jstree crrm.move.check_move cy not always defined - copy

Question

I wanted to implement crrm.move.check_move with the functionality that I can check whether the node is moved or copied and whether the user has the rights to do that. My code looks like this:
var _isUserHasRightToMoveNodes = false; // set depending on user rights
var _isUserHasRightToCopyNodes = true; // set depending on user rights
var _jsTreePlugins = ["themes", "html_data", "ui"];
if ((_isUserHasRightToMoveNodes) || (_isUserHasRightToCopyNodes)) {
_jsTreePlugins.push("dnd");
_jsTreePlugins.push("crrm");
}
$( this ).jstree({
plugins: _jsTreePlugins,
...,
crrm : {
"move" : {
"check_move" : function( m ) {
// wenn der Knoten verschoben wird
if ((!_isUserHasRightToMoveNodes) && ((m.cy == null) || (!m.cy)))
return false;
// wenn der Knoten kopiert wird
if ((!_isUserHasRightToCopyNodes) && (m.cy != null) && (m.cy))
return false;
return true;
}
}
}
});
When I copy a node it appears not to be possible (red cross icon) but it's still being copied (as it should).
I have debugged with firebug and found out, that m.cy is only defined as soon as the node is dropped, but not on mouseover over other nodes, thus the red cross icon. But of course as soon as it is dropped, m.cy is defined and the node is copied, as it's supposed to be.
Am I doing something wrong or is this a bug? Is there any workaround for that?
Thanks for any help!
Tanja

Answer 1

Your return is not as expected - Sample code below should help you:
"crrm": {
"move" : {
"check_move" :
function(tree)
{
//check the condition to enable the drag
if(tree.r.attr("id") != ...){
return {
after : true,
before : false,
inside : false
}
}else{
return false;
}
}
}
}