aras. uiReShowItem how to use ?

In one of my requirement after hide / show relationship grid column based parent field value, I want to refresh Item form/grid to see changes done. For this purpose I am using 

aras.uiReShowItem in onformPopulate event it keeps on loading item. And item doesn't get load. 

Can someone explain how can I fix this? 

Also of you have api on how to hide. Show relationship column s please share it.