var qcanvas = new Qcanvas(
		{
			id:'qcanvas',
			width:500,
			height:500,  
			mousedown:function(){
				document.getElementById('contextMenu').style.display = 'none';
			}
		})

    var text = qcanvas.qtext.text({
		start:[100,100],
		color:'blue',
		fontSize:'20px',
		mousedown:function(){
				document.getElementById('contextMenu').style.display = 'none';
			},
		mouseup:function(e,pos){

			if(e.button == '2'){
				console.log('text右击');

				var doc = document.getElementById('qcanvas_lay')
				var left = pos.x - doc.scrollLeft;
				var top = pos.y - doc.scrollTop;

				var contextMenu = document.getElementById('contextMenu');
				contextMenu.style.left = left+'px';
				contextMenu.style.top = top+'px';
				contextMenu.style.display = "block";
			} 

		},
	})