我尝试使用this Backbone.js演示根据滑块位置动态更新字段。但是,当调用updateVal
处理程序时,它似乎无法识别DOM元素的.slider
属性。第一次使用Backbone / js MVC框架,所以欢迎任何/所有的智慧词。
这是错误的屏幕截图
主干应用
$(document).ready(function () {
// Initialize jquery slider
$("#slider").slider();
// Create the model class via Backbone (which sets up things like prototype objects correctly).
// This particular model is a very simple one. It'll have just 1 attribute - "slidervalue"
var SliderModel = Backbone.Model.extend({});
// A "View" abstraction for the slider.
// Whenever the slider position changes, this view updates the model with the new value.
var SliderView = Backbone.View.extend({
el: $("#slider"), // Specifies the DOM element which this view handles
events: {
// Call the event handler "updateVal" when slider value changes.
// 'slidechange' is the jquery slider widget's event type.
// Refer http://jqueryui.com/demos/slider/#default for information about 'slidechange'.
"slidestart": "updateVal",
"slidestop" : "updateVal"
},
updateVal: function () {
// Get slider value and set it in model using model's 'set' method.
console.log('SliderView.updateVal');
var val = this.el.slider("option", "value");
this.model.set({ slidervalue: val });
}
});
// The listener "View" for the model.
// Whenever the model's slidervalue attribute changes, this view receives the updated value.
var ValueView = Backbone.View.extend({
initialize: function (args) {
// _.bindAll is provided by underscore.js.
// Due to some javascript quirks, event handlers which are bound receive a 'this'
// value which is "useless" (according to underscore's docs).
// _.bindAll is a hack that ensures that 'this' in event handler refers to this view.
_.bindAll(this, 'updateValue');
console.log('ValueView.initialize');
// Bind an event handler to receive updates from the model whenever its
// 'slidervalue' attribute changes.
this.model.bind('change:slidervalue', this.updateValue);
console.log(this);
},
updateValue: function () {
// Get the slider value from model, and display it in textbox.
console.log('ValueView.updateValue');
// this.model won't work unless "_.bindAll(this, ...)" has been called in initialize
var value = this.model.get('slidervalue');
console.log(value);
$("#sliderVal").val(value);
}
});
// Create the instances
var sliderModel = new SliderModel;
var sliderView = new SliderView({ model: sliderModel });
var valView = new ValueView({ model: sliderModel });
});
HTML
<!-- "slider" is a jquery slider -->
<div id="slider"></div>
<!-- "sliderVal" displays the slider's position. It receives the value via model. -->
<input type="text" id="sliderVal" value="0"/>
答案 0 :(得分:1)
尝试
var val = this.$el.slider("option", "value");
View.el是实际的DOM对象,View。$ el包含在jquery对象中。