Question

我正在尝试加载国家/地区列表并选择我想要调用警报的国家/地区，但不知何故我无法捕获选择框的更改事件。

有人可以帮帮我吗？

这里是带有视图，模型和集合部分的代码，其中包含html中的模板脚本

    <!DOCTYPE html>
<html>
<head>
    <title>Backbone</title>
</head>
<body>
    <script type="text/template" id="country_select_template">
        <select id="country-selector">
             <% _.each(countries, function(country) {%>
                <option value="<%= country.fipsCode %>"><%= country.countryName %></option>
            <% }); %>
        </select>
    </script>
    <div id="country_select_container">
        Loading country...
    </div>

    <!--div>
    <select id="state" disabled=true>
        <option value="NAN">Select State</option>                    
    </select>
    </div>
    <div>
    <select id="city" disabled=true>
        <option value="NAN">Select City</option>                    
    </select>
    </div-->
</div>
<ul id="names-list">
</ul>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
<script src="http://ajax.cdnjs.com/ajax/libs/underscore.js/1.1.4/underscore-min.js"></script>
<script src="http://ajax.cdnjs.com/ajax/libs/backbone.js/0.3.3/backbone-min.js"></script>
<script>

Country = Backbone.Model.extend();

CountryList = Backbone.Collection.extend({
    model : Country,
    url : "https://dl.dropbox.com/u/18190667/countryList.json",
    parse : function(response) {
        return response.geonames;
    }
});

Countries = new CountryList();

CountryView = Backbone.View.extend({
    events: {
        "change #country-selector": "countrySelected"
    },

    countrySelected: function(){
        alert("You can procceed!!!");
    },

    countrySelected  :function(){
        alert("Procceed");
    },

    initialize: function(){
        var countries = [];
        var self = this;
        Countries.fetch({
            success: function(){
                self.render();
            }
        });
    },

    render: function(){
        var self = this;
        var country_select_template = _.template($("#country_select_template").html(), {
            countries: Countries.toJSON(),
        });
        $('#country_select_container').html(country_select_template);
        return this;
    }
});
var view = new CountryView();
</script>

</body>
</html>

Answer 1

试试这样：

CountryView = Backbone.View.extend({
    el: $("#country_select_container"),
    template: _.template($("#country_select_template").html()),
    events: {
        "change #country-selector": "countrySelected"
    },

    countrySelected: function(){
        alert("You can procceed!!!");
    },

    initialize: function(){
        var self = this;
        Countries.fetch({
            success: function(){
                self.render();
            }
        });
    },

    render: function(){
        this.$el.html(
           this.template({countries: Countries.toJSON()})
        );
        return this;
    }
});

有关详情，请查看here，希望这会有所帮助：）

Answer 2

您必须将视图绑定到现有DOM元素。试试这个：

CountryView = Backbone.View.extend({

    el:'#country-selector',

    events: {
        "change #country-selector": "countrySelected"
    },

...

或者在您的情况下，您可以将el参数作为参数传递给构造函数：

new CountryView({el:'#country-selector'});

如果您没有将el绑定到现有DOM元素，则骨干网默认会将其绑定到div。因此，您的事件将被触发查找div > #country-selector并且将不匹配，因为不存在此类元素。

如何在Backbone中绑定更改事件？

2 个答案: