Loading indicator for expandall function

Is there a function or a solution to display a loading image/text indicator for the expandall function on dhtmlxtreegrid.



My company just recently purchased the 1.6 enterprise license.

The expandAll operation is a sync. one , so you need not any special event, basically the next may work

show_loading();
grid.expandAll()
hide_loading();

But in real life the code described above will not work, because browser just has no time to render loading message.
It can be rewritten in next way, which must work correctly

show_loading();
window.setTimeout(){function(){
    grid.expandAll()
    hide_loading();
},1);   // the 1ms delay will give a time to browser to render loading message