Qt: Correct implementation of floating widgets -

i've inherited class qwidget. no code, changes editor.

the way use it:

focuswidget = new focuswidget(this); //this points mainwindow focuswidget->show(); focuswidget->hide(); 

now widget appears (it looks ugly because of bad 4k scaling), @ top left corner of mainwindow. intend use application full screen.

is usage correct?

how can make floating widget?

if want multiple widgets that, how can control position?