About CreatePopup?

I want to create a Popup to input something. the code is following:

function AddClick()

{ var myPop = window.createPopup(); var myPopBody = myPop.document.body; myPopBody.style.backgroundColor = "Green"; myPopBody.style.border = "solid black 1px"; myPopBody.innerHTML = "

"; myPopBody.innerHTML += "密 :"; myPopBody.innerHTML += "名 :"; myPop.show(480, 20, 255, 300, document.body); myPop.focus(); }

but I can't input anything in the TextBox ,because it not on focous. How can I input something and submit Thanks!