主干继承，合并render()函数

Question

所以我现在的情况是：

app.Ui.ModalView = Backbone.View.extend({
    events: {

    },

    initialize: function() {

    },

    render: function() {
        var that = this;
        var model = this.model.toJSON();

        that.$el.html(that.template(_.extend(this.params || {}, {
            model: model,
        })));
        return this;
    }
});

然后是继承的视图：

app.Views.childView = kf.Ui.ModalView.extend({

    template: JST["templates/app/blah/blah-edit.html"],
    events: {

    },
    initialize: function() {
        var that = this;
        this.events = _.extend({}, app.Ui.ModalView.prototype.events, this.events);
        app.Ui.ModalView.prototype.initialize.apply(this, arguments);
    },

render: function(){
// add extra logic in this render function, to run as well as the inherited render function?
}

});

所以，我不想重写父级的render()，但是要给它添加额外的功能，我该怎么做呢？

Answer 1

有两种方法可以做到这一点:要么你可以通过在基类中创建一个“呈现钩子”来添加对重写行为的显式支持，要么你必须从超类方法中调用重写的基方法：

基类中的呈现挂钩：

app.Ui.ModalView = Backbone.View.extend({
  render: function() {
    //if this instance (superclass) defines an `onRender` method, call it
    if(this.onRender) this.onRender();

    //...other view code
  }
}

app.Views.childView = kf.Ui.ModalView.extend({
  onRender: function() {
    //your custom code here
  }
});

从超类调用基类方法

app.Views.childView = kf.Ui.ModalView.extend({
  render: function() {
    //your custom code here

    //call the base class `render` method
    kf.Ui.ModalView.prototype.render.apply(this, arguments);
  }
});