I have a form with 1 textfield and a button. When I click on the button, the system will base on the input of the textfield to search for result. The search result will be displayed in a pop-up window and the parent window does not change. I need to do nullable validation for the textfield. Now my code the function can work, but the search result display in the same parent window.How to make it to be a pop-up window?