长按事件中重复执行代码，变量递增

	var Model = function(){
		this.callParent();
		this.test = justep.Bind.observable(0);
	};
	Model.prototype.button1Touchstart = function(event){
		var me = this;
		this.interval =  setInterval(function(){    //开启定时器
			me.test.set(me.test.get()+ 1 );
      
		},1000); 
	};

	Model.prototype.button1Touchend = function(event){
		 clearInterval(this.interval);  
	};

test案例