如何在使用jQuery拖动时处理停止事件

我有一个处理拖动鼠标（而不是内容）的插件，在开始拖动处理程序中，我正在创建另一个触发拖动并停止父级的元素，但它不起作用（父级仍在调用dragHandler）：
（原因是我可以在拖动鼠标时缩放/平移。）
start在mousedown上调用，它还为mousemove等注册侦听器。
在mouseup上调用end，这也会删除侦听器。

http://jsfiddle.net/62XZU/7/

<svg></svg>

插件：

(function($) {
    $.fn.ondrag = function(opt) {
        //console.log("set drag");
        var obj = this;
        opt = $.extend({start:null,drag:null,end:null,leave:null,dropElement:document}, opt);
        this.data('ondrag',opt);
        opt.dragHandler = function(e){ if (opt.drag) opt.drag.call(obj); e.stopPropagation(); };
        opt.leaveHandler = function(e){ if (opt.leave) opt.leave.call(obj); e.stopPropagation(); };
        opt.startHandler = function(e){
            if (opt.start) opt.start.call(obj); 
            $(document).on("mousemove",opt.dragHandler); 
            $(document.body).on("mouseleave",opt.leaveHandler); 
            $(document).on("mouseup",opt.endHandler); e.stopPropagation(); };
        opt.endHandler = function(e){ 
            if (opt.end) opt.end.call(obj); 
            $(document).off("mousemove",opt.dragHandler); 
            $(document.body).off("mouseleave",opt.leaveHandler); 
            $(document).off("mouseup",opt.endHandler); e.stopPropagation(); };
        this.on("mousedown",opt.startHandler);
        opt.stopdrag = function(){ //this should remove the svg listeners to stop dragging
            console.log("stop dragging", opt.drag);
            if (opt.end) opt.end.call(obj);
            $(document).off("mousemove",opt.dragHandler);
            $(document.body).off("mouseleave",opt.leaveHandler);
            $(document).off("mouseup",opt.endHandler);
        };
        return this;
    };
})(jQuery);

实施：

$('svg').ondrag({
    start: function(){
        if (event.which==1) {//pan on left click
        } else { //create new element with drag and svg stop dragging
            console.log("started dragging on svg");
            $(document).trigger("mouseup"); //not working (svg is still dragging)
            this.data('ondrag').stopdrag(); //not working
            $(document.createElementNS('http://www.w3.org/2000/svg', 'circle'))
                .attr({r:50,fill:"lightgray",cx:"50%",cy:"50%"})
                .ondrag({
                    start:function(){ console.log("started dragging circle"); }, 
                    drag:function(){ console.log("dragging circle"); }
                }).appendTo(this).trigger("mousedown");
        }
    }, drag: function(){ console.log("dragging on svg"); }
});