Netbeans question

Not sure if this is an appropriate spot, but since my server has no Netbeans
groups, here I am...

If I put together a basic GUI component, a bean panel with nothing in it,
into which I plan on putting other items...  And I put the thing together in
a text editor...  Is it possible to open that file in Netbeans and invoke
the form designer to place items onto the panel via drag-and-drop?  Or am I
pretty much stuck editing text?