Random order list of list

I have a dynamic PopupMenu defined as follow:

var = { PopupMenu[Dynamic[r3],
{"",{py,px,tn},{px,py,tn},{-px,-py,tn},{px,py,-tn}}
]}


px,px,tnare 3 numbers.

How can I random sort the order of the these elements, keeping the first always ""?

For example, I would like var to contain

{"",{py,px,tn},{px,py,tn},{-px,-py,tn},{px,py,-tn}}


one time, and another time

{"",{px,py,tn},{py,px,tn},{px,py,-tn},{-px,-py,tn}}


Furthermore, I would like the elements of the PopupMenu displayed in the following form: px,py,tn and not {px,py,tn}

• Look up RandomSample[]. – J. M. will be back soon May 29 '17 at 12:07
• @Kuba I want to call it in different part of the notebook and "always" have a different result – Ale1794 May 29 '17 at 12:14
• Like: var := {PopupMenu[ Dynamic[r3], {"", Sequence @@ RandomSample[{{py, px, tn}, {px, py, tn}, {-px, -py, tn}, {px, py, -tn}}]}]}? – Kuba May 29 '17 at 12:16
• – Kuba May 29 '17 at 13:05

var := PopupMenu[Dynamic[x],