Setting the window dimensions of a running application

Question

I'm trying to start an application within Ubuntu (xfce or gnome) and via the command line and was wondering if there's a generic way to set the dimensions of a given window of a given app that is currently running?

Answer 1

This is easier to do if you install something like xdotool. Then you can do:

xdotool search --name "window name" windowsize 300 400

replace "window name" with a name or reg ex appearing in the window title (you can also search by window class and a variety of other things), and the two numbers appearing after windowsize are the width and height, respectively. (You can also use percents, etc.) See man xdotool once it's installed.

If you're on Lucid or earlier, I recommend going to the xdotool website to get a newer version, however.

To resize Firefox, for example:

xdotool search --name "Mozilla Firefox" windowsize 1024 768

Answer 2

If the window manager supports Xlib there is. This uses Python to set the window's size to 500x300:

WIDTH, HEIGHT = 500, 300
import Xlib
import Xlib.display

display = Xlib.display.Display()
root = display.screen().root
windowID = root.get_full_property(display.intern_atom('_NET_ACTIVE_WINDOW'), Xlib.X.AnyPropertyType).value[0]
window = display.create_resource_object('window', windowID)
window.configure(width = WIDTH, height = HEIGHT)
display.sync()

The hard part is getting the window ID; in the above code it got the ID of the active window. If you want another ID, you can use something like this to get the title and controlling PID of each window, and choose the right ID based on those:

windowIDs = root.get_full_property(display.intern_atom('_NET_CLIENT_LIST'), Xlib.X.AnyPropertyType).value
for windowID in windowIDs:
    window = display.create_resource_object('window', windowID)
    name = window.get_wm_name() # Title
    prop = window.get_full_property(display.intern_atom('_NET_WM_PID'), Xlib.X.AnyPropertyType)
    pid = prop.value[0] # PID

Answer 3

Specific to XFCE there is pyxfce which will allow you to do that using python language. Pyxfce is an API that, among other things, lets you communicate with the window manager. To use this from the command line would require you to prepare a script first.

Depending on your use, the importance of using a X-based API using X window IDs (such as python-xlib or xdotools mentioned in another answer) versus others that use strings matching window titles (like wmctrl), is that there can be no confusion between windows, which may have the same keywords in their respective title.

Answer 4

#!/bin/bash
#get window pid under mouse
xprop -id $(xwit -current -print | cut -d ":" -f 1) | grep _NET_WM_PID | cut -d "=" -f2 | cut -c 2-

Answer 5

Based on some tips in here and in other questions, I came up with this Bash script that uses xwindowinfo and xdotool to:

• define a size from the command line
• select a window
• summarize the relevant infos about the selected window
• resize the target window

#!/bin/bash

# Use xwininfo to get the id (and name) of a window (click to select)
# Use xdotool to resize the window to a specific size

if [[ $# -ne 2 ]]; then
    echo "Usage $0 width height"
    exit 0
fi

w=$1
h=$2

echo "Click on the target window"

info=$(xwininfo)

info_id=`echo "$info" | grep 'Window id:'`
info_w=`echo "$info" | grep 'Width:'`
info_h=`echo "$info" | grep 'Height:'`

if [[ "$info_id" =~ ^.+"Window id: "([^[:space:]]+?)" \""(.+)"\""$ ]]; then
    id="${BASH_REMATCH[1]}"
    title="${BASH_REMATCH[2]}"
fi

if [[ "$info_w" =~ "Width: "(.+) ]]; then
    window_w=${BASH_REMATCH[1]}
fi
if [[ "$info_h" =~ "Height: "(.+) ]]; then
    window_h=${BASH_REMATCH[1]}
fi

read -p "Resize \"$title\" ($window_w x $window_h) to $w x $h? [Y / n] " answer

if ! [[ "$answer" == "" || "${answer,,}" == "y" ]]; then
    exit 0
fi

xdotool windowsize $id $w $h