How to detect a computer's physical screen size in GTK

Question

I've come across this bug while writing my app. In short, the app's window size is fixed, which does not work well with smaller screens such as in netbooks.

In those, the lower buttons are off the screen limits and cannot be used. I'd like to take this into account in the user interface, but first of all, I'd like to find out what the standard way to detect screen size is in GTK, if there is one.

So does anyone have any ideas on how to do that?

Solution 1

from gi.repository import Gdk
s = Gdk.Screen.get_default()
print(s.get_width())
print(s.get_height())

Of course, if you have multiple screens, this gives the size of a rectangle enclosing them both. This stuff is harder than it sounds, in a world with multiple screens in it...

Solution 2

Here is what I came up with:

from gi.repository import Gdk, Gtk

# Replace w with the GtkWindow of your application
w = Gtk.Window()
# Get the screen from the GtkWindow
s = w.get_screen()
# Using the screen of the Window, the monitor it's on can be identified
m = s.get_monitor_at_window(s.get_active_window())
# Then get the geometry of that monitor
monitor = s.get_monitor_geometry(m)
# This is an example output
print("Heigh: %s, Width: %s" % (monitor.height, monitor.width))

I'm not sure that would be called 'standard,' but I hope that it helps.

Solution 3

I would say what you want is the answer to the following question:

How big would a window be if it was maximized?

Because beside the multiple screen setup there are also other problems like the size of the top panel, bottom panels (no longer in Ubuntu, but maybe other distros), window decorators,... This is actually not handled by Gtk but by the window manager. So I don't see any way to get this number unless you let the windowmanager actually do the maximization.

Therefore the answer to this question is easy:

from gi.repository import Gtk, GObject
w = Gtk.Window()
w.maximize()
def p():
    print w.get_size()
GObject.timeout_add(1000, p)
w.show()
Gtk.main()

So you could create a window, maximize it and then start to populate it with reasonable sized widgets.

Solution 4

You can get width and height in millimeters with this method:

from gi.repository import Gdk
display = Gdk.Display.get_default()
monitor = display.get_monitor(0)
return monitor.get_width_mm(), monitor.get_height_mm()

View more solutions

Comments

[Vilmantas Baranauskas]

Just brainstorming: What about multi-monitor setups with different sizes?

[dobey]

It seems like using the screen size here is the wrong solution. Are there good screenshots of the windows where this is a problem?

[David Planella]

There are a few in the bug reports: bugs.launchpad.net/qreator/+bug/1015138/+attachment/3196020/‌​… and launchpadlibrarian.net/107989779/…

[dobey]

You actually need to poke at the Display rather than the Screen, for getting individual display sizes, IIRC.

[web.learner]

Tested on 14.04, it works.

[guettli]

Thank you very much. Your solution works even if the window is not realized yet.

[guettli]

If you have more than one monitor the screen size is bigger. The above solution does not work if you want the size of a monitor. See the answer of @justin for that.

[NoBugs]

I see DeprecationWarning: get_width is deprecated

[matanster]

Works well for a dual display setup

[matanster]

And for multiple monitors use Gdk.Display().display.get_n_monitors() to get all applicable indices for .get_monitor.