Question

我有一个视图，不是窗口的大小，也不是窗口本身，当它调整大小时，我想比较调整大小的开始和结束值。然而，JQ-UI的resize ui对象仅包含前一个状态，而不是原始状态，因此它只是按像素抓取更改（虽然我认为这是因为我将代码放在resize函数中，而不是end函数，但是这不是真正的问题，因为一旦我知道如何将var恢复到Backbone View本身就可以解决它。如何从调整大小中获取信息回到主干视图？ self是全局window对象，this是this.el选择器的JQuery结果。

define([ ... ], function( ... ){
  return Backbone.View.extend({
    // I also tried to use the event handlers from backbone
    events : {
      'resize' : 'info'
    },
    initialize: function(options){
      if (options) { ... }
        this.el = '#measure-rep-c55';
      }
      //Dispatch listeners
      ...
      //Binding
      this.model.bind('change', _.bind(this.render, this));
      $(this.el).on('resize', this.info);  // Here I am trying to attach the listener here according the API

      this.render();
    },
    info: function(){
      console.log('in info')
    },
    render: function(){ 
      ... //template and other stuff

      // JQ-UI resizable
      $(this.el).resizable({ 
        aspectRatio: true,
        start: function(e, ui) {
            // alert('resizing started');
        },
        resize: function( event, ui ) {
          // in here self = window
          // and this is the JQuery object
          var oldW = ui.originalSize.width;
          var newW = ui.size.width;
          var deltaWidth = newW - oldW;
          var deltaRatio = deltaWidth/oldW;
          //HOW TO SEND info (in this case var deltaRatio) back to the backbone view
          //I tried getting to the function info() so that I could access the View itself from there
        },
        stop: function(e, ui) {
            // alert('resizing stopped');
        }
      });
    },
  });
});

Answer 1

不要在可调整大小的调用中创建侦听器，使用events hash来侦听更改，然后您可以从回调中直接访问视图。

events : {
  'resizestart' : 'start',
  'resizestop' : 'stop',
  'resize' : 'resize'
},

render: function(){ 
  ... //template and other stuff

  // JQ-UI resizable
  this.$el.resizable({ 
    aspectRatio: true
  });
},

start: function(e, ui) {
        // alert('resizing started');
},
resize: function( event, ui ) {
      // this is the View
      var oldW = ui.originalSize.width;
      var newW = ui.size.width;
      var deltaWidth = newW - oldW;
      var deltaRatio = deltaWidth/oldW;
 },
 stop: function(e, ui) {
    // alert('resizing stopped');
 }

Answer 2

您可以使用下划线来绑定视图＆＃39;这个＆＃39;到事件函数，它将使您可以访问视图本身。我通常将函数体分成它们自己的函数，如下所示：

render: function() { 
  ...
  this.$el.resizable({
    aspectRatio: true,
    start: _.bind(this.didStart, this),
    resize: _.bind(this.didResize, this),
    end: _.bind(this.didEnd, this)
  });
},

didStart: function() {
  ...
},

didResize: function() {
  ...
},

didEnd: function() {
  ...
}

JQuery UI可调整大小调整事件绑定/调整大小事件到Backbone View

2 个答案: