Tk TopLevel window

Ruby
1

I have been searching for awhile but cannot find the answer to my
question.
I have a TkRoot window that when a button is clicked, a new TkToplevel
window is created.

I don’t want the user to be able to get focus of the TkRoot window until
the TkToplevel window is closed. Much like a dialog box. I could
probably catch the FocusOut event on the TkToplevel window and grab
focus again but that seems like a hacked way to do it. Is there an
easier way?

2

From: Jason [email protected]
Subject: Tk TopLevel window
Date: Sat, 30 Jun 2007 23:58:33 +0900
Message-ID: [email protected]

I have a TkRoot window that when a button is clicked, a new TkToplevel
window is created.

I don’t want the user to be able to get focus of the TkRoot window until
the TkToplevel window is closed. Much like a dialog box. I could
probably catch the FocusOut event on the TkToplevel window and grab
focus again but that seems like a hacked way to do it. Is there an
easier way?

Please use TkWindow#set_grab/release_grab methods,
and some kinds of tkwait methods.

See also Tcl/Tk’s manuals about ‘tkwait’ and ‘vwait’.

For example,

require ‘tk’

def create_onetime_toplevel(btn)
top = TkToplevel.new(btn).withdraw
TkLabel.new(top, :text=>'self.object_id == ’ <<
top.object_id.to_s).pack
e = TkEntry.new(top).pack
TkButton.new(top, :text=>‘CLOSE’, :command=>proc{top.destroy}).pack
top.deiconify
e.focus
top.set_grab
top.wait_destroy # same as top.tkwait_destroy
top.release_grab
end

def create_reusable_toplevel(btn, var)
top = TkToplevel.new(btn).withdraw
TkLabel.new(top, :text=>'self.object_id == ’ <<
top.object_id.to_s).pack
e = TkEntry.new(top).pack
TkButton.new(top, :text=>‘CLOSE’,
:command=>proc{top.withdraw; var.value = 1}).pack
[top, e]
end

root = Tk.root
TkEntry.new.pack.focus
TkButton.new(:text=>‘QUIT’, :command=>proc{exit}).pack(:side=>:bottom)

b1 = TkButton.new(:text=>‘onetime toplevel’,
:command=>proc{create_onetime_toplevel(b1)}).pack

b2 = TkButton.new(:text=>‘reusable toplevel’).pack
wait_var = TkVariable.new

reusable_top, entry = create_reusable_toplevel(b2, wait_var)

b2.command{
reusable_top.deiconify
entry.focus
reusable_top.set_grab
wait_var.tkwait # wait for writing to wait_var.
# It’s similar to wait_var.wait,
# but tkwait checks the existence of Tk’s root
window.
# When the root window is destroyed, tkwait will
finish.
reusable_top.release_grab
reusable_top.withdraw
}

Tk.mainloop