winfo

winfo , a builtin Tk command, returns information about a window.

See Also

wm

information related to the Window manager.

Common subcommands

• winfo children window
• winfo class window
• winfo containing ?-displayof window? rootX rootY
• winfo exists window
• winfo fpixels window number
• winfo geometry window
• winfo height window
• winfo ismapped window
  (is window on the screen?)
• winfo manager window
• winfo name window
• winfo parent window
• winfo pixels window number
• winfo pointerx window
• winfo pointerxy window
• winfo pointery window
• winfo reqheight window
• winfo reqwidth window
• winfo rgb window color
• winfo rootx window
• winfo rooty window
• winfo screenheight window
• winfo screenmmheight window
• winfo screenmmwidth window
• winfo screenwidth window
• winfo server window
• winfo toplevel window
• winfo viewable window
• winfo vrootheight window
• winfo vrootwidth window
• winfo vrootx window
• winfo vrooty window
• winfo width window
• winfo x window
• winfo y window

Description

To ensure that the window is fresh, it's usually best to call winfo from a script bound to <Configure>.

Rarely-used subcommands

You probably don't need to use these subcommands, either because they couple to functionality that is largely obsolete in the days of universal full-depth displays or because they require deep knowledge of the X protocol to make use of.

• winfo atom ?-displayof window? name
• winfo atomname ?-displayof window? id
• winfo cells window
• winfo colormapfull window
• winfo depth window
• winfo id window
• winfo interps ?-displayof window?
• winfo pathname ?-displayof window? id
• winfo screen window
• winfo screencells window
• winfo screendepth window
• winfo screenvisual window
• winfo visual window
• winfo visualid window
• winfo visualsavailable window ?includeids?

winfo class

RS 2006-04-12: winfo class returns for toplevels the app name (as from the topmost script), else the Titlecased widget type. Here's a little convenience proc that returns the suitable Tk command for deserializing a widget:

proc winfo'class w {
    if {[winfo toplevel $w] eq $w} {return toplevel}
    string tolower [winfo class $w]
}

MG: This seems to only be the case for ".". Other toplevels seem to return "Toplevel" as you'd expect. (Anyone know why it returns the app name for ".", though? Curious what the thought behind it was.)

DKF: It relates to option database support. In particular, other names would be used by completely different applications (e.g. Firefox, Xterm, etc.)

MG Ahh, I see. Thanks :)

The Window Under the Pointer

PYK 2017-05-16: auriocus provided this in the Tcl Chatroom:

# print the window name under the mouse cursor
proc pickwin {} {
    after 1000 {
        set pickwidget [winfo containing {*}[winfo pointerxy .]]
        if { $pickwidget ne {} } {
            puts $pickwidget
            foreach option [$pickwidget configure] {
                # leave out synonym options
                if { [llength $option] != 5 } continue
                lassign $option name dbname dbclass defvalue currentvalue
                if { $defvalue != $currentvalue } { puts "  $name $currentvalue" }
            }
        } else { puts "No widget under cursor." }
    }
}