
"positionOrder": 4,
"answerOptions": [{
"questionId": 4,
"text": "Question 4 - Option 1",
"positionOrder": 1,
"id": 10,
"createdOn": "\/Date(1333666034500+0100)\/"
}, {
"questionId": 4,
"text": "Question 4 - Option 2",
"positionOrder": 2,
"id": 11,
"createdOn": "\/Date(1333666034507+0100)\/"
}, {
"questionId": 4,
"text": "Question 4 - Option 3",
"positionOrder": 3,
"id": 12,
"createdOn": "\/Date(1333666034507+0100)\/"
}],
"questionValidators": [{
"questionId": 4,
"value": "3",
"type": "MaxAnswers",
"id": 7,
"createdOn": "\/Date(1333666034493+0100)\/"
}, {
"questionId": 4,
"value": "1",
"type": "MinAnswers",
"id": 8,
"createdOn": "\/Date(1333666034497+0100)\/"
}],
"id": 4,
"createdOn": "\/Date(1333666034490+0100)\/"
}],
"id": 1,
"createdOn": "\/Date(1333666034243+0100)\/"
})
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