无法在Google Chrome中将null用作event.dataTransfer.setDragImage的第一个参数

Question

http://help.dottoro.com/ljdpgfkx.php

I'm trying to set position of drag image feedback (the image of a dragged element displayed beside the cursor) with

event.dataTransfer.setDragImage(null, mouseX, mouseY);

and I got Uncaught TypeError: Failed to execute 'setDragImage' on 'DataTransfer': setDragImage: Invalid first argument .

According to http://help.dottoro.com/ljdpgfkx.php . Using null as the first argument should display the default image, but I got the error instead.

Answer 1

I guess null won't work. To use the default image use 'this' or whatever your particular reference to the DOM element being dragged is. Here, for example, I ensure it's centered on the mouse:

event.dataTransfer.setDragImage(this, this.offsetWidth/2, this.offsetHeight/2);

Hope that helps.