Who is familiar with ExtJS, questions about closing the panel?

Who is familiar with ExtJS, questions about closing the panel?
For example: I wrote a var win = new Ext.window ({b.js}) in A.js; Win.show ();

Opens a new window and then writes a button to submit the message in B.js.

Now I want to be able to close win.show () after B's submission, what should I do when I come out of the window?

I try to use Window.close () in B, can't close, or can I call a fork event in the window to close?

With the Close event, I remember a question, close seems to be forever destroyed this object, you seem to re-write the method, re-put this window new out, with hide just hidden, in the development process with hide there are some problems, suggest close.
function Newwin () {

Arti_win = new Ext.window ({
Layout: ' Fit ',
width:860,
height:570,
Closeaction: ' Close ',//mostly set here, with hide and close
Resizable:false,
Shadow:true,
Closable:true,
Bodystyle: ' padding:5 5 5 5 ',
Animcollapse:true,
Modal:true,
Autodestroy:true,
Items:[form]
});
}

Solved, now to share
Parent. EXT.GETCMP (' B-win '). Close ();
You can use this.

Who is familiar with ExtJS, questions about closing the panel?