[ttk::panedwindow ] creates and manipulates ttk paned window widgets.

See Also

paned window


official reference

See Changing Widget Colors for style options


Resize when client window size changes

SPB 2015-09-14: I wish to have the "-stretch last" or "-stretch never" behaviour of tk::panedwindow, but I cannot figure out how one might do that with ttk::panedwindow. Any suggestions? (My specific problem is that I have a frame F packed into the bottom pane of my panedwindow, that I wish to always take up solely the space of the frame, unless the user moves the sash. Setting the weight to 0 fails, as the pane acquires no space at all and the frame F remains invisible when added to the PW. Setting non-zero weights causes extra (empty) space to become proportionally allocated to F, when I don't want it to get any extra space at all.) Is there a way to have a pane of a ttk::panedwindow to allocate the space of the frame it contains, but no more than that? Thank you!

HaO Joe English answered on the core list [L1 ]:

ttk::panedwindow only honors geometry requests from slaves if they are currently unmapped. IIRC, the core panedwindow works the same way.

I do not recall the exact details, but doing otherwise led to erratic behavior when the user dragged the sash, especially in combination with ill-behaved megawidgets.

If you unmap and remap the pane after adding subwindows, that will retrigger geometry propagation.

Ordered list of managed slaves

WHD 2010-04-14: Is there a way to get a list of the names of the managed subwindows in index order? I can refer to managed subwindows from 0 to end, but I don't see any way in the interface to determine how many managed windows there are, nor the order in which they are stacked. winfo children returns the children of the panedwindow in the order of creation, which can be very different.

MG: The ttk::panedwindow has some undocumented subcommands, the one you want is $panedWindow panes:

(bin) 1 % pack [ttk::panedwindow .pw]
(bin) 2 % .pw foobar
bad command "foobar": must be add, configure, cget, forget, identify, insert, instate, pane, panes, sashpos, or state
(bin) 3 % set tcl_patchLevel

$panedWindow panes                            ;# returns a list of all widgets being used as panes, in order
$panedWindow add $widget [-option value ...]  ;# seems to be an alias for $panedWindow insert end $widget [-option value ...]

MHo 2008-04-09: Does someone know if and how it's possible to determine the dimension of a pane inside a panedwindow? I have a canvas inside a pane that holds an image. If resizing / maximizing the top-level windows, everything should grow to use the extra space. But the pane itself says it is has the dimension 1x1, and the canvas stays as its initial size (if I don't specify such initial size, something else goes wrong that is beyond the scope of this question...).

MG: I've noticed with this (and other Tile widgets) in Windows / Tk 8.5 that there's a delay before sizes and things fully update - calling update and/or update idletasks doesn't resolve the problem. I've had to resort to doing something like

$widget add $foo
after 25 [list doStuffWith $widget]

to give the widgets time to update their sizes and report the correct ones back. See if that resolves the problem? In your case, winfo width and winfo height on the canvas may work, too?

Create a Custom Sash Handle bar

In the default theme the sash handle bar is empty. So it is not obvious that it is a panedwindow. This little piece of code creates a new style for the panedwindow which as a Firefox-like sash handle bar.

image create photo img:sash -data {

ttk::style element create Sash.xsash image \
        [list img:sash ] \
        -border {1 1} -sticky ew -padding {1 1}

ttk::style layout TPanedwindow {

Also see Custom sash handle for panedwindow


package require Ttk

# ttk::setTheme clam

set xf [ttk::frame .f]
set pw [ttk::panedwindow -orient horizontal ]

ttk::frame $pw.f1
ttk::label $pw.f1.l -text "Frame 1"
pack $pw.f1.l

ttk::frame $pw.f2
ttk::label $pw.f2.l -text "Frame 2"
pack $pw.f2.l

$pw add $pw.f1
$pw add $pw.f2

pack $pw -expand 1 -fill both
pack $xf -expand 1 -fill both


HaO 2016-05-19: I asked on clt "ttk::panedwindow minheight and sash" about a minimum size of a managed window. For me, it is often not clear to the user that:

  • there is a pane people may drag
  • there are two windows when the sash is at one of the borders.

Unfortunately, the sash may move to the border by a window resize or at application statup. The user may not be the cause for the hidden panes.

I tried the upper "sash icon". It did not work for me, as the sash icon itself was often hidden on resizing.

Within the clt thread, Brad Lanam supplied the following script which resets the sas to position 30 if dragged to 0:

proc dosash { w args } {
  set sp [.p sashpos 0]
  if { $sp < 20 } {
    .p sashpos 0 30

proc conf { w args } {

proc out { f } {
  .p forget $f
  if { [llength [.p panes]] == 0 } {
    wm withdraw .
  wm manage $f
  bind $f <ButtonRelease-1> [list in $f]
  $f configure -background pink

proc in { f } {
  wm forget $f
  .p add $f
  wm deiconify .
  bind $f <ButtonRelease-1> [list out $f]
  $f configure -background [string trim $f .]

ttk::style configure TPanedwindow \
    -background blue
ttk::style configure Sash -sashthickness 20

ttk::panedwindow .p -orient horizontal -style TPanedwindow
pack .p -expand true -fill both
pack propagate .p false
frame .cyan -background cyan -height 200 -width 200
ttk::label .cyan.txt -text {This is frame one.}
pack .cyan.txt
frame .yellow -background yellow -height 200 -width 200
ttk::label .yellow.txt -text {This is frame two.}
pack .yellow.txt
.cyan configure -height 200 -width 200
.yellow configure -height 200 -width 200
.p add .cyan -weight 1
.p add .yellow -weight 1

bind .cyan <ButtonRelease-1> [list out .cyan]
bind .yellow <ButtonRelease-1> [list out .yellow]
bind .cyan <ButtonRelease-2> [list .cyan configure -width 420]
bind .yellow <ButtonRelease-2> [list .yellow configure -width 420]
bind .p <Configure> [list conf %W]
bind .p <ButtonRelease-1> [list dosash %W]
bind .cyan <Configure> [list conf %W]
bind .yellow <Configure> [list conf %W]

Lock pane

PO 2017-05-12: Had the need to lock panes. Here is a solution using bindtags:

package require Tk

proc LockPane { w onOff } {
    if { $onOff } {
        bindtags $w { $w . all }
    } else {
        bindtags $w { $w TPanedwindow . all }

set fr .fr
frame $fr
pack $fr -expand 1 -fill both

set vpane $fr.vpane
ttk::panedwindow $vpane -orient vertical
pack $vpane -side top -expand 1 -fill both

set tf $vpane.tfr
set bf $vpane.bfr
frame $tf -bg red
frame $bf -bg green
pack $tf -expand 1 -fill both
pack $bf -expand 1 -fill both

$vpane add $tf
$vpane add $bf

set hpane $bf.hpane
ttk::panedwindow $hpane -orient horizontal
pack $hpane -side top -expand 1 -fill both

set lf $hpane.lfr
set rf $hpane.rfr
frame $lf -bg yellow
frame $rf -bg magenta
pack $lf -expand 1 -fill both
pack $rf -expand 1 -fill both

$hpane add $lf
$hpane add $rf
button $tf.b1 -text "Lock vertical"   -command "LockPane $vpane true"
button $tf.b2 -text "Lock horizontal" -command "LockPane $hpane true"
pack $tf.b1 $tf.b2 -fill x
button $lf.b1 -text "Unlock vertical"   -command "LockPane $vpane false"
button $lf.b2 -text "Unlock horizontal" -command "LockPane $hpane false"
pack $lf.b1 $lf.b2 -fill x

wm minsize . 300 200
$hpane sashpos 0 150
$vpane sashpos 0 100